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HomeMy WebLinkAboutB10-0105 Geotechnical Report , , �KOECHLEIN CONSULTING ENGINEERS, INC. � GEOTECHNICAL AND MATERIALS ENGINEERS �r I GEOTECHNICAL REPORT PROPOSED WEST VAIL FIRE STATION 2399 NORTH FRONTAGE ROAD WEST VAIL, COLORADO �:;��`_ ,�.,�'�!!��!��'� ` i ^r De�artment �T9�t� o.. 'i t.�*°i � �.. ;u:"'� --� f .. i�i i �....�.1 '� '�:'�nS `.J t'• S... -.. �....�....,_.�....�,� - . C .. ' .. ... ,�. `� ..- .c! �'�-�.- -9 a" , ; . .,.,c, i: ,'� rc , ,`4 � ` _ fi � � � � V � ��% � - -.. . � ..�.. . " .,.. �'1 r � . - . _. .. � D � �� � . . -.�. .� P ._ -c " �rc " , '. , ���. -. _��, . � "r � j% . _ . _._� �_ , :;d MAY 1 2 2010 � •� + �.l Ot � i .. � • C _.. _., t. .. �.. � CC ;.i C . `- , .. .: . , � 1 J C ,�. " ' '' „ i�'l0 bc. . ., _v ^ .: . . � � � TOWN OF VAIL _ _ � _, r :� ,,� 1 $t l. . : - . . . c !G ''�f G�G ;:�3 Of thlS�r'.. - . .. � , . PLAi�S�CAMIiVER: [?ATt: G° �o � ° Prepared for: Todd Oppenheimer Department of Public Works Town of Vail 1309 Elkhorn Drive Vail, CO 81657 Job No. 09-033 August 6, 2009 DENVER: ]2364 West Alameda Prkwy.,Suite 115,Lakewood,CO 80228(303)989-1223 GRAND JUNCTION:529 25 1/2 Rd�Suite 201 •Grand Junction,CO SISOS(970)241-7700 AVON/SILVERTHORNE: (970)949-6009 f � August 6,2009 KOECHLEIN CONSULTING ENGINEERS,INC. JobNo.09-033 Geotechnical and Materials Engineers TABLE OF CONTENTS SCOPE 1 EXECUTIVE SUMMARY 1 SITE CONDITIONS 4 PROPOSED CONSTRUCTION 5 SUBSURFACE EXPLORATION 5 SUBSURFACE CONDITIONS 6 RADON 7 MOLD 8 EXISTING STRUCTURES 8 EXISTING FILL 9 GROUND WATER 10 EXCAVATIONS ,,,� 11 SHORING 12 SEISMICITY 12 FOUNDATIONS 12 FLOOR SYSTEM 14 EXTERIOR SLABS-ON-GRADE 16 FOUNDATION DRAINAGE 17 LATERAL WALL LOADS 18 RETAINING WALLS 19 SURFACE DRAINAGE 20 IRRIGATION 21 COMPACTED FILL 21 PAVEMENT DESIGN 22 Flexible Pavement Desi�n 23 Rigid Pavement Design 24 Pavement Materials 25 Subgrade Stabilization 26 Construction Considerations 27 Draina�e 28 LIMITATIONS 28 , , August 6,2009 KOECHLEIN CONSULTING ENGINEERS,INC. JobNo.09-033 Geotechnica! and Materials Engineers LIST OF FIGURES VICINITY MAP Fig. 1 LOCATIONS OF EXPLORATORY BORINGS Fig. 2 LOGS OF EXPLORATORY BORINGS Fig. 3 LEGEND OF EXPLORATORY BORINGS Fig. 4 GRADATION TEST RESULTS Figs. 5 and 6 SWELL-CONSOLIDATION TEST RESULTS Fig. 7 FOUNDATION EXCAVATION RECOMMENDATIONS Fig. 8 TYPICAL EXTERIOR WALL DRAIN DETAIL Fig. 9 TYPICAL RETAINING WALL DRAIN DETAIL Fig. 10 SUMMARY OF LABORATORY TEST RESULTS Table I PAVEMENT DESIGN CALCULATIONS Appendix A PAVEMENT CONSTRUCTION RECOMMENDATIONS Appendix B . July 31,2009 KOECHLEIN CONSDLTING ENGINEERS,INC. JobNo.09-033 Geotechnica! and Materials Engineers SCOPE This report presents the results of a geotechnical subsurface exploration for the � proposed fire station to be constructed at 2399 North Frontage Road West in Vail, Colorado. The approximate site location is shown on the Vicinity Map, Fig. 1. The purpose of this report is to present our evaluation of the subsurface conditions at the site and to provide geotechnical recommendations for the proposed fire station. This report includes descriptions of subsurface soil and ground water conditions encountered in the exploratory borings, recommended foundation design and construction criteria, allowable bearing capacity, recommended pavement sections, and recommended pavement design and construction criteria for the proposed construction. This report was prepared from data developed during our subsurface exploration and our experience with similar projects and subsurface conditions in the area. The recommendations presented in this report are based on a fire station being constructed in the location shown on the Locations of Exploratory Borings, Fig. 2. We should be contacted by the contractor and/or owner to review our recommendations when final plans for the structure have been completed. A summary of our findings and conclusions is presented in the following paragraphs. . EXECUTIVE SUMMARY 1. Subsurface conditions encountered in the exploratory borings varied. The subsurface conditions encountered in boring TH-1 consisted of 1.5 inches , , August 6,2009 KOECHLEIN CONSULTING ENGINEERS,INC. JobNo.09-033 Geotechnical and Materials Engineers of asphalt underlain by 4 inches of roadbase. Beneath the roadbase, subsurface conditions consisted of a medium dense, gravelly, sandy, clayey silt with scattered cobbles to the maximum depth explored of 12.0 feet. The subsurface conditions encountered in boring TH-2 consisted of 6 inches of roadbase underlain by existing fill to a depth of 11.0 feet. The existing fill is characterized by a stiff to very stiff, gravelly, sandy clay with scattered cobbles and organics. Underlying the existing fill, subsurface conditions consisted of a stiff, sandy, silty clay to a depth of 13.0 feet. Beneath the sandy, silty clay, subsurface conditions consisted of medium dense to dense gravel with scattered cobbles and boulders and lenses of fine sands to the maximum depth explored of 20.0 feet. The subsurface conditions encountered in boring TH-3 consisted of 3.5 inches of asphalt underlain by 4 inches of roadbase. Beneath the roadbase, subsurface conditions consisted of a stiff, sandy, silty clay to a depth of 14.0 feet. Below the sandy, silty clay, subsurface conditions consisted of medium dense to dense gravel with scattered cobbles and boulders and lenses of fine sands to the maximum depth explored of 20.0 feet. Refer to the SUBSURFACE CONDITIONS section of this report for additional information. 2. At the time of drilling, ground water was encountered in exploratory boring TH-2 at a depth of 11.5 feet and in exploratory boring TH-3 at a depth of 14.0 feet. No free groundwater was encountered in exploratory boring TH-1 to the maximum depth explored of 12.0 feet. Refer to the GROUND WATER section of this report for additional details. 3. Currently, a four-tiered, gravity retaining wall borders the north and west sides of the site. Special considerations should be taken into account during construction due to the presence of existing structures. Refer to the EXISTING STRUCTURES section of this report for additional information. 4. Existing fill was encountered in exploratory boring TH-2 to a depth of 11.0 feet. The existing fill is characterized by a black, tan, olive, moist, stiff to very stiff, gravelly, sandy clay with scattered cobbles and organics. Refer to the EXISTING FILL section of this report for additional information. 5. We anticipate that the subsurface conditions at the foundation elevation for the proposed fire station will consist of either sandy, silty clay, existing 2 x , � August 6,2009 KOECHLEIN CONSULTING ENGINEERS,INC. ' JobNo.09-033 Geotechnical and Materials Engineers � fill, or gravelly, sandy, clayey silt with scattered cobbles. Due to the '"� presence of existing fill at the foundation elevation, special considerations should be taken into account when constructing the foundation system for the proposed fire station. Refer to the FOLTNDATIONS section of this report for more details. 6. We anticipate that the subsurface conditions at the proposed slabs-on- grade elevation will consist of either sandy, silty clay, existing fill, or gravelly, sandy, clayey silt with scattered cobbles. Due to the presence of existing fill, special considerations should be taken into account when constructing slabs-on-grade. Refer to the FLOOR SYSTEM and EXTERIOR SLABS-ON-GRADE sections of this report for more details. 7. Based on the conditions encountered in the exploratory borings we anticipate that heavy duty construction equipment will be necessary to complete the required excavations. Refer to the EXCAVATIONS section of this report for more details. 8. Based on the subsurface soil profile, this site has a seismic site classification of Site Class C. Refer to the SEISMICITY section of this report for additional details. 9. Drainage around the fire station should be designed and constructed to provide for rapid removal of surface runoff and avoid concentration of water adjacent to foundation walls. Refer to the SURFACE DRAINAGE section of this report for details. S- 10. The potential for radon gas is a concern in the area. Building design should include ventilation systems for below grade levels. Refer to the RADON section of this report for additional details. 11. Mold has become a concern with new construction. Refer to the MOLD section of this report for additional details. A � 12. Laboratory testing on the subgrade samples obtained from exploratory boring TH-1 indicated that the soils classify as A-4 soils in accordance with the AASHTO classification system. The pavement designs presented in this report are based on the subgrade soils classifying as A-4 soils. k � 3 August 6,2009 KOECHLEIN CONSULTING ENGINEERS,INC. JobNo.09-033 Geotechnical and Materials Engineers 13. Pavement thickness recommendations for the proposed parking lot and access drive are presented in the PAVEMENT DESIGN section and in Appendix A of this report. 14. Pavement construction recommendations are presented in the PAVEMENT DESIGN and Construction Considerations sections of this report as well as in Appendix B. SITE CONDITIONS The proposed fire station will be located at 2399 North Frontage Road West in Vail, Colorado. The lot is accessed from North Frontage Road West, which borders the site to the south. The site is bordered to the west by an existing retaining wall system and to the north by vacant land. The eastern edge of the site is bordered by a gas station. Based on conversations with the Town of Vail, it is our understanding that the site was previously occupied by a commercial restaurant. The structure was demolished prior to our subsurface exploration. At the time of our subsurface exploration,the subject lot was vacant and being used as a parking lot. The existing parking lot has been paved with flexible pavement. Site topography is generally level with a gentle slope down towards a southeasterly direction at an approximate grade of 5 to 10 percent. The topography on the western side of the lot is steeply sloping to the southeast at an approximate grade of 35 to 40 percent. Vegetation consists of two landscaped islands containing grasses and small pine trees. Pine and aspen trees, grasses, and weeds surround the site. Large boulders have been incorporated into the surrounding landscaping. 4 . � � August 6,2009 KOECHLEIN CONSULTING ENGINEERS,INC. JobNo.09-033 Geotechnica! and Materials Engineers PROPOSED CONSTRUCTION Prior to the start of our subsurface exploration, a site plan of the proposed fire station was provided by the Town of Vail. Based on our conversations with the Town of t Vail, we understand that the grading of the site will be cut down 2 feet for the proposed fire station as well as the proposed parking lot. We anticipate that the proposed fire station will consist of a two to three-story building with a portion of the building below s grade on the western side. We anticipate that the fire station will be constructed of cast- in-place concrete and wood frame construction with slabs-on-grade. We anticipate that a portion of the existing retaining wall system will be removed and two new retaining walls will be constructed. Due to the presence of existing fill and the construction of a portion of the building below grade level, we anticipate that excavations for the proposed fire station will vary from 4 to 14 feet in depth, after reducing the site grade by 2 feet. In addition, we anticipate that an access drive and parking lot will be constructed adjacent to the proposed fire station. We anticipate that the proposed access drive and parking lot will be of both flexible and rigid pavement construction. SUBSURFACE EXPLORATION Subsurface conditions were explored at this site on July 23, 2009 by drilling three ' exploratory borings (TH-1 thru TH-3) with a 4-inch, solid-stem auger mounted on a � tracked drill rig at the locations shown on the�Locations of Exploratory Borings, Fig. 2. � � { 5 August 6,2009 KOECHLEIN CONSULTING ENGINEERS,INC. JobNo.09-033 Geotechnica! and Materials Engineers An engineer from our office was on site during the subsurface exploration to supervise the drilling of the exploratory borings and to visually classify and document the subsurface soils and ground water conditions. Graphical logs of the subsurface conditions encountered in the exploratory borings are presented on the Logs of Exploratory Borings,Fig. 3; and on the Legend of Exploratory Borings,Fig. 4. Selected samples were tested in our laboratory to determine their natural moisture content, natural dry density, gradation properties, Atterberg limits, and swell- consolidation potential. Results of the laboratory testing are presented on the Logs of Exploratory Borings, Fig. 3; on the Gradation Test Results, Figs. 5 and 6; on the Swell- Consolidation Test Results, Fig. 7; and on the Summary of Laboratory Test Results, Table I. SUBSURFACE CONDITIONS Subsurface conditions encountered in the exploratory borings varied. The subsurface conditions encountered in boring TH-1 consisted of 1.5 inches of asphalt underlain by 4 inches of roadbase. Beneath the roadbase, the subsurface conditions consisted of a tan to brown, slightly moist, medium dense, gravelly, sandy, clayey silt with scattered cobbles to the maximum depth explored of 12.0 feet. The subsurface conditions encountered in boring TH-2 consisted of 6 inches of roadbase underlain by existing fill. The existing fill is characterized by a black, tan, olive, moist, stiff to very 6 August 6,2009 KOECHLEIN CONSULTING ENGINEERS,INC. JobNo.09-033 Geotechnical and Materials Engineers stiff, gravelly, sandy clay with scattered cobbles and organics to a depth of 11.0 feet. Beneath the existing fill, the subsurface conditions consisted of a brown, red brown, slightly moist to wet, stiff, sandy, silty clay to a depth of 13.0 feet. Below the sandy, silty clay, the subsurface conditions consisted of red brown, wet, medium dense to dense gravel with scattered cobbles and boulders and lenses of fine sands to the maximum depth explored of 20.0 feet. Subsurface conditions encountered in boring TH-3 consisted of 3.5 inches of asphalt underlain by 4 inches of roadbase. Underlying the roadbase, the subsurface conditions consisted of a brown, red brown, slightly moist to moist, stiff, sandy, silty clay to a depth of 14.0 feet. Below the sandy, silty clay, the subsurface conditions consisted of red brown, wet, medium dense to dense gravel with scattered cobbles and boulders and lenses of fine sands to the maximum depth explored of 20.0 feet. At the time of drilling, ground water was encountered in boring TH-2 at a depth of 11.5 feet and in boring TH-3 at a depth of 14.0 feet. Ground water was not encountered in boring TH-1 to the maximum depth explored of 12.0 feet. RADON In recent years, radon gas has become a concern. Radon gas is a colorless, odorless gas that is produced by the decay of minerals in soil and rock. The potential for radon gas in the subsurface strata of mountain terrain is likely. Because we anticipate that 7 August 6,2009 KOECHLEIN CONSULTING ENGINEERS,INC. JobNo.09-033 Geotechnical and Mate�ials Engineers the building will be constructed with a portion of the building below grade, the risk of radon gas occurring in the building will be moderate. The portion of building below grade should be designed with a ventilation system in order to reduce the risk of radon gas occurring in the building. MOLD Mold has become a concern with new construction. Mold tends to develop in dark or damp areas such as below grade levels, under floor spaces, or bathrooms. Recommendations for the prevention, remediation, andlor mitigation of mold is outside the scope of this report. We recommend that the owner contact a Professional Industrial Hygienist for recommendations for the prevention, remediation, and/or mitigation of mold. EXISTING STRUCTURES � At the time of our subsurface exploration, an existing, four-tiered retaining wall was located on the western side of the site. Based on our observations, the wall is constructed out of stacked timbers supported by additional timbers arranged perpendicularly to the face of the wall, embedding into the slope and appears to be a timber crib wall. Mesh wire has been installed on the back side of the timbers and then backfilled with large gravels. We will be conducting a separate exploration to assess the 8 f" t August 6,2009 KOECHLEIN CONSULTINC ENGINEERS,INC. JobNo.09-033 Geotechnica! and Materials Engineers stability of the retaining wall and surrounding slope prior to any excavation. Although we anticipate that the existing foundations were removed during the demolition of the previous development, it is possible that existing foundations or fill from the demolition could be encountered during construction of the proposed fire station. We recommend that shallow foundations or existing fill encountered during excavation be completely removed and replaced with compacted structural fill prior to construction of the proposed fire station. Compacted structural fill, required after the r removal of the existing foundation systems or existing fill, should be moisture treated and compacted as recommended in the COMPACTED FILL section of this report. EXISTING FILL Existing fill was encountered at this site in exploratory boring TH-2 to a depth of 11.0 feet. Greater depths of existing fill could be encountered across the site. The existing fill is characterized by a black, tan, olive, moist, stiff to very stiff, gravelly, sandy clay with scattered cobbles and organics. Based on review of topographic maps of varying ages of this area, we anticipate that this site was once occupied by a creek drainage. Due to the presence of organics, the depth of fill, and the unknown placement method, we do not recommend that the proposed structures be constructed on the existing fill. The extents of the existing fill cannot be accurately identified due to the limited number of borings drilled at this site. If the owner would like to determine the extents of 9 August 6,2009 KOECHLEIN CONSULTING ENGINEERS,INC. JobNo.09-033 Geotechnical and Materials Engineers the existing fill, we recommend an additional exploration using exploratory test pits be performed. Existing fill should be removed and replaced with properly moisture treated and compacted new structural fill below the area of proposed construction. Refer to the COMPACTED FILL section of this report for additional information. Based on the drilling characteristics and quality of the existing fill encountered in boring TH-2, we anticipate that, if deleterious materials are removed, the existing fill is suitable for use as structural fill. However, a representative of our office must observe the excavated fill to confirm its suitability for use on this project, prior to placement. GROUND WATER At the time of drilling, ground water was encountered in boring TH-2 at a depth of 11.5 feet and in boring TH-3 at a depth of 14.0 feet. Ground water was not encountered in boring TH-1 to the maximum depth explored of 12.0 feet. Based on the conditions encountered during drilling, we anticipate that ground water will not influence the construction of the majority of the proposed fire station. However, it is possible that ground water may be encountered when constructing the portion of building below grade along the western edge of the proposed fire station. In addition, ground water may be encountered at shallower depths during wetter times of the year. Ground water may be 10 Y August 6,2009 KOECHLEIN CONSULTING ENGINEERS,INC. JobNo.09-033 Geotechnical and Materia[s Engineers controlled by excavating shallow trenches within the foundation excavation and sloping them to daylight or a sump pit where water can be pumped out. EXCAVATIONS Due to the presence of existing fill, we anticipate that excavations of up to 14 feet will be required for construction of the proposed fire station. Based on the subsurface conditions encountered in the exploratory borings, it is our opinion that heavy duty construction equipment will be necessary to complete the required excavations. Existing fill was encountered to a depth of 11.0 feet; however, greater depths of existing fill could be encountered across the site. In addition, asphalt was encountered to varying depths of 1.5 to 3.5 inches; however, greater amounts of asphalt could be encountered across the site. All existing fill and asphalt should be removed from below ; the proposed fire station prior to construction. Care needs to be exercised during construction so that the excavation slopes remain stable. In our opinion, the existing fill, the sandy silty clay, and the gravelly, sandy, clayey silt with scattered cobbles classify as Type B soils in accordance with OSHA regulations. OSHA regulations should be followed in all excavations and cuts. 11 August 6,2009 KOECHLEIN CONSULTINC ENGINEERS,INC. JobNo.09-033 Geotechnical and Materials Engineers SHORING We anticipate that excavation depths up to 14 feet on the western side of the proposed fire station may be necessary to complete the proposed construction. Due to the depth of excavation it may not be possible to slope all of the excavation sides as required by OSHA regulations. We anticipate that this deep excavation will need to be shored during construction activities. We recommend a contractor specializing in shoring design and construction be contacted for design recommendations and construction of the shoring. SEISMICITY The subsurface soil conditions encountered within the exploratory borings indicate that the soil profile classifies as very dense soil and soft rock in accordance with the 2006 International Building Code (IBC). Based on this classification, it is our opinion that the subject site has a seismic site classification of Site Class C. FOUNDATIONS We anticipate that the subsurface conditions at the foundation elevation for the proposed fire station will consist of either sandy, silty clay, existing fill, or gravelly, sandy, clayey silt with scattered cobbles. Laboratory analysis indicates that the sandy, silty clay has nil swell potential and therefore is non-expansive. We do not recommend 12 August 6,2009 KOECHLEIN CONSDLTING ENGINEERS,INC. JobNo.09-033 Geolechnical and Materials Engineers that a spread footing foundation system be constructed on the existing fill, however, if all existing fill is removed and replaced with properly moisture treated, compacted structural fill, it is our opinion that a spread footing foundation system may be used to support the proposed fire station. A spread footing foundation system constructed on either the gravelly, sandy, clayey silt with scattered cobbles, the sandy, silTy clay, or new structural fill could support the proposed fire station with a low risk of movement. We recommend that spread footings be designed and constructed to meet the following criteria: 1. Footings should be supported by either the sandy, silty clay, the gravelly, sandy, clayey silt with scattered cobbles, or properly moisture conditioned and compacted new fill. All existing fill should be removed and replaced with a properly moisture conditioned and compacted non-expansive structural fill. 2. We recommend footings constructed on the either the sandy, silty clay, the gravelly, sandy, clayey silt with scattered cobbles, or properly moisture conditioned and compacted new fill be designed for a maximum allowable soil bearing pressure of 2,500 psf. 3. Spread footings constructed on the sandy, silty clay, the gravelly, sandy, clayey silt with scattered cobbles, and properly moisture conditioned and compacted new fill may experience up to 1 inch of differential movement between foundation elements. Because the soils are clayey, we anticipate that the majority of the differential movement will occur after construction. 4. Compacted fill placed beneath spread footings should extend at a 1 to 1 (Horizontal to Vertical) slope from the outside edge of the footings. Excavation recommendations beneath spread footings are shown in the Foundation Excavation Recommendations,Fig. 8. 5. Foundation systems should be designed to span a distance of at least 10.0 feet in order to account for anomalies in the soil or fill. 13 f August 6,2009 KOECHLEIN CONSULTING ENGINEERS,INC. JobNo.09-033 Geotechnical and Materials Engineers 6. The base of the exterior footings should be established at a minimum depth below the exterior ground surface, as required by the local building code. The Town of Vail requires a depth for frost protection of 4 feet. 7. Column footings should have a minimum dimension of 24 inches square and continuous wall footings should have a minimum width of 16 inches. Footing widths may be greater to accommodate structural design loads. 8. Fill should be placed and compacted as outlined in the COMPACTED FILL section of this report. We recommend that a representative of our office observe and test the placement and compaction of structural fill used in foundation construction. It has been our experience that without engineering quality control, poor construction techniques occur which result in unsatisfactory foundation performance. 9. We recommend that a representative of our office must observe the completed foundation excavation. Variations from the conditions described in this report, which were not indicated by our borings, can occur. The representative can observe the excavation to evaluate the exposed subsurface conditions and make the necessary recommendations. FLOOR SYSTEM We anticipate that the subsurface conditions at the floor slab elevations for the proposed fire station will consist of the sandy, silty clay, existing fill, or the gravelly, sandy, clayey silt with scattered cobbles. It is our opinion that the floor slabs bearing on the sandy, silty clay, or the gravelly, sandy, clayey silt with scattered cobbles should have a low risk of movement. Floor slabs constructed on a combination of existing fill and natural soils will have a high risk of differential movement. If the owner is willing to accept a high risk of movement, then slabs-on-grade may be constructed on the existing fill and natural soils. If the owner would like to reduce the risk of movement to a low 14 August 6,2009 KOECHLEIN CONSULTING ENGINEERS,INC. JobNo.09-033 Geotechnica[ and Materials Engineers level, we recommend removing all of the existing fill and replacing it with properly moisture conditioned and compacted new structural fill. We recommend the following precautions for the construction of slab-on-grade floors: 1. If the owner is willing to accept a high risk of movement, slab-on-grade floors may be constructed on the existing fill. 2. If the owner would like to reduce the risk of slab movement, slab-on-grade floors could be constructed on properly moisture treated natural soils or a combination of properly moisture treated natural soils and new structural fill. 3. Slabs may be placed on the properly scarified and moisture treated natural soils or structural fill. 4. Slabs-on-grade may be designed using a modulus of subgrade reaction of 90 psi. 5. Slabs should be separated from exterior walls and interior bearing members. Vertical movement of the slabs should not be restricted. � 6. Slab-bearing partitions should be minimized. Where such partitions are necessary, a slip joint should be constructed to allow free vertical movement of the partitions 7. Heating and air conditioning systems supported by slabs should be provided with flexible connections so that slab movement is not transmitted to duct work. � 8. Freyuent control joints should be provided in all slabs to reduce problems associated with shrinkage. 9. Fill beneath slabs-on-grades may consist of approved on-site soils or approved fill. Fill should be placed and compacted as recommended in the COMPACTED FILL section of this report. Placement and compaction of fill beneath slabs should be observed and tested by a representative of our office. 15 August 6,2009 KOECHLEIN CONSULTING ENGINEERS,INC. JobNo.09-033 Geotechnical and Materials Engineers EXTERIOR SLABS-ON-GRADE The subgrade at the proposed exterior slabs-on-grade elevations will consist of the sandy, silty clay,the existing fill, or the gravelly, sandy, clayey silt with scattered cobbles. Exterior slabs-on-grade constructed on the existing fill could have a high risk of differential movement. If the owner is willing to accept a high level of risk, then exterior slabs-on-grade may be constructed on a combination of existing fill and natural soils. If the owner would like to reduce the risk of movement to a low level, we recommend removing a minimum of 3 feet of the existing fill and replacing it with properly moisture conditioned and compacted new structural fill. Due to the fine-grained nature of the natural on-site soils, the possibility of frost heave in exterior slabs-on-grade is high. Proper drainage will help to reduce the risk of frost heave. It is our opinion that properly drained, natural soils will support the exterior slabs-on-grade with a low risk of movement. If the owner would like to reduce the risk of frost heave, we recommend that 3 feet of the natural, fine-grained soils be removed and replaced with properly moisture conditioned and compacted imported, granular fill. Regardless of which option is selected, we recommend the following precautions for the construction of exterior slabs-on-grade floors at this site: L If the owner is willing to accept a high risk of movement, than exterior slabs-on-grade may be placed on the existing fill. 16 � , August 6,2009 KOECHLEIN CONSULTING ENGINEERS,INC. JobNo.09-033 Geotechnical and Materials Engineers 2. If the owner would like to reduce the risk of movement to a low level, we recommend removing 3 feet of existing fill and replacing it with properly moisture conditioned and compacted new structural fill. 3. Proper drainage should be maintained to reduce the risk of frost heave. If the owner would like to further reduce the risk of frost heave in exterior slabs, we recommend that 3 feet of natural, fine-grained soils be removed and replaced with properly moisture conditioned and compacted imported, granular fill. 4. Exterior slabs-on-grade may be designed using a modulus of subgrade reaction of 90 psi/in. 5. Exterior slabs should be separated from the building. These slabs should be reinforced to function as independent units. Movement of these slabs should not be transmitted directly to the foundations or walls of the buildings. 6. Frequent control joints should be provided in all slabs to reduce problems associated with shrinkage of concrete. 7. Fill beneath exterior slabs-on-grades may consist of approved on-site soils or approved fill. Fill should be placed and compacted as recommended in the COMPACTED FILL section of this report. Placement and compaction of fill beneath slabs should be observed and tested by a representative of our office. FOUNDATION DRAINAGE Surface water, especially that originating from rain or snowmelt, tends to flow through relatively permeable backfill typically found adjacent to foundations. The water that flows through the fill collects on the surface of relatively impermeable soils occurring at the foundation elevation. Both this surface water and possible ground water can cause wet or moist below grade conditions after construction. 17 August 6,2009 KOECHLEIN CONSULTING ENGINEERS,INC. JobNo.09-033 Geotechnical and Materials Engineers It is our understanding that a portion of the proposed fire station will be constructed below grade. We recommend the installation of a drain along the below grade foundation walls. The drain should consist of a 4-inch diameter perforated pipe encased in free draining gravel and a manufactured wall drain. The drain should consist of a 4-inch diameter perforated pipe encased in free draining gravel. The gravel should have a maximum size of 1.5 inches and have a maacimum of 3 percent passing the No. 200 sieve. Washed concrete aggregate or screened rock will be satisfactory for the drainage layer. The drain should be sloped so that water flows to a sump where the water can be removed by pumping or to a positive gravity outlet. Recommended details for a typical wall drain are presented in the Typical Exterior Wall Drain Detail, Fig. 9. LATERAL WALL LOADS We anticipate that below grade walls, which require lateral earth pressures, will be constructed for this project. Lateral earth pressures depend on the type of backfill and the height and type of wall. Walls, which are free to rotate sufficiently to mobilize the strength of the backfill, should be designed to resist the "active" earth pressure condition. Walls that are restrained should be designed to resist the "at rest" earth pressure condition. The following table presents the lateral wall pressures that may be used for design. 18 August 6,2009 KOECHLEIN CONSULTING ENGINEERS,INC. JobNo.09-033 Geotechnical and Materials Engineers Earth Pressure Condition Equivalent Fluid Pressure c Active 40 At-rest 60 Passive 300 Notes: 1. Equivalent fluid pressures are for a horizontal backfill condition with no hydrostatic pressures or live loads. 2. A coefficient of friction of 0.3 may be used at the base of footings to resist lateral wall loads. Backfill placed behind or adjacent to foundation walls should be placed and compacted as recommended in the COMPACTED FILL section of this report. Placement and compaction of the fill should be observed and tested by a representative of our office. RETAINING WALLS We anticipate that the development of the site will require the construction of retaining walls. Foundation design criteria for the proposed retaining walls are presented in the FOUNDATIONS section of this report. Lateral earth loads for retaining wall designs are presented in the LATERAL WALL LOADS section of this report. In order to reduce the possibility of developing hydrostatic pressures behind retaining walls, a drain should be constructed adjacent to the walls. The drain may consist of a manufactured drain system and gravel. The gravel should have a maximum size of 1.5 inches and have a maximum of 3 percent passing the No. 200 sieve. Washed concrete aggregate will be satisfactory for the drainage layer. The manufactured drain should extend from the bottom of the retaining wall to within 2 feet of subgrade elevation. The water can be 19 August 6,2009 KOECHLEIN CONSULTING ENGINEERS,INC. JobNo.09-033 Geotechnica! and Materials Engineers drained by a perforated pipe with collection of the water at the bottom of the wall leading to a positive gravity outlet. A typical detail for a retaining wall drain is presented in the Typical Retaining Wall Drain Detail, Fig. 10. SURFACE DRAINAGE Reducing the wetting of structural soils can be achieved by carefully planned and maintained surface drainage. We recommend the following precautions be observed during construction and maintained at all times after the fire station is completed. 1. Wetting or drying of the open excavation should be minimized during construction. 2. All surface water should be directed away from the top and sides of the excavation during construction. 3. The ground surface surrounding the exterior of the fire station should be sloped to drain away from the building in all directions. We recommend a slope of at least 12 inches in the first 10 feet. 4. Hardscape (concrete and asphalt) should be sloped to drain away from the fire station. We recommend a slope of at least 2 percent for all hardscape within 10 feet of the fire station. 5. Backfill, especially around foundation walls, should be placed and compacted as recommended in the COMPACTED FILL section of this report. 6. Roof drains should discharge at least 10 feet away from foundation walls with drainage directed away from the fire station. 7. Surface drainage for this site should be designed by a Professional Civil Engineer. 20 August 6,2009 KOECHLEIN CONSULTING ENGINEERS,INC. JobNo.09-033 Geotechnical and Materials Engineers IRRIGATION = Irrigation systems installed next to foundation walls or sidewalks could cause ; consolidation of backfill below and adjacent to these areas. This can result in settling of exterior steps, patios, and/or sidewalks constructed on these soils. We recommend the following precautions be followed: 1. Do not install an irrigation system next to foundation walls. The irrigation ' system should be at least 10 feet away from the fire station. 2. Irrigation heads should be pointed away from the structure or in a manner that does not allow the spray to come within 5 feet of the fire station or the = face of the retaining walls. 3. The landscape around the irrigation system should be sloped so that no ponding occurs at the irrigation heads. 4. Install landscaping geotextile fabrics to inhibit growth of weeds and to allow normal moisture evaporation. We do not recommend the use of a plastic membrane to inhibit the growth of weeds. 5. Control valve boxes, for automatic irrigation systems, should be located at least 10 feet away from the structure and periodically checked for leaks and flooding. COMPACTED FILL Structural fill for this project may consist of approved the on-site sandy, silty clay the gravelly, sandy, clayey silt with scattered cobbles, the existing fill free of deleterious materials, or imported granular fill. The imported fill may consist of non-expansive silty or clayey sands or gravels with up to 30 percent passing the No. 200 sieve and a maximum plasticity index of 10. No cobbles or boulders larger than 10 inches should be 21 August 6,2009 KOECHLEIN CONSULTING ENGINEERS,INC. JobNo.09-033 Geotechnical and Materials Engineers placed in fill areas. Fill areas should be stripped of all vegetation and topsoil, scarified, and then compacted. Topsoil may be used in landscape areas. Fill should be placed in thin loose lifts then moisture treated and compacted as shown in the following table. The recommended compaction varies for the given use of the fill. Recommended Com action Percentage of the Percentage of the Use of Fill Standard Proctor Modified Proctor Maximum Dry Density Maximum Dry Density (ASTM D-698) (ASTM D-1557) Below Foundations 98 95 Below Slab-On-Grade Floors 95 90 Pavement Sub ade 95 AASHTO T99 90 AASHTO T180 Base Course 98 (AASHTO T99) 95 (AASHTO T180) Utili Trench Backfill 95 90 Backfill on-Structural 90 90 Notes: 1. For granular soils or non-expansive clay soils the moisture content should be —2 to +2 ercent of the o timum moisture content. We recommend that a representative from our office observe and test the placement and compaction of each lift placed for structural fill. Fill placed beneath foundations and slabs-on-grade is considered structural. It has been our experience that without engineering quality control, inappropriate construction techniques can occur which results in unsatisfactory foundation and slab performance. PAVEMENT DESIGN As part of the development of this site, a parking lot and access drive will be constructed adjacent to the proposed fire station. We anticipate that both flexible 22 August 6,2009 KOECHLEIN CONSULTING ENGINEERS,INC. JobNo.09-033 Geotechnica[ and Materials Engineers '" pavement and rigid pavement may be used for the construction of the proposed parking lot and access drive. It is recommended that rigid pavement be used in high traffic areas such as entrances or where heavy vehicles (fire trucks and trash trucks) turn or maneuver. The following sections present design assumptions and recommended flexible pavement sections for high and low traffic volume areas, as well as rigid pavement sections for high traffic volume areas. Flexible Pavement Desi�n The design of the flexible pavement sections was based upon an Equivalent Daily Load Application (EDLA), laboratory test results, and the Colorado Department of Transportation Pav�ment Design Manual. Design calculations for the access drive and parking lot were based on engineering soil characteristics from soil samples encountered in exploratory boring TH-1 to a depth of 5.0 feet. The subsurface conditions encountered in exploratory boring TH-1 consisted of 1.5 inches of asphalt underlain by 4 inches of roadbase. Below the roadbase, the subsurface conditions consisted of a tan, brown, slightly moist, medium dense, gravelly, sandy, clayey silt with scattered cobbles to the maximum depth explored of 12.0 feet. Laboratory test results indicated that the soils encountered within exploratory boring TH-1,to a depth of 5.0 feet, classify as A-4 soils, as defined by the AASHTO classification system. The pavement section designs presented in 23 August 6,2009 KOECHLEIN CONSULTING ENGINEERS,INC. JobNo.09-033 Geotechnica! and Materials Engineers this report are based on the subgrade soils classifying as A-4 soils. This soil type was assumed to have an Hveem Stabilometer R-value of 15. The R-value was estimated from the AASHTO classification of the soil. An EDLA was taken as 5 for low traffic and parking areas. An EDLA was taken as 50 for high traffic areas. Flexible pavement sections for the subject side are shown in the following table. Traffic Volume EDLA Full Depth Asphalt+Base Course Asphalt(inches) (inches) Low 5 5.5 4.0 +6.0 High 50 8.0 6.0+ 8.0 Flexible pavement design values and calculations are presented in the Pavement Design Calculations, Appendix A. Rigid Pavement Desi�n A rigid pavement section was designed using an EDLA value of 50 as used in the flexible pavement design. The subgrade soils were assumed to have a � modulus of subgrade reaction of 90 psi/in. The rigid pavement design is based on the working stress of the concrete, which is assumed to be 650 psi. The Colorado Department of Transportation Pavement Design Manual, along with the above mentioned design values, was used to determine a rigid pavement section. The rigid pavement design resulted in a design section of 7.0 inches of concrete. 24 August 6,2009 KOECHLEIN CONSULTING ENGINEERS,INC. JobNo.09-033 Geotechnical and Materials Engineers Pavement Materials The design of a pavement system is as much a function of the paving ' materials as the support characteristics of the subgrade. The quality of the construction materials is reflected by the structural coefficients used in the design calculations. If the pavement system is constructed of inferior materials, the life and serviceability will be substantially reduced. The asphalt component of the pavement is designed assuming at least 1,800 pounds Marshall stability (strength coefficient of 0.44). Normally, an asphalt aggregate should be relatively impermeable to moisture and should be designed as a well-graded mix. The oil content and voids ratio also need to be determined to verify compliance with the mix design. We recommend a job mix design be performed and periodic checks be made to verify compliance with the specifications for this project. All asphalt should be compacted to between 92 and 96 percent of the m�imum theoretical density. During asphalt placement, joints between asphalt rows should be feathered such that the surface water is shed from the asphalt surface. For a more thorough description of our pavement construction recommendations,please refer to Appendix B. 25 August 6,2009 KOECHLEIN CONSULTING ENGINEERS,INC. JobNo.09-033 Geotechnica! and Materials Engineers Subgrade Stabilization The fine-grained, natural on-site soils are highly susceptible to frost heave. Proper drainage will help to reduce the risk of frost heave. If the owner would like to further reduce the risk of early pavement deterioration due to frost heave, we recommend that 3 feet of the fine-grained, natural soils be removed and replaced with properly moisture conditioned and compacted imported granular fill. Based on our subsurface exploration, it is possible that existing fill could be encountered during the construction of the parking lot and access drive. Pavements constructed on existing fill may experience a shortened life expectancy. Movement of the pavement may result in cracking, high and low spots, and other distress. Repair of high and low spots and cracking in the pavements should be expected if pavements are constructed on the existing fill. If the owner is willing to accept the risk of premature deterioration of the pavements,then the flexible pavements may be constructed on the existing fill. If the owner would like to reduce the risk of early pavement deterioration due to the existing fill, we recommend that 3.0 feet of the existing fill be removed and replaced with a non-expansive structural fill. Construction of pavements on properly moisture conditioned and compacted non-expansive fill should experience a typical life expectancy, provided proper maintenance is provided. If 26 3 - August 6,2009 KOECHLEIN CONSULTING ENGINEERS,INC. JobNo.09-033 Geotechnical and Materia[s Engineers fill is required to obtain the final pavement subgrade elevation, the fill should consist of non-expansive material and be moisture treated and compacted as recommended in the COMPACTED FILL section of this report. Construction Considerations r Major utilities, such as water and sewer, are usually placed beneath g pavements during construction. If utilities are installed, the trench backfill should ` be observed, tested, and approved prior to paving. Careful attention should be paid to compaction of curb lines and around manholes. Excavation of completed pavements for utility construction and repair can destroy the integrity of the pavement and result in a severe decrease in serviceability. To restore the pavement to its original serviceability, careful control of backfill compaction and repaving is necessary. If utilities are to be installed beneath the proposed access drive or parking lot, the utilities should be installed,tested, and approved prior to paving. We do not anticipate that construction of the proposed parking lot and access drive will take place during cold weather. However, if plans change, caution should be employed when constructing during freezing times of the year. Construction on frozen subgrade soils may result in damage to the pavement. When the subgrade thaws, premature pavement failure may occur. Pavement or fill should be placed on unfrozen or frost-free subgrade soils. Frozen subgrade 27 ' August 6,2009 KOECHLEIN CONSULTING ENGINEERS,INC. JobNo.09-033 Geotechnical and Materials Engineers soils should be allowed to thaw or be removed and replaced to prevent future problems caused by the frozen subgrade. For a more thorough description of our pavement construction recommendations,please refer to Appendix B. Draina�e The primary cause of saturated subgrade soils and early pavement deterioration is water infiltration into the pavement system. The addition of moisture usually results in softening of the subgrade, potential frost heave, and the eventual failure of the pavement section. In order to reduce the risk of water infiltration below the pavement section and potential frost heave, we recommend that a surface drainage system be designed, constructed, and maintained in order to provide rapid removal of surface runoff. The design cross-slope should be maintained. If curb and gutter is installed, seals should be provided between curb and pavement and all joints to reduce moisture infiltration. LIMITATIONS Although the exploratory borings were located to obtain a reasonably accurate determination of subsurface conditions, variations in the subsurface conditions are always possible. Any variations that exist beneath the site generally become evident during excavation for the fire station. Therefore, we should be contacted by the contractor andlor owner so that a representative of our office can observe the completed excavation 28 � August 6,2009 KOECHLEIN CONSULTING ENGINEERS,INC. JobNo.09-033 Geotechnical and Materials Engineers to confirm that the soils are as indicated by the exploratory borings and to verify our foundation and floor slab-on-grade recommendations. The placement and compaction of fill, as well as installation of foundations, should also be observed and tested. The design criteria and subsurface data presented in this report are valid for 3 years provided that a representative from our office observes the site at that time and confirms that the site conditions are similar to the conditions presented in the SITE CONDITIONS section of this report and that the recommendations presented in this report are still applicable. We recommend that final plans and specifications for proposed construction be submitted to our office for study, prior to beginning construction, to determine compliance with the recommendations presented in this report and that the recommendations presented in this report are still applicable. 29 � August 6,2009 KOECHLEIN CONSULTINC ENGINEERS,INC. JobNo.09-033 Geotechnica! and Materials Engineers We appreciate the opportunity to provide this service. If we can be of further assistance in discussing the contents of this report or in analyses of the proposed structure from a geotechnical viewpoint, please contact our office. KOECHLEIN CONSULTING ENGINEERS, INC. Katie I. Shaw Engineer Reviewed by: Scott B. Myers, P.E. Senior Engineer (4 copies sent) 30 KOECHLEIN CONSULTING ENGINEERS,INC. Geotechnical and Materials Engineers �� r� a � � � �� � � � � r ����` � � - �� = �,�� � � �� � � �� �� �� 4 ' � � � : � w�sx wi� 4 :. �� �� ��� _ � ��� � � .�_� a` �: �*�� .�r ;� � � � ,� � �Q ,� ve�,°�,t� � � � � ��� `� � ��` � ��� (Generated from MapQuest on 8/6/09) SITE ! NOT TO SCALE VICINITY MAP JOB NO.09-033 FIG.1 KOECHLEIN CONSULTING ENGINEERS,INC. Geotechnical and Materials Engineers ; PROPOSED RETAINING �TH-1 WALL EXISTING RETAINING � WALL SYSTEM (`TYP.). �v � �� PROPOSED � °;���,�� WEST VAIL FIRE STATION ; � ,;\ ; TH-2• TH-3 �� �� PROPOSED p �RETAINING �p� WALL � � �� O� �� �� O� 1"= 50' � LOCATIONS OF EXPLORATORY BORINGS JOB NO.09-033 FIG.2 ¢ a KOECHLEIN CONSULTING ENGINEEF2S, INC. Geotechnical and Materials Engineers TH-1 `� 7930 APP.EL. 7929.0 TH-3 7930 TH-2 APP.EL. 7928.0 WC=10 APP.EL. 7927.0 •� -200=57 ,,, LL=24 ��� P1=5 WC=15 ��� -200=59 "' 7925 �•� 7925 13/12 "' ��� "' 11/12 �.� 14/12 ::: WC=19 ,,, -200=87 ��� LL=33 ��� PI=16 �.. 7920 �•• 7920 .�. .�. "' 10/12 .�. 50/7 26/12 "' WC=23 ��� DD=104 WC=16 %%% SW=0.0 DD=116 ��� ... .�. �.. 7915 — ••• �•• 7915 ... ��. ... �� — � 12/12 � 0 42�12 o m p p�' r lJJ W LL `� o < -- 7910 0 � 7910 � p o�°p 46/12 Z Q o 29/12 � w "� , m W 7905 � 7905 `'' 7900 7900 7895 7895 7890 7890 LOGS OF EXPLORATORY BORINGS JOB NO.09-033 FIG. 3 � KOECHLEIN CONSULTING ENGINEERS, INC. Geotechnical and Materials Engineers LEGEND: ■ ASPHALT � ROADBASE � SILT, Clayey, Sandy, Gravelly, Scattered cobbles, Slighly moist, Medium dense, Tan, Brown. � FILL, Clay, Sandy, Gravelly, Scattered cobbles, Organics, Moist, Stiff to very stiff, Black, Tan, Olive. "' CLAY, Silty, Sandy, Slightly moist to wet, Stiff, Brown, ... ��� Red brown. � GRAVEL, Lenses of fine sand, Scattered cobbles and boulders,Wet, Medium dense to dense, Red brown. = WATER. Indicates depth of water encountered while drilling. � BULK SAMPLE. Obtained from auger cuttings. � CALIFORNIA DRIVE SAMPLE. The symbol 50/7 indicates that 50 blows of a 140 pound hammer falling 30 inches were required to drive a 2.5 inch O.D. sampler 7 inches. Notes: 1. Exploratory borings were drilled on July 23, 2009 using a 4-inch diameter continuous flight power auger mounted on a track drill rig. 2. Ground water was encountered at the time of drilling in exploratory boring TH-2 at 11.5 feet and in exploratory boring TH-3 at 14.0 feet to the maximum depth explored of 20.0 feet. No ground water was encountered in exploratory boring TH-1 to the maximum depth explored of 12.0 feet. 3. The Logs of Exploratoy Borings are subject to the explanations, limitations, and conclusions as contained in this report. 4. Laboratory Test Results: WC- Indicates natural moisture content(%) DD- Indicates dry density(pcfl -200- Indicates percent passing the No. 200 sieve(%) LL- Indicates liquid limit(%) PI - Indicates plasticity index(%) SW- Indicates percent of swell-consolidation (%) 5.Approximate elevations are based on placing the locations of the exploratory borings on the topographic map provided by the Town of Vail and comparing the difference in elevations taken using a Stanley Compulevel Elevation Measurement System. LEGEND OF EXPLORATORY BORINGS JOB NO.09-033 FIG.4 � KOECHLEIN CONSULTING ENGINEERS ,00 0 90 ,0 80 ZO U` 70 30 m Z � _ u�i 60 40 m z a � � � 50 ,� w D � 40 � Z w m a 30 �o 0 _ zo eo �o � o �� 20o ioo �o � a.� o.a� o.00� DIAMETER OF PARTICLE IN MM +75 MM GRAVEL SAND SILT CLAY Sample of SILT,Sandy,Gravelly GRAVEL 19 % SAND 24 % Sou�ce TH-1 Sample No. EIev./Depth 0.5-5.0 feet SILT&CLAY 57 % LIQUID LIMIT 24 % PLASTICITY INDEX 5 % 100 0 gp 10 80 ZD 70 � � z r" � v�i 60 40 m z � 50 `� � W � � qp 60 Z w m d 30 �p O 20 80 10 � p 100 200 100 10 1 0.1 0.01 0.001 DIAMETER OF PARTICLE IN MM +75 MM GRAVEL SAND SILT CLAY Sample of FILL,Clay,Sandy,Gravelly GRAVEL 11 % SAND 30 % Source TH-2 Sample No. Elev./Depth 0.5-5..0 feet SILT&CLAY 59 % LIQUID LIMIT % PLASTICITY INDEX % GRADATION TEST RESULTS y Job No. 09-033 FIG.5 KOECHLEIN CONSULTING ENGINEERS ,� - o � ,o E� 20 � 70 30 � Z m � u�i60 40m a � F 5o s° � w � � 40 60 D W Z m � 30 �o ° zo ao �o so o �oo zoo �oo �o � o.i a.o� o.00� DIAMETER OF PARTICLE IN MM +75 MM GRAVEL SAND SILT CLAY Sample of CLAY,Silty,Sandy GRAVEL 0 % SAND 13 % Source TH-3 Sample No. EIev./Depth 4.0 feet SILT 8 CLAY 87 % LIQUID LIMIT 33 % PLASTICITY INDEX 16 % Sample of GRAVEL % SAND % Source Sample No. Elev./Depth SILT&CLAY % LIQUID LIMIT % PLASTICITY INDEX % GRADATION TEST RESULTS Job No. 09-033 FIG.6 : � � • KOECHLEIN CONSULTING ENGINEERS -1 � 0 1 2 WATER ADDED 3 c '�p � c 4 c� a`> a ' i 5 � 6 ; 7 8 k' 9 .1 2 .5 1 2 5 10 20 � Pressure,p,ksf Sample of CLAY,Silty,Sandy Natural Dry Unit Weight= 104.1 (pc� Source TH-3 Sample No. EIev./Depth 9.0 feet Natural Moisture Content= 23 % SWELL-CONSOLIDATION TEST RESULTS Job No. 09-033 FIG.7 KOECHLEIN CONSULTING ENGINEERS,INC. Geotechnical and Materials Engineers CONCRETE FOOTING '��I 1= ' - �� EXISTING �� \I� EXISTING FILL COMPACTED FILL FILL � (SEE REPORT FOR � COMPACTION RECOMMENDATIONS) _������—���—���—���= '��—iTi—���—_ � _I I I—I I I—i i� FIRM NATURAL SOIL EDGE OF EXCAVATION (EXCAVATE AS PER OSHA REGULATIONS) FOUNDATION EXCAVATION RECOMMENDATIONS JOB NO.09-033 FIG.8 � KOECHLEIN CONSULTING ENGINEERS,INC. Geotechnical and Materials Engineers CIAYEY BACKFILL �� - � � - - - _lu'II I— _ _— — �II�� COMPACTED BACKFILL BELOW GRADE WALL EDGE OF EXCAVATION (EXCAVATE AS PER OSHA REGULATIONS) MANUFACTURED WALL DRAIN� � ' WATERPROOFING � OR DAMPPROOFING � � � � FILTER FABRIC � GRAVEL 12" PLASTIC SHEETING F-�F-12"MIN. PERFORATED PIPE NOTES: 1. DRAIN SHOULD BE AT LEAST 12 INCHES BELOW TOP OF FOOTING AT THE � HIGHEST POINT AND SLOPE DOWNWARD TO A POSITIVE GRAVITY OUTLET OR £ TO A SUMP WHERE WATER CAN BE REMOVED BY PUMPING. � � 2. EXCAVATIONS ADJACENT TO FOOTINGS SHOULD BE CUT AT A 1 TO 1 (HORIZONTAL TO VERTICAL)OR FLATTER SLOPE FROM THE BOTTOM OF THE FOOTINGS. EXCAVATIONS ADJACENT TO FOOTINGS SHOULD NOT BE CUT VERTICALLY. 3. THE DRAIN SHOULD BE LAID ON A SLOPE RANGING BETWEEN 1/8 INCH AND 1/4 INCH DROP PER FOOT OF DRAIN. 4. GRAVEL SPECIFICATIONS: WASHED 1.5 INCH TO NO.4 GRAVEL WITH LESS THAN 3%PASSING THE NO.200 SIEVE. 5. THE BELOW GRADE CONCRETE FOUNDATION WALLS SHOULD BE PROTECTED FROM MOISTURE INFILTRATION BY APPLYING A SPRAYED ON MASTIC WATERPROOFING,DAMPPROOFING,OR AN EQUIVALENT PROTECTION METHOD. TYPICAL EXTERIOR WALL DRAIN DETAIL � JOB NO. 09-033 FIG. 9 KOECHLEIN CONSULTING ENGINEERS,INC. Geotechnical and Materials Engineers CLAYEY BACKFILL 10 _ � � - - - - - - MANUFACTURED � � -_ - WALL DRAIN � -�� COMPACTED BACKFILL RETAINING WALL EDGE OF EXCAVATION (EXCAVATE AS PER OSHA REGULATIONS) WATERPROOFING OR DAMPROOFING FILTER FAB C GRA EL 0 PERFORATED PIPE NOTES: 1. DRAIN SHOULD BE SLOPED DOWNWARD TO A POSITIVE GRAVITY OUTLET OR TO A SUMP WHERE WATER CAN BE REMOVED BY PUMPING. 2. THE DRAIN SHOULD BE LAID ON A SLOPE RANGING BETWEEN 1/8 INCH AND 1/4 INCH DROP PER FOOT OF DRAIN. 3. GRAVEL SPECIFICATIONS: WASHED 1.51NCH TO NO.4 GRAVEL WITH LESS THAN 3%PASSING THE NO.200 SIEVE. 4. THE BELOW GRADE CONCRETE RETAINING WALLS SHOULD BE PROTECTED FROM MOISTURE INFILTRATION BY APPLYING A SPRAYED ON MASTIC WATERPROOFING OR AN EQUIVALENT PROTECTION METHOD. TYPICAL RETAINING WALL DRAIN DETAIL JOB NO.09-033 FIG.10 SUMMARY OF LABORATORY TEST RESULTS TABLEI . . . . . . ' �• • � . �. . . � • � � � � ' • � � � � �� ��� � � � . � � � � 0������00 , � . ����� ���� � ' ' ��� ���� . , � ' ' ��� ���� . , ����� ���� ����� � ��-- . , ��0�� � . , ����� ���� ����� ���� ����� ���� ����� ���� ����� ���� ����� ���� ����� ���� ����� ���� ����� ���� ����� ���� ����� ���� ����� ���� ����� ���� ����� ���� ����� 0��� ����� ���� ����� ���� ����� ���� ����� ���� JOB NO.09-033 KOECHLEIN CONSULTING ENGINEERS, INC. August 6,2009 KOECHLEIN CONSULTING ENGINEERS,INC. JobNo.09-033 Geotechnica! and Materials Engineers APPENDIX A PAVEMENT DESIGN CALCULATIONS � KOECHLEIN CONSULTING ENGINEERS,INC. Geotechnical and Materials Engineers FLEXIBLE PAVEMENT DESIGN DATA—LOW EDLA DESIGN DATA Traffic Load-EDLA = 5 Traffic Load- 18 kip ESAL's = 36,500 Design Life = 20 Subgrade Soil Classification = A-4 Assumed"R" Value = 15 Soil Support Value-S, = 3.9 Resilient Modulus-MR(psi) = 4,195 Reliability-R(%) = 90 Serviceability Index-SI = 2.0 Serviceability Loss-PSI = 2.5 Overall Deviation- So = 0.44 DESIGN CALCULATION RESULTS Based on the following equation: log,o(18k ESAL)=ZRxSo+9.36xlog�o(SN+1)-0.20 +log,o(PSI/(4.2-1.5))/(0.4+(1094/(SN+I)519))+2.32xlog,o(MR)-8.07 � Structural Number-SN = 2.4 PAVEMENT THICKNESS DESIGN EQUATION SN=C�D1+CZDzmz where C, =Strength Coefficient-Asphalt = 0.44 CZ=Strength Coefficient—Aggregate Base Course = 0.12 mz=Drainage Coefficient = 1.0 D, =Depth of Asphalt(inches) DZ=Depth of Roadbase (inches) PAVEMENT THICKNESS RESULTS Full Depth Asphalt Thickness D, = 5.5 inches Asphalt+Aggregate Base Course Di(Asphalt) = 4.0 inches DZ(Aggregate Base Course) = 6.0 inches � JOB NO. 09-033 FIG.A-1 KOECHLEIN CONSULTING ENCINEERS,INC. Geotechnica! and Materials Engineers FLEXIBLE PAVEMENT DESIGN DATA—HIGH EDLA DESIGN DATA Traffic Load-EDLA = 50 Traffic Load- 18 kip ESAL's = 365,000 Design Life = 20 Subgrade Soil Classification = A-4 Assumed"R" Value = 15 Soil Support Value-S, = 3.9 Resilient Modulus-MR(psi) = 4,195 Reliability-R(%) = 90 Serviceability Index-SI = 2.0 Serviceability Loss-PSI = 2.5 Overall Deviation-So = 0.44 DESIGN CALCULATION RESULTS Based on the following equation: log,o(18k ESAL)=ZRxSo+9.36xlog,o(SN+1)-0.20 +loglo(PSU(4.2-1.5))/(0.4+(1094/(SN+1)519))+2.32xlog,o(MR)-8.07 Structural Number-SN = 3.4 PAVEMENT THICKNESS DESIGN EQUATION SN=C�D�+CZD2m2 where C, =Strength Coefficient-Asphalt = 0.44 Cz=Strength Coefficient—Aggregate Base Course = 0.12 m2=Drainage Coefficient = 1.0 D1 =Depth of Asphalt(inches) DZ=Depth of Roadbase (inches) PAVEMENT THICKNESS RESULTS Full Depth Asphalt Thickness D� = 8.0 inches Asphalt+A�re�ate Base Course D,(Asphalt) = 6.0 inches DZ(Aggregate Base Course) = 8.0 inches JOB NO.09-033 FIG.A-2 � s KOECHLEIN CONSULTING ENGINEERS,INC. Geotechnical and Materials Engineers RIGID PAVEMENT DESIGN DATA DESIGN DATA Traffic Load-EDLA = 50 Traffic Load- 18 kip ESAL's = 365,000 Design Life = 20 Subgrade Soil Classification = A-4 Assumed Modulus of Subgrade Reaction-k(psi/in) = 90 Modulus of Rupture-S'c(psi) = 650 Modulus of Elasticity-Ec(psi) = 3,400,000 Drainage Coefficient-Cd = 1.0 Load Transfer Coefficient-J = 4.2 Reliability-R(%) = 90 Serviceability Index-SI = 2.0 Overall Deviation- So = 034 DESIGN CALCULATION RESULTS Based on the following equation: log�o(18k ESAL)=ZRxSa+7.35xlog,o(D+1)-0.60+log,o(PSU(4.5- 1.5))/(1.0+(1.624x10')/(D+1�8.46��+�4.22-0.32xp,)x(loglo[(S�xCnx(Do.�s_ 1.132))/((215.63xJx(Do's-(18.42/(E�/k)o.zs))))� PAVEMENT THICKNESS RESULTS Rigid Pavement Thickness D = 7.0 inches JOB NO. 09-033 FIG.A-3 August 6,2009 KOECHLEIN CONSULTING ENGINEERS,INC. JobNo.09-033 Geotechnica! and Materials Engineers APPENDIX B PAVEMENT CONSTRUCTION RECOMMENDATIONS fi � KOECHLEIN CONSULTING ENGINEERS,INC. Ceotechnical and Materials Engineers FLEXIBLE PAVEMENT CONSTRUCTION RECOMMENDATIONS Experience has shown that construction methods can have a significant influence on the life and serviceability of a pavement system. We recommend the proposed pavement be constructed in the following manner: 1. Where the subgrade soils do not satisfy the compaction requirements, they should be scarified, moisture treated, and recompacted. Soils should be compacted as specified in the COMPACTED FILL section of this report. 2. Utility trenches and all subsequently placed fill should be properly compacted and tested prior to paving. Fill should be compacted as specified in the COMPACTED FILL section of this report. � 3. After final subgrade elevation has been reached and the subgrade compacted, the area should be proof-rolled with a heavy pneumatic tired vehicle (i.e., a loaded 10-wheel dump truck). Subgrade that is pumping or deforming excessively should be removed and replaced. 4. If areas of soft or wet subgrade are encountered, the material should be overexcavated and replaced. Suitable structural fill may be used. Where extensively soft,yielding subgrade is encountered,we recommend the excavation be inspected by a representative of our office. 5. Aggregate base course should be laid in loose lifts not exceeding 6.0 inches, moisture treated to within 2.0 percent of the optimum moisture content, and compacted as specified in the COMPACTED FILL section of this report. 6. The aggregate base course may consist of processed recycled asphalt. The recycled asphalt base course should meet the gradation requirements of CDOT Class 5 or Class 6 base course. The recycled asphalt base should be laid in loose lifts not exceeding 6.0 inches, moisture treated and compacted as specified in the COMPACTED FILL section of this report. 7. Asphaltic concrete should be plant-mixed material. Superpave material should be compacted to between 92 and 96 percent of the maximum theoretical density and other asphalt material to at least 95 percent of the maximum Marshall value. 8. The subgrade preparation and the placement and compaction of all pavement layers should be observed and tested. Compaction criteria should be met prior to the placement of the next paving lift. JOB NO.09-033 FIG. B-1 ? , . KOECHLEIN CONSULTING ENGINEERS,INC. Ceotechnica! and Materials Engineers RIGID PAVEMENT CONSTRUCTION RECOMMENDATIONS Rigid pavement sections are not as sensitive to subgrade support characteristics as flexible pavement. Due to the strength of the concrete, wheel loads from traffic are distributed over a large area and the resulting subgrade stresses are relatively low. The critical factors influencing the performance of a rigid pavement are the strength and quality of the concrete, and the uniformity of the subgrade. We recommend subgrade preparation and construction of the rigid pavement section be completed in accordance with the following recommendations. 1. Where the subgrade soils do not satisfy the compaction requirements, they should be scarified, moisture treated, and compacted. Soils should be compacted as specified in the COMPACTED FILL section of this report. 2. Utility trenches and all subsequently placed fill should be properly compacted and tested prior to paving. Fill should be compacted as specified in the COMPACTED FILL section of this report. 3. The resulting subgrade should be checked for uniformity and all soft or yielding materials should be replaced prior to paving. This should be done by proof-rolling with a heavy pneumatic tired vehicle (i.e., a loaded 10-wheel dump truck). Concrete should not be placed on soft, spongy, frozen, or otherwise unsuitable subgrade. 4. Subgrade should be kept moist prior to paving. 5. Curing procedures should protect the concrete against moisture loss, rapid temperature change, freezing, and mechanical injury for at least 3 days after placement. Traffic should not be allowed on the pavement for at least one week. 6. A white, liquid membrane curing compound, applied at the rate recommended by the manufacturer, should be used. 7. Construction joints, including longitudinal joints and transverse joints, should be formed during construction or should be sawed shortly after the concrete has begun to set, but prior to uncontrolled cracking. All joints should be sealed. 8. Construction control and inspection should be carried out during the subgrade preparation and paving procedures. Concrete should be carefully monitored for quality control. JOB NO.09-033 FIG. B-2