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Home My WebLink AboutB14-0096 CR2 Retaining wall letter K R M CONSULTANTS INC. , RECORD P.O.Box 4572 • Vail,Colarac[o 81658 • 970-9�F9-9391 TO: Seth Bassung � lntention Architecture � � � a 1 � i DATE: 6/3/2014 JOB NUMBER: 1402-06 � r PROJECT.• Snowberry Duplex � � � � ❑ RFI ❑ MEETING NOTES � RESPONSE ❑ CLARIFICAT/ON/CHANGE � � � � This letter is to acidress the design a�d consideratians of the retaining wa[!s around the perimeter of the e above mentioned praject. w i The residence is f�uilt into a steep slope and as a result requires a series of tiered re�aining walls on both � sides of the structure. �`hese retaining walls vary in height from 2' ta 6' abo�e grade. The distance t between the waEls varies from 4' ta 'I2'. The slopes between the base of one wall to the top of the � adjacent wall varies from 7:$ to 1:2. The number of walls within the tiered system varies and is based on r arc�itectural sheet A1.1, s ; � E The soil at these retaining walls is reinforced using a geogrid material. To evaluate t�e geogrid, we used � . the Keystone Retaining wall program. The results of these calculations are attached. ` ! �fhere is an existing water tank on the adjacent lot. This tank is in a location that will not result in any � surcharge that will affect the retaining walls or structure. ? 1 ; f'lease contact us with any questions you may have. ; i � � E SIGNED: COPY TO: � � � i � Joe . alley, � � �"� ' i � � � i.�.. 1�.' � �e�aa�,.":;'� � O�O t-I'.;r,r.;"��''\ REVIEW . �,�,��`o ;��r�naC,y;1 i �:, ° c �s P? � � f.. E E Tir� D, Hennum, PE ;>°oo W�"�� 0� _ �o :�_ E �,�,SI��`!f�,t.�'`� ,' ,� - - ��'` J U�i�` '-°�3�� 2014 � � ! I ` STONE � RETNhIHGWAl,1.5Y5TEMS RETAINING WALL DESIGN KeyWall_2012 Version 3.7.2 Build 10 Proj�t:S'nowberryDuplex Date• b/3/.2014 Proj�t No: 1402-Ob Designer:J'MO Case�Case 1 Des��Method: Rankine-w/Batter(modified soil interface) � Des� Parameters ---- -- � i Soii parameters: de c nsf Y pcf ° � n'n. r � i ,,.�' Reinforced Fill 28 0 110 = �� , r �Y I Retained Zone 28 D 110 ��}��-�-� Foundation Soil 28 0 110 """'""'- Reinforced FiU Type: Sand, Silt or Clay Unit lFill: Crushed Stone, 1 inch minus Min.imum Desxgn Factors of Safet� sliding: 1.50 puIlout: 1.50 uncertainties: 1.50 overtuzning: 2.40 shear: 1.50 cannection: 1.50 ; bearing: 2.00 bending: 1.50 � Desi�o Preferences � 6 f � Reinforcing Pararr�eters:Strata-Grid Geogrids � Tult RFcr RFd RFid LTDS FS Tal Ci Cds � � SGl SQ 1875 1.65 1.10 1.10 939 I.30 b26 0.80 0.80 , Analysis: Case:Case 1 � New Case ° Unit Type: Compac/120.00,pcf Wall Batter:0,00 deg(Hinge Ht N/A) � Leveling Pad: Ct-ushed Stone � Wall Ht: 7.00ft embedment: 1.00 ft � BackSlope: 22.50 deg.slope, 12.00 ft long 3 Surcharge: LL:0 psf uniform surcharge DL: 0 psf uniform surcharge � Load Width: 100.00 ft .�oad Width:IOQ.DO ft � 6 � Results: Slirling Overtur�in� Bearin� Shear Behdin� E Factors ofSafety: 1.53 3.08 4.36 S.S8 2.50 � � CaIculated Bearing Pressure: .1.271/1271 psf 3 Eccentricity at base:0.6I ft �i Reinforcing:(ft&lbs/ft) d Calc. Allow Ten Pk Conn Pullout L_a�eK Hei�ht Le. n�th Tension Reinf.'�ype Tal TcI FS ' 4 5.33 S.S 185 SGISO 626 ok 422 ok 2.14 ok � 3 3.33 S.S 303 SG1S0 b26 ok 481 ok 3.87 ok 2 2.00 5.5 346 SGl SO 626 ok 521 ok S.SI ok � 1 O.G7 S.S �F36 SGI SO 626 ok 553 ok 6.46 ok � Reinforcing Quantities(no waste included): � SGl SO 2.44 sy/ft � NOTE: 7'HESE C�4LCUL�(TIONSARE F4R PRELIMINARYDES.lGN ONLYAND SHOULD �� NQT BE USED FOR CONS7'R UC�.ION WITHOUT 1�ET�IEWBYA QUALIFIED ENGINEER � l�ate 6/3/2014 Case 1 Page 1 � i E DETA�LED CALCULATIONS Pra��t:Snowberry Duple,r Date: G/3/2014 ProJ�t No: 1402-06 ' Designer:J'MO Cas��Case 1 Des3�Method:Rankine-w/Batter(modified soil interface) Soi� pararneters: de C p5f y �cf Reinforced Fill 28 0 I10 Retained Zone 28 0 !10 � Foundation Soil 28 0 11 D Le��ling Pad: Crushed.stone � Mod=+Iar Concrete Unit: Compac u Deptb;1,00 ft In-Place Wt: I20 pcf � � Geaxnetry = Internal Stability External Stabi7iry h (Broken geometry) (Broken geo,netry) � Height: 7.00 ft Height:8.86 ft x BackSlope: � Angle: 22.5 deg Angle:22.5 deg � Height: 497 ft Height:3.11 ft 3 Batter: O.00deg Batter: O.00deg � Surcharge: � Dead Load:0.00 psf Dead Load: 0.DO psf � .Live Load: 0.00 psf Live Load:0.00 psf ; Base width:S.S ft Earth Pressures: � i � � � � � f � k - ��4a*�� 2- � 1 sin��-�'��'—� � � sir�� a s�xs��--S� 1�- �-� sEn��—S��i�r,�cz-F,i3� :�: � H�'� �.�..:� �' � � � � � � Internal Externa � � = 28 deg � = 28 deg � a =90.00 deg a =90.00 deg (3 =22.50 deg f3 =22.50 deg � S = 19.55 deg S = 19.31 deg ' H = 7.00 ft lca =0.49b ka =0.463 Hinge Height: Hinge H�Not applicable � � � � �ate 6/3/2014 Case 1 Page 2 i Rei�orcing Parameters:Strata-Grfd Geogrids Tult RFcr RFd RFid LTDS FS Tal Ci Cds SGt s� 1875 1.65 1.10 1.10 939 1.50 626 0.80 D.80 Co��ction Parameters:Strata-Grid Geogrirls Frictionall Break Pt Frictional 2 SGI50 Tcl=Ntan{20.20) -�560 657 Tcl=Ntan(I5.00) +626 � s Uni.t Shear Data � Sheat'=Ntan{40.00) f Inter-Unit ShearShear=Ntan(26.90) + 769.00 - � ;, Calculated Reactions ° For �he"modified"design method, the back of the mass assumed to be vertical for caiculation of resisting forces. effeCtive slidang length =5.50 ft � � , � i �� w.�....�.,, . T'�=0.3H-��-H�ka— 2c-�ce� P,�:= q•H•ka `s ..�'-,.�.��"`. �s�;�a`" ; � � � P�:= I'�•ccrs�S� P�,:= P�cas�S� �' s � �as,�as� g �'�4,�= Ps•sin�d'J P�:= Pq sin.�&� � �,�� '�� § � �� w� � �a � �r� F ; �_ � i Reactions are: `'�"`� ' � Area Force Aa-r�n-x Arm-y Moment ' wl s�o.00 �o.soo� 3.soo �20.00 � W3 3465.00 (3.250] 3.500 I126I.ZS � WS 461.33 (4.00DJ 7.621 1845.32 � � Pa h 1886.93 S.SDO �2.955�j -SS75.22 � Pa v 661.32 �S.SDO�j 2.955 3637.27 Sum U= 5427:65 Sum Mr= 17163.84 � Surn H= .1886.93 Sum Mo= -557522 3 II I � � i f 1 i Date 6I3/2014 Case 1 Page 3 iI i Ca1��1�te Sliding atBase For Sliding,Vertical Force=W 1+W2+W3+W4+WSa-W6�qd =5428 The resisting force withiva the rein.mass,Rf 1 =N tan(2$} =288b The resisting force at the fowndation,Rf 2 =N tan{28.OU) =2886 The c�riving forces,Df,are the suzx�of the external earth pressures: � Pa h+Pql_h f Pqd h = 1887 tY�e�actor of Safety for Sliding is Rf 21Df = 1.53 9 Calculate Overturnin�: � Overturning moment:Mo�Sum Mo =-SS75 ` Resistix�g moment:Mr=Sum Mr = 17 T 64 � Factor of Safety of Qaez�z�iaxg:Mr/Mo =3.08 ' 6p B B2 N E �{ 4 i i [ �p t t � I 1 A P 6 � f � � � 3f t � � E E f � � � j] 3 1 � I � i € � ! [ � 1 f I` IE ! E E Date 613J2014 Case I Page 4 � CaL�late eccentricity at base: with Surcharge/withoat Sarcharge Su�Moments = 11589/11589 Suz��Iertical=5428/5428 Bas�Length=5.50 e= ��615/0.615 � � Cal cuiate LJ��imate Bearing based on shear: � wh��: � Nq= 14.72 Nc=25.80 Ng= 16.72(ref.Vesic(1973, 1975)eqns) � Qult=5545 psf '; Equ.ivalant footi�ng widtxz,B'=L-2e=4.27/4.27 � Bea�inig pressure=sumVB'= 1271 psf/1271 psf [bearing is greatest without iiveload] � Factor of Safety£or bearuig=Qultlbearing=436 � � Calculate Tensions in Reinforcing: � The tensions in the reinforcing layer,and the assumed load at the connection, � i is the vertical azea suppozted by each respective Iayer,Sv.Column[7]is'2c sqrt(ka)'. � � Table of Results ppf � L;] [2l [3l [4] Lsl L6l [�] L8] [9l L141 Llll � Y.aver Deptlx zi h� ka/rho 1?a (Pas+Pasd� c (S+b}cos(d)-7 Ti Tcl Tsc j 4 1.67 I33 0.501/43 196 0 0 i 85 1&5 422 N/A � 3 3.G7 3.50 0.501/43 32T 0 0 303 303 481 NIA � 2 5.00 5.00 0.501/44 367 0 0 346 346 521 N/A � 1 6.33 6.33 0.499/44 453 0 0 436 436 553 N/A � ; Calculafe sliding on t#�e reinforcing: � The shear vaIue is the lessor of base-shear or i�ter-unit shear. � I�] [2] [3] C4] I57 [6] [�l [8] [g] [��l [�1] [Z2] _I.aver Depth zi N Li Cds �r RF ka Pa Pas+pasd DF FS i 4 1.b7 1400 4.50 0.80 870 1466 0.501 343 0 324 4.52 � 3 3.b7 2550 4.50 0.80 992 2077 0.493 829 0 782 2.66 j 2 5.00 3348 4.50 0.80 1073 2498 0.481 I246 0 1175 2.I2 I 1 6.33 4169 �.SO 0.80 rrss 2928 0.468 1731 0 1633 1.79 i 3 i i i � E i( f f � � � 3 3 i � I II i � E Date 6/3/2014 Case 1 Page 5 3 i Cal��late prillout of each layer The �'oS(R*IS*)of pullout is calculated as t1�e inc�ividual lay��'pullout(R�divided by tlze tension(D fl in that layer. The �gle of the failure plane is:31.00 degrees from vert�icat. L1J L2l [3] C47 Lsl [6] L7l L8l Laver Depth zi Le SumV Ci POi Ti FS PO 4 1.67 1.30 465 0.80 395 185 2.14 ; 3 3.67 2.50 1377 0.80 1172 303 3.87 � 2 5.00 3.30 2242 0.80 1908 34G S.SI ; I 6.33 4.10 3314 0.80 2819 436 6.46 � � � Che�k Shear&Bending at each layer ? � � Bendurg on the top layer is the FOS of overturning of the Units � (Mosrsurcharge loads need to be moved backfrom the face.) � J i � �1] �2] �3] �4] �S] C6] ��1 �8] �9] La� De�h zi Si DM Pv RNI FS b DS R�S FS Sh # 4 1.67 1.67 40 2Q0 ,100 2.SO 72 870 12.07 � 3 3.b7 2.00 78 320 273 3.51 164 991 6.03 � 2 5.00 1.33 53 520 387 7.36 1 bl 1073 6.65 = 1 G.33 I.33 68 680 493 7.28 207 11 SS .5.S8 i , 3 � i i � � i � � � � r � ➢ 1 � � �i f 1 I d Ef { f f f � � � i i I ! !€ € I � i � l Date 613l2014 Case 1 Page 6 I