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Home My WebLink Aboutm29053 finalti S. E. Modall & Associates, Inc. Consultants in the Earth Sciences f 3030 South Bundy Drive, Los Angeles, Californla90066. 2131390-4079 1 2168 South Hathaway Street, Santa Ana. California92705 • 7141546-6602 ADDENDUM REPORT FOR TWICTS 29053, 34160 AND 34161 DIAMOND BAR COUNTY OF LDS ANGELES, CALIFORNIA for WEATHERFIELD HOMES W. O. 605D May 5, 1978 S. E. Medall & Associates, Inc. Consultants in the Earth Sciences 3030 South Bundy Drive, Los Angeles, California 90066.2131390.4079 2168 South Hathaway Street, Santa Ana, California92705 •714/546.6602 May 5, 1978 W. 0. 605D Santa Ana Weatherfield Homes 2130 E. 4th Street Suite 110 Santa Ana, California 92705 Attention: Mr. A. S. Brengle Subject: Addendum Report for Tracts 29053, 34160 and 34161, Diamond Bar, County of Los Angeles, California. References: 1) Supplemental Soils Engineering and Geologic Investigation and Grading Plan Review, Tracts 29053, 34161 and 34160, dated December 19, 1977. 2) Response to Sail Engineering Section Review Sheet, dated February 6:i 1978, Tracts 34160, 34161 (Parent Tract 29053), Diamond Bar Area, County of Los Angeles, dated February 20, 1978. 3) Supplemental Subsurface Exploration, Tracts 29053, 34160, 34161, Diamond Bar, County of Los Angeles, California, dated March 7, 1978. 4) Response to the Geology Appeal Board for the County of Los Angeles, Tracts 29053, 34160 and 34161, Diamond Bar, California, for the County of Los Angeles, dated March 20, 1978. 5) Addendum Comments regarding Soil Engineering Report, dated February 20, 1978, Tracts 34160, 34161, Diamond Bar Area, County of Los Angeles, California, dated March 23, 1978. Weatherfield Homes Page 2 Gentlemen: May 5, 1978 W. O. 605D 6) Comments on Questions Raised by Mr. Dave Popplar regarding Tracts 29053, 34160, 34161, Diamond Bar, County of Los Angeles, California, dated March 23, 1978. 7) Tract 29053, 34161 and 34161, Reply to the County of Los Angeles Geologic Review Sheets, dated February 1, 1978 and February 22, 1978, dated March 24, 1978. The following report is our response to the Geologic Review Sheet dated April 24, 1978, prepared by Mr. David Popplar, Engineering Geology Section and Mr. Charles Sudduth, Soils Engineering Section, Department of County Engineer, County of Los Angeles (copy attached). Our responses are keyed to each County comment. Item Al (i) : (review 'of March 2'0, 1978 report) : During conduct of the investigations by our office and by others, we have considered the possibility that landslides of various sizes existed at several locations within the limits of the subject contiguous tracts. These were considered during planning for our investigations and in evaluating the results. At one time, it was hypothesized that the entire property was situated on the erosion -directed remains of a landslide so massive and so much modified by erosion that its existence had not been 3. '. Hadall & Associates, Inc. Weatherfield Homes Page 3 May 5, 1978 W. O. 605D recognized. This hypothesis was evaluated by advancing seven deep exploratory borings at locations selected so as to yield definitive evidence of the existence or non-existence of such a slide. Our investigation provided evidence to support the conclusion that several landslides to exist; these are presented on our. Geologic Map. However, the results also provided evidence that other hypothesized landslides, in including the "massive landslide", do not exist. In summary, all recognized landslides are shown on our Geologic Map. We believe that all significant geologic conditions needed for evaluation of the proposed construction have been identified and that appropriate remedial action has been recommended, either proviously, or in this letter. Again, we reiterate, that we believe that the subject tract is underlain only by the landslides or landslide debris shown on the grading plan and geologic map. Item A2 (i) a: (review 'of March '23, 1978' report) : Section M--M'--M" (Plate IIIB) has been extended downslope through Boring 15. The fills proposed on Lots 71-77 will not be sliver fills, but will be placed with a minimum width (15 feet) benched S. E. Medall & Associates, Inc. Weatherfield Homes Page 4 and keyed into the underlying bedrock. May 5, 1978 W. O. 605D This is an accepted professional standard of practice and it is included in our "Standard Grading Specifications". A calculation for this 15--foot wide fill is attached (Plate la-1f). The area upslope of this fill does not surcharge these slopes inasmuch as recommended uphill key will be placed at depths sufficient to intersect beddings which run below the lower fill keys. The cut-off depth for the buttress design above the cul-de-sac street (Grayfield Lane) has been discussed previously in our March 24, 1978 report. We stated, therein, that the uphill cut-off selected for the sliding block section was computed on the basis of the "critical height",.dc as defined in the expression: G do = cost c (1.5 tangy-tanO) Where c = cohesion = 200 lbs/ft2 density = 120 lbs/ft2 dip angle of internal friction = 100 1.5 = factor of safety Furthermore, the attitude reversals and faults uphill from the buttress tend to limit the "driving mass" to that used by us S. E. Madell & associates, Inc. Weatherfield Homes May 5, 1978 Page 5 W. O. 605D to design the buttress. The design has been modified (Plates 2a-2f) and this modification has been shown on the grading plan. Item A2(i)b. Section E-El (Plate IIIA) has been revised to include the buttress as well as the hypothesized "massive landslide". Item A3. ' The county acknowledges receipt of reports from Douglas Moran, Consultant, and our reports regarding potential landslides on the tracts. Apparently these reports have been accepted by the County. Item Bl (review 'of March 24, 1978 report) : The initial county comments have been discussed above (Items Al and A2). Item B 2 ( review item 3, dated February 1, 19 7 8) : Sections JJ-JJ' through LL-LL' (Plates ZIIG and IIIH respectively) have been drawn through the ancient landslide in the vicinity of proposed Lots 84 and 87. Sufficient slide debris will be removed (both on and off tract) so as to permit keying and benching of the proposed fill into underlying bedrock. Some off -tract slide debris will be left in -place. The proposed remedial work will render the remaining debris more stable since most of the S. E. MedaII & Associates, Inc. Weatherfield Homes Page 6 May 5, 1978 W. O. 605D potential driving force will be removed* Conversely, if this debris were to be removed during development of the adjacent property, it would not affect the stability of the on -tract compacted fill.(Plates 3a-3f). The grading plan has been revised to show the approximate depths of slide removal. Item B 3 ( review item 9 , dated February '1', 1978): The County refers to a 10f degree dip that can be measured from the geologic section up dip from the cut-off for the buttress analysis made on the Section W-W1. The County Soils Review Sheet dated April 25, 1978, states in Item 1 that Section W-W' appears to meet County standards. The buttress shown on this cross section has been adequately designed to support daylighted bedding. This is further justified by Plates 4a-4f where an additional 40 feet has been added to the driving force. The original cut-off was selected in accordance with County standards. Item B4 (Geologic item 10, dated February 1, 1978) See Items Al and A2 above. Item C. All reponses -to Soils Section Review Sheet, dated April 25, 1978, are included in Item D5 below. See Plate 6, attached, for stability calculation. S. E. Medal; & Associates, Inc. Weatherfield Homes May 5, 1978 Page 7 W. O. 605D Item D1(i, ii, iii). Subdrains will be placed in shear keys (see Item 3, Soils Section, below)and they have been shown on the grading plan. In any event, a) all stability/strength calculations are based on strength parameters for essentially saturated soil; and (b) accumulations of "dammed" water would be very unlikely due to the strong bedding and joint patterns, which would likely conduct water downhill under any compacted fills (such as keys). The installation of these drains was not considered necessary as we have previously discussed. In our opinion, adequate surface control will preclude the effectiveness of the recommended drains. Item D2. We have revised the geologic maps and the associated geologic sections. We have also reviewed the revised grading plans and they correctly reflect our conclusions and recommendations presented herein.and previously. Stability analysis of .revised slope conditions are included as Plates la-lf, 2a-2f and 5a--5f and the recommended remedial measures are shown on the grading plans. Item D3. All soils and geologic recommendations have been incorporated in the plans and each of the plan sheets has been signed manually S. E. Medall & Associates, Inc. Weatherfield Homes May 5, 1978 Page 8 W. O. 605D by the Project Geologist and Soil Engineer. Item D4. Note 31 on Sheet 1, grading plan, dated May 5, 1978, has been changed to read bi-monthly reports. Item D5 (responses to Soil Section Review Sheet, dated April 25, 1978). Item 1 on Soils Section Sheet). Section M--M' has been (a) lengthened to Section M-M'--M" and (b) revised to show the buttress inside the property line. A new buttress has been designed (100 ft.-long base). Design parameters, including sliding block cut-off plane, are attached hereto (Plates 2a-2f). Plate 4a--4f shows the revised calculation for Section W-W'. Item 2, 'Soils Section) . The basis for buttress design is the vertical plane of the associated geologic section, the most critical section. Therefore, the buttress width shown on grading plans will agree with design width only along the geologic section line. The original calculation sheets reference 1 above) show the true buttress widths perpendicular to slope (see noted on the calculation sheets). S. E. Medal] & Associates, Inc. Weatherfield Homes May 5, 1978 Page 9 W. O. 505D Item .3... Soil's Section) . A subdrain will be placed along the alignment, and in the bottom, of the shear key (on grading plans) . The filter will be the same design as that which has already been approved for the buttress drains. Respectfully submitted, S. E. MEDALL & ASSOCIATES, INC. JOHN T. GAFFEY, II R.C.E. 11494 JTG:JDT:ls JACK D. THOMPSON C.E.G. 582 Enclosures: Geologic Maps, Plate I Geologic Cross -sections Buttress Design Calculations, Plates l through 5 c: (4) Addressee 2) County of Los Angeles, Attention: Mr. Dave Popplar S. E. Medan & Associates, Inc. J k u d a Z ti) : 1 M I N rr v v r I n n^ ti pm3 Q d y n A nnw Ll o 0acr dam} z VyJN D c Ty_q W W Ul 4 a n pi -A i L I n W.O. 60 5 D DATE ` 7 BUTTRESS BY BASE WIDTH CALCULATION CROSS SECTION Y-M 1- M „ - UNIT WEIGHT BUTTRESS HEIGHT: 20 FT BEDROCK o[7v KCF SLOPE RATIO —':I (Hor. to Ver.) COMP FILL; KCF BASE WIDTH - LL FT. KEY DEPTH-. 3 FT. SHEAR STRENGTH ALONG BEDDING CAB= 0•-200 KSF ; 0AB = ra DEG. ACROSS COMPACTED FILL: CCF = a-ys2 KSF ; OCF= 26 DEG. FT. FN. SLICE AREAdA WEIGHT/W ANGL.E/1C. W- SI N W • COS— LENGTH/L NO. FT KIPS/FT DEGREES K/FT K/FT FT A 83 "D F"S ---[82,Q, S2 B v RESISTING FORCES : FR = LC + FN TAB! 0 ALONG BEDDING : FRA= LA CAR- FNATAN0A$= 25 D K/FT F €rA = F COS a = ELL K/FT RA COMPACTED FILL: FR$= LRCCF + FNR TAN CF= ? 2 K/FT NORMAL COMPONENT OF NET DRIVING FORCE (y 0) ; FRM = (FTA- FRA) SIN RATAN Ocj = K/FT M FORCES RESISTING:2 FIR = FRS + FRB+FR,y=---K/FT COMPONENT OF DRIVING FORCE ACTING ON ASSUMED FAILURE SURFACE FTA' = FTA COS 04A= -58 K/FT FACTOR OF SAFETY F.S. _ FR = 6 3>/,so FTA1 D PLATE S. E. Madall a Assocl-al$it Inc. Consultants in tha Earth Sciences 3070 Sq 1-1y 17 r., Lm An. a a7es, Ca. 9OOFR, (2131 39a40]9 2166 S. iia[ha y 5l.. San Ara, Ca. 9'.7.75, 57141 54y-6e02 BUTTRESS BASE WIDTH CALCULATION PSEUDOSTATIC CASE = K = Oz ( CROSS SECTION \/4`A'-r,4 DRIVING FORCES FTAS = FTA+ KFNA= ILL K/FT FTAS' = FTAS COS °( A= FTDS= FTB +KFNB= 2F= FTAs+FTBs= RESISTING FORCES FRAS = LA CAB + (FHA-KFTA) TAN OAB= K/ FT FRASI = FRAS COS Or' A = FRas = LB CCF + ( Fria-K FTs) TAN OcF = FRB FRNS =(FTAS-FRAS)SIN-CA TAN Q)cF- FR = FRAS t FRBs- FENS - r FACTOR OF SAFETY: F. S. = FT W.0. '40 DATL -a- L ; 2 1 Y - ig'2 K/FT K/FT K/FT K/FT K/FT f K FT K/FT PLATE /c- S. E. Medal) A Associalai, Inc. Consultants in the. Earth Sciences 3030 So. R.—ty O•., Los AngMas, Ca. D0055, (213) ,190-4079 i 2168 So. Macho. V Sr„ Santa Ana, C,, 92705, (114) 546-6n02 w 8 u n c sma m 1A n W 40 Q I ? m G S N v= claz NtlI W- w• 1 1iAA Q O h• rnJ J1 cn ALATC 1 c- BUTTRESS KEY DEPTH CALCULATION CROSS SECTION LA--LL-rA-" DATE v BY UNIT WEIGHT BUTTRESS HEIGHT: `a . FT BEDROCK: 01122 KCF SLOPE RATIO= 2 =1 (Hor. to Ver.) COMP. FILL-,-Y,:-2" KCF BASE WIDTH: (a FT. KEY DEPTH: FT. SHEAR STRENGTH ALONG BEDDING CAB=Q•ZUv KSF ; OAB= 10 DEG ACROSS-BEDDROCK— C= o -LO KSF = 2& DEG SILL ''== ` = - FT FN SLICE AREA/A WEIGHT/w ANGLE/cc w•SIN- W-COS- LENGTH/L NO FT KIPS/FT DErjREES K/FT K/FT FT Al 9 t D 0 7. 2 4L 7,6 168.? S B` 1-72,0 fie' l,v H/1 8 A'+B"2 3 F RESISTING FORCES: FR = LC t FN TAN O ALONG BEDDING : FRA=LA CAB+FNATANOAB= 32` K/FT FRS = FRACOS '-A-B= 26,7 K/FT ACROSS BEDROCK : Fi7-L$CBaf FNB TAN OaR= -7• 66 K/ FT NORMAL COMPONENT OF NET DRIVING FORCE (0); FR,,4 = (FTA—FRA) SIN c<AtBTAIN 03R= K/FT 2 FORCES R ESISTiNG; :2 FR = F-rB` + FRA'+FRB . FRR= `f, . K/FT COMPONENT OF DRIVING FORCE ACTING ON ASSUMED FAILURE SURFACE: FTA' = FTA COS O'A1 8= K/FT FACTOR OF SAFETY: F.S. = :*FR xs0 FTa--------- PLATE )c S. E. meal -all A Associate-s, Inc. Consultants in the Earth Sciences 383D So. El.++dy 9,., Los Anq.l—, C.. 90036. 12171 79"079 2168 S- N.[h,,-- Sr., Sant. Ana, Ca- 42705. 17M 5-&6-65a3 BUTTRESS KEY DEPTH CALCULATION PSEUDOSTATI C CASE = K= 6 f S CROSS SECTION M-M'-M" DRIVING FORCES FTAS = FTA+ K FNA= 22-1 K/FT FTAS ' = FTAS COS at A+R " RESISTING FORCES FTBS ` FTa - K FNa= FRAS = LA CAB FNA-KFTA)TAN 32,0 K/ FT FRASI = FRAS COS C( A*a= FRss = LsCaR4 (Fjja+KFTa)TAN 0sft= FRp4s=tFTcs-' FRA-)S1NcCA}aTAN 0$R= FFt' = FTD0 FRAS} Foss+FRNS= FACTOR OF SAFETY: F. S. = FTAs 4V.O. a5 DATE DY 1q' K/FT 0, 7 K/FT z4r5 K/FT 7, 7 K/FT K/FT K/FT 26 X/,o C)rfi , PLATE S. E. Medall aA s l , iris. Consultants in the Earth Scianoas O10 So. 6u nAY Ur., l.aa Anq.,.., C:.. 9G0 5, 12131 39Q4079 21613 So. Frarh,,way $ an ra A— Ca. S127 1S, 17141 545-rl;02 1 n ee V Y nayamQ P V 0U non 0 co fei .1-, Ufj a N cb mx¢ ILU w- co chi N r f r IN BUTTRESS KEY DEPTH CALCULATION CROSS SECTION -,k4" UNIT WEIGHT BEDROCK: o.c?o KCF COMP FILL: a -10 KCF W.O. — 0 -7 DATE 4- 21%7rJ, _ BY C'k— BUTTRESS HEIGHT - FT SLOPE RATIO. 1!7- :I (Hor. to Ver.) BASE WIDTH -- 100 FT. KEY DEPTH -- 7 FT. SHEAR STRENGTH ALONG BEDDING CAB= 1110 KSF ; CAB= /0 DEG ACROSS BEDDROCK CSR = /000 KSF ; OBR= -30 DEG SLICE AREA%A WEIGHT/W ANGLE/cc W• FT N SN« W-COS- LENGTH/LNOFTKIPS/FT DEGREES K/FT K/FT FT A! U67 j I dq-, D 1(e Z 1 62.3 2j 2 B' 76 C A!+ 6, y Zf f ° RESISTING FORCES : FR = LC t Ftj TAB) 0 ALONG BEDDING - FRA- LA CAB+ FNATAN OAB= ,3 K/FT FRA' = FFIaCOS '-"A,B= ACROSS BEDROCK: FRgzL3Csjj+Fria TAN 0a;i= NORMAL COMPONENT OF NET DRIVING FORCE OtO); FRN ' (FTA—FF?A) SIN ocAtSTAN 03R= ZEFORCES RESISTING;2FR=FTS'+FRA+FRO -rFRN= COMPONENT OF DRIVING FORCE ACTING ON ASSUMED FAILURE SURFACE FTA' = FTA C 0 S '<A+D" FACTOR OF SAFETY: F.S. = MFR FTA PLATE L L LS 6, 7 K/FT Ll K/FT K/FT 3D 6,3 K/FT 170,5 K/FT 30 >/, 5a Consultants in the -Earth Science. 3030 So. Fl—dY D,.. L— Anaelm, 1: Uf,066, (2131 ?J0.1079 2168 So. N.11n;,—y St-, .an1a An-,, Ca. J2704 t714) 546-5o02 tiV.0. - DATE BUTTRESS BY G L- KEY DEPTH CALCULATION PSEUDOSTATIC CASE = K= a-kL CROSS SECTION . M-m_'-t, DRIVING FORCES FBAs = FTA¢ KFNA= OO• E K/FT FTAS'= FTAsCOS C>tA;B=.-302,LK/FT RESISTING FORCES FIBS = FTS - K FNa= 27. K/FT FRAS = LA CAB + FHA— K F3A ) TAN OA 2 1 K/ FTB FRAS = FRASCOS CC A+B= ( R 2' 2 K/FT Faas = LB CBB11{ F?jB+KFTB)TAN 0aFt= PS, K/FT Fr?Ns =(FTA,,r Fi3A0S1Nc<A+aTAN 0SR= 0• K/FT 2 Fn` = FTBS+ FRAS+FRas+FRNS= 355, .K/FT FACTOR OF S-AF'ETY : F. S. = nFRS _ , /9 X /D G K. FTA s PLATES S. E. Medall 'A Asscci :alai, Inc. Consultants in tha, Earth Sciances 301S Sa. L1,110Y Dr., L,— A gu=+a, Ca. Sf n, 1't 17} 3961 1]9 216U :: a. LA Lh—sl S[...i-- n i, (:a.:)1103 , 1711} 546-6602 V l v v s J i 11 }//1-g- N J C J J d n r v c n hn r p pn VE ca OOp p4 w:s U JI. a O c W Mono to In N W 9,0 udui nwr 11 V' f L-A-ri- t BUTTRESS BASE WIDTH CALCULATION CROSS SECTION `LL4 `-1" w o. DATE BY G UNIT WEIGHT BUTTRESS HEIGHT: FT BEDROCK : 0, 120 KCF SLOPE RATIO : ILA : I (Hor. to Ver.) COMP. FILL: 0,f2.2 KCF BASE WIDTH : '00 FT. KEY DEPTH : 7 FT. SHEAR STRENGTH ALONG BEDDING CAB= 0,300 KSF ; OAB = 10 DEG. ACROSS COMPACTED FILL: C CF KS CF = 16 DEG• FT. FN. SLICE AREAfA WEIGHT/W ANGLE/pC W•SIN-- W•COS-c LENGTH/L NO. FT KIPS/FT DEGREES K/FT K/FT FT A, f l o V3, 765. ] f 3 13 RESISTING FORCES: FR w LC - FR TALI ALONG BEDDING :RA= a AI3 rta AB F !. C +F TANO 6 K/FT FR; = FRACOS r-CA = (S K/FT COMPACTED FILL: FRR=LaCCF+FNBTAN OCF= Zan. i K/FT NORMAL COMPONENT OF NET DRIVING FORCE (2 0); FR;N = ( F=A- FRA) SIN "<ATANOCF= K/FT FORCES RESISTING; FR = FRA' + FRg+FIRM 3 K/FT COMPONENT OF DRIVING FORCE ACTING CAN ASSUMED FAILURE SURFACE: FTC,' = FTC, COS "CA= 146, f K /FT FACTOR OF SAFETY : F.S. _ FA, = 2,b/'-5 a <, PLATE 2S' l S, E. Medan Si Associale, 3nC, Consultants in th3 Earth Sciancas 3030 So. Bundy Dr.,Loa Fng ae, Ca. F,0066, (2 124 39o-=079 2168 Su. H-h—"' Se., S.— Ana, Ca. 92705, 1714) 546-n502 BUTTRESS DATE- ='' BASE WIDTH CALCULATION I Y L PSEUDOSTATIC CASE_ : K= L-5 CROSS SECTION —m'— " DRIVING FORCES FTAs = FTA+ KFUA= 262 7 K/FT FTAS' ' FTAS COS C A= 25, K/FT FIBS FTR +KFNs= K/FT MiFT = FTAS'+ FTBS= K/FT RESISTING FORCES FRAS = LA CAB +(FAA--K FTA) TAN 0Ag= 1577 K/ FT FRAS' = FRASCOS 04 A= 1 ` S K/FT FRas = L®CcF + (FNS—K FTs) TAN 0CF = FR;3 = K/FT FRNS = (FTAS—FRAS) S I N c<A TAN O CF K FT E FR ' = FRAS t FR83+FRNs ` 9F KIFT FACTOR OF SAFETY: F. S. = F PLATE 12,2 Mada)1 8AA330c,ala3, Inc. Consultants in the Earth Sciences 3030 Sn. F—dy L]r_, L.os Anynt as, Ca, ranOAK. jZ131 Js1 4079 7168 So. Har''.away $r., Sanra Ana, Ca. 927, ns, 17 T41 54&r"2 I 1 r N QO y, V o m m J V N N NOSamp one H maw fA -C 'u? a2U_' Uj aCYfiw— a U W Q_ TKO` iedW lWo,M p mm AJ 1 I W.O. os DATE BUTTRESS BY L KEY DEPTH CALCULATION CROSS SECTION J;; _J_J- I UNIT WEIGHT BUTTRESS HEIGHT: 62 ___ FT BEDROCK 12 KCF SLOPE RATIO= 1,5 .1 (Hor. to Ved COMP FILL= , ;'- D KCF BASE WIDTH- FT KEY DEPTH: FT. SHEAR STRENGTH ALONG BEDDING CaB= °-° KSF ; t A$= /0 DEG ACROSS BEDDROCK CBR .oaa KSF ; 013R= 30 DEG FT . FN SLICE AREA A WEIGHT/W ANGLE/oc W - SIN- W • COS— LENGTH/LNOFTKIPS/FT DEGREES K/FT K/FT FT A' 4-7,1 9l3, 5 2-00 ac A'+ B' RESISTING FORCES = FR = LC + FjjTAN 0 ALONG BEDDING = FBA= LA CAB+ FNA TAN 0A3= 201. 1 K/ FT FRA' = FRACOS '-A,$= i 6.6 K/FT ACROSS BEDROCK - FgB=LBCB;t+FNB TAN OBB= 1'' K/ FT NORIVAL COMPONENT OF NET DRIVING FORCE (2:0); FRN = ( FTA—FRA) SIB] aA+BTANOaR= K/FT M FORCES RESISTING; FB = FTa' +FR +FjjI3+FRN= K/FT COMPONENT OF DRIVING FORCE ACTING ON ASSUMED FAILURE SURFACE: FTA' = Fri, COS ocA+B= 4-y, 2 K/ FT FACTOR OF SAFETY: F.S. - FB - F•5 FTC PLATE' S. E. AwAgdall o i iB , Inc, Consultants in the Eartn Sciences 3010 So. F3 npy 7 r„ Lnt An.a., C-.. 9o06 s, f2131 39EF40'19 216A So. N3rh—y Sr_. S—, AP e, Ca. 92703, 1714) 546-F602 BUTTRESS KEY DEPTH CALCULATION PSEUDOSTATIC CASE . K= o.-; CROSS SECTION S-1, ' DRIVING FORCES FTAs = FTA+ K FAA= W0, K/FT FTAS'" FTASCOS «A-*B= RESISTING FORCES FTBS = FTS -- K Fri$ _ FRAS = LA CA® t ( FAA-- K FTA) TA N oAB= K/ FT FRASI FRASCOS °( AW FRsS = LBCB.R4 (FNg+ K FTa) TAN 0e;R= FRNS=(FTAs- FRAS)SSN-CA4.9TAN Ogft 2 FRS = FTas } FRASS FRas+FF?Ns= FACTOR OF S"'AFE T Y • F. S. = FTAS W.O. o s- DATE 5 -2a BY c K/FT K/FT j67, , K/FT K/FT K/FT f S 2- L K/FT PLATE c_ Consultants in thq Earttr screnc3s ss>:.».:114sae aevz GQADE- 3o x 3 Fri kU.Y I 30' l I EX/ST/NG Ko UN -D f `` 2--- r 3 r5 GUT OFF i C7 y 07 o l ASSUMU 1 D Poll a N S. E. Modal] & Associates, Im7.. l u 14.r` ftrt s Consultants in the Earth Sciences 3030 5a. Bundy Dr., Los A.a.la% Ca. 90068, 12131 390-4079 - 2168 So. H.thaway St., Sent. Ana, Ca. 92705, (714} 646-6602 17231 E. Railroad 51., Clty of Industry, Ca. 9174B, (213) 964-2313 DATE _BY i SCALE . _ W.O. _ zsr--M oN TT --`TZ W-01 60 D z —7 s r O i= yy000 r X` 11 of V 11 U v 41 U fl it fl U nNe ovan1ON i UV40 Q aN- u 1 r 6 T9Ai >me rJ} 9 c:= C I W 6 u ui 4 N W U s. CO PI -A r_ ocF' 0,12o j-cr- Copllp 5HEAIR i/a ac VJr- V F,U-r-`rrc7 s SLbPc P-A-no r CrGp, `p Fasu WIDTH: I o0 LYT b o:so oACP-.o>> CoMp FILL = CIF F-sL c PT u4rN,L WJ , I- s >( VV oQC - F• 2- KI FY K/ F-` FT 4 r 69.g l I aI 0. tea t •. --- - fla v aedkn _ Fpz= L4Ctt- F-,, Ton K/CT E a Le Cfiu i NG'. TOA CPA )1,7 VFr k e, F ems f c:r'7,- •r ar-nl on. o n j ;.r iYci r<<Tr bocce o t_2" }off i Fvu) F 2 _ FTA - 4/ AFn_A S no; r - j n A may- J'{trnal f;., f1Crf n B(01 Gin NCI` )no,r Uo cc 1 i CDS Fi I 2 K!P FOP 7-7 kz-, oZ ;;,1 r 7ICAD, iT vj i F—iss FT-c- il C. 2- r-Os c)A C kAl T5jo7, F F-R-c is) 2 cit GAS r_7n Fla n F P, FT Fik s + CF[,,,7,7 FZ- A T' -d c t Cl OD w IS q RI n aa v " C nmm 646 N SwaQ_ c ooU qW ti J N r O to Neo ti mia Q LU h w' in t W f'L A T-i — . 4 o T TE E= 1-(fke Y51s I OUT-r-S5 k_`_! "DFP'iH CAGY A-TroNI : DA : 5 2--78 Goss secrfa N w -w ` P-Y No C L IJNIT laatr':g-r 12LMK--55 Hr--16 HT RGDp")cK = 0 ° 12o Kcv- SLOPS RATi o : 2- 1 C N p v.) WIDTH: 00 K Y —V e r 0 o0F. R f cRasS B K CAR J- aoo SLICE gyp, We-ic4T hNCiL 1p( wsTh WGasp NGTH L iFrF k/ E< . k/ 202:() 2 2. I 37 AcrJc . D TLoK fv 32 R- 51sTl N Fz 0.Vzc.,.S 4 G alU ` add, ; BRA = LA C',,+ G Tar. c K/FT A' = Fri Cos CAA+C a W, o' ccas5dr ct , Fp" J)AB TR FFzA Sin co o.11Pcl3 fC O Cnft iS7rtfJ6 sC rl ott, p1G[ rYl 1`Psi ( ,t ncj t arcDI, lo&ln G FP- A- Fk-a' KC - r F i + P.N C 1 F i S 2 7. Q- GOb[ PO1•l e•iT D --Ppl\IfNC 5VCE.S fit-TLtG ON A,S50MeI P_ FAILURE 5c1CZ F- fA = FA C65 C>A+c T Ft B0 F f c Fu; T-E rX — ! cFzass rION w-w V v 1 r Y <S L t C o k No VAT F, FrAs' - FTAs Frss = TT,6 4 k i=Ne FT65! - re5 Cas gfc TGS FTc — k Fnr c C FAsLACASFTCTaFRAS CoS Fps = LB cA6 AS K/ FT i FRSS FP 5 C OS g 1-C = eiz 1 — ' S' TH Rhs A CoSoCJ3 6+C FZCS NS Ft, r 3 32,'L FT 3, rr L 2 I .2 r 9/ 10 FT l PLC- Z/ rr N mD o m G G v R n N Lry` Cl hV tlOd J' to VO t9 r r cr— Qce W m'a y r_ a ri du l arm f.. fA U Nn ill uj CO w JI r— t/ O tY U 1! 111 i! 11 BUTTRESS BASE WITH CALCULATION CROSS SECTION II UNIT WEIGHT BEDROCK = a, (2-0 KCF COMP. FILL-,y, r7!' KCF SHEAR STRENGTH W. O. G o DATE z 7S BY - BUTTRESS HEIGHT: W FT SLOPE RATIO: I1 1z : I (Hor. to Ver.) BASE WIDTH : 15 FT. KEY DEPTH:-3 FT. ALONG BEDDING CAB= a,zvKSF ; 0Ae = f DEG. ACROSS COMPACTED FILL: C CF ; 0,7s0 KSF OCF = 26 DEG. FT: FN. SLICE AREA A WEIGHT/W ANGLE/- Gil• SI Noc W • COSH L£NGTH/L N0, FT KIPS/FT DEGREES K/FT K/FT FT A B 75 9.0 09 RESISTING FORCES: FR = LC + Ft, TAN 0 ALONG BEDDING - FRA= I --A CAB+ FNATAN0A3= 2 9 K/FT FRA = FRACOS " LA = 2.? ' S K/FT COMPACTED FILL: FRa= Lr3CCF + Fp,B TAN OCF= 5,6 .K/ FT NORMAL COMPONENT OF NET DRIVING FORCE 0) ; FRN = (FTA- FRA) SIN C<ATAN CF= f K/FT n FORCES RESISTING; FR = FIR + FRa FRN= 38 f _. 4C/FT COMPONENT OF DRIVING FORCE ACTING ON ASSUMED FAILURE SURFACE: FTA' = FTA COS CCA= f 2- K /FT FACTOR OF SAFETY: F.S. = 'FR FTA, _ • 9 l a PLATE - • S. . P, lpdaU 3-t Associate , Inc. Consultants in the Earth ,iciancf.,,s 1010 S. 6 -,Jy Dr., Lo. Anyales, C.. 3,io6r. 1213) 790-4079 21bA 5u. Halh.—y Sl.. Sin ca A—, C, 92705. OTT 548-6607 W.O. BUTTRESS DATA BASE WIDTH CALCULATION 1 Y PSEUDOSTATIC CASE : K=°S CROSS SECTION -M-M DRIVING FORCES FTAS = FTA+ KFNA- 2L K/FT FTAS' = FTAS COS a A= L 2 K/ FT FT®S _ FT13 } KFrqH= 1, LL K/FT FY= FTAs+FTE3S= 1;-7' 7 K/FT RESISTING FORCES FRAs = LA CAR +(FNA--KFTA)TAN 0Ae- 22f5 K/ FT FRAs = FRASCC)S C54 A= K/FT FftBS = LH CcF - (Ftja—KFTB) TAN OCF = FRB 15, G K/FT FRN, = (FTAS-FRAS) SIN 1" A TAN 0 CF= K FT FF?' = FRAS r FFSs+FRNS = LL '' K/FT r FACTOR OF SAFETY: F. S. = F = /•'0 6; T PLATE S. E. ",lead & d sso(,- 93, Inc. Consultants in the Earth Sclances 2558 So. H,th,-y SL.. Sams Ana, Ca. 9'2109, 17I4S 5do-5602 n n n O b P O V naY ADoxA3/ qp} J ca O nmrr h aWJ Cl CO J . t In . wO ' 11 0 BUTTRESS KEY DEPTH CALCULATION CROSS SECTION M -- Y'L,' W.O. 6Q DATE 5- 2 -23 BYc _- . _ .. UNIT WEIGHT BUTTRESS HEIGHT. Zq- FT BEDROCK: r, 12.0 KCF SLOPE RAT 10- i/L: 1 (Hor. to Ved COMP FILL: KCF BASE WIDTH: I2 FT. KEY DEPTH =_ FT. SHEAR STRENGTH ALONG BEDDING CAB= O'D-00 KSF ; OAB (' DEG ACROSS BEDDROCK CRR = LLO KSF ; OEM= 211 DEG FT FN SLICE AREA A WEIGHT/W ANGLE/ot W-SIN- W - COS- LENGTH/L NO FT KIPS/FT DEGREES K/FT K/FT FT A' 20,2 119,6 55 D' 3,L- 30" 1,7 2,0 J I CA!+D, : Z(O0 RESISTING F011iCES : FR = LC l- Frj TAN 0 ALONG BEDDING = FRA= LA CAB+ FNATAN 0AB K/FT FRA' = FRACS CIcAy8 ACROSS BEDROCK: FRg-LBC$al F?re TAN 0aR= NORMAL COMPONENT OF NET DRIVING FORCE (2:0); FRN = (FTA-FRA) SIN ocA-kaTAN 0alt= 2 FORCES RESISTING; 2 FR = FTa' + FRA +FRS -e FRri= COMPONENT OF DRIVING FORCE ACTING ON ASSUMED FAILURE SURFACE FTA' = FTA COS °A+e FACTOR OF SAFE TY = F.S. ==--R, FTA K/FT K/ F T f K/FT 3 ' K/FT O K/FT PLATE Lac S. E. I'Aada31 & A3300at 3, Inc, Consultant; in the Earth Sciences 30]0 $o. P..nuy D,,, L 5 :.ng.laa, Cr- 9U0%:u, 2131 ;:96-10i9 2t66 Sn. }i atha y '; „Semi An,., Ca- 72705, {7141 5-10-6602 k, W.O. too 5 J DATE 5- C' - BUTTRESS BY KEY DEPTH CALCULATION PSEUDOSTATIC CASE . K = 0:15 CROSS SECTION LL- _'' DRIVING FORCES FTAs= FTA* KFMA= 38.7 K/FT ETAS ' = FTAs COS «Aas = 2''y K/FT RESISTING FORCES FT$s = FTS — K F;yB= L E, K/FT F RAS = LA CAB f (FhA7 K FTA) TA N Co= 31, K/ FT FRAS'= FRASCOSC(AfB= -K/FT FR13S = LBC3R4 (Frjs+KFTB)TAN 0aR= K/FT FRRS=(FTArFRAS)SINr-<A+RTAN0RR= 2.7 K/FT M F R I = FTIS54 FRAS+FRasI,FR sK/FT FACTOR OF SAFETY: F. S. = F TASPLATE 5 E. Nledaii Ass clali:)3, Inc. Consultants in the Earth Sciences 3( 33D So. flu yy []r„ 1_P• Anyd vq C.i, :i110;ti, ;Z 13 3v0-1079 2163 So, Ha1F way .[.. S... 1, A., C., J27u,:. 1114, 546 6602 tit Sim 11 N tin te ri 317Z zs 00 U Q