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Home My WebLink AboutCT 08-02; LA COSTA CANYON HOMES; ADDENDUM TO LIMITED SITE INVESTIGATION UPDATE; 2007-11-06'- ~-Pf"~-~~. ~ ~.s~ t'l~ -(;'t:Jf'7 EAST COUNTY son. CONSULft;;O~ -C'j bbt;b-7 AND ENGINEERING, INC. ~ 10925 HARTLEY ROAD, SUITE" RECEIVED SANTEE, CALIFORNIA 9 lt7) (619) 258-7901 "'~ JA~l ~ e .,"'1"!3 Fax 258-79 CO~ 11 i U f-J'<>' -:,.." L',.ll~CI OF CARLSBAD Mr. Steve Grady CO~ ~6)~~ PLAN"N'i'ffil~07 . The Focus Group, LLC ~~ Project No.Ol-1147Hl(IE) 7938 Ivanhoe Avenue, Suite ''B'' ')--II f1 7': 'I' • '\. "'-._ La Jolla. California 92037 <l.~" '-I ,,~If\;~ ~,n .If r) r' Subject: Addendum To Limited . , Itt,> Two Proposed 8-Unit Resl ential Buildings . 8-9,6 , ~ North Side of La Costa Avenue, West ofRo~eria Street I \ tJ -h t City of Carlsbad, California Ilc.{: tt f " References: See Attached Dear Mr. Grady: Uf ~t{tll \!J ' Ie .,,1 Jrn {t t/~(fI1 ~u~ -, <\V ~' Nutf· In accordance with your request, this addendum has been prepared to addr~p.m~d residential development at the subject site. We have reviewed the pre1j~ary si~e .. grading-p ... ~the referenced ~~ prepared by Ma3son & Associ~ ~ ~ ~ ~ 6,~:; It IS our understanding that the new proposed constmction will mclud~",umt-re$aeD.tial ~ buildings; both structures will be two-story over basement garages. As previously discussed, the major factors affecting the proposed development are the' stability of the adjacent 80-foot.high steep slope to the north, the expansion potential of the subgrade soils-and: settlemen~-of-poorly' compacted :fill soils. Based upon these geotechnical constraints, the cast-in-drilled-hole caisson and grade beam foundations recommended in the referenced soils report (Referep.ce No.5) are still valid for the proposed constmction. ~ are anticipated to be approximatly 15 feet below basement grade in the upF~and 20 feeTiilth~wer pad. Overexcavation and recompaction of floor slab areas tc;(a minimum depth of 3 fee:"recommended. The following additlonaI recommendations should~ incorporated in the ~!gn-·and construction. ~.....-.-"" Permanent Slopes Permanent cut and :fill slopes are anticipated to be less thail 15 feet in height and may-be constructed at a maximum slope ratio of 2: 1 (hor. to vert. (to the heights indicated on the plans. Slopes constructed in:such a manner are anticipated to be groSsly stable. Due to the granular nature of the on-site soil materials, surficial erosion is a common probleIitit.is.J'£Eo~ended t.!!!-drol:l t resistant vegetation be planted on these slopes as soon as practical to enhance their Stability. o. ;r THE FOCUS GROUP1 LLC PROJECTNO. Ol-1I47Hl(1EJ Temporary Slopes For the excavation of basement garages or utility trenches, temporary vertical cuts to a maximum of 4 feet may be constructed in fill or natural soil. Any temporary cuts beyond the above height constraints should be shored or further laid back following a 1:1 (hor. to vert. ) slope mtio. OSHA guidelines for trench excavation safety should be implemented during construction. Retaining Walls Cantilevered retaining walls should be designed for an "active" lateral earth pIessUre of38 psfIft (38 pcf EFP) for approved granular backfill and level backfill conditions. Where cantilevered walls support 2: 1 (hor:vert) sloping backfill, the equivalent active fluid pressure should be increased to 58 pcf. Cantilever walls subject to .nniform surcharge loads should be designed for an additional uniform lateral pressure equal to one-thiId (1/3) the anticipated smcbarge pressure. Restrained walls should be d~ utilizing an "aP-rest" earth pressure of 60 psfIft (60 pcf EFP) for approved granular and level backfill Restrained walls subject to uniform smcharge loads shoUld be designed for an additional uniform JateIal pressure equal to one-baJf (Ill) the anticipated surcharge. East County Soil Consultation and Engineering, Inc. appreciates the opportunity to continue our role as geotechnical consultant If we can be of :further 8$Sistance, please do not hesitate to contact our office. Respectfully Submitt~ Mamadou Saliou Diallo ReE 54071, OE 2704 MSDfmd Cc: Addressee (3) Dee Landers, Howes, Weiler & Associates (1) Dan Masson, Masson & Associates (1) 2 ..... ---------------------------------------- THE FOCUS GROUP. LLC PROJECT NO. OJ-J J47HJ (lE) REFERENCES I. "Limited Site Investigation Update, Proposed 26-Unit Residential Development, North Side of La Costa Avenue, West of Romeria S~t, City of Carlsbad, California", Project No. 01-1247GI(lD), Prepared By East County Soil Consultation and Engineering, Inc., Dated March 5, 2007. 2. "Drainage Swale Clarification, Proposed Apartment Complex, Units No.4 and 5, North Side of La Costa Avenue, West of Romeria Street, City of Carlsbad, California", Project No. 01-1247GI(l"C), Prepared By East County Soil Consultation and Engitieering, Inc., Dated February 17, 2004. 3. "Drainage Swale Assessment, Proposed S-Unit Apartment Building, Lot 409, North Side of La Costa Avenue, West of Romeria Street, City of Carlsbad, California", Project No. 01-1247Gl(lB), Prepared By East County Soil Consultation and Engineering, Inc., Dated December 8, 2003-. 4. ~'Addendum to Limited Site Investigation, Slope Stability Analysis and: Drainage Swale Location, Proposed 26-Unit Apartment Complex, 4 Vacant Lots, North Side of La Costa Avenue, West of Romeria Street, City of Carlsbad, California", Project No. 01- 1247Gl(lA), Prepared By East County Soil Consultation and Engineering, Inc., Dated May 20, 2003. 5. "Limited Site Investigation, Proposed 26-Unit Apartment Complex, 4 Vacant Lots, North Side of La Costa. Avenue, West of Romeria Street, City of Carlsbad, Califomia", Project No. 01-124701(1), Prepared By East County Soil Consultation and Engineering, Inc., Dated June 9, 2001. 3 ~as;/,#~~~ " ) ~ ~ i, • :0 • &/ C/I!!Y"~:& c4:h tf~/fd7 ~.:ruae9' ~'-.. --... "" EAST COUNTY SOIL CONSULTATION AND ENGINEERING, INC. 10925 HARTLEY ROAD, SmTE "I" SANTEE, CALIFORN.IA 92071 (619) 258-7901 Fax 258-7902 Legacy Development, LLC 6965 EI Camino Real, Suite Carlsbad, California 92009 105-451 Subject: Project No. 01-1147H1(1) Limited Site Investigation Proposed 26-Unit Apartment Complex 8C\[aci:t1;Lt __ ~LQIt:~GZJNorth Side of La Costa Avenue .West of Romeria Street City of Carlsbad, California. Ladies/ Gentlemen: ('tv~~ In accordance with your request" we have performed a limited investigation of the soil conditions a:t the subject site. The investigation was undertaken to provide the soil engineering criteria for site grading and to recommend an appropriate foundation system for the proposed apartment complex. Our investigation found .. :tha·t· --the-----r>r0];)0s.ed builc;lj.ng. pads are primarily underlain by undocumented fill SQ.il:;> to a maximum depth of appro.ximately 15 fee,t be-.10w·~-:ex±stitrg,"·~grade. Mudstone and sandstone of the 1 Santiago Formation were underlying the undocumented fill. The fill soils generally consist of s'oft to medium stiff sandy C'lay exhibiting a moderate expansion _potential and a moderate compressibility. ~ It is our opinion that the provided the recommendations construction. proP.9.'1,~d he+~:i,p. development is feasible are ,implemented during Respectfully submitted, ~&~f1\~1 Mamadou Saliou Diallo, P.E RCE 54071 LEGACY DEVELOPMENT, LLC PROJECT NO. 01-1147H1 (1) INTRODUCTION This is· to present the finding~COnClusions of a soils investigation for a proposed ~8-unit apartment complex to be located on the north side q.V'La Costa Avenue, west of Romeria Street, in the City of Carls6ad, California. The objectives of the investigation were to determine the existing soils conditions and provide recommendations for site development. In order to accomplish these obj ecti ves , Jive (5) exploratory borings were drilled to a maximum depth of ~1.0 feet; undisturbed and loose bag samples were obtained, and~atory. tests were performed. SITE DESCRIPTION AND PROPOSED CONSTRUCTION The subject site is located on the north side of La Costa Avenue; west of Romeria Street, in the City of Carlsbad, California. The site was previously graded into 4 relat'ively level building pads. Prior to the grading operation, the site sloped moderately to the north. Vegetation consists of gras~ The proposed ·development includes the construction of a ~~unit, two-story over garage apartment complex to be founde~n caisson fQoting$' with a $:~ta~:- _9n-gl;.~d.e,floor system. "",,.,.. .. , .... "'."'.""".< ... ,-~ FIELD INVESTIGATION Five exploratory borings were drilled with a gas-powered auger to a maximum depth of 31 feet on April 12, 2001 a·t the approximate locations shown on· the attached Plate No.1, entitled "Location of Exploratory Borings". A continuous log of the soils encol:lntered was recorded at the time of excavation and is shown on Plates No. 2 & 6 entitled "Summary Sheet". The soils were visually and texturally classified according to the filed identification procedures set forth on the attached Plate No. 7 entitled "Uniform Soil Classification Chart. 2 ) , LEGACY DEVELOPMENT, LLC PROJECT NO. Ol-1147Hl(l) SURFACE CONDITIONS The surface soils encountered during the course of our investigation were fill soils. consisting of tan sandy clay, moist to wet, ~ops.~. to medium dense to a maximum depth of fi.fteen (15) feet.-These soils were underlain by mudstone and sandstone of the Santiago Formation (Tsa). EXPANSIVE SOILS An expansion test was performed on representative samples of the fill soils encountered to determine volumetric change characteristics with change in moisture content. An Expansion index of 61 indicates a mo.der.ate potential for expansion. GROUNDWATER Groundwater was not encountexed during the course of our investigation. Groundwater is anticipated at a depth greater than 100 feet. We do not expect ground wate.r to affect the proposed development. GEOLOGIC HAZARDS A review of the available geological literature pertaining to the site indicates the existence of the Rose Canyon Fault Zone approximately 10.5 Km to.the west. Ground shaking from this fault or one of the major active faults in the region is the most likely happening to affect the site. With respect to this hazard, the site is comparable to others in the general area. The proposed· residential structures should be designed in accordance with seismic design requirements of the 1997 Uni£orm Building Code or the Structural Engineers Association of California using the following seismic design criteria: PARAMETER VALUE UBCREFERENCE Seismic Zone Factor, Z I 0.40 Table 16-I -------\ ~~~~~~-~~------+---------~---------~~~~~ Soil Profile Type Sn Table 16-1 ~S~e~i~snn~·c~C~o~e~ffi~1~ci~en~t~,~C~a ______ ~ ______ 0~.~44~ _____ -+~T~a~bl~e~1~6~-Q~ ________ ~~ Seismic Coefficient, Cv 0.64 Table 16-R -----------1 Near-Source Factor, Na 1.0 Table 16-S --------1 Near-Source Factor, Nv 1.0 Table 16-T Seismic Source B Table 16-U ---------1 ~-----------------~------------------~----- 3 LEGACY DEVELOPMENT, LLC PROJECTND. Ol-1147Hl(l) Based on the absence of shallow ground water, type and consistency of the underlying soils, it is our opinion that the potential for liquefaction is very low. CONCLUSIONS AND RECOMMENDATIONS The following conclusions and recommendations are based upon the analysis of the data and information obtained from our soil investigation. This includes visual inspection; field ,investigation; laboratory testing and our general ~nowledge of the soils native to the site. The site is suitable for the proposed development provided the recommendations set forth are implemented during construction. GRADING AND EARTHWORK ~,),(l;!I.~'4~~~""~~"~m<ll;w.!~~~~ S:1,t.e-~g"'raair;g should. begin wi th clea~ing a~"11±nqJ'r ...• ~~p ~ the ~emoval of vegetatl.on and deleterl.ous materl.als. It I~ro:~ ~" understanding that the four previously graded pads will be gradeo,-r.,._ into two level building pads. Therefore, we recommen that the ,,~, existing fill soils to a minimum depth of iv-(5) feet be ~ 'O..<!i,~rexcavated, moisture conditioned 2 to 4 perce ·~_,9l?J:;;iml:!lIt['>.~'· and~Ofi1f)'a~t,eg.\'ll';';",!;,q __ a m-tnimum of 9,0 J?","~J;,.9_~J:l,i,~"";.'\':Eerl"a·' ·-ve'~~cr~t.rs""fty. The "" :!?~~~~~~~~.~~~ ,'" compacted fill mat will provide support for he garage slabs, underground utilities, driveway and parking reas. Prior to the fill placement, the lower building pads sho9~d be overexcavated to a minimum depth of 'X feet, and recompacteli as recommended above. The actual depth ancl extent of removal stlfould be evaluated ~n the field at the time f excavation by a r~resentative of this firm. Grading should :one in accordance th the attached appendix A. IMPORTED SOILS If imported soils are required to achieve proposed grades, ,they should be non-expansive, i.e,;pn expansion index of 20 or less and approved by ~~:;:s. en~ prior t~::t~:eliverY. ~#S-II-~ 2~. S-/;t -3 \ r rt" " , LEGACY DEVELOPMENT, LLC PROJECT NO. Ol-1147Hl(l) CAISSON FOUNDATION Due to the presence of undocumented fi,ll soils to a maximum depth of X5 f'ee':t, a foundation system consisting of a combination of caissons and grade beams is recommended. The cast-in-drilled-hole (GIDH) concrete:, caissons are anticipated to be founded in the dense sandstone/ muds.tone: of the Santiago Formation. The allowable static axial load capacities for CIDH concrete caissons may be obtained using the following Terzaghi and Peck equation: Where: QuIt = ultimate load capacity in compression C = cohesion in psf R = caisson radius ' CA = adhesion in psf A 12-inch diameter cais·son rounded to a depth of 10 .. feet 'b~lQW< existing:, grade I1).ay J5e'ae-~ngnea-ror an' allowable load capacity of 10 kips using a sifety factor of 3. The desig~ incorporates both s~de aq~tion and ~e:p.~ :~ag? to provide total pile a:apacfry. It '-must . oe emphasrzed that ""the "friction plus end be~ring" condition can be considered on~y if the bottom pile borings are cleaned of all loose material prior to the placement of steel reinforcement and concrete. The load capacities of all caissons may be increased by one-third for short-term transient loadings, such as wind and seismic activities. Resistance to uplift may be obtained using an adhesion between shaft and the concrete caisson of 750 psf. No appreciable settlement is anticipated for caissons designed in accordance with the recommendations and founded in the Santiago Formation. I~ caisson spacing is at least three times the caisson diameter, no r~duction in'load capacity is considered necessary for a group effect. If structural design indicates that caisson spacing is critical, the group action can be evaluated after the total column l,oad and geometric constraints are determined. It should be noted, that the basic formula used is based on, load transfer to the supporting soil. Design considerations also should" be given to the caissons as structural members. 5 LEGACY DEVELOPMENT, LLC PROJECT NO. OI-1147HJ(J) The design of caissons to resist lateral loading at the ground level may be based on the curves shown on Plate No.8. If greater deflection can be tolerated, lateral loads can be extrapolated to isolated caissons spaced no· closer than 3 caisson diameters on center perpendicular to the line of thrust and 8 diameters on center parallel· to the line of thrust. The lateral resistance of caissons at ground level also depends significantly on the proper implementation of site preparation. CONSTRUCTION CONSIDERATIONS The proper installation of CIDH caissons will be of critical importance. Since caisson design includes end bearing, it will be necessary to clean all loose material from the bottorn of the borings. Caisson borings should be observed arid approved by a representative· of this firm .prior to the placement of reinforcement ALLOWABLE BEARING·CAPACITY FOR GRADE BEAMS For. the grade beams, an allowable soil bearing capacity of. 1500 pounds per square foot may be used when founded a minimum of 12 inches into the compacted fill. This value may be increased by 20 percent for each additional foot of width and/or depth to a maximum value of 3000 lb/ft2. CONCRETE SLABS Concrete floor slabs should be a nominal 4 inches thick. Reinforcement should consist of #3 bars placed at 18 inches on center each way. Slab reinforcement should be placed within the middle third of the slab by supporting the steel· on chairs or concrete blocks "dobies". The slab should be underlain by 2 inches of clean sand over a 10-mil visqueen moisture barrier. The effect of concrete shrinkage will result in cracks in virtually all concrete slabs. To reduce the extent of shrinkage, the concrete should be .placed at a maximum of 4-inch· slump. The minimum steel recommended is not intended to prevent shrinkage cracks. 6 " LEGACY DEVELOPMENT, LLC PROJECT NO. Ol-1147Hl(l) Where moisture sensitive floor coverings are anticipated over the slab, the 10-mil plastic moisture barrier should be underlain by a capillary break at least 4 inches thick, consisting of 3/4 inch crushed rock. SLOPE SETBACK Proposed structures and other improvements that are located within 8 feet of the f?ce of existing slope. could suffer differential movement as a result of the poor lateral stability of these soils. Therefore, cp.isson footings for the proposed residential development should be placed at least 8 feet hack from the: top of. these slopes. ALTERNATIVE TO cAISSON FOUNDATIONS GRADING AND EARTHWORK Site grading should begin with clearing and grubbing, ,e.g. the removal of vegetation and deleterious materials. The undocumented fill and mudstone layer should be overexcavated, moisture conditioned 2 to 4 percent over optimum and compacted to ,a minimum of 90, percent relative density. The maximum depth of ov:.erexcava'tion is anticipated to be approximately 15. The actual depth and extent of removal should be evaluated in the field at the time of excavation by a representative of this firm. Grading should be done in accordance with the attached appendix A. FOUNDATION AND SLAB a. Continuous footings and/or spread footings are suitable for use and shall extend a minimum of 24 inches for the two story residential family dwellings into the compacted fill soils. Continuous footings should be 15 inches wide and reinforced with four #5 steel bars; two bars placed near the top of the footings and the other two bars placed near the bottom of the footings. b. Concrete floor slabs should be a minimum 4 inches thick. Reinforcement should consist of #3 bars placed at 12 inches on center each way. Slab reinforcement should be placed within the middle third of the slab by supporting the steel on chairs or concrete blocks "dobies". The slab should be underlain by 2 inches of clean sand over a 10-mil visqueen moisture barrier and another 2 inches of clean sand or gravel not exceeding 3/4 inch in size with no more than 5 percent passing the #200 sieve. The effect of concrete shrinkage will result in cracks in virtually all concrete slabs. To reduce the 'extent of shrinkage, the concrete should be 7 LEGACY DEVELOPMENT, LLC PROJECT NO. OI-1147Hl(l) slabs. To reduce the extent of shrinkage, the concrete should be placed at a maximum of 4-inch slump. The minimum steel recommended is not intended to prevent shrinkage cracks. SOIL BEARING VALUE (COMPACTED FILL SOILS) An allowable soil bearing value of 1500 pounds per square foot may be used for the design of continuous foundations and spread footings founded a minimum of 12 inches into the compac:ted fill soils. This value may be increased by 300 psf for each additional foot of depth to-a maximum value of 3000 lb/ft2. LATERAL SOIL PRESSURE Lateral resistance ,to horizontal movement may be provided by the soil passive pressure and the friction of concrete to soil. An allowable passive pressure of 150 pounds per square foot per foot of depth may be used. A coefficient of friction of 0.25 is recommended. The soils passive pressure as well as the bearing va.lue may be increased by 1/3 for wind and seismic loading. SETTLEMENT Settlement of' compacted fill soils is normal and should be anticipated. Based on the consolidation test results, a total settlement up to O. 75 inches across the structural span and a corresponding differential settlement up to 0.50 inches need to be considered in the structural design. UTILITY TRENCH EXCAVATIONS Excavations for on-site utility trenches may be made vertically for shallow depths and must be either shored or sloped at IH: IV for depths greater than 4 feet. Utilities should, be bedded and backfilled with clean sand or approved granular soil to a depth of at least one foot over the pipe. This backfill shall be uniformly watered and compacted to a firm condition for pipe support. The remainder of the backfill shall be on-site soils or non-expansive imported soils, which shall be placed in thin lifts, moisture-conditioned and compacted to at least 90 % relative compaction. 8 LEGACY DEVELOPMENT, LLC PROJECT NO. Ol-1147Hl(lJ -~ .... ~~~~~~~~~~.-DRAINAGE __ ,,,,,,,,," __ ,M '-__ ~.f>~""""~ Adeq~a4;.~~~~sures shall be undertake,n to properly ~'fi~Fl.,i'8,Q grade the ~if~" after the structures and other improvements are'1rt'''''-''F>,J,a e" ~UCh that the drainage water within the site and adjacEn~,i: /,7 properties is directed away from the foundations, footings, flOO~' J slabs and the tops of slopes via surface swales, and subsurface drains towards the natural drainage for this area. Proper' surface and subsurface drainage will be required to minimize the potenti~ of water seeking the level of the bearing soils under ~ne foundations, footings and floor slabs, which may otherwise r~~lt in undermining and differential settlement of the struc~\1.~~ and 0-~er improvements. 'l-"f;~~~' " ~. , .. ~ I'!~r?fl'll' ' LIMITS '@~~STIGATION ~i~~ , .... -~i~~~~}),"'"!::""l'1~,'"'' The recommendations provided in this report pertain only to the si te investigated and based upon the assumption that the soil conditions do not deviate from those disclosed in the borings. If any variations or undesirable conditions are encountered during construction, or if the proposed construction will differ from that planned at the present time, East County Soil Consultation and Engineering, Inc. should be notified so that supplemental recommendations can be provided. ' Plates No. 1 through 8, Pages L-l through and L-4, References, Appendix A and Appendix C are parts of this report. Respectfully submitted, Mamadou Saliou Diallo RCE 54071 MSD/md 9 ~ EX~A-~Y ~/NG B-2 - -\7 /l::IP" OF :S:~ _:/-I!.. 7&E-OF 5~ EAST COUNTY SOIL CONSULT A nON & ENGINEERING, INC. 10925 HARTLEY RD .• SUITE I. SANTEE. CA 92071 . (619) 258-7901 Fax (619) 258-7902 e: /ff.> ~/ WAle ~ ;za;/ NO:t?/-//4?#I(/ ;:t:A/tE NO. / LEGACY DEVELOPMENT, LLC PROJECTNG. OJ-1147HJ(J) I R S BORING NO. 1 N E 0 M L I P 0 A S L EQUIPlVIENT: GAS-POWERED AUGER L I T 0 A S I J C C T V D L L SAMPLING METHOD: E U E E A R P S S C= CHUNK SAMPLE D E C T A S B= BULK SAMPLE, R 0 H M I Y C M p F U= UNDISTURBED DRIVE 0 p I L I D N A N E C E T C A N E T F T T S N 1 E Y I I T 0 E P 0 SOIL DESCRIPTION T N T E N Y % % 0 SC FILL (Qat) -TAN BROWN, MOIST, LOOSE TO MEDIUM DENSE, CLAYEY SANp I --B 100.1 21.5 88 2 - 3 -" " " " WET, MEDIUM DENSE 4 - 5 --6 -7 -~ 8 - 9 - 10 - 11 SC SANTIAGO FORMATION (Tsa) -BLUEISH GRAY, MOIST TO WET, CLAYEY SAND 12 100.3 23.6 88 - 13 --CL BROWN, MOIST, SOFT TO MEDIUM STIFF CLAY 13.0'-13.5'= 8 BLOWS (SP1) -U 13.5'-14.0'= 14BLOWS(SP1) 14 14.0'-14.5'=25 BLOWS(SP1) 14. 5'-15. 0'= 13 BLOWS (SP1) . - 15 15.0'-15.5'=13 BLOWS(SP1) 105.7 19.6 -SM TAN. MOIST, DENSE, FINE GRAINED SILTY SAND 15.5'-16.0'=41 BLOWS (SP1) 16 --103.7 19.3 -, 17 BOITOMOf BORING -18 PLATE NO. 2 I I DATE LOGGED: APRIL 12, 2001 LOGGED BY; M. DUNCAN 10 LEGACY DEVELOPMENT, LLC PROJECT NO. Ol-1147Hl(l) I R s BORING NO. 2 N E 0 M L I p 0 A S L EQUIPMENT: GAS-POWERED AUGER L I T 0 A S 1 I C C T V D L L SAMPLING METHOD: E U E E A R p S S C= CHUNK SAMPLE D E C T A S B= BULK SAMPLE, R 0 H M I Y C M p F U= UNDISTURBED DRIVE 0 p I L I D N A N E C E T C A N E T F T T S N I E Y I I T 0 E P 0 SOIL DESCRIPTION T N T E N Y % % 0 FILL (Qat) -TAN BROWN, MOIST TO WET, LOOSE TO MEDIUM DENSE, CLAYEY SAND I - 2 - 3 - 4 -5 - 6 - 7 - 8 - 9 " -10 - H -.. 12 -13 SM SANTIAGO FORMA nON (Tsa) ----LIGHT TAN, MOIST, DENSE, FINE GRAINED SILTY SAND 14 -B --IS -BOTTOM OF BORING 16 . - 17 - 18 PLATE NO. 3 l DATE LOGGED: APRlL 12,2001 LOGGED BY: M. DUNCAN 11 LEGACY DEVELOPMENT, LLC PROJECT NO. Ol-1147HJ(J) I R S BORING NO. 3 N E' 0 M L I P 0 A S L EQUIPMENT: GAS-POWERED AUGER L I T '0 A S I I C C T V D L L SAMPLING METHOD: E U E E A R P S S C= CHUNK SAMPLE D E C T A S B= BULK SAMPLE, R 0 H M I Y C M P F U= UNDISTURBED DRIVE 0 p I L I D N A N E C E T C A N E T F T T S N 1 E Y 1 I T 0 E P 0 SOIL DESCRIPTION T N T E N Y % % FILL (Qat) 0 SC TAN BROWN, MOIST, LOOSE TO MEDIUM DENSE, CLAYEY SAND ----4' 5 ------9.0'-9.5'= 8 E!LOWS (SP]) 10 -U 9.5'-10.0'= I3BLOWS(SP1) --10.0'-10. 5'=40 BLOWS (SP1) 107.0 20.1 94 --- 15 SANTIAGO FORMATION (Tsa) -CL DARK GRA YlSH BROWN, M01ST, MEDIUM STIFF CLAY - , -- 20 ---SC-TAN MOIST, MOIST, DENSE, CLAYEY SAND -SM 25 -SM TAN, MOIST, DENSE, FINE GRAINED SILTY SAND -BOTTOM OF BORING -- 30 PLATE NO. 4 ~I DATE LOGGED: APRIL 12,2001 LOGGED BY: M. DUNCAN 12 LEGACY DEVELOPMENT, LLC PROJECT NO. Ol-1147Hl(l) 1 R s BORING NO. 4 N E 0 M L 1 P 0 A S L EQUIPMENT: GAS-POWERED AUGER L I T 0 A S I I C C T V 0 L L SAMPLING METHOD: E U E E A R P S S C= CHUNK SAMPLE D E C T A S B= BULK SAMPLE, R 0 H M I Y C M P F U= UNDISTURBED DRIVE 0 p I L I 0 N A N E C E T C A N E T F T T S N 1 E Y I I T 0 E P 0 SOIL DESCRIPTION T N T E N Y % % FlLL(Qaf) 0 SC TAN BROWN, MOIST, LOOSE TO MEDIUM DENSE, CLAYEY SAND --- -5 ---SANTIAGO FORMATION (Tsa) -CL DARK GRAYISH BROWN, MOIST, MEDIUM STIFF CLAY 10 --BROWN, MOIST, MEDIUM STIFF SANDY CLAY -- 15 --'--- 20 --SC-TAN MOIST, MOIST, DENSE, CLAYEY SAND -SM - 25 -SM TAN MOIST, DENSE, FINE GRAINE SILTY SAND --- 30 BOITOM OF BORING --. -- 35 PLATE NO. 5 I DATE LOGGED: APRlL 12;2001 LOGGED BY~ M. DUNCAN 13 LEGACY DEVELOPMENT, LLC PROJECT NO. Ol-1147Hl(lJ I R S BORING NO. 5 N E 0 M L I P 0 A S L EQUIPMENT: GAS-POWERED AUGER L I T 0 A S I I C e T V D L L SAMPLING METHOD: E U E E A R P S S C= CHUNK SAMPLE D E C T A S B= BULK SA1vIPLE, R 0 H M I Y e M p F U= UNDISTURBED DRIVE 0 p I L I D N A N E C E T e A N E T F T T S N I E Y I I T 0 E P 0 SOIL DESCRIPTION T N T E N Y % % 0 se FILL (Qat) -TAN BROWN. MOIST TO WET, LOOSE TO MEDIUM DENSE, eLA YEY SAND . I -2 - 3 -4 -5 - 6 - 7 -8 - 9 - 10 - 11 - 12 CL SANTIAGO FORMATION (Tsa) -BLUEISH GRAY. MOIST, SOFT TO MEDIUM STIFF CLAY 13" '-, 'l'll SM TAN MOIST, DENSE, FINE GRAINED SILTY SAND -15 -. 16 - 17 17 0'-17. 5'=28 BLOWS (SP1) -175'-18. 0'=70 BLOWS (SP1) 18 BOTTOM OF BORING PLATE NO. 6 I DATe LOGGED: APRIL 12,2001 LOGGED BY: M .. DUNCAN 14 LEGACY DEVELOPMENT, LLC PROJECT NO. Ol-1l47Hl(l) LABORATORY TEST RESULTS PAGE L-l The maximum dry densities and optimum moisture contents of the fill materials as determined by ASTM D1557-91, Procedure A and B which uses 25 blows of a 10 pound slide hammer falling from a height of 18 inches on each of 5 equal layers in a 4 inch diameter 1/30 cubic foot compaction cylinder and Procedure C which uses 56 blows of a 10 pound slide. hammer falling from a height of 18 inches on each of 5 equal layers in a 6 inch diameter 1113.3 cubic foot compaction cylinder are presented as follows: . SOIL TYPEIPROCEDURE BORING NO.1 @ 1.0' TO 11.0' lIA,TAN BROWN SILTY CLAYEY SAND MAXIMUM DRY DENSITY LB/CU.FT. 114.0 OPTIMUM MOISTURE CONTENT % DRY WT. 14.8 An expansion test in conformance with UBC 18-2 was performed on representative samples of on- site soils to detenriine volumetric change characteristics with change in moisture content. The recorded expansion of the sample is presented as follows: INITIAL MOISTURE CONTENT% SATURATED MOISTURE CONTENT% BORING NO.2 @ 1.0' TO 3.5' 13.6 29.7 INITIAL DRY DENSITY LB.lCU.FT. 97.5 15 EXPANSION INDEX 61 LEGACY DEVELOPMENT, LLCPROJECTND. Ol-1147Hl(J) REFERENCES 1: "1997 Edition, Uniform Building Code, Volume 2, Structural Engineering and Design Provisions". 2. "Maps of Known Active Fault Near-Source Zones in California and Adjacent Portions of Nevada", Page 0-38, used with the 1997- Edition of the Uniform Building Code, Published by International Conference of Building Officials. 3. "Geologic Maps of the Northwestern Part of San Diego County, California. Plate No.2, Geologic Maps of the Encinitas and Rancho Santa Fe 7.5' Quadrangles", by Siang S. Tan and Michael P. Kennedy, 1996. 4: "Soil Mechanics in Engineering Practice, 3rd Edition", by K. Terzaghi, R. B. Peck and G. Mesri, Dated 1996 5: "Drilled Piers and Caissons II", New York, NY, American Society of Civil Engineers, 153 p., Baker, C.M., Jr., Dated 1985. 16 MAJOR DIVISIONS SYMBOL DESCRIPTION GW WELL GRADED GRAVELS OR ORA VEL· SAND, MIXTURES. UTILE OR NO FINES GRAVELS GP (MORETHANI'l POORLY GRADED GRA VELS OR GRA VEL·SAND OF COARSE MIXTURES. LmLE OR NO FINES FRACTION GM >NO.4SIEVE SILTY GRAVELS, GRA VEL·SAND·SILT MIXTURES SIZE) COARSE GC GRAINED SOILS CLAYEY GRAVELS, GRA VEL·SA."iD-CLA Y MIXTURES (MORE THAN Y: OF SOIL> SW NO. 200 SIEVE SIZE) WELL GRADED SANDS OR GRAVELLY SANDS, LmLE OR NO FINES SANDS SP (MORETHANI'l POORLY GRADED SANDS OR GRAVELLY SANDS. OF COARSE LmLE OR NO FINES FRACTION SlVI < NO. 4 SIEVE SILTY SANDS. SILT -SAND MIXTURES SIZE) SC CLAYEY SANDS, SANp·CLA Y MIXTURES ML INORGANIC SILTS AND VERY FINE SANDS, ROCK SILTS & FLOUR. SILTY OR CLAYEY FINE SANDS OR CLAYEY SILTS WITH SLIGHT PLASTICITY CLAYS CL INORGANIC CLAYS OF LOW TO MEDIUM LIQUID LIMIT PLASTICITY, GRA YELL Y CLAYs. SANDY eLA YS. <50 SILTY CLAYS, LEAN CLAYS FINE GRAINED OL SOILS ORGANIC SILTS AND ORGANIC SILTY CLAYS OF LOW PLASTICITY (MORE THAN Y: OF SOIL < MH NO. 200 SIEVE SIZE) INORGANIC SILTS, MICACEOUS OR DIATOMACEOUS SILTS & FINE SANDY OR SILTY SOILS. ELASTIC SILTS CLAYS CH LIQUID LIMIT INORGANIC CLAYS OF HIGH PLASTICITY, FAT >50 CLAYS OH ORGANIC CLAYS OF MEDIUM TO HIGH PLASnqrv. ORGANIC SILTY CLAYS. ORGANIC SILTS IDGHL Y ORGANIC SOILS Pt PEAT AND OTHER HIGHLY ORGANIC SOILS CLASSIFICATION CHART (UNIFIED.SOIL CLASSIFICATION SYSTEM) CLASSIFICATION RANGE OF GRAIN SIZES U.s. STANDARD . GRAIN SIZE IN SIEVE SIZE MILLIMETERS BOULDERS Above 12 Inches Above30S COBBLES 12 Inches To 3 Inches 305 To 762 GRAVEL 3 Inches to No.4 76.2 to 4.76 Coarse 3 Inches to * Inch 76.2 to 19.1 Fine * Inch to No.4 19.1 to 4.76 SAND No.4 to No. 200 4.76 to 0.074 Coarse No.4 to No. 10 4.76 to 2.00 Medium No. 10 to No. 40 2.00 to 0.420 Fine No. 40 to No. 200 0.420 to 0.074 SILT AND eLA Y Below No. 200 Below 0.074 GRAIN SIZE CHART EAST COUNTY SOIL CONSULTATION AND ENGINEERING, INC. 10925 HARTLEY ROAD, SUITE "I" SANTEE, CALIFORNIA 92071 u.s.C.S. SOIL CLASSIFICATION 70 10 10 o w ___ ... . f7 I V1 ~ 1/ I elf I % I 1/ IA I I V CI. l71 I I I V Y I I "H4tyH I I I I '1 I AI ~'1 "UOI. •• I o 10 20 JO 010 '" 60 70 ao 90 100 UOUIO uuor {lJ.l. :: PLASTICITY CHART LEGACY DEVELOPMENT, LLC PROJECT PROJECT NO. 01-1147Hl(1) JUNE 8., 2001 PLATE NO. 7 co . o z ~ E-I :r Pol ,-... ,.....j '-' .-I ::t: r-... ~ .-I ,.....j I .-I o . o Z E-I U ~ .., ga Pol U H ....:l .. E-I ~ o ~ ~. A tj c3 ~ H LATERAL RESISTANCE CAPACITY' OF SINGLE CAISSONS (X KIPS ) o 01 =-r;f~I"~ ~'r~~-1~;:~:~ r tt' t·) 1 ill I .1!J 1 ·111 I g.? ;,y L~ge(ld.: 5 1---, PL I, 10" I \\ \ ....... 1-...·----------- ......... t;: >< .15' t-::'{ ....... VI ::::.:: ~ 20 I-' __ ~- VI ..... <5 l1.. o ::x: 25 r-0.. w Cl 30 1 35 1---- 40 -:-'\ ' \ \ \-1 d-- "~ '" ·1 ~. I-~ \ ' \ FIGURE 3 ALLOWABLE LATERAL RESISTANCE OF SINGLE DRILLED CAISSONS LEGACY DEVELOPMENT, LLC PROJECT NO. 01-1147Hl(J) LABORATORY TEST RESULTS PAGE L-l The maximum dry densities and optimum moisture contents of the fill materials as determined bi ASTM DI557-91, Procedure A and B which uses 25 blows of a 10 pound slide hammer falling from a height of 18 inches on each of 5 equal layers in a 4 inch diameter 1/30 cubic foot compaction cylinder and Procedure C which uses 56 blows of a 10 pound slide hammer falling from a height of 18 inches on each of 5 equal layers in a 6 inch diameter 1/13.3 cubic foot compaction cylinder are presented as follows: SOIL TYPEIPROCEDURE BORING NO.1 @ 1.0' TO 11.0' VA TAN BROWN SILTY CLAYEY SAND MAXIMUM DRY DENSITY LB/CU. FT. 114.0 OPTIMUM MOISTURE CONTENT %DRYWT. 14.8 An expansion test in conformance with UBC 18-2 was performed on representative samples of on- site' soils to determine volumetric change characteristics with change in moisture content. The recorded expansion of the sample is presented as follows: INITIAL MOISTURE CONTENT% SATURATED MOISTURE CONTENT% BORING NO.2 @ 1.0' TO 3.5' 13.6 29.7 INITIAL DRY DENSITY LB.lCU. FT. 975 15 EXPANSION INDEX .61 ---1 ,', DIRECT SHEAR SUMMARY I 5000 I I I I I 4500 I I I 4000 r I I I 3500 I I ! rr 8! 3000 I .... ! I ; (/) i I I (/) ! I i I I i W ! ! ! I I r= 2500 T I I . ' --I I i V I (/) I I 0:: 1 I ! ~ 2000 I I ~ I I I Y V (/) I ,1500 1/ T I ! I I i I I / ! 1000 , t ! I I .\ i I I I 500 I I I I ! I I i I I I , ' 0 ! . I I 0 500 1000 1500 2000 2500 3000 3500 4000 4500 5000 I NORMAL STRESS [PSF] (2 13132" SAMPLE) I 2M {O.S45} 1L (1.093) 2L (2.185) ANGLE OF COHE$ION INTERNAL INTERCEPT SAMPLE DESCRIPTION FRICTION (PSF) H3 @ 9'-10 Undisturbed 22 0 1000 & SOUTHERN CALIFORNIA LEGACY DEVELOPMENT, LLC PROJECT . SOIL & TESTING, INC. BY: DBA/SO !OATE: 04-21';01 JOB NUMBER: 01-1147HI( i) 1 'PAt:!R T -2 DIRECT SHEAR SUMMARY 5000 i I ·1 I i I i I ! i I I 4500 I 1 I ! i i J I I I I i 4000 1 ! I· I I I ! I i i I ! i I i I I ! i l I , 3500 i i I i . ! 1 I I ..... I ! u. I ~ 3000 ..... I I en I en I I IU· I I ~ 2500 , i I I t I i en ! a: i I I I ~ 2000 i ! I i I V I i en i 1/ ! I 1 1500 i Y I I I I I 1 i I I ! I i i 1000 I I '/ , I i ! I ; I / ; 1 ! I I . ! I i : I , ! I . : I I i : I ! ·1 500 V ! I ~ I I , 1 I I I j I i ! 0 0 500 1000 1500 2000 2500 3000 3500 4000 4500 5000 NORMAL STRESS [PSF] (2 13132" SAMPLE) I I 2M (O.545) 1L (1.093) 2L (2.185) ANG,J,.E; OF COHESION INTERNAL ... '\ INTERCEPT SAMPLE DESCRIPTION FRICTION (PSF) 'c " H5@ 17' Undisturbed 36\0 . 300 & SOUTHERN CALIFORNIA :f.,EGACY DEVELOPMENT, LLC ~ROJECT SOIL & TESTING, INC. BY: DBA/SO IDATE: 04-27-01 JOB NUMBER: Ol-1147H((1) . I. PAGE T.-':l .. . . -.... C G> ~ G> C. -Z 0 i= « 0 ::::i 0 UJ Z 0 0 " 0 1 2 3 4 -I-r'--~ ... '-.......... "--WA "!"ER ADDED P'" I~t-"'-~ I ..... ./ -..... ~ 5 6 7 8 9 10r-------~--_1--_+--~+_~_++_------~----~~--+_4_4_~~ 0.5 1.0 5.0 10.0 LOAD (kip I sq. ft.) H3 @ 10'-15' LEGACY DEVELOPMENT~ LLC PROJECT SOUTHERN CALIFORNIA SOIL & TESTING, INC. BY: DBAlKMS DATE: 04/27101 JOB NUMBER: 01":'U47Hl(1 PAGE L":4 LEGACY DEVELOPMENT, LLC PROJECT NO. Ol-1147Hl(l) REFERENCES 1: "1997 Edition, Uniform Building Code, Volume 2, . Structural Engineering and Design Provisions". 2. "Maps of Known Active Fault Near-Source Zones in California and Adjacent Portions of Nevada", Page 0-38, used with the 1997 Edition of the Uniform Building Code, Published by International Conference of Building Officials. 3. "Geologic Maps of the Northwestern Part of San Diego County, California. Plate No.2, Geologic Maps of the Encinitas and Rancho Santa Fe 7.5' Quadrangles", by Siang S. Tan and Michael P. Kennedy, 1996. 4: "Soil Mechanics in Engineering Practice, 3rd Edition", by K. Terzaghi, R. B. Peck· and G. Mesri, Dated 1996 5: "Drilled Piers and Caissons IP', New York, NY, American Society of Civil Engineers, 153 p., Baker, C.M., Jr., Dated 1985. 16 ,> • EAST COUNTY SOIL CONSULTATION AND ENGINEERING, INC. 10925 HARTLEY ROAD, SUITE I SANTEE, CALIFORNIA 92071 (619) 258-7901 APPENDIX A RECOMMENDED EARTHWORK. SPECIFICATIONS 1. General Description The intent of these specifications IS to obtain uniformity and adequate strength in filled ground so that the proposed structures may be safely supported. The procedures include the clearing and preparation of the land to be filled, processing the fill soils, the spreading, and compaction of the filled areas to conform with the lines and grades as shown on the approved plans. The owner shall retain a Civil Engineer qualified in soil mechanics (herein referred to as engineer) to inspect and test earthwork in accordance with these specifications. The engineer shall advise the owner and grading contractor immediately if any unsatisfactory conditions are observed to exist and shall have the authority to reject the compacted filled ground until such time that corrective measures are taken, necessary to comply with the specifications. It shall be the sole responsibility of the grading contractor to achieve the specified degree of compaction. 2. Preparing Areas to be Filled (a) All brush, vegetation and any biodegradable refuse shall be removed or otherwise disposed of so as to leave the areas to be filled free of vegetation and debris. Any uncompacted filled ground or loose compressible natural ground shall be removed unless the report recommends otherwise. Any buried tanks or other structures shall be removed and the depression backfilled to the satisfaction of the engineer. (b) The natural ground which is determined to be satisfactory for the support of the filled ground shall then be plowed or scarified to a depth of at least 12 inches (12"). (c) After the natural ground has been prepared, it shall then be brought to the proper moisture content and compacted to not less than 90 percent of maximum dry density in accordance with ASTM D1557-91. ' (d) Where fills are made on slopes greater than 20 percent, horizontal benches shall be cut , into the firm natural ground. The initial bench at the toe of the fill shall be at least 15 feet in width on firm undisturbed natural ground. The width of all succeeding benches shall be at least 6 feet. • 0 APPENDIX A 2 3. Fill Materials All material shall be approved by the engineer and shall consist of materials free from vegetable matter, and other lumps greater than 6 inches in diameter. If, during grading operations, soils are found which were not encountered and tested in the preliminary investigation, tests on these soils shall be perfonned to detennine their physical characteristics. Any special treatment recommended in the preliminary or subsequent soils reports not covered herein shall become an addendum to these specifications. 4. Placing and Compacting Fill Materials (a) When the moisture content of. the fill material is below that specified, water shall be added until the moisture content is near optimum to assure uniform mixing and effective compaction. (b) When the moisture content of the fill materials is above that specified, the fill material shall be aerated by blading and scarifying or other satisfactory methods until the moisture content is near optimum as specified. ( c) After processing, the suitable fill materials shall be placed in layers which, when compacted, shall not exceed six inches (6"). Each layer shall be spread evenly and shall be thoroughly mixed during the spreading insure unifonnity of materials and moisture in each layer. (d) After each layer has been placed, mixed and spread evenly, it shall be thoroughly compacted to not less than the density set forth in paragraph 2 (c) above: Compaction shall be accomplished with approval types of compaction equipment. Rolling shall be accomplished while the fill material is at the specified moisture content. In place density tests shall be performed in accordance with ASTM D1556-90. (e) The surfaces of the fill slopes shall be compacted by means of sheepsfoot rollers or other suitable equipment. Compacting operations shall be continued until the slopes are stable and until there is no appreciable amount of loose soil on the slopes. 5. Inspection Sufficient inspection by our finn or the Soil's Engineer of record andlor his/her representative shall be maintained during the filling and compacting operations so that he/she can verify that the fill was constructed in accordance with the accepted specifications. 6. Seasonal Limits No fill material shall be placed, spread, or rolled if weather conditions increase the moisture content above permissible limits. When the work is interrupted by rain, fill op~J,:~tions shall not be resumed until the moisture content and densitY of fill are as previously specified, All recommendations presented in the attached report are a part of these specifications. 2 " . EAST COUNTY SOIL CONSULTATION AND ENGINEERING, INC. 10925 HARTLEY ROAD, SUITE I SANTEE, CALIFOR1'.UA 92071 (619) 258-7901 APPENDIXC RECO~ENDEDPROCEDURESFORSLABFOUNDATIONS BASED ON EXPANSION INDEX For soils that are expansive with respect to change in volume with change in moisture content, there is no economical way to absolutely prevent movement if there is a change in moisture content. Therefore, insofar as it is feasible, stable soil moisture content should be established and maintained throughout the life of the structures. Since it is usually not practical to maintain a completely stable soil moisture content, in order to minimize the undesirable effects of the expansive soils on the structures if these soils are placed or allowed to remain within the upper three feet ·below fmish grade, it is recommended that the following special precautions be exercised in design and construction of slabs and foundations. a. Design of foundations and slabs on expansive soils are presented in Table 1 based on expansion indices and there may be more stringent structural design or agency requirements. As an alternative to conventionally reinforced concrete foundations, post-tensioned structural slab systems,-designed by a structural engineer, may be utilized. b. Footing depth should be measured below lowest exterior finish grade. c. A reinforced concrete grade beam should be constructed across garage eI1:trances, with similar depth and reinforcement as adjacent perimeter footings for all soils with expansion potential greater than "very lown• d. For soil with a potential expansion greater than "low", interior isolated spread footings are not recommended. e. Where pre-saturation is recommended beneath interior slabs, the recommended moisture should penetrate to one foot below the. depth of the perimeter footings. Pre-saturation should be completed at least 24 hours prior to concrete placement. f. For soils with an expansive index greater than "low" slab reinforcement should be structurally tied to the footings. .' " APPENDIXC g. In buildings where it is feasible to permit independent movement of slabs with respect to foundations, such as in garages' and warehouses, these slabs should be separated from the foundations by II2-inch thickness of construction felt or equivalent. Special care should be exercised to assure that the separation extends to the full depth of the thickened edges of slab and that no appurtenances are attached to the building and also the slabs. h. Provide a moisture barrier, such as 10-mil visqueen overlain by 2 inches of sand below slabs in areas that receive flooring which might be adversely affected by capillary moisture. i. Where a base course is recommended beneath interior slabs, it should consist of pea gravel~ clean sand, or other acceptable granular material, i.e. a capillary break at least 4 inches.thick, consisting of sand, gravel or 3/4 inch crushed rock with no more than 5 percent passing the No. 200 sieve. The above moisture barrier/sand cover requirement may be included as part of the recommended base course thickness. j. Slab reinforcement should be supported at mid-slab height on chairs or concrete blocks. k. Provide positive drainage away from all perimeter footings to a horizontal distance of at least five feet outside the building walls. 2 r=========================~~~~~~~~~===~ • .. ' ~ ( . .. APPENDIXC FOOTINGS SLABS EXPANSION DEPTH BELOW GRADE INDEX REINFORCEMENT THICKNESS REINFORCEMENT PRE SATURATION BASE UBC 18-2 I-STORY 2-STORY COURSE 12 INCH 18 INCH 2 # 5 STEEL BARS # 3 BARS@ 18" OPTIMUM VERY LOW PERIMETER PERIMETER 1 TOP 4 INCHES ON CENTER MOISTURE . (0-20) 1 BOTIOM NOMINAL EACH WAY LOW 12 INCH 18 INCH (21-50) INTERIOR INTERIOR 4# 5 BARS MEDIUM 24 INCH 24 INCH 2 TOP #3BARS@12" 2 TO 4 PERCENT 4 (51-90) PERIMETER PERIMETER 2 BOTIOM 4 INCHES ON CENTER ABOVE INCHES OR NET EACH WAY OPTIMUM 18 INCH 18 INCH 2# 6 BARS INTERIOR INTERIOR 1 TOP 1 BOTIOM 4# 5 BARS HIGH 30 INCH 30 INCH 2 TOP #4BARS@16 3 TO 5 PERCENT 6 (91-130) PERIMETER PERIMETER 2 BOTIOM 5 INCHES INCHES ON ABOVE INCHES OR NET CENTEREACH OPTIMUM 18 INCH 18 INCH 2# 8 BARS WAY INTERIOR INTERIOR 1 TOP I BOTIOM 36 INCH 36 INCH 4# 6 BARS #4BARS@ 12 . 4 TO 6 PERCENT 6 VERY HIGH PERIMETER PERIMETER 2 TOP 6 INCHES INCHES ON ABOVE INCHES (> 131) 2 BOTIOM NET CENTEREACH OPTIMUM 30 INCH 30 INCH WAY INTERIOR INTERIOR I.r'., • . , 3