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255, Cut and fill slopes as reccomm, Studies & ReportsArchitecture 672 Silver Spur Road Neil Stanton Palmer Planning Palos Verdes Peninsula Member Engineering California 90274 American Institute Telephone (213) 377-6976 of Architects • Neil Stanton Palmer Architect,A.I.A. Incorporated February 2, 1981 Honorable Mayor and Members of the. Rolling Hills City Council Rolling Hills City Hall Rolling Hills, California 90274 Members of the Council Re: Goldberg Residence/Owner compromises to meet Art Jury and Planning Commission recommendations The Goldbergs have made extensive compromises in their planning in an effort to achieve harmony between the Art Jury and the Planning Commission and we feel that the plan agreed upon by all parties is a much better plan for the city and for the Goldbergs. However, it has increased the construction cost by approximately $125,000. The following list covers the major compromises made: 1. The cut and fill has been balanced as requested by the Art Jury thus eliminating 3,000 cubic feet of imported fill. 2. They have provided increased flat pad area around the house including play yard and terraces per Planning Commission's desires.. 3. The Goldbergs have completely rearranged their floor plan several times in order to accomodate the Art Jury and the Planning Commission's desires. 4. The overall size of the house has been reduced. 5. The Goldbergs have accepted a two car garage door with tandem parking rather than the three car garage previously planned for. 6. The house has been separated into two wings in order to allow for a pool patio on the pad level of the house. February 2, 1981 Page 2. 7. The house is stepped two and one half feet vertically across their 34' width in order to follow the terrain of land as much as possible. 8. The terrace level has been lowered one and one half feet below the living level of the house, to follow the terrain of the land and help balance the cut and fill. 9. The Goldbergs are providing for a vegetation screen between the house and Pine Tree Lane. 10. The terraces follow the shape ofthe allowable proposed grading in a manner that keeps the wall height on the terrace side to an average of two and one half feet high. Respectfully submitted, Neil Stanton alme r, AIA Principal Architect NSP/as Architecture 672 Silver Spur Road Neil Stanton Palmer Planning Palos Verdes Peninsula Member Engineering California 90274 American Institute Telephone (213) 377-6976 of Architects Neil Stanton Palmer Architect, A.I.A. Incorporated February 2, 1981 Honorable Mayor and Members of the Rolling Hills City Council Rolling Hills City Hall Rolling Hills, California 90274 Members of the Council Re: Goldberg Residence/Owner compromises to meet Art Jury and Planning Commission recommendations The Goldbergs have made extensive compromises in their planning in an effort to achieve harmony between the Art Jury and the Planning Commission and we feel that the plan agreed upon by all parties is.a much better plan for the city and for the Goldbergs. However, it has increased the construction cost by approximately $125,000. The following list covers the major compromises made: 1. The cut and fill has been balanced as requested by the Art Jury thus eliminating 3,000 cubic feet of imported fill. 2. They have provided increased flat pad area around the house including play yard and terraces per Planning Commission's desires.. 3. The Goldbergs have completely rearranged their floor plan several times in order to accomodate the Art Jury and the Planning Commission's desires. 4. The overall size of the house has been reduced. 5. The Goldbergs have accepted a two car garage door with tandem parking rather than the three car garage previously planned for. 6. The house has been separated into two wings in order to allow for a pool patio on the pad level of the house. February 2, 1981: Page 2. 7. The house is stepped two and one half feet vertically across their 34' width in order to follow the terrain of land as much as possible. 8. The terrace level has been lowered one and one half feet below the living level of the house, to follow the terrain of the land and help balance the cut and fill. 9. The Goldbergs are providing for a vegetation screen between the house and Pine Tree Lane. 10. The terraces follow the shape of the allowable proposed grading in a manner that keeps the wall height on the terrace side to an average of two and one half feet high. Respectfully submitted, Neil Stanton almer, AIA Principal Architect NSP/as • Architecture 672 Silver Spur Road Neil Stanton Palmer Planning Palos Verdes Peninsula Member Engineering California 90274 American Institute Telephone (213) 377-6976 of Architects Neil Stanton Palmer Arch itect, A.I.A. Incorporated February 2; 1981 Honorable Mayor and Members of the Rolling Hills City Council Rolling Hills City Hall Rolling Hills, California 90274 Members of the Council Re: Goldberg Residence/Owner compromises to meet Art Jury and Planning Commission recommendations The Goldbergs have made extensive compromises in their planning in an effort to achieve harmony between the Art Jury and the Planning Commission and we feel that the plan agreed upon by all parties is.a much better plan for the city and for the Goldbergs. However, it has increased the construction cost by approximately $125,000. The following list covers the major compromises made: 1. The cut and fill has been balanced as requested by the Art Jury thus eliminating 3,000 cubic feet of imported fill. 2. They have provided increased flat pad area around the house including play yard and terraces per Planning Commission's desires. 3. The Goldbergs have completely rearranged their floor plan several times in order to accomodate the Art Jury and the Planning Commission's desires. 4. The overall size of the house has been reduced. 5. The Goldbergs have accepted a two car garage door with tandem parking rather than the three car garage previously planned for. 6. The house has been separated into two wings in order to allow for a pool patio on the pad level of the house. • February 2., 1981 J_ j Page 2. 7. The house is stepped two and one half feet vertically across their 34' width in order to follow the terrain of landas much as possible. 8. The terrace level has been lowered one and one half feet below the living level of the house, to follow the terrain of the land and help balance the cut and fill. 9. The Goldbergs are providing for a vegetation screen between the house and Pine Tree Lane. 10. The terraces follow the shape of the allowable proposed grading in a manner that keeps the wall height on the terrace side to an average of two and one half feet high. Respectfully submitted, Neil Stanton Palmer, AIA Principal Architect NSP/as Architecture 672 Silver Spur Road Neil Stanton Palmer Planning Palos Verdes Peninsula Member Engineering California 90274 American Institute Telephone (213) 377-6976 of Architects Neil Stantbn Palmer Architect,A.I.A. Incorporated l) February 2, 1981 Honorable Mayor and Members of the Rolling Hills City Council Rolling Hills City Hall, Rolling Hills, California 90274 Members of the Council Re: Goldberg Residence/owner compromises to meet Art Jury and Planning Commission recommendations The Goldbergs have made extensive compromises in their planning in an effort to achieve harmony between the Art Jury and the Planning Commission and we feel that the plan agreed upon by all parties is.a much better plan for the city and for the Goldbergs. However, it has increased the construction cost by approximately $125,000. The following list covers the major compromises made: 1. The cut and fill has been balanced as requested by the Art Jury thus eliminating 3,000 cubic feet of imported fill. 2. They have provided increased flat pad area around the house including play yard and terraces per Planning Commission's desires.. 3. The Goldbergs have completely rearranged their floor plan several times in order to accomciate the Art Jury and the Planning Commission's desires. 4. The overall size of the house has been reduced. 5. The Goldbergs have accepted a two car garage door with tandem parking rather than the three car garage previously planned for. 6. The house has been separated into two wings in order to allow for a pool patio on the pad level of the house. February 2, 1981 Page 2. 7. The house is stepped two and one half feet vertically across their 34' width in order to follow the terrain of land as much as possible. 8. The terrace level has been lowered one and one half 'feet below the living level of the house, to follow the terrain of the land and help balance the cut and fill. 9. The Goldbergs are providing for a vegetation screen between the house and Pine Tree Lane. 10. The terraces follow the shape of the allowable proposed grading in a manner that keeps the wall height on the terrace side to an average of two and one half feet high. Respectfully submitted, Neil Stanton almer, AIA Principal Architect NSP/as III �,I 11111 R. BRUCE LOCKWOOD. R.E G. Lockwood -Singh & Associates A CORPORATION Consulting Foundation Engineers and Geologists 1944 Cotner Avenue • Los Angeles, California 90025 Telephone: (213) 870-7335; (213)477-8208 Project Ref. 2228-02 •' AWTAR SINGH, C.E. February 5, 1981 Mr. Martin Goldberg 1657 Cataluna Palos Verdes Estates, California 90274 SUBJECT: REPORT OF GEOTECHNICAL INVESTIGATION PROPOSED RESIDENTIAL CONSTRUCTION LOT 2, TRACT 28594 #4 PINE TREE LANE ROLLING HILLS, CALIFORNIA Dear Mr. Goldberg: In accordance with your request we are pleased to submit a report of a geotechnical investigation to provide ' information and recommendations for proposed residential construction at the address referenced above. The accompanying report has been substantiated by surface and subsurface exploration, geologic reconnaissance, and mathematical analysis made in accordance with generally accepted engineering practice, includingthose field and laboratory tests considered necessary in the circumstances. It is the professional opinion of the undersigned that this report presents fairly the information requested by you. Respectfully submitted, LOCKWOOD-SINGH & ASSOCIATES /�e-241 Rr Bruce Lockwood CEG 204 RBL/AS/CHP/SMD/TW:jmf Qt f Awtar Singh CE 17727 Proj. Ref. 2228-02 GOLDBERG - Pine Tree -2- February 5, 1981 • INTRODUCTION - This report presents the findings and conclusions of a geotechnical investigation of Lot 2, Tract 28594, No. 4 Pine Tree Lane, Rolling Hills, California. This investigationwas undertaken in order to evaluate soil and geologic conditions pertinent to future residential development, . The following report was reviewed during the course of our investigation: Engineering Geologic Investigation, Tentative Tract No. 28954, Rolling Hills, California, by Maurseth-Howe- Lockwood & Associates, October 30, 1970. Soil and geologic data are plotted on a 1"=16' Site Plan, dated January, 1981, provided by Neil Stanton Palmer Architect and included in this report as Plate A. Three geologic cross.. -sections were prepared at the same scale and are included herein as Plates B-1 through B-3. • Proj. Ref. 2228-02 GOLDBERG - Pine Tree -•3- February 5, 1981 • FIELD INVESTIGATION Field.. investigation included geologic reconnaissance of the subject property and surrounding areas and excavation of thirteen test pits with a crawler backhoe. Bulk and undisturbed samples of soil and bedrock were collected for subsequent laboratory testing. All test pits were backfilled following examination, logging, sampling and mapping. Logs of the Test Pits are included as Plates C-1 through C-13. • • Proj. Ref. 2228-02 GOLDBERG - Pine Tree -4- February 5, 1981 • SITE CONDITIONS Location and. Topography The subject site is located on a west -facing slope descending from Pine Tree Lane in the north -central portion of the Palos Verdes Hills. Elevations on the parcel range from about 775 feet to 920 feet above sea level. Slopes on the parcel range from about 1.2:1 to 5.7:1 (horizontal to vertical ratio). A north -trending drainage course parallels the western property boundary. The site had been disked shortly before the time of investigation. Drainage Surface drainage consists of sheet flow runoff of incident rainfall derived primarily from within the parcel boundaries. .A portion of the drainage course mentioned above has been 'designated.a flood hazard area by Los Angeles County, see Plate A. Drainage from upslope areas to the east of the parcel is effectively intercepted by Pine Tree Lane. No evidence of past erosion or surface instability due to concentrated runoff was observed. Ground Water At the time of investigation the drainage channel was dry. No evidence of near surface ground water was encountered on the slopes or in the test pits. No ground water is anticipated in the area of proposed development. • Proj. Ref. 2228-02 GOLDBERG - Pine Tree -5- February 5, 1981 • GEOLOGIC CONDITIONS Fill No fill was encountered on the site. Topsoil " The site is mantled by 2 feet to greater than 10 feet of dark brown clay topsoil as encountered in the test pits. At the time of investigationthe topsoil was dry and stiff. Bedrock Bedrock underlying the site consists of marine sediments of the Altamira member of the Miocene Monterey formation: The principal rock type is siltstone that ranges from massive to moderately well bedded. The siltstone is moderately well indurated and locally fractured. Proj. Ref. 2228-02 GOLDBERG - Pine.Tree -6- ' February 5, 1981 GEOLOGIC STRUCTURE AND STABILITY Bedding within the bedrock exhibits generally northerly dips of about 10° to 32°, essentially neutral to the existing westerly facing slope. Anomalous attitudes are attributed to localizedminor undulations in the bedding., a condition common throughout this portion of the Palos Verdes area. No evidence of past geologic instability was observed during this investigation. No unstable conditions are anticipated providing procedures and precautions customary to hillside construction are observed during and following development. • Proj. Ref. 2228-02 GOLDBERG - Pine Tree - 7-- February 5, 1981 • LABORATORY INVESTIGATION Laboratory testing was programmed following a review of the field.data and consideration of the probable foundation design to be evaluated. Laboratory testing includeddeterminations of unit weights, moisture contents, shear strengths, consolidation characteristics and swelling potential.. of in situ soils... The results of in -situ density tests are presented on Table I, TABLE I SUMMARY OF FIELD DENSITY DETERMINATIONS (From 2-3/8" 0 Undisturbed Samples) Test Soil In. Situ In Situ Location Type Dry Density Moisture Content TP-5 @ 4' Siltstone 78.6 pcf '15.8% TP-6 @ 1' Topsoil 84.0 pcf 20.2% TP-6 @ 4' Siltstone 79,1 pcf 19.0% Proj. Ref. 2228-02 GOLDBERG - Pine Tree -8- February 5, 1981 • Maximum density and optimum moisture contents of the on -site materials were determined in the laboratory in F " accordance with ASTM D 1557-70. Results are tabulated in Table II, "Summary of Laboratory Density Determinations." Samples,of the on -site materials were remolded to 90% relativecompaction at optimum moisture content, and were tested to determine the shear and consolidation characteristics of the in -situ soils and probable fill soil.. Direct shear tests were performed after the samples had been soaked for more than 48 hours. Results of the direct shear tests on the remolded samples are plotted on Plates D-1 and D-2. Consolidation curves of remolded samples are plotted on Plate E. TABLE I SUMMARY OF LABORATORY DENSITY DETERMINATIONS (Test Standard ASTM. D 1557-70) Optimum Maximum Dry Moisture Content - Soil 'Type Density (% Dry Wt.) Clay (Topsoil) 96.0 pcf 22.5% Clay, silty 89.0 pcf (Comminuted siltstone diatomaceous) • 28. 5% Proj. Ref. 2228-02 -9- February 5, 1981 GOLDBERG - Pine Tree To determine the expansiveness of the on -site materials, samples were remolded at 50% saturation and then allowed to absorb moisture under a surcharge of 144 psf. The on -site materials can be classified as moderately to highly expansive. The expansion index tests were performed in accordance with UBC Standard No. 29-2. The results are presented on Table III, "Summary of Expansion:Index Tests." TABLE III SUMMARY OF EXPANSION'INDEX TESTS Soil. Type Expansion Index Potential Expansion Clay (topsoil)' 106 High Clay,. silty 89 Medium to High diatomaceous (siltstone) Proj. Ref. 2228-02 GOLDBERG - Pine Tree -10- February 5, 1981 .SLOPE STABILITY ANALYSIS Proposed Cut Slopes in Bedrock: The stability of proposed cut slopes in bedrock with favorable dipping conditions has been analyzed by "Singh's Charts". The highest proposed cut slope is on the order of 25 feet and will be constructed at an inclination no steeper than 1.5:1 (horizontal to vertical ratio).. The following shear strength parameters have been assumed in the analysis, based on direct shear tests performed on samples of comminuted bedrock remolded to in -situ density and moisture content, and sheared under soaked conditions. Unit -Weight, y = 110 pcf Cohesion, C = 300 psf Angle of Internal Friction, 0.= 23° Based on the above values a factor -of -safety of 1.72 has been -obtained. Calculations are presented on Plate F. Proposed Fill Slopes: It is understood the present grading plan may be altered with regard to the location and heights of the proposed 1.5:1 (horizontal to vertical ratio) fill slopes. In addition, the shear strength parameters of theproposed import fill materials are not known. The safe recommended heights of proposed 1.5:1 fill slopes will be dependent upon the materials used in proposed compacted fills. • Proj. Ref. 2228-02 GOLDBERG - Pine Tree -11- February 5, 1981 • CONCLUSIONS AND RECOMMENDATIONS Based on the field. andlaboratoryinvestigation described herein, it is the professional opinion of the undersigned that the proposed construction is feasible, subject to the following specific recommendations. Discussion The site is mantled with highly expansive adobe clay topsoil to depths ranging from about.2 feet near the top of slope to approximately 10 feet near the lower reaches of the property. The topsoil and underlying siltstone, exhibit low shear strength parameters and when mixed together will not produce a fill material suitable for adequate structural support. It is recommended that fill be comprised of nomore than 25% topsoilwell mixed with comminuted bedrock. It is understood that some import fill_material may be required to balance the proposed site grading. -Since the proposed gradingwill expose bedrock in much of the proposed house area it is recommended that allfoundations for theresidence,pool., and structural walls be established in bedrock... Caisssons may be necessary where the depth to bedrock exceeds approximately 8 feet. Proj. Ref. 2228-02 GOLDBERG - Pine Tree -12- February 5, 1981 • Foundations No foundations shall be established in the topsoil or proposedfill soils. All foundations shall be established in the competent underlying bedrock. An allowable bearing value of 2000 psf may be assumed for .foundations established at least 24 inches in competent bedrock. The bearing value maybe increased by 500 psf for each additional foot of foundation in competent bedrock..to_a maximum of 3000 psf. The underlying bedrock is moderately to highly expansive. Continuous foundations shall, be reinforcedwith at least 2 No...4 bars located near the top and bottom of the footing. Pier footings are not recommended.. Lateral Design An allowable lateralbearing value of 500 psf may be assumed per foot of foundation. placed .in competent bedrock to a maximum of 2000 psf. .A friction factor of 0.35 may be assumed: Frictional and lateral resistances may be combined, provided the lateral bearing resistance does not exceed 2/3 of allowable bearing.. The above values may be increased by one-third for short durations of seismic and wind forces. Set Back. for Foundations The outer face of the bottom of all foundations shall be set back a. minimum distance of 5 feet from the face of the slope. • Proj. Ref. 2228-02 GOLDBERG - Pine Tree -13- February 5, 1981 Settlement If the entire building is founded in undisturbed bedrock, as recommended., settlement of 1/2 inch may be anticipated. Overall differential settlement should be on the order of 1/4 inch.. Creep Downslope creep in the top.3 feet of the soil may be anticipated. In this connection,foundations and their structural connections shall be designed for lateral loads which maybe assumed as 1.0 kips/sq. ft. for placing on a slope steeper than 5 horizontal to 1 vertical. For design purposes, the creepload may be assumed to apply uniformly in the top 3 feet of soil. Drainage Adequate site drainage shall be designed by the civil engineer. In no case shall water be allowed.to pond within the site or be drained down the slope in an uncontrolled and concentrated manner. Slope Recommendations The existing slope is considered to be geologically grossly stable for the intended use. Proposed cut slopes may be constructed no steeper than 2:1 (horizontal to vertical ratio) in the topsoil and no steeper'than,1.5:1 in the bedrock. Proposed fillslopes may be constructed at aninclination of--. 1.5:1 to safe recommended heights.: :. Proj. Ref. 2228-02 GOLDBERG - Pine Tree -14- February 5, 1981 • • i.t should be understood that, required slope stability analysis for proposed.1.5:1 fill slopes will be provided when the final grading plan is available and the shear parameters of the proposed -import fill materials are known. Earth Pressure Walls retaining backfill of various materials may be designed for earth pressures equivalent to those exerted by .a fluid having a density not less than that shown in the following table: Equivalent Fluid Pressure Backfill. Backfill made up Surface Slope of composed of free -draining materials Retained Material of existing.. .. with top ofwedge at least (horz.: to vert.) site material".,. _. 6/10 of height of wall Level 45 30 5 to 1 48 33 4 to 1 53 35 3 to 1 58 38 2 to 1 65.. 43 12 to 1 80 55 Backfill of drained soils shall have a width at the top of the wedge equal to at least 6/10 of the height of the wall. The equivalentfluid pressures shall be increased in the event of surcharge affecting the wall. A drainage. blanket and weep holes shall _be.incorporated in the retaining wall design.. Proj. Ref. 2228-02 -:L5- February 5, 1981 GOLDBERG - Pine Tree Recommended creep forces do not apply to walls designed in accordancewith the above.equivalent fluid pressures. F '• Slabs Since the site soils and bedrocks are expansive', seasonal moisture changes can causesignificant strains in the floor systems, resultingin undesirable cracking. .The following floor systems are recommended in order of preference. 1. First preference.- Conventional wood floors 2. Second preference - Ifslabs on grade are used, they shall be supported by a minimum thickness of two feet of granular nonexpansive soil in order to minimize the effects of the underlying.. expansive soils. Such slabs shall have a minimum thickness of four inches and be reinforced withat least No. 3 bars spaced at 24 inches on center both ways, or 6x6-6/6 WWF. At a minimum No. 3 bars at 24 inches shall be provided in the exterior footings and bent three.feet into slabs. A moisture barrier consisting of at least four inches of crushed rock, or a plastic waterproof vapor barrier, such asvinyl with a thickness of at least six mils, is recommended for placement beneath the slab to prevent upward capillary movement of soil moisture. The compacted subgrade.soiis.up to 30 inches below lowest adjacent floor slabs and paving shall be premoistened to at least 120% of the optimum moisture content. The placement and compaction of granular subgrade soils shall_ • Proj. Rey. 2228-02 GOLDBERG - Pine Tree -16- February 5, 1981 be under the observationof the soils engineer. No significant distress to the slabs is anticipated. 3. Third.preference -.Slabs on -grade may be supported by a lesser thickness of granular:nonexpansive soil, to a minimumthickness.of•four inches. Slabs constructed in this mariner may be subject to some cracking, but this condition is not anticipated to cause any gross instability to the structure. Regular maintenance may be required. All other recommendations, with respect to reinforcement, waterproof barrier, and premoistening of, the subgrade soils. shall be followed as in Paragraph 2, above. Grading It is understoodthat grading is.planned at the site. Any and all grading shall be approved in advance by the soil engineer -land engineering_ geologist and shall be accomplished in accoi.dance with grading specifications contained elsewhere in this report. All proposed import soils shall be approved by. the soil engineer prior to construction. Temporary. Excavation. Slopes Tem ora� excavation slopes in the existing materials may be P Y made near vertical for cuts of less than 5 feet. For deeper cuts,..temporary excavation slopes shall be made no steeper thanlllil (horizontal to vertical). In areas where soils with little or no binder are encountered, shoring or flatter excavation slopes shall be made. Proj. Ref. 2228-02 -17-- February 5, 1981 GOLDBERG - Pine Tree All' excavations shall be made in accordance withthe regulations of th.e State of California Division of Industrial Safety. These recommended temporary excavation slopes do not preclude local raveling -and sloughing. Grading Specifications 1. Prior to placement of. compacted fill, the site shall be cleared of all vegetation, loose topsoil, debris, and any other deleterious materials. 2. If properly mixed, the existing site soils may be used in the compacted fill. Proposed fills shall contain no more than 25% topsoil. Surfaces receiving fill soils shall be scarified, aerated or moistened to moisturecontent acceptable to the soils engineer. 4. If the moisture content of the fill soilsis below the limits specified by the soils engineer, water shall be added until the moisture content is as required. 5. If the moisture content of the fill soils is above the limits specified by the soils engineer, the fill shall be aerated by blading or other satisfactory methods until the moisture content is as required. The wet soils may be mixed with drier materials to achieve an acceptable moisture content. • Proj. Ref. 2228-02 GOLDBERG - Pine Tree -1.8- February 5, 1981 • 6.. Natural slopes steeper than.5 horizontal to 1 vertical shall be benched into competent bedrock prior to f. placement of fill. The toes of -all ,proposed fill slopes shallbe provided with_a 12-foot wide keyway extending at least 3 feet into competent bedrock on the downslope side of the key. 7. All fill soils shall be placed in lifts such that after compaction they do notexceed six •(6) inches in thickness and compacted until field density tests indicate that a compaction... of not less than 900 of the maximum density as determined by ASTM D 1557-70 has been obtained. 8. Field density tests shall be made in accordance with ASTM D 1556-64. Field_. density tests shall be made for every 2 foot interval and -not less than one test shall be performed for every 500 cubic yards of fill placed. 9. Rocks less than 6 inches ingreatest dimension may be placed in the fill, provided: a. They are not placed in concentrated' pockets. b. The fine-grained materials surrounding the rocks are sufficiently compacted. 10. Rocks larger than 6 inches in greatest dimension shall be removed from the site or placed in accordance with specific recommendationsof the soils engineer. Proj. Ref. 2228-02 GOLDBERG - Pine Tree -19- February 5, 1981 • 11. No 'fill.soils shall be placed during unfavorable weather conditions. When work is interrupted by rains, fill operations shall not be resumed untilEthe field tests by the soils engineer indicate that the moisture content and. density of the fill are as previously specified. 12. .Planting and irrigation ofslopes and installation of erosion control and drainage devices shall comply with the requirements of the Grading Code of controlling agencies. • Proj. Ref. 2228-02 -20-• February 5, 1981 GOLDBERG - Pine Tree • Inspection As a necessary requisite to'.the use. of thi`s•report, the following shall be observed by the soils engineer or the engineering geologist. 1. Inspection of all foundation. excavations. 2. Inspection andtesting of all grading and compaction. 3. .Inspection of drainage blanket and weep holes for f retaining walls. 4. Geologic inspection to verify absence of adverse geologic conditions. The consultants should be notified at least 2 days in advance of the start of construction. .A joint meeting. between the client, contractor, and soil and geology consultants is recommended prior to the start of construction to discuss specific procedures and scheduling. • Proj. Ref. 2228-02 GOLDBERG - Pine Tree -21- February 5, 1981 • REMARKS The conclusions and recommendations contained herein are based on the surface examinationand findings and observations• at the test pit locations. Although no significant variations in soil orbedrock conditions are anticipated, if conditions are encountered during construction which appear to be different from those disclosed by the exploratory work, this office shall be notified so as to consider the need for modifications. All slope' geometry described .herein .is based upon visual examination in the field, or the cited topographic map. The ground slope is described sin context of underlying soil and geologic conditions'pri.marily for the purpose of evaluating slope stability, and should not be relied upon as a survey.- Where topographic data is important to the _.. location or size of proposed slopes; or structures such as retaining walls, the topographyshould be checked independently by the project Civil Engineers. Your attention is directed to the face that while caving was not encountered, it is possible that a trench or excavation would react in an entirely different manner. All shoring and bracing shall be in accordance with the current requirements of the State of California Division of Industrial Safety, and other public agencies having jurisdiction. The report is subject to review by controlling public agencies' having jurisdiction. • LOG OF TEST PIT 0'-2' TOPSOIL Clay Brown, stiff, dry, expansive; rock up °to 6" O and 10% in content. • 2'-5' BEDROCK (Tma) Siltstone Buff to red brown, massive, jointed, sandy, dry, moderately indurated.... Strike & Dip of Joints: N39E, 84°NW; E-W,75°S GEOLOGIC SKETCH Apparent Dip of Joint Set N62°E Test Pit Outline EQUIPMENT Crawler Backhoe w/24" bucket TEST • PIT No. 1 • SURFACE ELEVATION 844 GOLDBERG - Pine Tree DATE LOGGED 12Dec80 Iby CEP PROJECT No. 2228-02 LOCKWOOD - SINGH e ASSOC. PLATE c-i LOG OF TEST PIT 0'-l' TOPSOIL Clay Brown, stiff, dry, sandy, expansive. V-4' BEDROCK (.'aria) Siltstone Orange, massive, jointed, sandy, dry, moderately indurated. Strike & Dip of Joints: N15°E, vertical; N78°W, vertical EQUIPMENT GEOLOGIC SKETCH Tops° Vertical Joint Sets Crawler Backhoe w/24" bucket SURFACE ELEVATION 858_: N30°E Tma Test Pit Outline TEST PIT No. GOT,nRERG - Pine Tree 2 DATE LOGGED .12Dec80 {by CHP PROJECT No. 2228-02 LOCKWOOD - SINGH e ASSOC. • - ' PLATE C-2 l .0-.2- LOG OF TEST PIT • • 0'-3' .TOPSOIL Clay Dark brawn, stiff, dry, expansive, rock up to 6"0 and 1% in content. BEDROCK (7Yna) Siltstone Light brown, massive, jointed, moderately indurated. Sandy, dry. Strike & Dip of Joint: N36°E, 77°NW Joint GEOLOGIC SKETCH Test Pit Outline EQUIPMENT Crawler Backhoe w/24" bucket SURFACE ELEVATION 871 DATE LOGGED .12Dec80 • IY . CHP LOCKWOOD - SINGH e ASSOC. N12°W TEST PIT No. GOLDBERG - Pine Tree PROJECT No. 3 2228-02 - PLATE C-3 C-3. LOG OF TEST PIT, • • 0'-2' TOPSOIL 2'- Clay Brawn, sandy, dry, stiff, expansive, rock up to 8"0 and 15% in content BEDROCK ('aria) Siltstone Light orange brcrwn,.moderately indurated, sandy, moist, very poorly bedded. Strike & Dip of Bedding: N70°W,12°NE GEOLOGIC SKETCH Bedding N70°E Test Pit Outline EQUIPMENT Crawler Backhoe w/24" bucket I TEST PIT No. 4 SURFACE ELEVATION 905 DATE LOGGED'12Dec80 lby cap PROJECT No. 2228-02 LOCKWOOD - S INGH e ASSOC. GOLDBERG - Pine Tree PLATE C-4 LOG OF TEST PIT • • 0'-4' TOPSOIL Clay Brown, stiff, dry, expansive, san 4'-5' BEDS Oltna) Siltstone Light brawn, dry,. massive, moderately indurated, fractured, no bedding observed. GEOLOGIC SKETCH Topsoil Bedrock Test Pit Outline EQUIPMENT crawler Backhoe w/24" bucket SURFACE ELEVATION 875 DATE LOGGED .-1213ec80 Iby CRP LOCKWOOD - SINGH € ASSOC. TEST PIT No. GOLDBERG - Pine Tree PROJECT No. N40°E 2228-02 5 PLATE C-5 LOG OF TEST PIT 0'-2' TOPSOIL Clay Brown, stiff, dry, expansive sandy, rock up to 1'0 & 5% in content. 2'-4' BEDROCK ('Irna) Strike Strike Siltstone White, very poorly bedded, fractured, diatomaceous, moist Dip of Bedding: N85°W,32°NE Dip of Joint: N321W,72°SW GEOLOGIC SKETCH Topsoil N45°E Joint Test Pit Outline BM i ng EQUIPMENT Crawlerhoe w/24" bucket TEST PIT No. 6 SURFACE ELEVATION 983 GOLDBERG - Pine Tree DATE LOGGED 12Dec80 Jby CBP PROJECT No. 2228-02 LOCKWOOD - SINGH € ASSOC. PLATE C-6 C-6- LOG OF TEST PIT • • 0'-3' TOPSOIL Clay Stiff, Hoist, black, sandy, rock up to 1% in content and 2" 0 " 3' -5' BEDROCK (Ina) Siltstone Orange brown, moderately bedded, sandy, moderately indurated, moist Strike & Dip of Bedding: N60°E,25°NW GEOLOGIC SKETCH Test Pit Outline EQUIPMENT Crawler Hoe w/24" Bucket SURFACE ELEVATION 878 DATE LOGGED ' 12Dec80 lby CHP LOCKWOOD - SINGH e ASSOC. Bedding TEST PIT No., N80°E GOLDBERG - Pine Tree PROJECT No. 2228-02 PLATE c-7 6-- 7' LOG OF TEST PIT • 0' - 1' - 4' 110PSOIL Clay Brawn, stiff, sandy, dry, expansive, rock up to 6" 0 and 2% in content BEDROCK Cana) Siltstone Moderately bedded, moderately indurated, massive, siliceous dry 1'-3' white, 3'-4' orange brown - Strike & Dip of Joints: N71°E,72°SE; N65°E,62°SE; N70°W,69°NE GEOLOGIC SKETCH Topsoil Joint Set EQUIPMENT Crawler Hoe w/24" bucket • SURFACE ELEVATION 873. DATE LOGGED 1.2Dec80 IbY. CHP N48 E Test Pit Outline TEST PIT No. 8 GOLDBERG - Pine Tree PROJECT No. 2228-02 LOCKWOOD - SINGH € ASSOC. - PLATE c-8 • 2?' - 51' LOG OF TEST PIT Clay Brown, sandy, dry, expansive, stiff BEDROCK Ma) Siltstone Very sandy, dry, fractured, massive i Strike' & Dip of Joints: N87°E,62°SE; N18°W, 83°NE GEOLOGIC SKETCH Test Pit Outline Joint Set N60°E EQUIPMENTi, Crawler Hoe w/24" bucket TEST PIT No. 9 • SURFACE ELEVATION 849 GOLDBERG - Pine Tree . DATE LOGGED 12Sept80 Iby (HP PROJECT No. 2228-02 LOCKWOOD - SINGH € ASSOC. PLATE c-9 9 LOG OF TEST PIT 0'-1' 1'-5' ZUPSOIL Clay Brown, sandy, expansive, dry, stiff rock fragments 1 % to 1" 0 ` BEDROCK (TYna) Siltstone Moderately bedded,. white to orange brown, dry, moderately indurated. Strike Dip of Bedding: N68°W,10°NE GEOLOGIC SKETCH Test Pit Outline N87°E Bedding EQUIPMENT Crawler Hoe w/24" Bucket TEST PIT No. 10 SURFACE ELEVATION 865 GOLDBERG - Pine Tree' DATE LOGGED 12Sept80 IbY CHp PROJECT No. 2228-02 LOCKWOOD - SINGH e ASSOC. PLATE c-lo LOG OF TEST PIT 1/2'-3 'IoPSOIL Clay Stiff, dry, expansive, sandy, brown BEDROCK ('Iola) Siltstone Dry, moderately bedded, moderately indurated, sandy orange brawn to white Strike & Dip of Bedding: E W, 24°N ' GEOLOGIC SKETCH TOpr Test Pit Outline Bedding Bedrock N70°E EQUIPMENT' ICr ler 24" .Bucket TEST PIT No. 11 aw Hoe w/ SURFACE ELEVATION 845 GOLDBERG - Pine Tree DATE LOGGED 12Sept80 ,by CHP PROJECT No. 2228-02 LOCKWOOD - S INGH e ASSOC. PLATE c-ii LOG OF TEST PIT • 0' -1 ! TOPSOIL i Clay Sandy, silty, brawn, moist, soft, expansive h' -4' BEDROCK ('Tha) Siltstone Siliceous, hard, diatomaceous, poorly bedded, white to orange brown, dry Strikel& Dip g of Bedding: N28°W,11°tE GEOLOGIC SKETCH Test Pit Outline soil B9rock Bedding N50°E EQUIPMENT crawler Hoe w/24" Bucket TEST PIT No. 12 III SURFACE ELEVATION 833 GOLDBERG - Pine Tree . DATE LOGGED 12Dec80 - Iby CHP PROJECT No. • 2228-02 LOCKWOOD-SINGH E ASSOC. PLATE c-1: c- iL LOG OF TEST PIT • 0'-2' FILL 2'-8' 8'-10' Clay Brown, soft, expansive, concrete cracks up to 2'0 F 1, TOPSOIL 1 r Clay Brown, stiff, dry, sandy, expansive, rock fragments up to 1' 0 and 1% in content BEDROCK (Tina) Siltstone Orange, dry, moderately bedded, moderately indurated sandy Strike & Dip of Bedding: N20°K,10°NE Concretes Rock Test Pit Outline GEOLOGIC SKETCH Fill Topsoil Bedding N220E EQUIPMENT Crawler Hoe w/24" bucket TEST PIT No. 13 • SURFACE ELEVATION 808 .. GOT,DRERG Pine Tree DATE LOGGED 12Ded80 Iby cuP PROJECT No. 2228-02 LOCKWOOD - SINGH € ASSOC. PLATE C-13 DIRECT SHEAR TEST PLOT NORMAL LOAD - kips per square foot 0' 2 3 4 5 6 J111 IIII 1111 1111 1111 1111 1111 1111 1111 II11'II11 MIL' 6 5 o - o - - cu o _ Cr 7 '4 - a I - 3- I= z _ CC - I— cn Q U) -- I O 111111111 1111 1111 1111 1111 1111 1111 1111 1111 1111 11117 TP-,6 @ 0'-2': Topsoil (clay) remolded to 90% relative compaction at optimum moisture content and soaked to approximate saturated conditions. Initial Dry Density = 86.4 pcf Initial MoistureContent = 22.5 % Adopted Ultimate ShPAr Strength Parameters: C = 400 psf 0 = 13° PROJECT GOLDBERG - Pine Tree NO' DATE February, 19s1 2228-02 PLATE D-1 ILOCKWOOD - SINGH & ASSOCIATES DIRECT SHEAR TEST PLOT 0 III o - 0 ci NORMAL LOAD = kips per square foot 2 3 4 5 6 I IIII IIII IIII IIII IIII IIII IIII IIII IIII1111 III I 0-l11ll Iil1 IIII I111 I111 IIII till IIII I111 11;1 III' TP-6 @ 2'-4': Comminuted siltstone remolded to 90% relative compaction at optimum moisture content and soaked to approximate saturated conditions. Initial. Dry Density = 80.1 pcf Initial Moisture Content = 28.5% Adopted Ultimate Shear Strength Parameters: C = 300 psf f6 = 23° PROJECT GOLDBERG - Pine Tree Lane N0. 2228-02 DATE February, 1981 PLATE n_2- LOCKWOOD - SINGH & ASSOCIATES CONSOLIDATION TEST PLOT • 1 3 4 z5 0 a 0 6 J 0 7 0 8 F— • z W 9 U cc W °-10 11 12 13 14 NORMAL LOAD- . 3 .4 .5 .6 .7.8.9 • o sample at initial moisture content ()sample after saturation TP-6 @ 2'-4': Siltstone remolded to 90% Cp = 40 PROJECT GOLDBERG Pine Tree Lane N O. 2228-02 kips per square foot 2 3 4 5 6 7890 DATE February, 1981 PLATE E LOCKWOOD - SI NGH & ASSOCIATES 0.6 BASED ON TAYLOR'S CHARTS 65 0.4, 0 I.5 GIVEN c AND 4) OF SOIL AND y AND H OF THE SLOPE PLOT POINT c/yH, 4) - AND READ FACTOR OF SA :ET'''. NF.S.= 3.0 2.5 �� —SAME CRITICAL SURFACE LINES 10 • 20 30 c , DEGREES 0 2.3 . 40 50 From: Singh,,Awtar, "Shear Strength and Stability of Man -Made Slopes" Journal of the Soil Mechanics and Foundation Division, ASCE SM6, November 1970, pp. 1879-1892 S \ LTS7t.tE: 11.9 2 S -�u- I I 1.5:1 Cut Slope in Bp1rock Proj. GOLDBERG - Pine Tree No. 2228-02 Date February, 1981 • PLATE F LOCKWOOD-SINGH & AS IA'1'ES