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Home My WebLink AboutCT 01-08; NORTH POINTE WEST; VERIFICATION OF GEOTECHNICAL SERVICES; 2002-06-18W CHRISTIAN WHEELER ENGINEEkING June 18, 2002 Caritas Development Company CWE 201.615.10 5600 Avenida Encinas, Suite 100 Carlsbad, California 92008 Attention: John White SUBJECT: VERIFICATION OF GEOTECHNICAL SERVICES, NORTH POINTE WEST BUILDINGS 5, 6,7, and 8, CORTE DE LA PINA, CARLSBAD, CALIFORNIA. C.T. 01-08 Reference: "Update Geotechnical Report, North Pointe West, Corte de la Pina and El Camino Real, Carlsbad, California," by Christian Wheeler Engineering, dated September, 24, 2001 Ladies/Gentlemen, This letter is written to confirm that Christian Wheeler Engineering has provided geotechnical observation and testing services on a continuous basis during the mass grading performed on Building Pad Numbers 5, 6, 7, and 8 at the subject site. CONCLUSIONS Based upon our tests and observations, it is our opinion that the earthwork was performed substantially in compliance with the recommendations presented in the above referenced report, the City of Carlsbad grading requirements, and the Uniform Building Code. It is our further opinion that the building pads are suitable for the support of the proposed buildings. Our recommendations for the minimum design of foundations are presented in the following paragraphs. FOUNDATIONS GENERAL: It is our opinion that the proposed tilt-up structures may be supported by conventional continuous and spread footings. Expansion index tests performed in our laboratory indicate that the foundation soils for the proposed buildings have a moderate potential for expansion; the recommendations presented herein reflect this condition. 4925 Mercury Street + San Diego, CA 92111 + 858-496-9760 + FAX 858 -496-9758 p.. 201.615.10 June 18, 2002 Page 2 CONVENTIONAL FOUNDATIONS: Conventional continuous and spread footings supporting the proposed structures should be founded at least 18 inches below the lowest adjacent finished grade. Continuous footings should have a minimum width of 12 inches. Horizontal dimensions of isolated footings should be at least 24 inches by 24 inches. BEARING CAPACITY: Conventional footings with the above minimum dimensions may be designed for an allowable soil bearing pressure of 2,500 pounds per square foot. This value may be increased by one-third for combinations of temporary loads such as those due to wind or seismic loads. FOOTING REINFORCING: Reinforcement requirements for foundations should be provided by the project structural engineer. However, based on the existing soil conditions, we recommend that the minimum reinforcing for continuous footings consist of at least two No. 5 bars positioned three inches above the bottom of the footing and two No. 5 bars positioned two inches below the top of the footing. LATERAL LOAD RESISTANCE: Lateral loads against foundations may be resisted by friction between the bottom of the footing and the supporting soil, and by the passive pressure against the footing. The coefficient of friction between concrete and soil may be considered to be 0.35. The passive resistance may be considered to be equal to an equivalent fluid weight of 350 pounds per cubic foot. This assumes the footings are cast tight against undisturbed soils. If a combination of the passive pressure and friction is used, the friction value should be reduced by one-third. FOUNDATION EXCAVATION OBSERVATION: All foundation excavations should be observed by the Geotechnical Consultant prior to placing concrete to determine if the foundation recommendations presented herein are complied with. All footing excavations should be excavated neat, level and square. All loose or unsuitable material should be removed prior to the placement of concrete. ON-GRADE SLABS INTERIOR FLOOR SLABS: The minimum floor slab thickness should be four inches. The floor slab should be reinforced with at least No. 3 bars placed at 18 inches on center each way. Slab reinforcing should be positioned on chairs at mid-height in the floor slab. MOISTURE PROTECTION FOR INTERIOR SLABS: Where the concrete on-grade floor slabs will support moisture-sensitive floor covering, it should be underlain by a moisture barrier. We recommend that the minimum configuration of the subslab moisture barrier consist of a four-inch-thick blanket of coarse, clean sand. The moisture barrier material should have 100 percent material passing the '/4 -inch sieve and less than ten percent and five percent passing the No. 100 and No. 200 sieves, respectively. A visqueen vapor barrier should be placed in the center of the moisture protection blanket. 201.615.10 June l8,2002 Page EXTERIOR CONCRETE FLATWORK Exterior slabs should have a minimum thickness of four inches. Reinforcement and control joints should be constructed in exterior concrete flatwork to reduce the potential for cracking and movement. Spacing of control joints should be in accordance with the American Concrete Institute specifications. When exterior slabs abut perimeter foundations they should be doweled into the footings. The rough grading of other areas of the project is in progress. A formal report presenting a summary of our observations and tests will be prepared and submitted upon the completion of the rough grading work. If you should have any questions about the services provided on the project by our firm, please do not hesitate to contact our office. This opportunity to be of professional service on your project is sincerely appreciated. Respectfully submitted, CHRISTIAN WHEELER ENGINEERING Charles H. Christian, R.G.E. 00215 90 No. GE215 rM Exp. 9-30-05 CHC/DH/hf cc: (2) Submitted (4) Lusardi Construction SUMMARY OF TESTS Project: North Pointe West MASS GRADING Re1tiv Comnictinn Tests ASTM D2922.-91 Test No. Date Location Elev. (feet) Soil Type Moisture (%) Dry Density (pcf) Max. Density % Rel. ComjD. 60 5/24/2002 Building Pad #5 FG 16 - 13.8 110.3 117.0 94.3 61 5/24/2002 Building Pad #5 I FG 16 14.3 108.7 117.0 92.9 62 5/29/2002 Building Pad#7West End - 268.0 16 14.7 108.1 117.0 92.4 63 5/29/2002 Building Pad #7 West End 268.0 16 14.2 107.5 117.0 91.9 64 5/29/2002 Building Pad #7 West End 270.0 16 14.4 107.2 117.0 91.6 65 5/29/2002 1 Building Pad #7 West End 270.0 16 14.2 106.6 117.0 91.1 66 5/29/2002 Buildin& Pad #8 West End 270.0 16 13.6 107.9 117.0 92.2 67 5/29/2002 Buildin& Pad #8West End 270.0 16 14.4 106.3 117.0 90.9 68 - 5/29/2002 Building Pad #7 272.0 16 13.9 106.9 117.0 91.4 69 5/29/2002 Budding Pad #7 272.0 16 13.6 106.7 117.0 91.2 70 J5/29/2002 Building Pad #7 272.0 - 16 15.2 108.0 117.0 92.3 71 I 5/29/2002 Building Pad - 272.0 16 14.5 108.4 117.0 92.6 72 5/29/2002 1 Building Pad #7 272.0 16 14.7 106.8 117.0 91.3 73 5/29/2002 Building Pad #7 272.0 16 142 1062 117.0 90.8 74 1 5/29/2002 Building Pad #7 272.0 16 15.1 105.9 117.0 90.5 75 5/29/2002 Building Pad #7 FG 16 14.4 107.1 117.0 91.5 76 . 5/30/2002 Building Pad #5 Finish Grade FG 16 13.3 107.7 117.0 92.1 = 5/30/2002 Building Pad #5 Finish Grade FG 16 13.0 108.4 117.0 92.6 78 1 79 5/30/2002 I 5/30/2002 Building 5 Finish Grade Building Pad #5 Finish Grade FG FG 16 16 12.6 13.4 110.1 107.5 117.0 117.0 94.1 91.9 80 1 5/30/2002 Building Pad #5 Finish Grade FG 16 13.2 108.6 117.0 92.8 81 1 82 5/30/2002 5/30/2002 Buil&Pad #5 Finish Grade Building Pad #8 Finish Grade FG FG 16 16 12.4 12.6 109.3 107.9 117.0 117.0 24. 92.2 83 5/30/2002 Building Pad #8 Finish Grade FG 16 12.8 - 108.6 110 92.8 84 5/30/2002 Pad #8 Finish Grade _Building FG 16 13.1 108.9 117.0 .911 85 5/30/2002 Building Pad#8FinishGrade FG 16 13.5 108.2 117.0 - 92.5 861 5/30/2002[ Building Pad#8FinishGrade FG 16 13.9 107.6 117.0 92.0 87 5/30/2002 Building Pad #8 Finish Grade FG 16 12.7 109.3 117.0 93.4 98 1 6/6/2002 [ Building Pad #6 FG 16 12.3 106.6 117.0 91.1 99 6/6/2002 I Building Pad #7 FG 16 13.1 109.8 117.0 93.8 * This report only includes tests from building pads 5, 6, 7, and 8. MAXIMUM DRY DENSITY and OPTIMUM MOISTURE CONTENT ASTM 1557-91 Soil Type Description USCS Class Optimum Moisture (%) Maximum Dry Density(pcf) 16 Yellowish-tan, VERY SILTY CLAY, with sand CL 12.2 117.0 CWE 201.615.10 Plate 1 fr FROM :CHRISTIAN WHEELER ENGINEERING FAX NO. :8584969758 Jun. 03 2002 07:57AM P2/4 M! CHRISTIAN WI I[EL[ft ENGIN [[RING June 3, 2002 Carltas Development Company CWE 201415.8 5600 Avenida Endraic, Suite 100 Carlsbad, California 92008 Atttaitic,n John White SUBJECT: VERIFICATION OF GEOTECHNICAL SERVICES, NORTH POINTE WEST BUILDING 1, CORTE DE LA PINA, CARLSBAD, CALIFORNIA. C.T. 01-08 Reference: "Update Geotechnical Report, North Pointe West, Corte k la Pina and El Camino Real, Carlsbad, California," byChristian 'Whcvlct Engineering, darcdSeptember, 24, 2001 Ladies/Gentlemen, This letter is written to confirm that Christian Wheeler Rnginecring has provided geotechnical observation and testing aervicas on a continuous basis during the mass grading performed on Building Pad Number I at the subject site CONCLUSIONS Based upon our tests and observations, it is our opinion that the earthwork was performed substantially in compliance with the recommendations presented in the above referenced report. the City of Carlsbad grading requirements, and the Uniform Building Code. It is our further opinion that the building pad is suitable for the support of the proposed buildings. Our recommendations for the niitlimum design of foundations are presented in the following paragraphs. FOUNDATIONS GENERAL: It is our opinion that the proposed tilt-up structures may be supported by conventional continuous and spread footings. Expansion index tests performed in our laboratory indicate that the foundation soils for the proposed buildings have a moderate potential for expansion; the recommendations presented herein reflect this condition. 4925 McrcJry Street + San Diego, CA 92111 • g58-4969760 + FAX 858-496-9758 FROM :CHRISTIAN WHEELER ENGINEERING FAX NO. :8584969758 Jun. 83 2002 07:57AM P3/4 201.615.8 June 3,2002 Page CONVENTIONAL FOUNDATIONS; Conventional continuous and spread footings supporting the proposed structures should be founded at least 18 inches below the lowest adjacent finished grade. Continuous footings should have it minimum width of 12 inches. Horisontal dimensions of isolated footings should be at least 24 inches by 24 inches. BEARING CAPACITY. Conventional footings with the above minicrwxn dimensions may be designed for an allowabic soil bearing p.tcssute of 2,500 pounds per square foot. This value may be increased by one-third for combinations of temporary loads such as those due to wind or seismic loads. FOOTING REINFORCING: Reinforcement requirements for foundations should be provided by the project structural engineer. However, based on the existing soil conditions, we recommend that the minimum rein forcing for continuous footings consist of at least two No. S bars positioned three inches above the bottom of the footing and two No. 5 bate positioned two inches below the top of the footing. LATERAL LOAD RESISTANCE: Lateral loads against foundations may be resisted by friction between the bottom of the footing and the supporting soil, and by the passive pressure against the footing. The coefficient of friction between concrete and soil may be considered to be 0.35. The passive resistance may be considered to be equal to an equivalent fluid weight of 350 pounds per cubic foot. This assumes the footings are cast tight against undisturbed soils. If a combination of the passive pressure and friction is used, the friction value should be reduced by one-third. FOUNDATION EXCAVATION OBSERVATIONS All foundation excavations should be observed by the Geotechaical Consultant prior to placing concrctc to determine if the foundation tccommendations presented herein are complied with. All footing excavations should be excvated neat, level and square. All loose or unsuitable material should be retuoved prior to the placement of concrete. ON-GRADE SLABS INTERIOR FLOOR SLABS: The mioisnv.nt floor slab thickness should he four inches. The floor slab should be reinforced with at least No. 3 bars placed at 18 inches on center each way. Slab reinforcing should be positioned on chairs at mid-height in the floor slab. MOISTURE PROTECTION FOR INTERIOR SLABS: Where the concrete oa-gradc floor slabs will support moisture-sensitive floor covering, it should be underlain by a moisture barrier. We recommend that the minimum configuration of the subsiab moisture barrier consist of a four-inch-thick blanket of coarse, clean sand. The moisture battier material should have 100 percent material passing the ¼ -inch sieve and less than ten percent and five percent passing the No. 100 and No. 200 sieves, respectively. A visqueen vapor barrier should be placed in the center of the moisture protection blanket. FROM :CHRISTIAN WHEELER ENGINEERING FAX NO. :8584969758 Jun. 03 2002 07:57AM P4/4 201.&15.8 June 3, 2002 Page 3 EXTERIOR CONCRETE FLATWORK Exterior slabs should haven miriinum thickness of four inches. Reinforcement arid control joints should be constructed in exterior concrete flntwork to reduce the potential for cracking and movement. Spacing of control joints should be in accordance with the American Concrete Institute spccffications. When exterior slabs abut perimeter foundations they should be doweled into the footings The rough grading of other areas of the project is in progress. A formal report presenting a summary of our observations and tests will be prepared and submitted upon the completion of the rough grading work. If you should have any questions about the services provided on the project by our firms please do not hesitate to contact our office- This opportunity to bc of professional service on your project is sincerely appreciated. Respectfully submittcci, CHRISTIAN WHEELER ENGINEERING Charles Ii Christiu, R.G.E. 00215 CHC/i)H/dh cc: (2) Submitted (4) Lusaxdi Con.ctruction s FROM :CHRIST IAN. .tJkEELER ENGINEERING FAX NO. :0584969759 May. 29 2002 11:58PM P2/4 w CHRJSTiAN WHEELER. E N C I N E £ K. I N G May 29, 2002 Caritas Development Company CWE 201,615.7 500 Avcnida Encinas, Suite 100 Carlsbad, California 92008 Attetion John White SUBJECT: VERIFICATION OF GEOTECHNICAL SERVICES, NORTH POINTE WEST BUILDINGS 3 & 4, CORTE DE LA PINA1 CARLSBAD, CALIFORNIA. C.T. 01-08 Reference: "Update Geotechnical Report, North Pointe West, Corte de In Puna and El Cawino Real, Carlsbad, Cal forum," by Christian Wheeler Engineering, dated September, 24, 2001 Ladies/Gentlemen, This letter is written to confirm that Christian Wheeler Engineering has provided gcotethnical observation and tcsting servicce on a continuous basis during the mass grading performed on Building Pad Numbers 2,3, and 4 at the subject site. CONCLUSIONS Based upon our tests and observations, it is our opinion that the earthwork was performed substantially in compliance with the recommendations presented in the above referenced report, the City of Carlsbad grading requirements, red the Uniform Building Code. It is out further opinion that the building pads are suitable for the support of the proposed buildings. Our recommendations for the minimum design of foundations are presented in the following paragraphs. FOUNDATIONS GENERAL2 It is our opinion that the proposed tilt-tip structures may be supported by conventional continuous and spread footings. Expansion index tests performed in our laboratory indicate that the foundation soils for the proposed buildings have a modczatc potential for expansion; the recommendations presented herein reflect this condition. 4925 Mercury Street + San Diego, CA 92111 + 858-496-9760 + FAX 858-496-97R c-. FROM :CHRISTIAN WHEELER ENGINEERING FAX NO. :8584969758 May. 29 2002 11:59AM P3/4 CONVENTIONAL FOUNDATIONS: Conventional continuous and spread footings supporting the proposed strtictuit hnuld bc founded at least 18 inches below the lowest adjacent finished grade. Continuous footings thould have ,,% minimum width of 12 inches. Horizontal dimengion.4 of isntatc.d footings should be at least 24 inches by 24 inches. EA.RXNG CAPACITY: Conventional footings with the above minimum dimensions may he designed for an allowable soil bearing pressure of 2,500 pounds per square foot. This value may be inctcased by one-third for combination of temporary loads such as those due to wind or seismic loads. POOTING REINFORCING; Reinforcement requirements for foundations should be provided by the project stmcturat engineer. However, based on the existing soil conditions, we recommend that the minimum reinforcing for continuous footings consist of at least two No. 5 bats positioned three inches above the bottom of the footing and two No. S bars positioned two inches below the top of the footing. LATERAL LOAD RESISTANCE: Lateral loads against foundations may be resisted by friction between the bottom of the footing and the supporting soil, and by the passive pressure against the footing. The coefficient of friction between concrete and soil may be considered to be 0.35. The passive resittance may be considered to be equal to an equivalent fluid weight of 350 pounds per cubic foot. This assumes the footings are cast tight against undisturbed soils. If a combination of the passive pressure and friction is mcd, the friction value should be reduced by one-third. FOUNDATION EXCAVATION OBSERVATION: All foundation excavations should be observed by the Geotechakal Consultant prior to placing concrete to determine if the foundation recommendations presented herein are complied with. All footing excavations should be excavated neat, level and square. All loose or unsuitable material shuuld be removed prior to the placement of concrete. ON-GRADE SLABS INTERIOR FLOOR SLABS; The minimum floor slab thickness should be four inches. The floor slab - should be reinforced with at least No. 3 bars placed at 18 inches on center each way. Slab reinforcing should be positioned On chafta at mid-height in the Boor slab. MOISTURE PROTECTION FOR INTERIOR SLABS; Where the concrete on-grade floor slabs will support moisture-enaitivc floor covering, it should be underlain by a moisture barrier. We recommend that the minimum configuration of the subalab moisture barrier consist of a four-inch-thick blanket of coarse, clean sand. The moisture bather material should have 100 percent material passing the 1/i -inch sieve and 1ess than ten percent and five percent passing the No. 100 and No. 200 sieves, respectively. A visqucen vapor barrier should be placed in the center of the moisture protection blanket, FROM :CHRISTIAN WHEELER ENGINEERING FAX NO. :0594969759 May. 29 2992 11:59AM P4/4 EXTERIOR CONCRETE FLATWORK Exterior slabs should haven minimum thickness of four Inches. Reinforcement and control joints should be constructed in exterior concrete f]twds to reduce the potential for craddng and movement, Spacing of control joints should be in accordance with the American Concrete Institute specifications. When exterior slabs abut perimeter foundations they should be dowcld into the footings. The rough gdlng of other areas of the project is in progress. A formal report presenting a summary of our observations and tests will be prepared and, submitted upon the completion of the rough grading work If you should have any questions about the sefvicee, provided on the project by our fm=, please di, not hesitate to - contact our office. This opportunity to be of professional sctvicc on your project is sincerely appreciated. Repcctfuity submitted, CHRISTIAN 1-LEELER ENGINEERING Charles H. Chrietkn, X.G.E. 002i CflC/tf/dh cc: (2) Submitted (4) Lusardi Concttuctlon Co 0 NO. 6E215 LU ExP.93OO5 I J*1