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HomeMy WebLinkAbout; Asap Oil Change; Soils Report; 1987-11-17ENGINEERING DEPT. LIBRARY City of Carlsbad 2075 Las Palmas Drive CarMad, CA92009-4959 SITE PREPARATION AND FOUNDATION RECOmENDATIONS ASAP OIL CHANGE COLLEGE AVENUE OCEANSIDE, CALIFORNIA c\-~y OF OCEANSlDE BMLDING DEPARTMENT PREPARED FOR: Madfson Square Partnership 4223/A Ponderosa Avenue San Diego. Callfornfa 92123 PREPARED BY: SOUthern California Soil 1 Testing, Inc. Post,Office Box 20627 6280 Riverdale Street San Diego, California 92120 November 17, 1987 Madison Square Partnership 4223/A Ponderosa Avenue San Diego, California 92123 SCSBT 8721183 Report No. 2 SUBJECT: Earth Retaining Structures Design Recommendations, ASAP Oil Change, College Avenue, Oceanside, California. Gentlemen: In accordance with a request from Mr. Randy Cramer we are providing herein earth retaining structuae design recommendations for the subject project. EARTH RETAINING WALLS PASSIVE PRESSURE: The passive pressure for the prevailing soil conditions may be considered to be 450 pounds per square foot per foot of depth up to a maximum of 1500 psf. This pressure may be increased one-third for seismic loading. The coefficient of friction for concrete to soil may be assumed to be 0.3 for the resistance to lateral movement. When combining frictional and passive resistance, the latter should be reduced by one-third. ACTIVE PRESSURE: The active soil pressure for the design of earth retaining structures with level backfills may be assumed to be equivalent to the pressure of a fluid weighing 33 pcf and 50 pcf for unrestrained and restrained conditions. These pressures do not consider any other surcharge. If any are anticipated, this office should be contacted for the necessary SCIUTHERN CAL~IFOANIA SOIL AND TESTING. INC SCSAT 8721183 - - - - - - .~ - - SITE AND SOIL DESCRIPTION October 26, 1987 Page 2 The subject site is located at the north western section of the existing Home Depot Shopping Center. The site is bounded to the west by College Avenue to the north by Stop-n-Go and to the east and south by paved parking. The subject site was graded in 1986. Grading consisted of fills up to 12 feet deep. The site is underlain by nondetrimentally expansive silty sands. CONCLUSIDRS AlID RECoWENDATIONS GENERAL No geotechnical conditions were encountered which will preclude site development as presently proposed. In general, the site is underlain by fill deposits consisting of nondetrimentally expansive silty sands with excellent foundation support characteristics. However, it is anticipated that the upper half foot to a foot of this material may be disturbed due to weathering. This condition will require site preparation or increased foundation and concrete slab-on-grade consideration. Recolnaendations for both alternatives are provided herein. GRADING SITE PREPARATION: If conventional slabs-on-grade are desired, site preparation should consist of scarifying the upper 12 inches of soil in areas to receive settlement sensitive improvements (fills and exterior slabs included). This material should be moisture conditioned and recompacted to at least 90 percent as determined in accordance with ASTM D1557-78 Method A or C. DRAINAGE: The site should be graded and maintained such that surface drainage is directed away from the structures and the top of slopes into swales or other controlled drainage devices. - SCSAT 8721183 October 26, 1987 Page 3 - EARTHWORK: All earthwork and grading contemplated for site preparation should be accomplished in accordance with the attached Recammnded Grading Specifications and Special Provisions. All special site preparation recotmnendatfons presented in the sections above will supersede those in the standard Recommended Grading Specifications. All embankments, structural fill and fill should be compacted to at least 90$ relative compaction at or slightly over optimum moisture content. Utility trench backfill within 5 feet of the proposed structures and beneath asphalt pavements should be compacted to mini~m of 90% of its maximum dry density. The maximum dry density of each soil type should be determined in accordance with A.S.T.M. Test Method D-1557-78. Method A or C. FOUNDATIONS - - .~ GENERAL: Shallow foundations may be utflfred for the support of the proposed structure. The footings should have a mfnfmum depth of 12 inches below lowest adjacent finish grade. If the existing surface soils are not scarified, mfni~m foundation depth should be 18 inches. Amfnfmum width of 12 inches and 18 inches is recwnded for continuous and isolated footings respectively. A bearing capacity of 2000 psf amy be assumed for said footings. This bearing capacity may be increased by one-third when considering wind and/or seismic forces. A minimum setback from the face of slopes to the footing equal to a horizontal distance of seven feet should be observed. For retaining walls, this distance should be increased to ten feet. REINFORCMERT: Roth exterior and interior continuous footings should be reinforced with one 14 bars positioned near the bottom of the footing and one 14 bars positioned near the top of the footing. This reinforcement is based on soil characteristics and is not intended to be in lieu of reinforcement necessary to satisfy structural considerations. CONCRETE SLABS-ON-GRADE: Concrete slabs-on-grade should have a mfnfaum. actual thickness of four inches and be underlain by a two-inch blanket of clean poorly graded coarse sand or crushed rock. The slab should be reinforced with No. 3 reinforcing bars placed at 36 inches on center each way. A 6*x6*-W1.4xW1.4 may be used in lieu of the rebars. It is imperative .- - - SCSAT 8721183 October 26, 1987 Page 4 that the mesh be placed in the middle of the slab in order to be effective. If the surface soils are not scarified, minfmum slab thickness and reinforcement should be five inches and No. 3 rebars placed at 18 inches on center each way. The rebars should be extended at least six inches into the footing. Where moisture sensitive floor coverings are planned, a visqueen barrier should be placed on top of the sand layer. A two-inch-thick layer of clean sand should be placed over the vfsqueen to allow for proper concrete curing. LIWITATIONS The reccimnendations and opinions expressed in this report reflect our best estimate of the project requirements based on an evaluation of the subsurface soil conditions encountered at the subsurface exploration locations and the assumption that the soil conditions do not deviate appreciably from those encountered. It should be recognfzed that the performance of the foundations and/or cut and fill slopes may be influenced by undisclosed or unforeseen variations in the soil conditions that may occur in the intermediate and unexplored areas. Any unususal conditions not covered in this report that may be encountered during construction should be brought to the attention of the soils engineer so that he may make modificatfons if necessary. In addition, this office should be advised of any changes in the project scope or proposed site grading so that it may be determined if the recammndations contained herein are appropriate. This should be verified in writing or modified by a written addendum. If you have any questions regarding this report please contact our office. Respectfully submitted, TESTING,, INC. Daniel B. Adler, R.C.E. Yb6037 DBA:nm cc: (4) Submitted (1) SCS6T. Escondfdo - - - - - - .- - ASAP OIL CHANGE, COLLEGE AVENUE, OCEANSIDE RECOMIENDED GRADING SPECIFICATIONS - GENERAL PROVISIONS GENERAL INTENT The intent of these specifications is to establish procedures for clearing, compacting natural ground, preparing areas to be filled, and placing and compacting fill soils to the lines and grades shown on the accepted plans. The recommendations contained in the preliminary geotechnfcal investigation report and/or the attached Special Provisions are a part of the Recmnded Grading Specifications and shall supersede the provisions contained hereinafter in the case of conflict. These specifications shall only be used in conjunction with the geotechnfcal report for which they are a part. No deviation from these specifications will be allowed, except where specified in the geotechnfcal soil report or in other written communication signed by the Soil Engineer. OBSERVATION AND TESTIffi Southern California Soil and Testing, Inc., shall be retained as the Soil Engineer to observe and test the earthwork in accordance with these specifications. It will be necessary that the Soil Engineer or his representative provide adequate observation so that he may provide an opinion that the work was or was not accomplished as specified. It shall be the responsfbflity of the contractor to assist the soil engineer and to keep him appraised of work schedules, changes and new information and data so that he may provide these opinions. In the event that any unusual conditions not covered by the special provisions or preliminary soil report are encountered during the grading operations, the Soil Engineer shall be contacted for further recomnendatfons. If, in the opinion of the Soil Engineer. substandard conditions are encountered, such as; questionable or unsuitable soil, unacceptable (~-8187) - - - SCSAT 8721183 October 26, 1987 Appendix, page 2 moisture content, inadequate compaction, adverse weather, etc., construction should be stopped until the conditions are remedied or corrected or he shall recommend rejection of this work. Test methods used to determine the degree of compaction should be performed in accordance with the following Pmerfcan Society for Testing and Materials test methods: Maxfnmm Density 6 Optimum Moisture Content - A.S.T.M. D-1557-78. Density of Soil In-Place - A.S.T.M. D-1556-64 or A.S.T.H. D-2922. All densities shall be expressed in terms of Relative Compaction as determined by the foregoing A.S.T.M. testing procedures. PREPARATION OF AREAS TO RECEIVE FILL All vegetation, brush and debris derived from clearing operations shall be removed, and legally disposed of. All areas disturbed by site grading should be left in a neat and finished appearance, free from unsightly debris. After clearing or benching, the natural ground in areas to be filled shall be scarified to a depth of 6 inches, brought to the proper moisture content, compacted and tested for the minimum degree of compaction in the Special Provisions or the recolaoendatfon contained in the preliminary geotechnfcal investigation report. All loose soils in excess of 6 inches thick should be removed to firm natural ground which is defined as natural soils which possesses an in-situ density of at least 90% of its maximum dry density. When the slope of the natural ground receiving fill exceeds 20% (5 horizontal units to 1 vertical unit), the original ground shall be stepped (R-8/871 -. - - - - - ,~- SCSELT 8721183 October 26. 1987 Appendix, page 3 or benched. Benches shall be cut to a firm competent soil condition. The lower bench shall be at least 10 feet wide or 1 l/2 times the the equipment width which ever is greater and shall be sloped back into the hillside at a gradient of not less than two (21 percent. All other benches should be at least 6 feet wide. The horizontal portion of each bench shall be compacted prior to receiving fill as specified herein for compacted natural ground. Ground slopes flatter than 209: shall be benched when considered necessary by the Soil Engineer. Any abandoned buried structures encountered during grading operations must be totally removed. All underground utilities to be abandoned beneath any proposed structure should be removed from within 10 feet of the structure and properly capped off. The resulting depressions from the above described procedures should be backfilled with acceptable soil that is compacted to the requirements of the Soil Engineer. This includes, but is not limited to, septic tanks, fuel tanks, sewer lines or leach lines, storm drains and water lines. Any buried structures or utilities not to be abandoned should be brought to the attention of the Soil Engineer so that he may determine if any special reconmmndatfon will be necessary. All water wells which will be abandoned should be backfilled and capped in accordance to the requirements set forth by the Soil Engineer. The top of the cap should be at least 4 feet below finish grade or 3 feet below the bottom of footing whichever is greater. The type of cap will depend on the diameter of the well and should be determined by the Soil Engineer and/or a qualified Structural Engineer. FILL MATERIAL Materials to be placed in the fill shall be approved by the Soil Engineer and shall be free of vegetable matter and other deleterious substances. Granular soil shall contain sufficient fine material to fill the voids. (R-8/87) - - .-. .- - - - -. - - - SCS&T 8721183 October 26, 1987 Appendix, page 4 The definition and disposition of oversized rocks, expansive and/or detrimental soils are covered in the geotechnical report or Special Provisions. Expansive soils, soils of poor gradation, or soils with low strength characteristics may be thoroughly mixed with other soils to provide satisfactory fill material, but only with the explicit consent of the soil engineer. Any import material shall be approved by the Soil Engineer before being brought to the site. PLACING AND COMPACTION OF FILL Approved fill material shall be placed in areas prepared to receive fill in layers not to exceed 6 inches in compacted thickness. Each layer shall have a uniform moisture content in the range that will allow the compaction effort to be efficiently applied to achieve the specified degree of compaction. Each layer shall be uniformly compacted to a mfninum specified degree of compaction with equipment of adequate size to economically compact the layer. Compaction equipment should either be specifically designed for soil compaction or of proven relfability. The minimum degree of compaction to be achieved is specified in either the Special Provisions or the recommendations contained in the preliminary geotechnfcal investigation report. When the structural fill material includes rocks, no rocks will be allowed to nest and all voids must be carefully filled wfth soil such that the minimum degree of compaction recommended in the Special Provisions is achieved. The maximum size and spacing of rock permitted in structural fills and in non-structural fills is discussed in the geotechnical report, when applicable. Field observation and compaction tests to estimate the degree of compaction of the fill will be taken by the Soil Engineer or his representative. The location and frequency of the tests shall be at the Soil Engineer's (R-8/87) - - - .- - - - - SCS6T 8721183 October 26, 1987 Appendix, page 5 discretion. When the compaction test indicates that a particular layer is less than the required degree of compaction, the layer shall be reworked to the satisfaction of the Soil Engineer and until the desired relative compaction has been obtained. Fill slopes shall be compacted by means of sheepsfoot rollers or other suitable equipment. Compaction by sheepsfoot rollers shall be at vertical intervals of not greater than four feet. ‘In addition, fill slopes at ratios of two horizontal to one vertical or flatter, should be trackrolled. Steeper fill slopes shall be over-built and cut-back to finish contours after the slope has been constructed. Slope compaction operations shall result in all fill material six or more inches inward from the finished face of the slope having a relative compaction of at least 90% of maximum dry density or that specified in the Special Provisions section of this specification. The compaction operation on the slopes shall be continued until the Soil Engineer is of the opinion that the slopes will be stable in regards to surficial stability. Slope tests will be made by the Soils Engineer during construction of the slopes to determine if the required compaction is being achieved. Where failing tests occur or other field problems arise, the Contractor will be notified that day of such conditions by written camunication from the Soil Engineer or his representative in the form of a daily field report. If the method of achieving the required slope compaction selected by the Contractor fails to produce the necessary results, the Contractor shall rework or rebuild such slopes until the required degree of compaction is obtained. at no cost to the Owner or Soils Engineer. ( R-8/87 ) - - - - SCS6T 8721183 October 26, 1987 Appendix, page 6 CUT SLOPES The Engineering Geologist shall inspect cut slopes excavated in rock or lithiffed formational material during the grading operations at intervals determined at his discretion. If any conditions not anticipated in the preliminary report such as perched water, seepage, lentfcular or confined strata of a potentially adverse nature, unfavorably inclined bedding, joints or fault planes are encountered during grading, these conditions shall be analyzed by the Engineering Geologist and Soil Engineer to determine if mitigating measures are necessary. Unless otherwise specified in the geotechnfcal report, no cut slopes shall be excavated higher or steeper than that allowed by the ordinances of the controlling governmental agency. ENGINEERING OBSERVATION Field observation by the Soil Engineer or his representative shall be made during the filling and compacting operations so that he can express his opinion regarding the conformance of the grading with acceptable standards of practice. The presence of the Soil Engineer or his representative or the observation and testing shall not release the Grading Contractor from his duty to compact all fill material to the specified degree of compaction. SEASON LINITS Fill shall not be placed during unfavorable weather conditions. When work is interrupted by heavy rain, filling operations shall not be resumed until the proper moisture content and density of the fill materials can be achieved. Damaged site conditions resulting from weather or acts of God shall be repaired before acceptance of work. (R-81871 - -. SCS&T 8721183 October 26, 1987 Appendix, page 7 RECOMENDED GRADING SPECIFICATIONS - SPECIAL PROVISIONS - RELATIVE CMPACTION: The minimum degree of compaction to be obtained in compacting natural ground, in the compacted fill, and in the compacted backfill shall be at least 90 percent. For street and parking lot subgrade, the upper six inches should be compacted to at least 95% relative compaction. - - - - - ..~ ,- - - -. EXPANSIVE SOILS: Detrimentally expansive soil is defined as clayey soil which has an expansion index of 50 or greater when tested in accordance with the Uniform Building Code Standard 29-C. OVERSIZED MATERIAL: Oversized fill material is generally defined herein as rocks or lumps of soil over 6 inches in diameter. Oversize materials should not be placed in fill unless recommendations of placement of such material is provided by the soils engineer. At least 40 percent of the fill soils shall pass through a No. 4 U.S. Standard Sieve. TRANSITION LOTS: Where transitions between cut and fill occur within the proposed building pad, the cut portion should be undercut a minimum of one foot below the base of the proposed footings and recompacted as structural backfill. In certain cases that would be addressed in the geotechnfcal report, special footing reinforcement or a combination of special footing reinforcement and undercutting may be required. (~-8187) , SCS&T 8721183 November 17, 1987 Page 2 increase in soil pressure. This value assumes a drained backfill condition. Waterproofing and drainage details should be provided by the project architect. BACKFILL: All backfill soils should be compacted to at least 90% relative compaction. Expansive or clayey soils should not be used for backfill material. The wall should not be backfilled until the masonry has reached an adequate strength. FACTOR OF SAFETY: The above values, with the exception of the allowable soil friction coefficient, do not include a factor of safety. Appropriate factors of safety should be incorporated into the design to prevent the walls from overturning and sliding. If you should have any questions after reviewing this report, please do not hesitate to contact this office. This opportunity to be of professional service is sincerely appreciated. Respectfully submitted, Daniel B. Aher, 6C.E. #36037 DBA:nm CC: (3) Submitted (3) BSHA, Attention, Mr. Randy Cramer (1) SCS&T, Escondido October 26, 1987 Madison Square Partnership 4223/A Ponderosa Avenue San Diego. California 92123 SCSAT 8721183 Report No. 1 -. - - .- SUBJECT: Site Preparation and Foundation Recoimaendations, ASAP Oil Change, College Avenue, Oceanside, California. REFERENCE: "Report of Field Observation and Relative Compaction, Rome Depot Oceanside"; Southern California Soil and Testing, Inc.; June 9, 1986. Gentlemen: In accordance with your request, we are providing herein site and foundation recommendations for the subject project. PROJECT DESCRIPTION It is our understanding that the proposed development will be developed to receive a one story cercfhl structure of wood-frame construction and associated paved parking. Shallow foundations and conventional slab-on-grade floor systems are anticipated. Grading will be very minor and for drainage purposes. SOUTHERN CALIFORNIA 501L AND TESTINO. INC.