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1997-4971 G Street Address 3L&~ Category / ZS;)34CJ Serial # Lf~1-r.~ Name / Description Plan ck. # Year recdescv I I I I I I I I I I I I ! I I I I I I I REPORT OF ROUGH GRADING PROPOSED BARN HODGES RESIDENCE 2896 LONE JACK ROAD ENCINITAS, CALIFORNIA JOB NO. 90-57 APRIL 4, 1997 -#- 177 G 7 WESTERN SOIL AND FOUNDATION ENGINEERING¡ INC ì - I I I I I I I I I I I I I I I I I I I WESTERN SOIL AND FOUNDATION ENGINEERING, INC. PHONE: (619) 746-3553 FAX: (619)746-4912 423 HALE AVENUE ESCONDIDO. CALIFORNIA 92029 April 4, 1997 Mr. Phil Hodges 2896 Lone Jack Road Encinitas, California 92024 Project: Our Job No. 90-57 Proposed Barn Hodges Residence 2896 Lone Jack Road Encinitas, California Subject: Report of Rough Grading Dear Mr. Hodges: In accordance with your request, we have provided testing and observation services during the grading on the above referenced project. Our services were performed during the period of March 12, 1997 through March 24, 1997, the date of our last observation and testing of compacted soils for this portion of the project. In summary, our scope of services during this period of time included the following: . Observing the grading operation, including the removal of existing soil materials, . Performing in-place density tests in fill material imported to and compacted at the site, I I I I I I I I I I I I I I I I I I I Hodges Residence April 4, 1997 Our Job No. 90-57 Page 2 . Performing laboratory tests on samples of the imported soils used for this project, . Preparing this report of grading observation. The scope of our observations and testing services did not include the responsibility for surveying; the locations and elevations of the tests were determined from stakes and hubs set by others. The locations of the field density tests are presented on the attached Site Plan. The site plan was provided by Logan Engineering. OBSERVATIONS AND TESTING The recent earthwork performed on the proposed barn pad consisted of the following items: . Remove the existing soil within the fill slope keyway to a depth of 10 feet below the toe of the slope, . Removal of the existing soil to a depth of 4 feet below finish grade of the barn pad, and WESTERN SOIL AND FOUNDATION ENGINEERING, INC. I I I I I I I I I I I I I I I I I I I Hodges Residence April 4, 1997 Our Job No. 90-57 Page 3 . Placement of compacted imported fill to grade the site and to provide support for the proposed foundations and floor slabs. Maximum cuts and fills on the order of 4 feet and 7 feet, respectively were required to obtain the design elevations. To allow for the placement of at least 4 feet of fill beneath the proposed structure, overexcavation of the native materials was required on the cut portion of the lot. After removal of the upper 10 feet the exposed soils in the keyway were recompacted. After recompaction the import soils were placed in loose lifts and compacted using a D-8 track dozer and a large rubber-tire loader. Water was added using a water hose. To evaluate the degree of compaction of the fill soils, field density tests were performed in accordance with ASTM DI556-90, the sand cone method or ASTM D2922-81, the nuclear gauge method. The field density tests taken during grading were spaced to provide optimum coverage. The reported relative compaction is defined as the ratio of the field dry density to the laboratory maximum dry density. The laboratory compaction tests used in calculating the relative compaction of the field density tests were performed on representative samples of imported soil material in accordance with ASTM DI557-91. Both field density and laboratory compaction test methods and results are presented on the following pages. This report includes fill field density test numbers 1 through 8, performed between March 19 and 24, 1997. WESTERN SOIL AND FOUNDATION ENGINEERING, INC L- - I I I I I I I I I I I I I I I I I I I Hodges Residence April 4, 1997 Our Job No. 90-57 Page 4 The approximate area of fill tested, and the approximate location of the field density tests are shown on the Site Plan located in this report. No observation or testing was performed beyond these limits as depicted in this report. RECOMMENDATIONS Drainage Control: Adequate drainage must be provided and maintained to prevent water from ponding around or under the foundations. Water shall not be allowed to flow in an uncontrolled manner over the top or face of any slope. All brow ditches, drainage swales and other drain systems, as shown on the Project Plans, shall be constructed in a timely manner. Periodic maintenance must be performed on all drainage systems, both surface and subsurface, to insure that they operate properly during the design life of the project. Erosion control and drainage devices shall be installed in compliance with the requirements of the controlling agencies. WESTERN SOIL AND FOUNDATION ENGINEERING, INC. I I I I I I I I I I I I I I I I I I I Hodges Residence April 4, 1997 Our Job No. 90-57 Page 5 Retaining Wall Drains: To limit the entrapment of water in the backfill behind the wall, backdrains or other drainage measures should be installed. Drainage should consist of vertical gravel drains about 12 inches wide connected to a 4-inch-diameter perforated pipe. The pipe shall be ABS schedule 40 (ASTM-D1527) or SDR 23.5 (ASTM-D2751) or approved equal. The perforated pipe should be placed with the perforations down and should be surrounded by at least I foot of filter gravel or uniformly graded gravel or Caltrans Class 2 permeable material wrapped in geosynthetic filter fabric, such as Mirafi 140NS or approved equivalent. Care should be taken to select a filter fabric compatible with the backfill materials. The drain pipe should be located near the base of the wall and should discharge into a storm drain or onto a surface draining away from the structure. As an alternative to the vertical gravel drains, a drainage geocomposite such as Miradrain may be used with a 4 inch-diameter perforated pipe collector drain. Walls below grade should be waterproofed or at least damp proofed depending on the degree of moisture protection desired. Slopes: Permanent constructed slopes shall be finish graded to an inclination no steeper than specified within the soil reports and approved plans for this project. Slopes shall be planted as soon as possible after grading. Slope erosion including sloughing, rilling, and slumping of surface soils may be anticipated if the slopes are left unplanted for a long period of time, especially during rainy seasons. Over watering of the slopes is not recommended. Concrete swales and earth berms or back-gradients are recommended at the top of permanent slopes to prevent surface water runoff from overtopping the slopes. Erosion control and drainage devices shall be installed in compliance with the requirements of the controlling agencies. WESTERN SOIL AND FOUNDATION ENGINEERING, INC. I I I I I I I I I I I I I I I I I I I Hodges Residence April 4, 1997 Our Job No. 90-57 Page 6 Foundations: Representative samples of the imported soil, used for grading the building pad were returned to our laboratory to determine their expansive potential and allowable bearing value. Test results are presented on page 12 of this report. The results of our test and engineering analysis indicate that these soils have a low expansion potential and 2 of the 3 samples meets the criteria presented in our letter of Limited Geotechnical Evaluation dated February 26, 1997. Therefore, special foundations to reduce the detrimental effects of expansive soil are not necessary. The proposed foundation shall be entirely established on at least 4 feet of compacted fill. Foundations may be designed in accordance with the dimensions and allowable soil bearing values presented in the table below. Minimum Minimum Allowable Footing Depth Width Soil Bearing Tvpe (Inches) (Inches) Value (pst) Continuous 24 15 1000 Pad 24 24 1000 The depth shall be measured from lowest adjacent subgrade. The allowable soil bearing values presented above may be increased by one-third for wind or seismic loading. All continuous footings shall contain at least two #5 reinforcing bars, one top and one bottom, to provide structural continuity and to permit spanning of local irregularities. The foundation dimensions and reinforcing presented above are minimum recommendations only. These may be increased by the Structural Engineer, as required. WESTERN SOIL AND FOUNDATION ENGINEERING, INC. I I I I I I I I I I I I I I I I 'I I I Hodges Residence April 4, 1997 Our Job No. 90-57 Page 7 If footings are proposed adjacent to slope areas, we recommend that the footings be deepened to provide a minimum horizontal distance of 10 feet from the outer edge of the footings to the adjacent slope face. Concrete Slabs-On-Grade: To provide more uniform support, the concrete slab-on-grade shall be underlain by at least 4 feet of non-expansive compacted fill as recommended in our referenced report. No cut/fill transitions should be allowed. To provide protection against vapor or water transmission through the building floor slabs, we recommend that the slabs-on-grade be underlain by a 4-inch layer of Caltrans Class 2 permeable material or gravel. A suggested gradation for the gravel layer is as follows: Percent Passing Sieve Size 3/4" 90-100 No.4 0-10 No. 100 0-3 WESTERN SOIL AND FOUNDATION ENGINEERING, INC I I I I I I I I I I I I I I I I I I I Hodges Residence April 4, 1997 Our Job No. 90-57 Page 8 If vinyl or other moisture-sensitive floor covering is planned, or if materials that are damaged by moisture are to be stored in the barn, we recommend that the 4-inch-thick gravel layer be overlain by a 10-mil-thick impermeable plastic membrane to provide additional protection against water vapor transmission through the slab. The vapor barrier should be installed in accordance with the manufacturer's instructions. We recommend that at least a 2- foot lap be provided at the membrane edges or that the edges be sealed. To protect the membrane during later concrete work, to facilitate curing of the concrete, and to reduce slab curling, a 2-inch-thick layer of clean-sand shall be placed over the membrane. If sand bedding is used, care should be taken during concrete placement to prevent displacement of the sand. A low-slump concrete (4-inch maximum slump) should be used to further minimize possible curling of the slabs. The concrete slabs should be allowed to cure properly before placing vinyl or other moisture-sensitive floor covering. As an alternative to crushed rock a 4-inch layer of clean sand with a plastic membrane (visqueen) placed at the mid-point may be used. Slab reinforcing shall be provided in accordance with the anticipated use and loadings on the slab and as recommended by the Structural Engineer. As a minimum, slabs-on-grade shall be 4 inches in thickness and shall contain No.3 reinforcing bars placed at mid-height in the slab at 24 inches on center both ways. To help control random cracking, contraction (control) joints should be installed in the slab-on-grade at a spacing not to exceed 13 feet. Contraction joints should extend into the slab a minimum depth equal to one-fourth the slab thickness. WESTERN SOIL AND FOUNDATION ENGINEERING, INC. I I I I I I I I I I I I I I I I I I I Hodges Residence April 4, 1997 Our Job No. 90-57 Page 9 Earthwork: It is our understanding that the rough grading for the Hodges barn building pad, is now complete. Some additional earthwork may be performed for the installation of utilities, retaining walls and finish grading. We should be notified prior to the commencement of any proposed earthwork. Additional fill or backfill that is placed on the building pad should be tested for proper compaction. CONCLUSIONS Based on our observations and test results, the sub grade preparation and placement of compacted fill were performed in general compliance with the recommendations presented in our letter of Limited Geotechnical Evaluation, dated February 26, 1997. The results of our observations, field density and laboratory tests indicate that the fill, at the locations and elevations tested by us, was compacted to no less than 90% of its maximum dry density (ASTM DI557-91). WESTERN SOIL AND FOUNDATION ENGINEERING, INC I I I I I I I I I I I I I I I I I I I Hodges Residence April 4, 1997 Our Job No. 90-57 Page 10 In providing professional geotechnical observations and testing services associated with the development of the project, we have employed accepted engineering and testing procedures and made every reasonable effort to ascertain that the soil-related work was carried out in general compliance with the recommendations and project specifications. Although our observation did not reveal obvious deficiencies, we do not guarantee the contractor's work, nor do the services performed by our firm relieve the contractor of responsibility in the event of subsequently discovered defects in the contractor's work. Respectfully submitted, WESTERN SOIL AND FOUNDATION ENGINEERING, INC. t::¡ d! A- Vincent W. Gaby, CEG 1755, Expires 7/31/97 Engineering Geologist ~ ~~-~~ Susana Kemmerrer, RGE 2287, Expires 6/30/97 Geotechnical Engineer President K2 Engineering Inc. Attachments: Test Results Site Plan Distribution: (4) Addressee VWG/SK:dg WESTERN SOIL AND FOUNDATION ENGINEERING, INC. I I I I I I I I I I I I I I I I I I I Hodges Residence April 4, 1997 Our Job No. 90-57 Page 11 Fill Laboratory Compaction Test Results Soil Description Maximum Dry Density (pct) Optimum Moisture Content (%) Light Brown, Silty, Fine Grained Sand (1) 118.3 12.5 Brown, Silty, Fine Grained Sand (2) 123.5 10.5 Pale Yellow, Fine to Medium Grained Sand 115.0 14.0 Light Brown, Silty Sand 121.0 11.5 (1) (2) Soil not imported, did not meet specification. Soil not imported, material was sent to another site. Fill Field Density Test Results Test Re- Date Test Test Location 1997 No. of No. of Test 3-19 1 See Site Plan Ht of Fill & Elev. (Feet) +3.0 169.0 Field Field Maximum Moisture Dry Dry Relative Content Density Density Compaction (%) ( pct) (pct) (%) 17.1 112.0 115.0 97.4 2 See Site Plan +5.0 171.0 18.3 109.3 115.0 95.0 WESTERN SOIL AND FOUNDATION ENGINEERING¡ INC. I I I I I I I 3-19 I 3-20 I I I I 3-24 I I I I I I I Test Date 1997 Hodges Residence April 4, 1997 Fill Field Density Test Results Test No. Re- Test Location of No. of Test Ht of Fill & Elev. (F eet) 3 See Site Plan +7.0 173.0 4 See Site Plan +9.0 175.0 5 See Site Plan +11.0 177.0 6 See Site Plan +13.0 179.0 7 See Site Plan +15.0 181.0 8 See Site Plan F.G. 183.0 Our Job No. 90-57 Page 12 Field Field Maximum Moisture Dry Dry Relative Content Density Density Compaction (%) (pet) (pet) (%) 16.3 110.7 115.0 96.3 16.8 112.1 16.1 110.3 18.3 103.9 18.6 108.5 8.1 114.5 * Test taken by the nuclear gauge method. WESTERN SOIL AND FOUNDATION ENGINEERING, INC. 115.0 97.4 115.0 95.9 115.0 90.3 115.0 94.3 121.0 94.6* I I I I I I I I I I I I I I I I I I I Hodges Residence April 4, 1997 Our Job No. 90-57 Page 13 DIRECT SHEAR Sample Description Apparent Cohesion (pst) Angle of Internal Friction (degrees) Light Brown, Silty, Fine Grained Sand 235 29 Brown, Silty, Fine Grained Sand 25 33 Pale Yellow, Fine to Medium Grained Sand 50 34 EXP ANSION INDEX Initial Final Sample Expansion Moisture Moisture Expansion Location Index (%) (%) Potential Barn Import Soil 13 10.5 19.0 Very Low WESTERN SOIL AND FOUNDATION ENGINEERING, INC. I I I I I I I I I I I I I I I I I I I HODGES BARN '10-57 - ~z- fo/>-- ~ SCALE: I" = la' ,rö \~~ \\ //, (1)\ / 3~\ ~~ .\ ~~~ a.~ CD , ~\D\ \ @ It ~ \ \l-. --- f @) APPROXJMATE LOCATION OF FIELD DENSITY TEST r"T~ APPROXIMATE LIMITS OF ~"-"¡'.)Ii FILL AREA TESTE D WESTERN SOIL AND FOUNDATION ENGINEERING INC.