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HomeMy WebLinkAboutCT 75-04; 2607 Acuna Court; Soils Report Update; 1989-05-04-. - May 4, 1989 KETCHUM ENGINEERING INC. m< 7818 QUESRADA CIRCLE, CARLSSAD CALIFORNIA 92009 (619) 944-1836 01 E ENGINEERING DEPT. LIBRARY City of Carlsbad Robert Davis 7014 Llama Street Carlsbad, California 92009 2075 Las Palmas Drive KB8717 CarfsbaQ CA 92009-4859 Report #2 Subject: Updated Soils Report for Lot 91, Tract 75-4 of Map 8302, Carlsbad, California. ud;"F PCcnMkcCf Reference: Soils Investigation by Ketchum Engineering, Inc., dated March 16, 1987. Gentlemen: As per your request, we have visited the site and reviewed the above referenced soil report. Based on the findings of this review, it is our opinion that the findings, conclusions and recommendations are still valid as of this date. We appreciate this opportunity to be of professional service to you. If you have any questions, please contact our office at your convenience. - - - - - - - - - Respectfully submitted, KETCBUW ENGINEERING, INC. etchum. RCE 26267 President ENK/lk 3)Submitted KETCHUM ENGINEERING, INC. - - - - - - - SOIL INVESTIGATION FOR PROPOSED SINGLE FAMILY RESIDENCE LOT 91, TRACT 75-4, MAP 8302 CARLSBAD, CALIFORNIA PREPARED FOR: Elston Palmer 101 Copperwood Way, Suite IDI Oceanside, California 92054 PREPARED BY: KETCHUM ENGINEERING, INC. 7818 Quebrada Circle Carlsbad, California 92009 r - #-- March 16, 1987 (619) 944 -1836 CALIF.. - Elston Palmer 101 Copperwood Way, Suite 'D' Oceanside, California 92054 KE 8717 Report No. 1 - Subject: Soil Investigation for a Proposed Single Family Residence, Lot 91, Tract 75-4, Map 8302, Carlsbad, California. Gentlemen: - - We are pleased to present the results of our soils investigations for the subject project. This study was performed in accordance with your request and our proposal dated February 27, 1987. The results of our field investigation and laboratory tests, as well as our conclusions and recommendations, are presented in the accompanying report. We appreciate this opportunity to be of professional service. If you have any questions , you are welcome to contact this office at your convenience. Respectfully Submitted, KETCHUM ENGINEERING, INC. m, R.C.E. 26267 President ENK/ct cc: (5) Submitted - f- - TABLE OF CONTENTS Page - Introduction and Project Description. ....... 2 Purpose and Scope of Project. ........... 2 Field Investigation ................ 3 Laboratory Testing. ................ 4 Findings. ..................... 5 Site Description ............... 5 Subsurface Soil Conditions .......... 5 Groundwater. ................. 6 Seismic Survey and Rippability Characteristics. .. 6 Rippability Charts .............. 7 Rippability Characteristics of Cranitic Rocks. 7 Seismic Traverse - Summary of Results. .... 9 Seismic Traverse Limitations ........ .lO Conclusions ................... .12 Recommendations ................. .13 Site Preparation .............. .13 Cut and Fill Slopes. ............ .15 Foundations and Concrete Slabs-on-Grade. .. .16 Pavement and Drainage. ........... .18 Earth Retaining Structures ......... .19 Limitations ................... .21 ATTACHMENTS Plate 1 Vicinity Map Plate 2 Site Plan Plate 3 Unified Soil Classification Plates 4-9 Trench Logs Plate 10 Maximum Density & Direct Shear & Expansion Test Plates 11-15 Seismic Traverses Plate 16 Weakened Plane Joint APPENDIX Recommended Grading Specifications - XE 8717 Page 2 - - -~ SOIL INVESTIGATION FOR PROPOSED SINGLE FAMILY RESIDENCE LOT 91, TRACT 75-4, MAP 8302 CARLSBAD, CALIFORNIA INTRODUCTION This report presents the results of our soils investigation for the subject site. The vicinity map for this project is presented on Plate Number 1. Plate Number 2 shows the site configuration. and the locations of our subsurface explorations. To assist in the preparation of this report, we were provided with preliminary plans that were prepared by Lewis Holston, project architect. PROJECT DESCRIPTION This project is located on the north end of Acuna Court, Ranch0 La Costa, County of San Diego, California. Development of this site is proposed to consist of constructing a two story, wood frame home with raised floors and slab-on-grade construction. PURPOSE AND SCOPE OF PROJECT The purpose of this investigation is to develop information re- garding the on-site soil conditions to determine their suitability to receive the proposed development. The scope of this study includes the following: - , - KETCHUM ENGINEERING INC. - - f- - - - - - KE 8717 Page 3 a) Explore the subsurface conditions to the depths influ- enced by the proposed construction. b) Evaluate, by laboratory tests, the pertinent engineer- ing properties of the various strata which will influ- ence the development, including their bearing capacities, expansive characteristics and settlement potential. c) Define the general geology at the site including possi- ble geologic hazards which could have an effect on the site development. d) Develop soil engineering criteria for site grading and provide design information regarding the stability of cut and fill slopes. e) Complete a seismic survey to determine the rippability characteristics of the dense on-site materials. f) Determine potential construction difficulties and pro- vide recommendations concerning these problems. is) Recommend an appropriate foundation system for the type of structures anticipated and develop soil engineering design criteria for the recommended foundation design. h) Prepare a report that presents our findings, conclusions and recommendations. FIELD INVESTIGATION Our field investigation was conducted on.February 27, 1987, and consisted of visual observations of the existing surface condi- KETCHUM ENGINEERING INC. KE 8717 Page 4 .- - tions and completion of six subsurface excavations. These exca- vations were made by means of a backhoe under the observation of our technical personnel. All soils encountered were visually classified in accordance with Unified Soil Classification System that is presented on Plate Number 3. The representative soil samples obtained were transported to the laboratory for testing. Please refer to Plates Numbers 4 through 9 for the field logs. The seismic survey for this study was performed on March 9, 1987 and included the performance of five shallow refraction engineer- ing seismograph traverses using a Bison Instrument Signal Enhance- ment Seismograph Model 1570B. The locations of the traverses are shown on the attached Plate Number 2. Results of the seismic traverses are included herein on Plates 11 through 15. A summary of these traverses is presented on Page 9. LABORATORY TESTING Laboratory testing on selected soil samples were completed in conformance with the general practices and procedures as recom- mended by the American Society for Testing and Materials (A.S.T.M.). These tests are briefly outlined below: a. Soil Sample Classification: By visual examination, the sampled soil classifications made in the field were further evaluated in accordance with the Unified Soil Classification Syste,m. The final classifications are presented on the exploratory logs. b. Field Moisture Content and Dry Soil Density: The mois- ture content in percent of the soils dry weight and the dry unit weight in pounds per cubic foot were de- termined for selected soil samples. Please refer to the exploration logs for the results of these tests. KETCHUM ENGINEERING INC. KE 8717 Page 5 C. Maximum Dry Density and Optimum Moisture Content: In accordance with the A.S.T.M. Standard Test D-1557-70, Method A, the maximum dry density, (pounds per cubic foot), and the optimum moisture content, (percent of the dry density), were established on typical samples. Plate Number 10 presents the results of these tests. d. Expansion Index: The expansion index was determined for selected soil samples in accordance with the Uni- form Building Code Standard No. 29-2 to determine their expansive potential. Please refer to Plate Number 10 for the results of these tests. FINDINGS SITE DESCRIPTION The site is a rectangular shaped parcel that is located on the, w north end of Acuna Court. Drainage on-site is by sheet flow towards the north. The site slopes gently downward and north- ward from Acuna Court. A sparce covering of the native grasses and shrubs cover the site. A 15 foot easement is parallel and adjacent to the northern property line. SUBSURFACE SOIL CONDITIONS The siteispartially capped with some fill that is a rocky, silty clay or clayey silt. This 12 to 18 inch expansive fill material was found in trench T-l, T-2 and T-3. Beneath this fill and capping the remainder of the lot are brown, silty clay, clayey silty topsoils. These materials are expansive and are dry to wet in moisture content. All of the fill and - + KETCHUM ENGINEERING INC. - KE 8717 Page 6 - - topsoils encountered were found to be loose or soft in consis- tency. Underlying these upper materials are the fractured and massive rocks of the Santiago Metavolcanic Peaks. These dense to very dense rocks classically vary in degree of fracturing and size of rock pieces. As shown on the logs, the dense mate- rials were found at depths of 34', 4', 24', Z', 3' and 18' for trenches T-l through T-6, respectively. These depths indicate practical refusal with a backhoe. GROUNDWATER Based on our investigation, we do not believe that a shallow groundwater table exists at the site. No water table was en- countered in any of the test trenches. We do not, therefore, anticipate any major groundwater related problems, either during or after construction. However, it should be recognized that minor groundwater seepage problems may occur after development of a site even where none were present before development. These are usually minor phenomena and are often the result of an alter- ation of the permeability characteristics of the soil, an altera- tion in drainage patterns and an increase in irrigation water. Based on the permeability characteristics of the soil and the anticipated usage of the development, it is our opinion that minor seepage problems may occur at random locations. It is further our opinion that these problems can be most effectively corrected on an individual basis if and when they develop. SEISMIC SURVEY AND RIPPABILITY CHARACTERISTICS The intent of the seismic refraction survey performed at the site was specifically to facilitate the project planning by determining the variations in seismic velocity of the underly- - %. - KETCHUM ENGINEERING INC. - I‘ - - KE 8717 Page 7 ing materials and to determine a reasonable approximation of the depth from the surface to the boundaries between rippable, mar- ginally rippable, and non-rippable bedrock. Six refraction seismograph traverses were extended using a Bison Instrument Signal Enchancement Seismograph Model 1570B. The traverses were located in areas where building cuts are antici- pated. The approximate location of each seismograph traverse is shown on the enclosed map on Plate 2. The seismograph's depth of investigation is closely related to the length of the seismic traverse. For a particular length of traverse, e.g., 60 feet, using a ratio of 3:1 between length and depth, we conclude that this length of survey line will de- tect the boundaries between materials of varying density and velocity to a depth of approximately 20 feet. RIPPABILITY CHARTS Due to the presence of rock-soil units, we are including three rippability charts which apply to the site conditions. Two of the charts have been developed by the Caterpillar Tractor Com- pany for use with the D-9 and D-8 Caterpillar Tractor with No. 9 Series D Ripper and No. 8 Series D Ripper, Respectively ("Hand- book of Ripping", Caterpillar Tractor Company, Fourth Edition, April, 1972). The third chart is a modification of charts by the Caterpillar Company and an article in I'Roads and Streets", September, 1967, which we feel approximately defines rippability with the D-9 using a conventional #9 Single Shank Ripper. RIPPABILITY CHARACTERISTICS OF CRANITIC ROCKS Rippable Condition (O-4,500 Ft/Sec) This velocity range indicates rippable materials which may con- sist of topsoil and weathered or decomposed rocks which may pos- - KETCHUM ENGINEERING INC. - KE 8717 Page 8 sess random hardrock floaters. These materials typically will break down into slightly silty, well-graded sand. Materials within the velocity range of from 3,500 to 4,000 fps are rippable with difficulty by backhoes and other light trench- ing equipment. Marginally Rippable Condition (4,500 - 5,500 Ft/Sec) This range is rippable with effort by D-9 in only slightly weath- ered materials. This velocity range may also include numerous areas of very dense rock with the possibilityofextensive areas of fractured material. Excavations may produce material that will partially break down into a gravelly, coarse sand containing a high percentage of cobble or boulder-sized materials. Less fractured or weathered materials may be found in this velocity range that would require blasting to facilitate removal. - Materials within this velocity range are beyond the capability of backhoes and lighter trenching equipment. Difficulty of exca- vation would also be realised by gradalls and other heavy trench- ing equipment. Nonrippable Condition (5,500 Ft/Sec and Greater) This velocity range includes nonrippable material consisting of primarily fractured materials at lower velocities with increasing hardness at high velocities. In its natural state, it is not desirable for building pad subgrade. Blasting will most likely produce oversize material requiring disposal. The upper limits of rippability have been based on Rippability Chart No. 3 utilised for this report. However, as noted in the two Caterpillar charts (Nos. 1 and 21, the upper limits of ripp- ability may sometimes be increased. KETCHUM ENGINEERING INC. - / - - - - -. - ,. 1 -~ -~ - - _- - _. _- 1 _- KE 8717 Page Chart No. 1 D9G Cat - No. 9 Series D Ripper Rippable 0 - 7,000 Chart No. 2 Chart No. 3* 9 fps Marginally Rippable 7,000 - 8,000 fps Nonrippable 8,000 t fps D8H Cat - No. 8 Series D Ripper Rippable 0 - 5,800 fps Marginally Rippable 5,800 - 6,800 fps Nonrippable 6,800 t fps D9 Cat - No. 9 Shingle Shank Ripper (Conventional) Rippable 0 - 4,500 fps Marginally Rippable 4,500 - 5,500 fps Nonrippable 5,500 + fps *This chart has been utilised for defining rippability character- istics of the subject site for this report. SEISMIC TRAVERSE - SUMMARY OF RESULTS TABLE I Length Velocit Traverse (Ft) (Ft/Sec f Depth (Ft) Rippability S-l 50 1750 O-2.75 Rippable 3000 2.75-13 Rippable 8000 13+ Nonrippable s-2 50 1900 O-7' Rippable 7000 7+ Nonrippable KETCHUM ENGINEERING INC. - KE 8717 Page 10 - - .- - -. Traverse s-3 s-4 s-5 TABLE I (CONTINUED) 50 1600 o-3.75 6500 3.75+ 50 4500 O-l 1 8000 11t 50 1750 O-3.5 3500 3.5-13 9000 13+ Rippability Rippable Nonrippable Marginally Rippable Nonrippable Rippable Rippable Nonrippable Practical economical refusal in our test excavations with the ..~ backhoe used was encountered as follows: 2. Trench No. Depth (Ft) 1 3.5 -.. 2 4 3 2.5 . . 4 2 5 3 r- 6 1.5 _~ SEISMIC TRAVERSE LIMITATIONS .~ The results of the seismic survey for this investigation reflect rippability conditions only for the areas of the traverses. However, the conditions of the various soil-rock units appear to be similar for the remainder of the site and may be assumed to possess similar characteristics. -~ 1 KETCHUM ENGINEERING INC. - KE 8717 Page 11 / .._ Our reporting is presently limited in that refraction seismic surveys do not allow for predicting a percentage of expectable oversize or hardrock floaters. Subsurface variations in the degree of weathered rock to fractured rock are not accurately predictable, but have been indicated where thought to possibly exist. - _- The seismic refraction method requires that materials become increasingly dense with depth. In areas where denser, higher velocity materials are underlain by lower velocity materials, the lower velocity materials would not be indicated by our survey. All of the velocities used as upper limits from Rippability Chart No. 3 are subject to fluctuation depending upon such local variations in rock conditions are: a) Fractures, FaultsandPlanes of Weakness of Any Kind b) Weathering and Degree of Decomposition c) Brittleness and Crystalline Nature d) Grain Size Further, the range of rippability using Caterpillar equipment may be increased using the equipment listed in Charts 1 and 2. However, it should be noted that ripping of higher velocity materials may become totally dependent on the time available and the economics of the project. Ripping of higher velocity materials can be achieved but it may become economically un- feasible. KETCHUM ENGINEERING INC. KE 8717 Pa.ge 12 CONCLUSIONS Based on the findings of this study. we conclude that with respect to geotechnical aspects, the subject site is suitable for the pro- posed project provided the recommendations contained in this re- port are fully complied with. GENERAL: The on-site soils were determined to be expansive and, therefore, will require special foundation design consideration. __ The upper topsoils are loose and not suitable to receive struc- tural loads. We therefore, recommend that they be removed and replaced as an engineered fill beneath any areas to receive new fill, building structural loads or pavements. According to the plans there is to be a 9 or 10 foot cut for the lower level of the home. According to the seismic traverses, this cut may not be feasible considering the depth to non-rippable - materials. To further complicate the condition, it is normal for the cut areas to be undercut a depth of 12 inches below the deep- est footing and backfilled with select soils to slab subgrade. This allows for ease in foundation and utility trench excavation. We strongly suggest that the home elevation be adjusted such that the maximum cuts and/or undercuts are no deeper than about 4 feet from the existing surface. In building areas where slabs-on-grade are to be utilized, we recommend that three feet of select,..non- expansive soil be imported and compacted. A raised floor system may be utilized for this home, provided all foundations are placed at least 6 inches into the rock formation and be at least 12 inches below grade. No isolated column foot- ings should be allowed. KETCHUM ENGINEERING INC. KE 8717 Page 13 RECOMMENDATIONS .- SITE PREPARATION PRECONSTRUCTION CONFERENCE: We recommend that a preconstruction conference be held at the site with the developer, civil engineer, contractor, and geotechnical engineer in attendance. Special soil handling and the grading plans can be discussed at that time. SPECIFICATIONS: We recommend that all earthwork be done in accordance with the attached "Recommended Grading Specifications.n Ketchum Engineering, Inc., should observe the grading and test compacted fills. All special site preparation recommendations presented in this report will supercede those in the standard Recommended Grading Specifications. All embankments, structural fill and fill should be compacted to not less than 90 percent of the maximum laboratory density. Utility trench backfill within 5 feet of the proposed structures and beneath asphalt pavements should be compacted to not less than 90 percent 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 1557-70. DEMOLITIONS, CLEARING AND GRUBBING: During site preparation, all debris and deleterious materials derived from demolition, clearing and grubbing operations should be legally disposed of off-site prior to grading. Any existing utilities that will not be utilized should be removed and properly capped at the property lines. The removal of trees should include the removal of their roots. The depressions resulting from the above operation should be backfilled with soil that has been compacted to at least 90% relative compaction. -, i KETCHUY ENGINEERING INC. - K .- t KE a717 Page 14 GENERAL: Beneath all areas to receive fill, structural loads, sidewalks, or pavements. we recommend that the alluvial materials, topsoils, and fill be removed to firm natural ground and stock- piled for future use. Firm natural ground is defined as soil that possesses an in-place density equal to, or greater than, 85% of its maximum dry density or the Santiago Metavolcanics rocks. The bottom of the excavation should be scarified to a depth of at least 6 inches, water as required, and densified to at least 90%. The stockpiled soils may then be replaced and compacted to at least 90% in 6 to 8 inch lifts to desired grade. SELECTIVE GRADING FOR STRUCTURES: It is suggested that for that portion of the home that is to have exterior sidewalks and slabs- on-grade construction that the subgrade be capped with at least 3 feet of select, non-expansive soil. It has been our experience that this condition provides an economical solution and also pro- vides a lower potential for future problems. TRANSITION AREAS: We recommend that the cut area beneath struc- tures be undercut to a minimum depth of 1 foot below the base of the deepest footing. This recommendation is submitted in an attempt to reduce the potential distress that could arise from footings founded partially on cut and partially on fill. MOISTURE CONTENT OF FILL SOILS: All fill soils placed should have moisture contents of at least 2% over optimum moisture con- tent. AREAS TO BE PAVED: All areas to be paved should have the subgrade soils densified to at least 90% relative compaction to a minimum depth of 12 inches. It is suggested that the upper 12 inches of subgrade soils be comprised of granular select, non-expansive materials. IMPORT MATERIALS: Any fill material to be imported on-site should consist of granular, non-expansive soil that contains no KETCHUM ENGINEERING INC. - .- - _.. ,.~ KE 8717 Page 15 organic or deleterious materials. It should have sufficient cohesion to hold a vertical, or near vertical, cut for footing excavations. It should have at least 85% of the material pass- ing the number 4 sieve with no rocks or chunks larger than 14 inches. The import fill should be approved by our office prior to on-site delivery. CUT AND FILL SLOPES It is our opinion that cut and fill slopes constructed from the native on-site materials will be stable with relation to deep- seated failures if constructed at, or flatter than, the following recommended slope ratios expressed in the horizontal or vertical units for the indicated heights: Cut Slopes to 20 Feet in Height Cut Slopes to 15 Feet in Height Fill Slopes to 18 Feet in Height 2:l 1.5:1 2:l i - s The above maximum heights were determined by using a factor of safety of 1.5. It is also recommended that footings not be founded nearer than 8 feet measured horizontally inward from the face of the slopes. Slopes should be planted with erosion resisting plants and natural drainage should be directed away from the top of all slopes, such that no water is allowed to flow over the top. TEMPORARY SLOPE STABILITY: The following table presents recom- mendations relative to temporary construction excavations. These slopes should be relatively stable against deep-seated failures but may experience localized sloughing. Slope Ratio Maximum Height of Temporary (Horizontal to Vertical) Excavation (Feet) 0.25 : 1 Vertical 12 5 KETCHUM ENGINEERING INC. KE 8717 Page 1.6 - #- -5 It should be the contractor's responsibility to provide safe support for the excavation. No heavy equipment should be allowed adjacent to the top of the temporary cuts. - - FOUNDATIONS AND CONCRETE SLABS-ON-GRADE -. NONEXPANSIVE SUBGRADE SOILS WITH SLABS-ON-GRADE: We recommend the structure proposed for this project be supported by a con- tinuous spread footing foundation system as recommended below. The following recommendations are submitted provided the soils - within the upper 3 feet from finish grade have a low expansive potential. - a) a - b) cl d) All footings for one and two story structures should be founded a minimum of 12 and 18 inches respectively below adjacent finish grade. Footings should have a minimum width of 12 inches. Both exterior and interior continuous footings should be reinforced with one No. 4 bar positioned 3 inches above the bottom of the footings and one No. 4 bar positioned 3 inches clear below finish floor. Interior slabs should be not less than 3$ inches in thickness, underlain by a !+ inch blanket of clean sand or crushed rock, reinforced with 61~x6~8-#10/#10 welded wire mesh and completely surrounded with a continuous footing. Exterior slabs should be a minimum of 34 inches in thickness and should be reinforced with 6"x6"-#lo/#10 welded wire mesh. KETCHUM ENGINEERING INC. - /. - - - i.. - KE 8717 Page 17 e) Surface drainage should be directed away from the proposed foundation. Planters should be constructed so that water is not allowed to seep beneath founda- tions or slabs. Over-irrigation of areas adjacent to foundations and slabs should be avoided. f) Prior to placing concrete, the foundation excavations should be inspected by a representative of this office to insure that the above recommendations have been followed. EXPANSIVE SUBGRADE SOILS WITH A RAISED FLOOR SYSTEM: The follow- ing recommendations are submitted provided the soils within the upper 3 feet from finish grade have a high expansive potential. a) All footings for one and two story structures should be founded at least 611 into the dense metavolcanic rock and a minimum of 12 inches respectively below adjacent finish grade. Footings should have a minimum width of 12 inches. b) Both exterior and interior continuous footings should be reinforced with two No. 4 bars positioned 3 inches above the bottom of the footings and two No. 4 bars positioned 3 inches clear below finish floor. Nb isolated column footings are allowed. - - .- h - c) Exterior slabs should be a minimum of 4 inches in thickness and should be reinforced with 6vx6~~-#10/#10 welded wire mesh. Please refer to Plate NO. 16 for additional slab-on-grade requirements. d) Surface drainage should be directed away from the proposed foundation. Planters should be constructed so that water is not allowed to seep beneath foundations or slabs. Over-irrigation of areas adjacent to founda- tions and slabs should be avoided. KETCHUM ENGINEERING INC. KE 8717 r - - - k. - 7 - e) Prior to placing concrete, the foundation excavations should be inspected by a representative of this office to insure that the above recommendations have been followed. IEARING VALUE: An allowable soil bearing value of 2000 pounds per square foot for spread footing foundations may be used for design of the on-site structures. This bearing value should be verified for all soil conditions under all building pads. In our opinion this value can be increased by one-third for loads that include wind or seismic forces. SETTLEMENT CHARACTERISTICS: The anticipated total and/or dif- ferential settlements for the proposed structure may be considered to be within tolerable limits provided the recommendations pre- sented in this report are followed. PAVEMENT The following recommendations are submitted as preliminary guide- lines for pavement construction. The subgrade soils to a depth of at least 12 inches should be densified to at least 90%. Paved areas should be protected from moisture migrating under the pave- ment from adjacent water sources such as planted or grass areas. Saturation of the subbase soils could result in pavement failures. Further, all paving materials and methods of construction should conform with good grading practices and with the minimum re- quirements of the governing agency. DRAINAGE We recommend that positive measures be taken to properly finish grade the pads once improvements and landscape are in place so that drainage waters are directed off the pads and away from possible foundations, floor slabs, and slope tops. No areas of ponded water should be allowed to exist. KETCHUM ENGINEERING INC - KE 8717 Page 19 - r - - - ‘. - .-, - EARTH RETAINING STRUCTURES GENERAL: It is our understanding that the small retaining struc- tures that are proposed for this project will be of masonry con- struction. ULTIMATE ACTIVE PRESSURE: The ultimate 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 35 pounds per cubic foot for walls free to yield at the top (un- restrained walls). For walls restrained at the top, a fluid pressure of 45 p.c.f. may be used'. These pressures do not con- sider any surcharge loading. If any surcharge loadings are an- ticipated, this office should be contacted for the necessary increase in soil pressure. All earth retaining structures should have adequate weep holes or a subdrain system to prevent the buildup of hydrostatic pressure behind the wall. ULTIMATE PASSIVE PRESSURE: The passive pressure for prevailing soil conditions may be considered to be 350 pounds per square foot per foot of depth. This pressure may be increased one-third for seismic loading. The coefficient of friction for concrete to soil may be assumed to be 0.40 for the resistance to lateral movement. When combining frictional and passive resistance, the latter should be reduced by one-third. ALLOWABLE SOIL BEARING PRESSURE: The foundation for the proposed retaining structures should consist of spread footings founded in the firm native soils or compacted fill. Firm natural ground is defined as soil having an in-situ density of at least 85% of its maximum dry density. Footings may be designed for an allow- able bearing pressure of 2000 p.s.f. FACTOR OF SAFETY: The above values, with the exception of the allowable soil bearing pressure, do not include a factor of safety. Appropriate factors of safety should be incorporated into the design of all earth retaining structures to reduce the possibility of over turning and sliding. KETCHUM ENGINEERING INC. F” - - - - - - .- + - KE 8717 Page 20 BACKFILL: All backfill soils should be compacted to at least 90% relative compaction. Expansive or clayey soils should not be used for backfill material within a distance of 5 feet from the back of the wall. The retaining structure should not be backfilled until the materials in the wall have reached an adequate strength. KETCHUM ENGINEERING INC. - c - LIMITATIONS - - - - I - The recommendations presented in this report are contingent upon our review of final plans and specifications. The soil engineer should review and verify the compliance of the final grading plan with this report. It is recommended that Ketchum Engineering, Inc., be retained to provide continuous soil engineering services during the earth- work operations. This is to observe compliance with the design concepts, specifications or recommendations and to allow design changes in the event that subsurface conditions’differ from those anticipated prior to start of construction. The recommendations and opinions expressed in this report reflect our best estimate of the project requirements based on an eval- uation of the subsurface soil conditions encountered at the sub- surface exploration locations and the assumption that the soil conditions do not deviate appreciably from those encountered. It should be recognized that the performance of the foundations may be influenced by undisclosed or unforeseen variations in the soil conditions that may occur in the intermediate and unex- plored areas. Any unusual conditions not covered in this report that may be encountered during site development should be brought to the attention of the soil engineer so that he may make mod- ifications if necessary. This office should be advised of any changes in the project scope or proposed site grading so that it may be determined if the recommendations contained herein are appropriate. This should be verified in writing or modified by a written addendum. The findings of this report are valid as of this date. Changes in the condition of a property can, however, occur with the passage of time, whether they be due to natural processes or the work of man on this or adjacent properties. In addition, changes KETCHUM ENGINEERING INC. 4- - - - - - - in the state-of-the-art and/or government codes may occur. Due to such changes, the findings of this report may be invalidated wholly or in part by changes beyond our control. Therefore, this report should not be relied upon after a period of two years without a review by us verifying the suitability, the con- elusions, and recommendations. In the performance of our professional services, we comply with that level of care and skill ordinarily exercised by members of our profession currently practicing under similar conditions and in the same locality. The client recognizes that subsurface con- ditions may vary from those encountered at the locations where our borings, surveys, and explorations are made, and that our : data, interpretations and recommendations are based solely on the information obtained by us. We will be responsible for those data, interpretations and recommendations, but shall not be res- ponsible for the interpretations by others of the information developed. Our services consist of professional consultation and observati,on only, and no warranty of any kind whatsoever, expressed or implied, is made or intended in connection with the work performed or to be performed by us, or by our proposal for consulting or other services. or by our furnishing of oral or written reports or findings. It is the responsibility of the owners, or their representative to ensure that the information and recommendations contained herein are brought to the attention of the engineer and arch- itect for the project and incorporated into the project’s plans and specifications. It is further their responsibility to take the necessary measures to ensure that the contractor and his subcontractors carry out such recommendations during construc- tion. - t Inspection services allow the testing of only a very small per- centage of the fill placed at the site. Contractural arrange- ments with the grading contractor should contain the provision KETCHUM ENGINEERING INC. - / - that he is responsible for excavating, placing and compaction of fill in accordance with the project specifications. In- spection by the geotechnical engineer during grading should not relieve the grading contractor of his primary responsibility to perform all work in accordance with the specifications. - - - . . \ - - - This firm does not practice nor consult in the field of safety sngineering . We do not direct the contractor’s operations, and we cannot be responsible for the safety of other than our own personnel on the site; therefore, the safety of others is the responsibility of the contractor. The contractor should notify the owner if he considers any of the recommended actions presented herein to be unsafe. - - 8 - KETCHUM ENGINEERING INC. - - - - VICINITY MAP JOB NO. 8717 7616 QUEERADA CIRCLE, C A RLSBAD (619) 944-1636 PLATE NO. 1 I - - - i , ACUNA COURT i LEGEND: N Backhoe Trench Location / Seismic Traverse Location SITE PLAN BY: ENK K ETCHUM ENGINEERING INC.rx 7616 QUEERADA CIRCLE, C A RLSBAD (619) 944-1636 JOB NO. 8717 DATE: 3/l 7/87 PLATE NO. 2 UNIFIED SOIL CLASSIFICATION MORE THAN HALF LIOLIID LIMIT IS ussnlAN 50% uoulo UMIT IS GREATER TM&N 50% GRAIN SIZE U.S. STAMX40 SERIES SIEVE-I- CLEAR SOIMRE SIEVE OPENINGS - 200 40 lc 4 3A’ 3* 12” SAND GRAVEL SILTS AN0 CLAYS COBBLES N3u.DERs FINE HEOIUM CDARSE FINE CLUIY RELATIVE DENSITY CONSISTENCY 7 SANDS.GWELS AN3 NON- PLASTIC SILTS B”)ws/FOOT UAYS AN0 PLASTIC SILTS STRENGTH WOWS/FOOT VERY UIOSE o- 4 VERY SOFT 0 - l/4 o-2 LOOSE 4 - 10 SOFT l/4 - ln 2 -4 FIRM la - 1 4-6 HEOUM DENSE 10 - To STIFF l-2 6 - 16 DENSE a -50 VERY STIFF 2 - 1 16 -En. VERY DENSE WER 50 HARD OVER 4 OVER 32 Jz- Water level at time of excavation or as indicated 0” Undisturbed driven ring or chunk sample Disturbed bulk sample By: ENK JO0 NO. 8717 KETCHUM ENGINEERING DATE: 2127187 7818 OUEBRADA CIRCLE, INC.?m (619) 944-1636 C A RLSBAD PLATE NO. 3 L r .- 1 1 1 1 J -I J ‘J 1 -I J 1 1 1 7 L I : ;1 0 1 2 3 4 5 6 7 a 9 10 11 12 13 1.4 1; i ; i: l , y ‘;; : ; 3 :M a ;M - - - TRENCH NUMBER T-1 ELEVATKJN OESCRIPTION FILL: Orange-brown rocky clayey silt TOPSOIL: Brown rocky s11t METAVOLCANIC ROCK BOTTOM Practical refusal Loose- Med.Den; Loose Very Dense ii ‘r MO :E cu :z := : 1 BY: ENK 1 JO@ NO. 8717 1 KETCHUM ENGINEERING INC. m DATE: 2127187 7818 QUEBFIADA CIRCLE, C A RLSBAD (619) 944-1636 92000- PLATE NO. 4 t 3 4-- 5- 6- 7- a- 9- 10 - 11 - 12 - 13 - 14 - 1; - - - - lRENCH NUMBER T-2 ELEVATION OESCRIPTION FILL: - Brown/tan clay TOPSOIL: Brown silty clay Tan METAVOLCANIC ROCK BOTTOM Practical Refusal Wet Wet Moist : a L- ;; ,o E 0 soft Soft Med. Stiff Very Dense I BY: ENK I JOB NO. 8717 -w ~ 1 K ETCHUM ENGINEERING INC. -a DATE: 2/27/87 7818 OUEBRADA CIRCLE * C A RLSBAD (619) 944-1636 92000 _ PLATE NO. 5 v i I 5- 6- 7- a- 9- 10 - 11 - 12 - 13 - 14 - 1; - IRENCH NUMBER T-3 ELEVATION OESCRIPTION 7ILL: m Lt. tan clayey lOPSOIL IETAVOLCANIC ROCK 30TTOM 'ractical Refusal Wet Dry Very Dry ,z- =rC mum c;t :;a al= l oo v Soft Soft llery lense - II 0y= ENK JOB NO. 8717 K ETCHUM ENGINEERING INC. DATE: 2/21/87 7818 QUESRADA CIRCLE * C A RLSBAD (6191 944-1636 PLATE NO. 6 0 1 T 2 3 f 4- 5- 6- 7- a- 9- 10 - 11 - 12 - 13 - 14 - 1; 1 TRENCH NUMBER T-4 ELEVATION I METAVOLCANIC ROCK - refusal Wet Very Dense K ETCHUM ENGINEERING INC. 7618 DUESRADA CIRCLE I C A RLSBAD . (619) 944-1636 92000 BY: ENK 3 4- 5- 6- 7- a- 9- 10 - 11 - 12 - 13 - 14 - 1; - - - lRENCH NUMBER T-5 ILEVATION DESCRIPTION POPSOIL: Brown clayey 311t Lt. orange clayey silty rractured rock 4ETAVOLCANIC ROCK 30TTOM ?ractical refusal Dry . l > cvc zz- YYal a*2 l zw =alo l o’s 0 Soft Dense Very Dense JO0 NO. 8717 K ETCHUM ENGINEERING INC. 7010 QUEBRADA CIRCLE s C A RLSBAD (619) 944.*a== l”“” o?nn a PLATE NO.8 ,- -1 1 2 3 4- 5- 6- 7- a- 9- 10 - 11 - 12 - 13 - 14 - 1, - z ; l !U > y ,;; m : 0 rlL/ :L 7 ;M - \ 1 IRENCH NUMBER T-6 ** I- 0 ZXC YYDo E ELEVATION a$t 2;: k x l 0g OESCRIPTION u ? 'OPSOIL: s Brown clayey Wet Soft f - ,t. orange clayey silty Dry Dense f 'ractured rock - - [ETAVOLCANIC ROCK Very Dense z IOTTOM E 'ractical refusal 0y' ENK KETCHUM ENGINEERING INC. x 7010 QUE~RACIA CIRCLE. C A RLSBAD (619) 944-1836 JO0 NO. 8717 DATE: 2/27/87 PLATE NO. 9 t I 1 c 1 1 ; c 1 1 1 1 1 MAXIMUM DENStTY & OPTIMUM MOISTURE ‘CONTENT *STY: 1557-78 Madmum Description Opt hum yp Ndrtur. Brown silty clay w/some rock fragmentif 117 12.5 I I I I DIRECT SHEAR TEST RESULTS Sample Description Angk of Cohorion Intomrl Inlorco~8 Frlcllon 1 ‘I lpcfl EXPANSION TEST RESULTS EXPANSION INDEX 102 I I I I BY: ENK I JOB NO. 8717 ‘1~ I K ETCHUM ENGINEERING INC.rx DATE’ 3/17/87 7810 QUE~RADA CIRCLE, C A RLSBAD I (619) 944.1636 PLATE NO. 10 1~ I , I I I 1 I i :‘, I / I I , I I .\ I --:-. 1. /!!;;i’ +I+-- !;;;I:’ .<,:;~ .,.,. _ ‘-I.! :’ : I :--. .e.. !: - ‘~I -s:ii:;i +-i--j- !I ~. I. -~-~. ._ ;. ,ilI’ . :.~, .,,, gT?T. .~.x:,:;; I .-. . I ..,il.,. .ii.;,: . _ < _ . 4 l20 120 42 l2oloo20 no a040 904030 604020 : c I l + ‘:iI.: . . . . ;!:::’ .‘:.,i._ , 8. ., ,_ ., .~ . .!.. ..,. ! !I, ,ii ::I;, ?. ,. _.. ~I ‘I ,. ._ (.,... ..:.,.a. ; ; .’ : ,, I.. 3 ~~ I.. .~ I..., .a., ., ..,~ ,.:: -- . c. ,,.....i : 1: : 1:;r !.‘.- 1. ’ I +; .-_ c . _, 1 -7. $ . 1 1 -. * t I , . - . . . . 1 4 , ., I ,..‘I .: ‘. _ .. : 0 ..:‘!:. 4 _. ~. .,. .,. 0~ . . ..a. .~:: , ;;’ : :.I::.:’ . . ,. - : .;.;!: I ..~ , ,.A I 1. ., . . ..C.. .I,_.;. :.,. I , ! I ,!’ .- ., .v 1 r .i: ,. ., I I 1 i _) I, ‘I, , ,i. .‘ I I In c- N .ll cl” -- I i”’ s’l DISTANCE __+ loa PALMER GEOLOGIST RS K ETCHUM ENGINEERING INC. JO2 NO. 8717 ELEVATION 1010 OUEBRADA CIRCLE * C ARLSBAD t616) 644-1636 TRAMRSE NO. s-1 SURFICIAL MAT’L. TRAMRSE TWE ~K,VPE METAVOLCANIC ROCK I I I I I I I f I , I I 1 I “I ’ -._-. . _ ; i!: -1~‘-.? 1.. 4,~ : i : : ! i Ii+ # .Aj : 2.~~ ,~~:- --r :.-._ :.i7 4 .A ‘-- :-. i. y’jf~;] Ii iI I .,;1;,:: !. ,,‘.. .I. : .., 1 : I. I~;-. ,..!:~ I:,~ ,, :,. . :I.. .:i:fTTT ..I,.. ._jI in.. .., +, :I!. I20 120 a wm20 I20 0040 904020 w4020 :I ~. . I !-. T :I Ii _...... .--Ii,., ..ii.;.. I::: 1,1;,_. ,.I.. : ,,. ..~ ., .I ~. ,, ., / ..I .I, . , I,., i I 8. . . ..+~. .a.:... :.,_ . . .~. 2. .~. ~A,.?.. . . . . . ..I ..’ : 4 . . ... : .:., /]I :~.I( ., ,.. .b,! : & I - _ I .., ..t;: .,,. : .,, I. I I :-:+Gl -a , : 4:. , : ‘i;.‘.~’ ,...~. ~.,... ,, ..,. ~,.~ ;J f j;: .: ._+ i ,. .I 7-j : ,_~. ,. .;.. ., 1 i : :: :~ . ..i<.. .i:-‘:~ . . . . ..i ..i. I ..,... : ; : 1 ,. :/ i , : .: : “ii’. .l - .A., .yj . ../ .: , 4 c i ! 6. :,,~I . I --?I 80 IO0 I20 I40 MO l20 200 no I20 ID0 210 NO 270 a20 w PALMER CEDLOCIST RS DISTANCE - IOBNO. 8717 ELEVATION (616) 644-1636 TRAVERSE ND. s-2 SURFICIAL MAT’L. TRAVERSE 1 WE KDCK TYM METAVCLCANIC ROCK I I I 1 I I I i f. I I I I I I I 1.7 : : IiYf~~~.~ ..A,. I -.- 7 .‘..!, :;:;j.i!f ._:_. :, J!.i! ia. y-- I $;!11 .j,:~.. .,. .., ,.~. ,,L.i -.... - . 7 I ,jl:; .,I:: i+Y-eT f ,~ ;ir.: __. . ..! . , : :;I :.:I: :. *.. ./ t . ._ .~. _ . ~-+.,. .,__,.I ! .,.~ 8: _ .I .,.r:. I., ,. ,/ I ;;’ : , .~. ..i: , : ! .:..a. ! ! , ; : t :.I.~ 3. %. ., ..~ ‘1 .~ 4 I , I, 1 ,.i zi -----2 d , , , -- DISTANCE - 20 40 40 Jo 20 I20 wo l50 140 210 270 m PALMER GEOLOGIST it? IDR NO. 8717 ELEVATION TRAVERSE NO. s-4 SURFICIAL MAT’L. TRAVERSE TYPE RmK,Yfl METAVOLCANIC ROCK I / I I ! I I ; c--‘, / I 1 I I I I ly I I . .X(~~Ty ..I ,... .~ ~.~-~---T . ...!. _ ,I I .,.::!!j F L "ix :::;i-c I- -. .:;.!I;: : I~, _- i F .;y . L. ~.__.. _ . .-. I- I ,4.f. L -.;*_~ .~ i : I :-~.-’ .,..!:, - ; : ‘1~ \ . . . ;::. -22 I 3 10 100 El 200 200 7: ; in; ; i ., ‘;;l!.;. , 1 --I : -’ ‘i.I::.iTj 1. ,I.,. II--- ..~ ;: ,~ I : - !;f ! - i ,. ., ..I i : A _~_.. .? ,i!ll :’ ,,iiY L I20 120 w I5omo50 120 Ro 40 9040x) 404020 ,, .,, # .(.... :I:“’ ,./i.. : __. . is,.,. .i..,.: _ . ~I :.;..... . : _._I. ..~ :, ,_../ .ir.: !. ~.... ., ., ,I . ,. .I~ ‘:“I ;i ,,;i, ,: . 9 : .,.. I ..i .’ .s. I. ,::;I’ 1 ::. / * : i’ ..,. ,...C.~ .>,_... :a. I:‘, : : ..:. “-’ : ,. ..i.’ :‘;::I: . . ,. .~ 8 / , ye: I ,. ., !; ! ,,a. 9. ,, ,I. 65( / -- 80 l&o 240 20 40 40 20 40 90 40 80 120 20 loo I20 DISTANCE - w PALMER GEoloGlST RS 108NcJ. 8717 ELEVATION TRAVERSE NO. s-3 SURFICIAL MAT’L. TRAVERSE TWE ROCK TYPE METAVOLCANIC ROCK , ai ) .F I / I I : e I i / ! 1 I I 1% 1 -.... .,_ .i!I : I :r’ t 3 .,..:, ! ~, 1 ~:i:(~TrT~. , ( -.:-~ ,. :.‘I!,;! I : i 7 . . i , .#..(,~ ‘. ’ i !~I +- ~.,.. ..I,..11 . 11 I I iL7 ..:Jii” -1. :L;cJ - . . . . . ..t.:.- -. , . .-- 1: , _. 4 ‘~1 _ : :y+; +- *A .:. ..~ -’ : . --. ~1. ‘i::::. .._*... I,..:’ - ,~ .._I i 1 I .I. .,, ;;. f-y-- ,!jf.l;] .,t;;~ :lI. ;-i:-- . . ~. , 6 i - ml2040 I2oIoo20 I20 a040 904030 404020 .,I... ;i;‘:~ : I I : / : I 5 _-. . ...,,.,: ..ii.,., ., ~. ., .._. ., ‘ . --. - .~ ._.. ._. .~.. ._ ,..... ..a:...,. ” : * ., ., ; i :::; . .1,. : .,., ,... .:.~ f “’ A , : 81.’ ~...I. ..i. .,. i : ,. ..s. ..__+.., _I...,. :.,.. . I .,::!:Y ,. . , ! ., .,i, ;: ., * , .., I ~, I .’ i ( ,I ~. .: ; : , . 1 1, l-r :I ;; / L I- m . e-y .r4 * n ,I, ,. ..(, 9ooc (f~. : I -19 I 40 20 40 70 a0 90 100 80 m I20 z Im no 200 120 w IO0 240 276 300 )oe Palmer GEOLOGIST RS DISTANCE - (616) 944-1836 KNINO 8717 TRAMRSE No. s-5 TRAVFRSE 1 WE ELEVATlDN SURFICIAL MAT’L. ROCK TYPE Metavolcanics - . APPENDIX A RECOMMENDED GRADING SPECIFICATIONS -. -. - 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 soil to the lines and grades shown on the accepted plans. The recommendations con- tained in the preliminary soil investigation report are a part of the recommended grading specifications and shall supersede the provisions contained hereinafter in the case of conflict. Inspection and Testing A qualified soil engineer shall be employed to observe and test the earthwork in accordance with these specifications. It will be necessary that the soil engineer or his representative pro- vide adequate observations so that he may provide a memorandum that the work was or was not accomplished as specified. Deviations from these specifications will be permitted only upon written authorization from the soil engineer. It shall be the responsi- bility 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 the memorandum to the owner and govern- mental agency, as required. If in the opinion of the soil engineer, substandard conditions are encountered, such as questionable soil, poor moisture control, inadequate compaction, adverse weather, etc., the contractor shall stop construction until the conditions are remedied or corrected. Unless otherwise specified, fill material shall be compacted by the contractor while at a moisture content near the optimum - 1 -, KETCHUM ENGINEERING INC. - - ,f- -~ I - .-. moisture content to a density that is not less than 90% of the maximum dry density determined in accordance with A.S.T.M. Test No. D 1557-70, or other density test methods that will obtain equivalent results. Clearing and Preparation of Areas to Receive Fill All trees, brush, grass, and other objectionable material shall be collected, piled, and burned or otherwise disposed of by the contractor so as to leave the areas that have been cleared with a neat and finished appearance free from unsightly debris. All vegetable matter and objectionable material shall be removed by the contractor from~the surface upon which the fill is to be placed, and any loose or porous soils shall be removed or com- pacted to the depth determined by the soil engineer. The surface shall then be plowed or scarified to a minimum depth of 6 inches until the surface is free from uneven features that would tend to prevent uniform compaction by the equipment to be used. When the slope of the natural ground receiving fill exceeds 20% (5 horizontal to 1 vertical), the original ground shall be stepped or benched as shown on the attached Plate A. Benches shall be cut to a firm competent soil condition. The lower bench shall be at least 10 feet wide and all other benches at least 6 feet wide. Ground slopes flatter than 20% shall be benched when considered necessary by the soil engineer. Fill Material Materials for compacted fill shall consist of any material import- ed or excavated from the cut areas that, in the opinion of the soil engineer, is suitable for use in constructing fills. The material shall contain no rocks or hard lumps greater than 12 inches in size KETCHUM ENGINEERING INC. Unforeseen Condition ,F“ In the event that conditions are encountered during the site pre- paration and construction that were not encountered during the pre- liminary soil investigation, Ketchum Engineering, Inc., assumes no responsibility for conditions encountered which differ from those _- conditions found and described in the preliminary soil inirestiga- tion report. - - KETCHUM ENGINEERING INC. - The surface of fill slopes shall be compacted and there shall be "~ no excess loose soil on the slopes. Inspection - Observation and compaction tests shall be made by the soil engin- - eer during the filling and compacting operations so that he can state his opinion that the fill was constructed in accordance with - the specifications. .- The soil engineer shall make field density tests in accordance with A.S.T.M. Test No.D1556-70. Density tests shall be made in the com- .~. pacted materials below the surface where the surface is disturbed. When these tests indicate that the density of any layer of fill or portion thereof is below the specified density, the particular - layer portion shall be reworked until the specified density has been obtained. 8. The location and frequency of the tests shall be at the soil engin- .~ eerls discretion. In general, the density tests will be made at an interval not exceeding two feet in vertical rise and/or 500 - cubic yards of embankment. Protection of Work During construction, the contractor shall properly grade all exca- vated surfaces to provide positive drainage and prevent ponding of water. He shall control surface water to avoid damage to adjoin- ing properties or to finished work on the site. The contractor shall take remedial measures to prevent erosion of freshly graded - areas and until such time as permanent drainage and erosion control features have been installed. - - KETCHUM ENGINEERING INC. - - ‘L - - - and shall contain at least 40% of material smaller than l/4 inch in size. (Materials greater than 6 inches in size shall be placed by the contractor so that they are surrounded by compacted fines; no nesting of rocks shall be permitted.) No material of a perish- able, wow 9 or otherwise improper nature shall be used in filling. Material placed within 36 inches of rough grade shall be select material that contains no rocks or hard lumps greater then 6 inches in size and that swells less than 3% when compacted as hereinafter specified for compacted fill and soaked under an axial pressure of 1~50 psf. Potentially expansive soils may be used in fills below a depth of 36 inches and shall be compacted at a moisture content greater than the optimum moisture content for the material. Placing Spreading and Compacting of Fill Approved material,shall be placed in areas prepared to receive fill in layers not to exceed six 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 to a minimum spec- ified density with adequately sized equipment, either specifically designed for soil compaction or of proven reliability. Compaction shall be continuous over the entire area, and the equipment shall make sufficient trips to insure that the desired density has been obtained throughout the entire fill. When the moisture content of the fill material is below that speci- fied by the soil engineer, the fill material shall be aerated by the contractor by blading, mixing, or other satisfactory methods until the moisture content is as specified. - KETCHUM ENGINEERING INC. 1 !- 1 1 1 1 1 1 1 4. d 1 1 1 1 1 1 t .i w + w/2 ; w/2 , . I > TRANSVERSE ‘i... $ WEAKENED -Y ,.. I ,__. ‘..‘.., :, :. PLANE JOINTS . . .;.. . . 6’ ON CENTER (MAX. ;. .;,:. @ . . . . . ‘. ; ‘_. ‘.’ : ..::;. : .‘.‘. .:, I .;. ., .. 3’ ..’ .’ ‘, ,.. ,.‘. . . .._ .:.,, .;: 1 10’ I 6’-l0’ I SLABS IN EXCESS OF 10 FEET IN WIDTH SLABS 6 TO lD FEET IN WIDTH 4 PLAN n&3. tt l/e” TO l/4=, JOINT SEALER 6”x6’ - IO/IO W WM STRIP IN ADDITION TO CON- TINUOUS REINFORCEMENT DETAIL n.1.s. WEAKENED PLANE JOINT FOR EXTERIOR SLABS % BY: ENK JOB NO. 6717 1 KETCHUM ENGINEERING INC.rm DATE: 3/17/87 7616 OUEBRADA CIRCLE, I C A RLS6AD (619) 944-1636 PLATE NO. 16