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Home My WebLink About1261 Vancouver Avenue - Technical Study, ' GEOTECHNICAL SITE INVESTIGATION 1261 Vancouver Avenue Burlingame, California Y & A J03 - 1084 By Jae H. Yang - Project Engineer J. YANG AND ASSOCIATES .� � J. Yang and Associates GEOTECHNICAL / ENVIRONMENTAL CONSULTING ENGINEERS 2758 CANYON CREEK DR. � SAN RAMON, CA 94583 (925) 831-8678 � FAX (925) 831-3645 Project No. J03-1084 April 20, 2003 Mr. Otto Miller Subject: Proposed Residence at 1261 Vancouver Ave Burlingame, California Geotechnical Site Investigation Dear Mr. Miller: In accordance with your authorization, J. Yang and Associates has investigated the geotechnical site conditions at the subject site of the proposed of housing development in Burlingame, California. The accompanying report presents our conclusions and recommendations based on our investigation. Our evaluations indicate that the site is physically suitable for the proposed construction provided the recommendations of this report are carefully followed and are incorporated into the plans and specifications. Should you information, convenience. have any questions or require additional please contact our office at (925)831-8678 your Very Truly Yours, J. Yang and Project Geo. ociates ineer ❑ ProjectNo. J03-1084 TABLE OF CONTENTS Page No. LETTER OF TRANSMITTAL GEOTECHNICAL ENGINEERING INVESTIGATION Site Location and Description Purpose and Scope FIELD EXPLORATION AND LABORATORY TESTING GEOTECHNICAL EVALUATION AND DISCUSSION Site Geology and Slope Stability Subsurface Soil Condition 1 1 2 3 5 5 CONCLUSIONS AND RECOMMENDATIONS 6 General 6 Site Preparation and Grading 7 Surface and Subsurface Drainage 8 Foundations 8 Retaining Walls 9 Slab-on-Grade Floors 10 Flexible Pavement 11 Trench Backfill/Observation and Testing 12 PLAN REVIEW, CONSTRUCTION OBSERVATION GUIDELINES FOR REQUIRED SERVICES 14 15 LIMITATIONS AND UNIFORMITY OF CONDITIONS 17 APPENDIX AA Site Plan, Boring Location and Boring Logs J. YANG AND ASSOCIATES n Project No. J03-1084 I. INTRODUCTION A. Location and Description of Site This report presents the results of a site investigation performed by J. Yang and Associates for the property of 1261 Vancouver Ave., Burlingame, California. (See PLATE 1-Location Map). The site was investigated by J. Yang and Associates on April 17, 2003. The property is located at west side of Vancouver Ave. The ground slopes down to the street from the site. The site is currently well developed flat lot with with left side property line. Most of the site is covered with landscaped flat lot with existing residence. Development plans call for construction of a new single family residence. B. Purpose and Scope of Work The purpose of our site Investigation for the proposed family dwelling house at 1032 Cabrillo Ave, Burlingame, California was to determine surface and subsurface soil conditions at the subject site. Based on the results of the investigation, criteria were established for the grading of the site, the design of foundations for the proposed structures, and the construction of other related facilities on the property. Our investigation included the following: 1. Field reconnaissance by the Soil Engineer 2. Drilling and sampling of the subsurface soil. 3. Laboratory Testing. 4. Analysis of the data and formulation of conclusion and recommendations. 5. Preparation of this written report. 1 J. YANG AND ASSOCIATES Project No. J03-1261 II. FIELD EXPLORATION AND LABORATORY TESTING Subsurface conditions were explored on April 17, 2003 by drilling two borings. The boring location were chosen to provide subsurface information at the major structure areas. The boring locations are shown on PLATE 3. The borinq were drilled with Mobile B-29 and Minuteman Flight Auger. Our soil engineer logged the boring and obtained bulk and relatively undisturbed drive samples for visual classification and subsequent laboratory testing. Drive samples were obtained with the Spraque and Henwood(S&H) split barrel sampler ( 2- inch I.D.) equipped with brass liner tubes. The samplers were driven with a 140-pound hammer falling 30- inches. Standard penetration test N-values obtained with the SPT sampler and approximate "Equivalent" N-value obtained with the S&H split-barrel sampler. Results are shown on the boring logs in PLATE 4. The soils encountered were described in accordance with the Unified Soils Classification System outlined in PLATE A1. 2 J. YANG AND ASSOCIATES LOCATION MAP PLATE 1 Project No. J03-1084 III. GEOTECHNICAL EVALUATION AND DISCUSSION A. Assessment of Seismic Hazards This site could be affected by an earthquake with its epicenter of the active faults in the Bay Area. At present, it is not possible to predict when or where movement will occur on these faults. It must be assumed, however, that movement along one or more of these faults will result in a moderate earthquake during the lifetime of any improvements at this site. Three active fault systems are known to exist within a vicinity of the site. The approximate location of these faults are as shown on PLATE lA. In the event of an earthquake, seismic risk to a structure will depend on the distance of the structure from the epicenter and source fault, the character and magnitude of the earthquake, the groundwater and soil conditions underlying the structure and its immediate vicinity, and the nature of the construction. The potential seismic hazards in the tests area are the affects of ground shaking resulting from earthquakes on nearby faults. Regional subsidence or uplift caused by a differential vertical movement along a fault takes place over large areas. In the event of such movement on the San Andreas Fault, the site would probably respond as a unit, resulting damage from this phenomenon is unlikely. Structural damage due to ground shaking is caused by the transmission of earthquake vibrations from the ground into a structure. The variables which determine the extent of damage are: the characteristics of the underlying earth materials, the design of the structure, the quality of materials and workmanship used in construction, the location and magnitude 3 J. YANG AND ASSOCIATES Project No. J03-1084 of the earthquake, and the duration and intensity of shaking. The most destructive effects of an earthquake are usually seen where the ground is unstable and the structures are poorly designed and constructed. Preliminary estimates of ground response characteristics at this site indicate that high accelerations can be expected during a moderate to major earthquake on the San Andreas Fault or a major earthquake on the Hayward fault or Canada Faults. Any of these events could cause strong ground shaking at this site. The duration of shaking and the frequency components of the vibrational waves will depend upon the magnitude and location of the earthquake. Structures should be designed to accommodate earthquake vibrations. If quality design and construction criteria are met, as set forth in the latest edition of the Uniform Building Code. B Site Geologic and Site Stabilitv The natural slopes on and near the site are relatively flat and show generally good site stability. In accordance with Geotechnical Hazards Synthesis Map(12/76) San Mateo County (Hazard Area Zone 8) that geologic materials are Santa Clara Formation. the Santa clara formation is principally a coarse-grained, fluvial deposit of conglomerate, sandstone, and claystone. these members of Purisima formationvary in composition from fine grained sandstone, silty mudstone ans procellaneous shale. The near-surface soils at the site are cohesive and are relatively resistant to erosion. However, clay material may be exposed locally, and fill may be composed of granular material. The granular materia� would be susceptible to erosion in unprotected. Additionally, the cohesive material could erode if grounds are left unplanted and subjected to fast flowing runoff. Recommendations are presented in this report which are intended to mitigate problems associated with erosion. ►� J. YANG AND ASSOCIATES Project No. J03-1084 C. SUBSURFACE SOIL CONDITIONS Based upon examination of the exploratory boring (See PLATE 4: Boring Logs). materials encountered in the two borings, at locations shown on PLATE 3. The subsurface soils consist generally of well consolidated clay and well consolidated silty clay layers. These materials generally grade from dense in relative density near the ground surface and hard at below 15 feet to greater depths. Our observation of the soil on the core samples indicated that the materials encountered in the two exploratory boring are generally two different layers with the materials observed on the core samples. Groundwater was not encountered at the time of our investigation at average depth of 15 feet. Detailed descriptions of materials encountered in each of the test boring are presented on the logs in Plate 4. Changes in the condition of the property may occur with the passage of time due to natural processes and on the subject site of adjacent properties. Thus, the drilled boring logs and related information depict subsurface conditions only at the locations indicated and on the particular date designated on the logs. Soil conditions at other locations may differ from conditions at these locations. 5 J. YANG AND ASSOCIATES �u �� s. ��a�ow�, s�ry.Y PLATE 1A� 7.S•minu�e quadranjlq u (ndiated Pho�oiariston as of 1971 ,'• • T��,•'�� . ►.�A�*�`!:�y ' � ��1��-��j s..:�,:�J,��. _.� 0 Project No. J03-1084 IV. CONCLUSIONS AND RECOMMENDATIONS The following conclusions and recommendations are based on the investigation and evaluations described in this report. The recommendations and specifications presented herein should be incorporated into the project plans and documents during design and construction. A. General Conclusions 1. The site is considered suitable from a geotechnical aspect for the proposed a family dwelling houses. 2. There were no soil or geologic conditions encountered during the investigation of the site which would preclude the planned construction. 3. The site, as is all the San Francisco Region, is in a seismically active area. Ground shaking is expected to have the following characteristics at the site and parameters are recommended: a. Seismic zone factor (Z) = 0.4 b. Seismic coefficient (Ca)= 0.45Na c. Seismic coefficient (Cv)= 0.64Nv d. Soil profile type = Sd e. Near-Source factor (Na)= 1.5, (Nv)=2.0 f. Seismic source type= A 4. The potentials for the secondary seismic effects of liquefaction is considered to be low at the site. 5. The potential for seismically-induced landsliding to occur is not considered at this site. 6. The recommendations in this report are based on the assumption grading will minimal. When final development plans and detailed grading plans are available, the conclusions and recommendations of this report should be reviewed and modified if necessary, to suit those plans. L J. YANG AND ASSOCIATES Project No. J03-1084 Site Preparation and Gradina 7. All grading operations associated with the planned development should be carried out as described in the following paragraphs. 8. Remove all organically contaminated soil, root systems and loose or soft soil in the areas of the planned development. Buried structures such as pipelines, other underground facilities should be removed from the areas of planned development. 9. Al1 compaction requirements are based on maximum dry densities and optimum moisture determined by ASTM Test Procedure D1557-90. 10. After stripping, areas to receive fill should be stripped to firm natural ground, scarified, moisture-conditioned to 3 to 5% above optimum moisture content, and compacted to at least 90% relative compaction. If soils are too wet, considerable drying time and discing may be required to reduce their moisture content to near optimum. Where cut natural ground is exposed beneath slabs-on-grade, the soil should be scarified to a depth of 5 inches, moisture conditioned as above, and compacted between 90% to 95% relative compaction. 11. Existing natural dark clay top soils may not be used as compacted fill in building and street areas, provided it is free of organic or other deleterious material. All fill should be compacted to at least 90% relative compaction at moisture contents 3 to 5% above optimum. The upper 24 inches of fill within pavement right-of-way should be compacted to at least 95% relative compaction. 7 J. YANG AND ASSOCIATES 0 Project No. J03-1084 12. Import fill, if used, should be approved by the Soil Engineer, and should have soil properties equivalent to or better than the natural soil. Import fill should not contain rocks larger than 4 inches in diameter. Surface and Subsurface Drainaqe 13. All grading at the site should be done in such a manner as to prevent ponding of water during or after construction. Positive surface drainage should be provided adjacent to any structures and pavements such that all surface waters are directed away from the foundations. Water should be directed into drop inlets and closed pipes that lead to suitable discharge facilities. Rainwater collected on the roof of the building should be transported through gutters, downspouts and closed pipes to suitable discharge facilities. In general, the soils at the site are cohesive and are not prone to erosion. 14. If there are any swales or draws which will be filled should be provided with subdrains to collect and discharge and subsurface seepage flow. Typically, subdrains will be perforated plastic pipe surrounded with select import filter material. The subdrains should be connected at their low points to a storm drainage system or to other approved discharge points. Subdrain outlets should be protected from erosion and siltation and be noted on "as-built" plans by the project Civil Engineer for future reference. Foundations 15. Top 2 ft. of soil is dark clay which is potential expansive. The proposed builcling structures should be founded on the firm soil. Recommendation for pier and grade beams are presented in this report. 8 J. YANG AND ASSOCIATES , Project No. J03-1084 16. The following general foundation type may be used at this site. Final selection of appropriate foundation systems will depend on the building structural engineer's preference within this report. Drilled Cast-In-Place Concrete Piers and Grade Beams The diameter of the piers should be a minimum of 16 inches and a minimum depth of 13 feet from bottom of the grade beam. The actual depths of piers will be determined at the time of drilling by soil engineer. The piers for these foundation systems should be transit structural loads to the subsurface soils. The drilled piers will derive their load carrying capacity from peripheral skin friction between the pier shaft and the surrounding soil. An allowable skin friction value of 500 pounds per square foot (psf ) of embedment may be used for design purposes for combined dead plus live loads. This value is applicable to both downward and for uplift resistance. Friction resistance in the upper portion of the pier within 18 inches of the ground surface should be neglected when determining the load carrying capacity of the piers. The pier should be reinforced their entire length and spaced at least three pier diameters. 7. If retaining walls are required as part of the building, the design criteria recommended for the building foundations are to be used. A combination of spread footings with key or pier foundation system may be combined for retaining wall footings. The retaining wall should be designed to resist lateral pressures exerted f�-om a media having an equivalent fluid weight as follows: Gradient Equivalent Passive Coefficient Angle of of Back Fluid Weight Resistance of friction Internal glope pcf pcf Friction Flat 50 350 0.25 30 2: 1 65 350 0.25 30 �'7 J. YANG AND ASSOCIATES Project No. J02-1040 Drainage behind retaining walls should consist of a 4-inch diameter perforated pipe surrounded by drain rock material (1/2inch to 1 inch in size). In addition, restrained retaining walls should be designed to resist an additional uniform pressure of 100 psf for the entire height of the wall. Concrete Slab-on-Grade Floors All concrete slab-on-grade should be supported on a minimum of 6 inches of Class 2 aggregate base. Slab subgrades should be rolled smooth prior to slab construction to provide a uniformly dense non-yielding surface. The class 2 aggregates should be compacted with a vibratory roller as per compaction requirements. Two inches of wetted sand should be placed over the membrane to minimize puncture and facilitate curing of the concrete. Aggregate should conform to the grading and quality requirements shown in the latest CALTRANS-'92 Standard Specification Section 26-1.02B. At the option of the contractor, the grading for either the 1-1/2 inch maximum or 3/4 inch shall be used. The subgrade should be compacted to at least 95% of relative compaction (ASTM 1557-90) Moisture vapor is likely to condense on the under side of slab-on-grade floors. If the moisture vapor is desirable, a synthetic membrane can be placed over the capillary break. infiltration of surface water. The perforated pipe along the base of the wall should be placed with the perforations down and should have a minimum 2 percent slope to drain by gravity to a suitable discharge location. Clean-out pipes that extend to the ground surface should be provided at every bends to allow for cleaning, should the pipe become clogged. 10 J. YANG AND ASSOCIATES Project No. J03-1084 Drainaae All ground surfaces, including pavements and sidewalks, should slope away from the structures at a gradient of at least 2 percent. Surface runoff should be controlled by a system of swales and catch basins, and then conveyed off the property to suitable discharge facility. Surface water should not be allowed to pond on the site. In addition, roof downspouts should be connected to closed collector pipes which discharge into the storm water system or onto paved parking areas or dispose through lined ditch. Flexible Pavement Thicknesses Based on an assumed R-value of 20 (typical clayey sand and clay mixtures), Assumed Traffic Indexes (T. I. ) and the CALTRANS design procedure for asphaltic concrete pavement, we recommend the following preliminary asphaltic concrete pavement thicknesses: Thickness (inches) Asphaltic Class 2 Location T.I. Concrete ActctregateBase* Automobile 4 2 5 Parking Driveways and 5 3 6 Service Areas R-Value -70 minimum the subgrade soil may vary in quality and contain local areas of low shear strengths. We should observe the completed subgrade to check that the preliminary pavement design is applicable. Subgrade soils to receive pavement should be rolled to provide a smooth, unyielding 11 J. YANG AND ASSOCIATES 0 Project No. J03-1084 Surface compacted to at least 95% relative compaction. On site subgrade soils should be maintained in a moist condition until covered the completed pavement section. The Class 2 Aggregate Base should be placed in a manner to prevent segregation, uniformly moisture conditioned to near optimum and compacted to at least 95% relative compaction with a smooth and unyielding surface. Trench Backfill 18. Underground utility trenches may be backfilled with on- site brown silty clay soils, provided they are moisture- conditioned to near optimum and are not in "chunks". Bedding and initial backfilling should be done in accordance with local requirements and specifications. Subsequent backfilling should be done in accordance with local requirements and specifications. Subsequent backfill (generally one foot and higher above the utility) should be placed in layers and mechanically compacted as follows: Trench Location Natural ground, outside street and lot areas. Lot areas and streets, below upper 24 inches. Street areas, upper 24 inches. 12 Minimum Relative Com�action 85% 90% 95% J. YANG AND ASSOCIATES Project No. J03-1084 Observation and Testina 19. All work connected with site grading, drainage and erosion control should be observed and tested by the Soil Engineer and Engineering Geologist. The purpose of these services will be to confirm that the conditions exposed during grading are as anticipated and provide supplemental recommendations if required; and to determine that the site work is being done in general conformance with the recommendations of this report and the City of Burlingame requirements. Additional Soil Engineerina Service 20. We should review the final design and specifications in order that earthwork and foundation recommendations may be properly interpreted and implemented in the design and specifications. We should provide engineering services during site preparation, grading, foundation and pavement construction phases of the work. This would allow us to observe compliance with the design concepts, specifications and to allow design changes in the event that surface conditions differ from those anticipated prior to the start of construction. 13 J. YANG AND ASSOCIATES Project No. J03-1084 V PLAN REVIEW CONSTRUCTION OBSERVATION AND TESTING We should be retained to review the earthwork and foundation plans and specifications for conformance with the intent of our recommendations. The review would enable us to modify our recommendations if final design conditions are not as we now understand them to be. During construction, we should observe and test the earthwork and foundation installation. As needed during construction, we should be retained to consult on geotechnical questions, construction problems, and unanticipated conditions. This will allow us to develop supplemental recommendations as appropriate for the actual soil conditions encountered and the specific construction techniques employed by contractor. 14 J. YANG AND ASSOCIATES 0 Project No. J03-1084 VI GUIDELINES FOR REQUIRED SERVICES The following list of services are the services required and must be provided by Yang and Associates, during the project development. These services are presented in check list format as a convenience to those entrusted with their implementation. The items listed are included in the body of the report in detail. This list is intended only as an outlined of the required services and does not replace specific recommendations and, therefore, must be used with reference to the total report. The importance of careful adherence to the report recommendations cannot be overemphasized. It should be noted, however, that this report is issued with the understanding that each step of the project development will be performed under the direct observation of Yang and Associates. The use of this report by others presumes that they have verified all information and assume full responsibility for the total project. 15 J. YANG AND ASSOCIATES Project No. J03-1084 ITEM DESCRIPTION REQUIRED NOT REQUIRED 1. Provide foundation design parameters X 2. Review grading plans & specifications X 3. Review foundation plans & specs. X 4. Observe & provide demolition recommendation X 5. Observe & provide site stripping X recommendations 6. Observe and provide recommendations on moisture conditioning, removal and/or X precompaction of unsuitable existing soils 7. Observe and provide recommendations on X installation of subdrain facilities 8. Observe and provide testing services on X fill areas and/or imported fill materials 9. Review as-graded plans and provide additional X foundation recommendations, if necessary 10. Observe and provide compaction tests on sanitary sewers, storm drain, water lines X and PG&E trenches 11. Observe foundation excavations and provide supplemental recommendations, if necessary, X prior to placing concrete 12. Observe and provide moisture conditioning recommendations for foundation areas prior X to placing concrete 13. Provide design parameters for retaining walls X 14. Provide geologic observations and recommendations for keyway excavations and X cut slopes during grading 15. Excavate and recompact all geologic trenches X and/or test pits. 16 J. YANG AND ASSOCIATES 0 Project No. J03-1084 VII. LIMITATIONS AND UNIFORMITY OF CONDITIONS A. The recommendations of this report are based upon the assumption that the soil conditions do not deviate from those disclosed in the borings and test pits. If and variations or undesirable conditions are encountered during construction, or if the actual construction will differ from that planned at the present time, J. Yang and Associates should be notified so that supplemental recommendations can be given. B. This report is issued the understanding that it is responsibility of the owner or of his representatives to ensure that the information and recommendations contained herein are called to the attention of the other members of the design team (architect and engineers) for the project and are incorporated into the plans, and that the necessary steps are taken to see that the contractors and subcontractors carry out such recommendations in the field. C. The findings of this report are valid as of the present date. However, changes in the conditions can occur with the passage of time, whether they be due to natural processes or to the works of man, on this or adjacent properties. In addition, changes in applicable or appropriate standards may occur, whether they result from legislation or the broadening of knowledge. Accordingly, the findings of this report may be invalidated, wholly or in part, by changes outside of our control. Therefore, this report is subject to review by J. Yang and Associates after a period of three(3) years has elapsed from date of issuance of this report. D. The body of the report specifically recommends that J. Yang and Associates be provided the opportunity for general review of the project plans and specifications, and that J. Yang and Associates be retained to provide observation and testing services during construction. The validity of this report assumes that J. Yang and Associates will be retained to provide these services. 17 J. YANG AND ASSOCIATES Project No. J03-1084 E. This report was prepared at your request for our services, and in accordance with the currently accepted geotechnical engineering practice. No warranty based on the contents of this report is intended, and none shall be inferred from the statements or opinions expressed herein. 18 J. YANG AND ASSOCIATES. �PPENDIX AA �7N1 `UJN3 Y N,M934 S W awsr�O+��W �P'Y!I'?!�9Rl�nd��P d� `HYVdJI�tI'Rltlfi � : , N '3AV 2I3AftO�I�IdA I9Zi p " ` � e� �uamsaa nkaH , ' �A72af�R' R �� O � z � � �o �� s� g � � " �t ! � � �l�� -, r � � �� i_� �LJ �— �� , �� W� � :, W � Z � W � >a 4 � � w � s .� � � 7 � a. �.' y �� ,i � Wi �� QI J'. � i C7 z �: OM '' W w O : z Q ': 1�1 : E"� ! �i 'i Vi O; � �•d i_u�a-c+,c rnca� •�9u� u�tsart nu� eQ+.:nr cn rr �du � � ' MAJOR DIVISIONS TYPICAL NAMES GW ' ��"'�' wEll-GRADED GRAVELS. GRAVEL�SAND •'r::'�.:.:. MIXTURES W CLEAN GRAVEIS WITH • W GRAVELS LITTIE OR NO FINES GP .. p�q�Y GRADED GP.AVELS. GRAVEL�SAND .'.:.�.;•:. � �::•.'•.�; MIxTUF�ES J N MORE THAN HALF � Z COARSE FRACTION G►� $qND SRLTVMIXTUPREOS `Y GRADEO G�VEL• � IS IARGER THAN Z No. 4 S�EVE S�ZE GRAVELS W�TH OVER w� t2°/. fINES GC C�p,YEY GRAVELS. POORLY GRADED G�VEL • Z Q SAND�CLAY MIXTURES �w � ¢ ' •'• � g sw �� WEII- GRADED SANUS. GRAVELLY SANDS 1 N CIEAN SAN05 W�TH �� Q LITTLE OA NO FINES � � SANDS Sp '�' �' pppRLY G�DED SANOS. GRAVELLY SANDS z �Z • • . Q = MORE TNAN HALF ��- CAARSE FRACTION SM ••• SILTY SANDS. POOFiLY GRADED ' U w �S SMALLER THAN • SAND•SIIT MIXTURES p NO 4 SIEVE SIZE $ANDS WITH OVER • • � 12% FINES ''' C�qYE� SANDS. POORIY GRADEO SC � • • S,qND•CLAY MIXTURES . . • INORGANIC SILTS AND VERY FINE SANDS. ML FOCK F�OUA. SILTY OR CLAYEY FINE SANDS. OR CIAYEY SILTS WITH SLIGHT PLASTICITY J W SILTS AND CLAYS INORGANIC CIAY$ OF lOW TO �aEI��UM CL PLASTICITY, GFU1VElLY CLAYS. SANDY CLAYS. J SILTY CLAYS. LEAN CLAYS N�`j LIOUID LIMIT 50% OR IESS �- ( �( ORGANIC CLAYS AN� ORGANtC SIITY CLPYS W LL $ • �� ( OF LOW PLASiICITY Za`" IIII Z O �NORGANIC SILTS. MICACEOUS OR Q Z Z MH DIATOMACEOUS FINE SANDY OR SILTY � a Z SpIIS. ELASTIC SILTS � C7�= wQ� SILTS AND CLAYS CH INORGANIC CIAYS OF HIGH PIASTICITY. FAT Z � CIAYS LIQUID LIMIT GREATEA THAN 50°/. � �i ORGANIC CLAYS OF MEDIUM TO HIGH OH y,/� p�qSTICITY. ORGANIC SIUS / HIGHLY ORGANIC SOILS P� PEAT AND OTHER HIGHLY ORGANIC SOILS UNIFIED SOIL CLASSIFICATION SYSTEM ti : t Perm — Permeability Consol — Consolidation �� — Liquid Limit (%) PI — Plastic Index (%) GS — Specilic Gravily MA — Particle Size Analysis � — "Undislurbed" Sample � — Bulk or Classilication Sample -200 — % Finer No. 200 Sieve Consrslency - ojsoil Very soft Soft Mcdium Stiff Very stifl` Hard N (Srondord ptntlralion r�sisroncr) Q-2 2-4 4-8 8-15 15-30 36 Squarc Joolrngs Al1or+•ablt brnring prtssure 0.00-0.30 0.30-0.60 0.60/�-1.20 1.2\T2.4U 2.4ad.80 4.80 Continuous joorrngs rons�sq Jt 0.22 o.u-o.as 0.4(y5�-0.9p0 Q.IIT � .00 1.8a3.60 3.60= KEY TO TEST DATA SOIL CLASSIFICATION CHA PLATE 3 KEY TO TEST DATA A 1 • I T � ' pPAWN J09 NUMBER AVPROVEO DATE AEVISED M E ,, PROJECT 126i vancouver Ave BORlNG NO. Burlingame, CA EB - 1 BORING SUPERVISOR J. Yang E��NG DATE OF BORING � B29 5 Solid Stem 4-r7-03 HAMMER WEIGFCf t 40u/30.' drop _ ' v LL Q Z V � W � a SURFACE ELEVATlON � . � � 8 � � o . „ cr �n � GROUND WATER EL�1/ATION ATD � ?`? " Z a'i o Z � �- � � cn DESCRIPTION� OF MATERIALS o�� o m o � Silty clay, brown, mois�t. Silty clay/clayey sand, dark brown, moist. . Mottled silty sand/clayey sand mix, moist, �hard. � Bottom of hole �a �� w O� � � �E51 I2" � 30 I 100 I 18 I 2.5ksf EB1 10 2" 40 100 19 3:5ksf EB1 17 1.5 40 -- -- SPT 4tsf .�oe wo. J. Y�lNG AND ASSOCIATES ��NO' J03-1084 � Consulting Engineers PLATE 4 , ., � PROJECT 1261 vancouver Ave BORIN2G NO. Burlingame, CA BORING SUPERVISOR J. Y ang E��G DATE OF BORlNG . B.29 5 Solid Stem 4-Y7-03 HAMMER WEIGHT 14o#/30' drop �_ ' v LL W a U � SURFACE ELEVATION � �" a � � � v�i�� 8 �" �.: GROUND WATER ELE�/ATiOf�t ATD p Z z. w " a z u�. o ,�`,� � �� . � � � �3 � � �w o� DESCRIPTION� OF MATERIALS �� o m o � �� 0 Siltv clay, brown, moist. Silty sand/clayey sand, dark brown, moist. � E52I2" I 35 I 102 I 19 � I2.5ksf 102I 2" I 45 I 105 I 20 I3,5ksf Mottled silty sand, brown, moist., Bottam of hole 0 .�oB No. J. YANG AND ASSOCIATES � ��NO' J03-1084 Consulting Eng/neers PLATE 4