The URL can be used to link to this page

Home My WebLink AboutReport Geothecnical Exploration1 GFA INTERNATIONAL FLORIDA'S LEADING ENGINEERING SOURCE Report of Geotechnical Exploration Proposed Two -Story Residence Lot 1299 Nettles Island St. Lucie County, Florida June 15, 2015 GFA Project No.: 15-1239.00 For: JWN Construction q r ry h xUM. YS SA $^ ..�cSZ 90R7tl ii f3 •^k"f iiR t�3gx2 TSQ q YaaaGrd r,��sa❑ gsaar�aa c��mq �GIX�g3Y Y96 ?�DAe�l56 ,ssaz� xsvm�csggm. 5qn Six qS�q ..GO q. ..ggg1(R i1 N.• '�' Yl.. pS5 S88)tld 9'ns [lEUAa. J. aoagac gave �ara�mP€;� q �aqs, Florida's Leading Engineering Source Environmental - Geotechnical • Construction Materials Testing • Threshold and Special Inspections - Plan Review & Code Compliance December 10, 2013 JWN Construction Attn: James Newman 1701 SE Carvalho Street Port St. Lucie, Florida 34982 Site: Proposed Two -Story Residence Lot 1299 Nettles Island St. Lucie County, Florida GFA Project # 15-1239.00 Dear Mr. Newman: GFA International, Inc. (GFA) has completed the subsurface exploration and geotechnical engineering evaluation for the above -referenced project in accordance with the geotechnical and engineering service agreement for this project. The scope of services was completed in accordance with our _Geotechnical Engineering Proposal (15-1239.00) dated June 5, 2015, planned in conjunction with and authorized by you. EXECUTIVE SUMMARY The purpose of our subsurface exploration was to classify the nature of the subsurface soils and general geomorphic conditions and evaluate their impact upon the proposed construction. This report contains the results of our subsurface exploration at the site and our engineering interpretations of these, with respect to the project characteristics described to us including providing recommendations for site preparation and the design of the foundation system. Based on conversations with the client, the project consists of demolishing and removing an existing modular residence and then constructing a two-story residence. GFA was informed that a pile foundation is required due to flood zone requirements (to be determined by others). To achieve the ground floor flood elevation, the ground level slab may have to be elevated a few feet above existing grade, possibly creating a crawl space. We have not received any information regarding structural loads. For the foundation recommendations presented in this report we assumed the maximum column load will be 60 kips and the maximum wall loading will be 4 kips per linear foot. GFA estimates the site is at or near final grade. The recommendations provided herein -are based upon the above considerations. If the project description has been revised, please inform GFA International so that we may review our recommendations with respect to any modifications. A total of one (1) standard penetration test (SPT) boring to a depth of approximately forty (40) feet, and one (1) Auger Boring (AB) to approximately ten (10) feet, below ground surface (BGS) were completed for this study. The subsurface soil conditions encountered at this site generally consist of loose to medium dense sand (SP) to 9 feet, very loose/soft sand and silt and clay (CL,ML) from 9 to 12 feet, 521 NW Enterprise Drive • Port St. Lucie, Florida 34986 • (772) 924-3575 • (772) 924.3580 (fax) • www.teamgfa.com OFFICES THROUGHOUT FLORIDA Proposed Two -Story Residence Lot 1299 Nettles Island, St. Lucie County, FL GFA Project No. 15-1239.00 Geotechnical Report June 15, 2015 Page 2 of 10 medium dense sand (SP) from 12 to 28'/z feet with silt and clay layers (CL,ML), and then medium dense sand with occasional little cemented sand (SP) to the boring termination depths. Please refer to Appendix D - Record of Test Borings for a detailed account of each boring. GFA was informed that a pile foundation is required due to flood zone requirements (to be determined by others). GFA recommends that the proposed residence (including floor slab if required) be supported using a deep foundation system consisting of augered cast -in -place (ACIP) piles. Based on our analysis, GFA has estimated that a 14-inch-diameter ACIP pile installed to a depth of 32 feet below existing grade (grade even with the adjacent roadway) can provide a maximum allowable axial compressive capacity of 30 tons and a maximum tension capacity of 10 tons. Analysis of the foundation performance under hurricane conditions or other storm events, including the effects of loss of soil support due to scour or other forces, is not within the scope of this report, and the recommendations are valid only for normal conditions. Additional analysis and options for foundation systems with scour conditions or other scenarios can be performed if requested. For the existing seawall and/or retaining wall, they must have the structural integrity to withstand the loadings imposed by the new residence or other structures and construction methods. Evaluation and design of the walls are the responsibility of the structural engineer, specialty engineer, contractor, or others. Evaluation of walls are not within our scope of work. We appreciate the opportunity to be of service to you on this project and look forward to a continued association. Please do not hesitate to contact us if you have any questions or comments, or if we may further assist you as your plans proceed. Res qb-Pully Suboo l GF�,�'► 1 fiorfa11, r" F$e, a° Certificate tAization Number 4930 1 ' n% ' ° �Uj:�N 2° i�a1�IV. ldoler, P.E. e �Qr 1 a o Si?yitechnicaJ.Eng er Flo rf iNs#F E n I ,�$0675 °°°rrrri Copies: 2, Addressee D id Alker Project Manager C,FA Proposed Two -Story Residence Geotechnical Report Lot 1299 Nettles Island, St. Lucie County, FL June 15, 2015 GFA Project No. 15-1239.00 Page 3 of 10 TABLE OF CONTENTS 1.0 INTRODUCTION.................................................................................................................4 1.1 Scope of Services.............................................................................................................4 1.2 Project Description...........................................................................................................4 2.0 OBSERVATIONS.................................................................................................................4 2.1 Site Inspection.................................................................................................................4 2.2 Field Exploration..............................................................................................................5 2.3 Laboratory Analysis..........................................................................................................5 2.4 Geomorphic Conditions....................................................................................................5 2.5 Hydrogeological Conditions..............................................................................................6 3.0 ENGINEERING EVALUATION AND RECOMMENDATIONS..............................................6 3.1 Foundation Recommendations.........................................................................................6 3.2 Pile Installation.................................................................................................................8 3.3 Vibration Monitoring..........................................................................................................8 3.4 Ground Floor Slab............................................................................................................8 3.5 General Site Preparation..................................................................................................9 3.6 Excavation Conditions......................................................................................................9 4.0 REPORT LIMITATIONS.....................................................................................................10 5.0 BASIS FOR RECOMMENDATIONS..................................................................................10 Appendix A - Vicinity Map Appendix B - Test Location Plan Appendix C - Notes Related to Borings Appendix D - Record of Test Borings Appendix E - Discussion of Soil Groups C,FA Proposed Two -Story Residence Geotechnical Report Lot 1299 Nettles Island, St. Lucie County, FL June 15, 2015 GFA Project No. 15-1239.00 Page 4 of 10 1.0 INTRODUCTION 1.1 Scope of Services The objective of our geotechnical services was to collect subsurface data for the subject project, summarize the test results, and discuss any apparent site conditions that may have geotechnical significance for building construction. The following scope of services are provided within this report: 1. Prepare records of the soil boring logs depicting the subsurface soil conditions encountered during our field exploration. 2. Conduct a review of each soil sample obtained during our field exploration for classification and additional testing if necessary. 3. Analyze the existing soil conditions found during our exploration with respect to foundation support for the proposed structure. 4. Provide recommendations with respect to foundation support of the structure, including allowable soil -bearing capacity, bearing elevations, and foundation design parameters. 5. Provide criteria and site preparation procedures to prepare the site for the proposed construction. 1.2 Project Description Based on conversations with the client, the project consists of demolishing and removing an existing modular residence and then constructing a two-story residence. GFA was informed that a pile foundation is required due to flood zone requirements (to be determined by others). To achieve the ground floor flood elevation, the ground level slab may have to be elevated a few feet above existing grade, possibly creating a crawl space. We have not received any information regarding structural loads. For the foundation recommendations presented in this report we assumed the maximum column load will be 60 kips and the maximum wall loading will be 4 kips per linear foot. GFA estimates the site is at or near final grade. The recommendations provided herein are based upon the above considerations. If the project description has been revised, please inform GFA International so that we may review our recommendations with respect to any modifications. 2.0 OBSERVATIONS 2.1 Site Inspection The project site was within a subdivision and a one-story modular residence occupied the location of the proposed new two-story residence. The grade at the site was estimated to be even with the adjacent road at the time of drilling. Residential structures were adjacent to the (I FA i Proposed Two -Story Residence Geotechnical Report Lot 1299 Nettles Island, St. Lucie County, FL June 15, 2015 GFA Project No. 15-1239.00 Page 5 of 10 property. The property is located on an island within the Intracoastal Waterway (Indian River). A seawall bordered a portion of the south side of the property. 2.2 Field Exploration A total of one (1) standard penetration test (SPT) boring to a depth of approximately forty (40) feet, and one (1.) Auger Boring (AB) to approximately ten (10) feet, below ground surface (BGS) were completed for this study. The upper 4 feet of the SPT boring were drilled with a hand auger in order to avoid damaging utilities. Hand Cone Penetrometer (HCP) tests were conducted at one -foot intervals in the auger boring. The HCP test, in conjunction with information about the soil type, is empirically correlated to the relative density of subsurface soils. The locations of the borings performed are illustrated in Appendix B: "Test Location Plan". The Standard Penetration Test (SPT) and HCP methods were used as the investigative tools within the borings. SPT tests were performed in substantial accordance with ASTM Procedure D-1586, "Penetration Test and Split -Barrel Sampling of Soils" and the auger boring in substantial accordance with ASTM Procedure D-1452, "Practice for Soil Investigation and Sampling by Auger Borings". The SPT test procedure consists of driving a 1.4-inch I.D. split - tube sampler into the soil profile using a 140-pound hammer falling 30 inches. The number of blows per foot, for the second and third 6-inch increment, is an indication of soil strength. The soil samples recovered from the soil borings were visually classified and their stratification is illustrated in Appendix D: "Record of Test Borings". It should be noted that soil conditions might vary between the strata interfaces, which are shown. The soil boring data reflect information from a specific test location only. Site specific survey staking for the test locations was not provided for our field exploration. The indicated depth and location of each test was approximated based upon existing grade and estimated distances and relationships to obvious landmarks. The boring depths were confined to the zone of soil likely to be stressed by the proposed construction and knowledge of vicinity soils. 2.3 Laboratory Analysis Soil samples recovered from our field exploration were returned to our laboratory where they were visually examined in general accordance with ASTM D-2488. Samples were evaluated to obtain an accurate understanding of the soil properties and site geomorphic conditions. After a thorough visual examination of the recovered site soils, no laboratory testing was deemed necessary. Bag samples of the soil encountered during our field exploration will be held in our laboratory for your inspection for 30 days and then discarded unless we are notified otherwise in writing. The recovered samples were not examined, either visually or analytically, for chemical composition or environmental hazards. GFA would be pleased to perform these services for an additional fee, if required. 2.4 Geomorphic Conditions The geology of the site as mapped on the USDA Soil Survey website consists of Arents, 0 to 5 percent slopes (4). These are sandy soils and organic soils are not indicated. However, these are areas in which the soils have been generally altered by grading, shaping, and covered with fill and therefore the soils can be variable. It should be noted that the Soil Survey generally GFA �1 Proposed Two -Story Residence Lot 1299 Nettles Island, St. Lucie County, FL GFA Project No. 15-1239.00 Geotechnical Report June 15, 2015 Page 6 of 10 extends to a maximum depth of 80 inches (approximately 63/ feet) below ground surface and is not indicative of deeper soil conditions. Boring logs derived from our field exploration are presented in Appendix D: "Record of Test Borings". The boring logs depict the observed soils in graphic detail. The Standard Penetration Test borings indicate the penetration resistance, or N-values, and the auger borings the HCP values logged, during the drilling and sampling activities. The classifications and descriptions shown on the logs are generally based upon visual characterizations of the recovered soil samples. All soil samples reviewed have been depicted and classified in general accordance with the Unified Soil Classification System, modified as necessary to describe typical Florida conditions. See Appendix E: "Discussion of Soil Groups", for a detailed description of various soil groups. The subsurface soil conditions encountered at this site generally consist of loose to medium dense sand (SP) to 9 feet, very loose/soft sand and silt and clay (CL,ML) from 9 to 12 feet, medium dense sand (SP) from 12 to 28'/2 feet with silt and clay layers (CL,ML), and then medium dense sand with occasional little cemented sand (SP) to the boring termination depths. Please refer to Appendix D - Record of Test Borings for a detailed account of each boring. 2.5 Hydrogeological Conditions On the dates of our field -exploration, the groundwater. table was encountered at depths ranging from approximately 4'/4 to 5'/2 feet below the existing ground surface. The groundwater table will fluctuate seasonally depending upon local rainfall and other site specific and/or local influences including the water levels in the nearby Intracoastal Waterway (Indian River) with tidal influences. No additional investigation was included in our scope of work in relation to the wet seasonal high groundwater table or -any existing well fields in the vicinity. Well fields may influence water table levels and cause significant fluctuations. If a more comprehensive water table analysis is necessary, please contact our office for additional guidance. 3.0 ENGINEERING EVALUATION AND RECOMMENDATIONS 3.1 Foundation Recommendations A foundation system for any structure must be designed to resist bearing capacity failures, have settlements that are tolerable, and resist the environmental forces that the foundation may be subjected to over the life of the structure. The soil bearing capacity is the soil's ability to support loads without plunging into the soil profile. Bearing capacity failures are analogous to shear failures in structural design and are usually sudden and catastrophic. The amount of settlement that a structure may tolerate is dependent on several factors including: uniformity of settlement, time rate of settlement, structural dimensions and properties of the materials. Generally, total or uniform settlement does not damage a structure but may affect drainage and utility connections. These can generally tolerate movements of several inches for building construction. In contrast, differential settlement affects a structure's frame and is limited by the structural flexibility. GFA Proposed Two -Story Residence Lot 1299 Nettles Island, St. Lucie County, FL GFA Project No. 15-1239.00 Geotechnical Report June 15, 2015 Page 7 of 10 GFA was informed that a pile foundation is required due to flood zone requirements (to be determined by others). GFA recommends that the proposed residence (including floor slab if required) be supported using a deep foundation to transfer the structural loads from the surface level to an underlying suitable bearing strata. At this time, GFA recommends the deep foundation to consist of augered cast -in -place piles (ACIP). ACIP pile installation procedures should be performed in accordance with the guidelines presented in the latest edition of the Deep Foundations Institute's Augered Cast -In -Place Pile Manual. The lateral capacity and pile top deflection were calculated using the commercially available L-pile 4.0 software. A summary of pile capacities for a 14-inch diameter ACIP piles is presented in the following table. Pile Recommendations For All Pile Supported Structures Maximum Nominal Pile Top Recommended Pile Pile Pile Pile Lateral Pile Elevation Pile Tip Lengths Compression Tension Capacity Recommended Diameter NGVD Elevation ft * Capacity Ca aci (Tons)** Grout Stren th 3 Tons (Free Head) 8 Tons 14" Unknown Unknown 32 30 Tons 10 Tons Fixed Head 5000 psi *Based on existing site grade. **For calculated pile top deflection of % inches at ground surface/top of pile elevation. The pile installation length is -based on installing the piles at site grade (grade even with the adjacent roadway) existing at time of drilling. If additional fill will be required to raise the site to achieve final grade, the piles will be longer according to the depth of fill added. GFA assumed that the piles will have a minimum of 1 % steel reinforcement for the analyses. Augercast piles should be reinforced over their entire length for tension capacity. The reinforcement shall be as designed by the Structural Engineer. If piles of lesser or greater capacities than those mentioned in the table above are required, GFA would be pleased to provide further recommendations upon request. The following additional notes are applicable to the pile design: • A 25% Increase in the pile capacity is permissible for temporary wind loads. • Structural stresses in the piles may impose a more severe limitation on the design capacity; therefore, we recommend the allowable stresses be verified for the selected pile section. • The pile reinforcement is sufficiently embedded in the pile cap so as to afford a fixed end connection. • The piles and pile caps are commonly surrounded by soil and can safely withstand a horizontal deflection on the order of/z inch. r� � � I Proposed Two -Story Residence Geotechnical Report Lot 1299 Nettles Island, St. Lucie County, FL June 15, 2015 GFA Project No. 15-1239.00 Page 8 of 10 3.2 Pile Installation Pile design and installation shall be in accordance with the applicable sections of the Florida Building Code and other applicable federal, state and local requirements. In addition, piles should be installed in accordance with the following: 1. Pile Length: The proposed 14-inch-diameter piles should be installed as determined by the inspecting Geotechnical Engineer. 2. Spacing - Piles installed in groups should be spaced at a center -to -center distance of not less than 3 pile diameters. 3. Plan Location - The center of the top of any pile at cut-off should be displaced laterally no more than 3 inches from the position shown on the plans. This applies to both single piles and piles installed in groups. 4. Vertical Alignment - The vertical alignment of the piling should not deviate from the plumb by more than 1/4 inch per foot of length. 5. Reinforcing Cage Positioning = The top of the reinforcing cages installed in the piling should not be more than 6 inches above and no more than 3 inches below the positions shown in the plans. The reinforcing cages should be positioned concentrically within the grouted pile shaft. The grout cover over longitudinal reinforcing bars should not be less than 3 inches. Reinforcing centralizers shall be placed at maximum spacing of 15 feet at the lower portion of the pile and at 5 feet from the cage's top. 6. Adjacent Piles - A minimum time period of 12 hours should be specified for the installation of piles located within 5 feet, center -to -center, of each other. 7. Grout Factor - The minimum acceptable grout factor (i.e. actual grout volume divided by theoretical grout volume) should be 1.2. 3.3 Vibration Monitoring The proposed construction will be within close proximity to residential structures and roadways that maybe susceptible to damage from vibration generated at the site. We recommend that during all aspects of construction, the bordering landmarks be monitored using a seismograph to determine the, extent of vibration absorption that these features will be subject to. The seismograph used to monitor at this site should have the capability to measure ground velocities along vertical; transverse, and longitudinal axes. The project structural engineer should establish allowable ground velocities that the bordering facilities can safely withstand without any damage. 3.4 Ground Floor Slab The ground floor should be structurally integrated with the pile cap foundation. Water vapor is likely to rise through the granular fill and condense beneath the base of the floor slab. If C,FA Proposed Two -Story Residence Geotechnical Report Lot 1299 Nettles Island, St. Lucie County, FL June 15, 2015 GFA Project No. 15-1239.00 Page 9 of 10 moisture entry into the floor slab is not desirable, an impermeable membrane should be installed at the slab bottom - subgrade interface. 3.5 General Site Preparation Initial site preparation should consist of performing stripping (removing surface vegetation, near surface roots, and other deleterious matter) and clearing operations. This should be done within, and to a distance of five (5) feet beyond, the perimeter of the proposed building footprint (including exterior isolated columns) if possible. Foundations and any below grade remains of any structures that are within the footprint of the new construction should be removed, and utility lines should be removed or properly abandoned so as to not affect structures. If the demolished residence had a pile foundation, GFA must be notified as the recommendations may change. The stripped areas should be proofrolled and compacted until the upper 2 feet of soil achieve a density of at least 95% of the modified Proctor maximum dry density (ASTM D 1557). Fill material may then be placed in the building pad as required. The fill material should be inorganic (classified as SP, SW, GP, GW, SP-SM, SW-SM, GW-GP, GP -GM) containing not more than 5 percent (by weight) organic materials. Fill materials with silt/clay-size soil fines in excess of 12% should not be used. Fill should be placed in lifts with a maximum lift thickness not exceeding 12-inches. Each lift should be compacted and tested prior to the placement of the next lift. Density tests should be performed within the fill at a frequency of not less than one test per 2,500 square feet per lift in the building areas, or a minimum of three (3) tests per lift, whichever is greater. Upon completion of production pile installation and pile cap construction, the pile caps should be backfilled in 6 to 8 inch thick lifts and compacted to at least 95% of the modified Proctor maximum dry density (ASTM D 1557). Using vibratory compaction equipment at this site may disturb adjacent structures. We recommend that you monitor nearby structures before and during proof -compaction operations. A representative of GFA International can monitor the vibration disturbance of adjacent structures. A proposal for vibration monitoring during compaction operations can be supplied upon request. 3.6 Excavation Conditions In Federal Register, Volume 54, No. 209 (October 1989), the United States Department of Labor, Occupational Safety and Health Administration (OSHA) amended its "Construction Standards for Excavations, 29 CFR, part 1926, Subpart P". This document was issued to better insure the safety of workmen entering trenches or excavations. It is mandated by this federal regulation that all excavations, whether they be utility trenches, basement excavations or footing excavations, be installed in accordance with the OSHA guidelines. It is our understanding that these regulations are being strictly enforced and if they are not closely followed, the owner and the contractor could be liable for substantial penalties. The contractor is solely responsible for designing and constructing stable, temporary excavations and should shore, slope, or bench the sides of the excavations as required to maintain stability of both the excavation sides and bottom. The contractor's responsible person, as defined in 29 CFR Part 1926, should evaluate the soil exposed in the excavations as part of C,FA Proposed Two -Story Residence Lot 1299 Nettles Island, St. Lucie County, FL GFA Project No. 15-1239.00 the contractor's safety procedures. In excavation depth, including utility trenc Geotechnical Report June 15, 2015 Page 10 of 10 h 4.0 REPORT LIMITATIONS This consulting report has been prepared for the exclusive use of the current project owners and other members of the design team for the Proposed Two -Story Residence located at Lot 1299 Nettles Island., St. Lucie County, Florida. This report has been prepared in accordance with generally accepted local geotechnical engineering practices; no other warranty is expressed or implied. The evaluation submitted in this report, is based in part upon the data collected during a field exploration, however, the nature and extent of variations throughout the subsurface profile may not become evident until the time of construction: If.variations then appear evident, it may be necessary to reevaluate information and professional opinions as provided in this report. In the event changes are made in the nature, design, or locations of the proposed structure, the evaluation and opinions contained in this report shall not be considered valid, unless the changes are reviewed and conclusions modified or verified in writing by GFA International. Analysis of the foundation performance under hurricane conditions or other storm events, including the effects of loss of soil support due to scour or other forces, is not within the scope of this report, and the recommendations are valid only for normal conditions. Additional analysis and options for foundation systems with scour conditions or other scenarios can be performed if requested. 5.0 BASIS FOR RECOMMENDATIONS The analysis and recommendations submitted in this report are based on the data obtained from the tests performed at the locations indicated on the attached figure in Appendix B. This report does not reflect any variations, which may occur between borings. While the borings are representative of the subsurface conditions at their respective locations and for their vertical reaches, local variations characteristic of the subsurface soils of the region are anticipated and may be encountered. The delineation between soil types shown on the soil logs is approximate and the description represents our interpretation of the subsurface conditions at the designated boring locations on the particular date drilled. Any third party reliance of our geotechnical report or parts thereof is strictly prohibited without the expressed written consent of GFA International. The applicable SPT methodology (AST M D-1586), CPT methodology (ASTM D-3441), and Auger Boring methodology (ASTM D-1452) used in performing our borings and sounding, and for determining penetration and cone resistance is specific to the sampling tools utilized and does not reflect the ease or difficulty to advance other tools or materials. Appendix A - Vicinity Map GF� Vicinity Map Proposed Two -Story Residence Lot 1299 Nettles Island St. Lucie County, FL GFA Project No. 15-1239.00 Appendix B - Test Location Plan Legend 'yT�ANRi1��p� Test Location Plan Proposed Two -Story Residence Lot 1299 Nettles Island St. Lucie County, FL GFA Project No. 15-1239.00 Approximate Standard Penetration Test (SPT) Boring & Auger Boring (AB) Locations Appendix C - Notes Related to Borings 60 NOTES RELATED TO RECORDS OF TEST BORING AND GENERALIZED SUBSURFACE PROFILE 1. Groundwater level was encountered and recorded (if shown) following the completion of the soil test boring on the date indicated. Fluctuations in groundwater levels are common; consult report text for a discussion. 2. The boring location was identified in the field by offsetting from existing reference marks and using a cloth tape and survey wheel. 3. The borehole was backfilled to site grade following boring completion, and patched with asphalt cold patch mix when pavement was encountered. 4. The Record of Test Boring represents our interpretation of field conditions based on engineering examination of the soil samples. 5. The Record of Test Boring is subject to the limitations, conclusions and recommendations presented in the Report text. 6. "Field Test Data" shown on the Record of Test Boring indicated as 11/6 refers to the Standard Penetration Test (SPT) and means 11 hammer blows drove the sampler 6 inches. SPT uses a 140-pound hammer falling 30 inches. 7. The N-value from the SPT is the sum of the hammer blows required to drive the sampler the second and third 6- inch increments. 8. The soil/rock strata interfaces shown on the Records of Test Boring are approximate and may vary from those shown. The soil/rock conditions shown on the Records of Test Boring refer to conditions at the specific location tested; soil/rock conditions may vary between test locations. 9. Relative density for sands/gravels and consistency for silts/clays are described as follows: SPT CPT SANDS/GRAVELS SPT CPT SILTS/CLAYS BLOWS/FOOT KG/CM RELATIVE DENSITY BLOWS/FOOT KG/CM- CONSISTENCY 0-4 0-16 Very loose 0-1 0-3 Very soft 5-10 17-40 Loose 2-4 4-6 Soft 11-30 41-120 Medium Dense 5-8 7-12 Firm 31-50 121-200 Dense 9-15 13-25 Stiff 50+ over 200 Very Dense 16-30 25-50 Very stiff >30 >50 Hard 10. Grain size descriptions areas follows: NAME SIZE LIMITS Boulder 12 Inches or more Cobbles 3 to 12 Inches Coarse Gravel 3/4 to 3 Inches Fine Gravel No. 4 sieve to N inch Coarse Sand No. 10 to No. 4 sieve Medium Sand No. 40 to No. 10 sieve Fine Sand No. 200 to No. 40 sieve Fines Smaller than No. 200 sieve 11. Definitions related to adjectives used in soil/rock descriptions: PROPORTION ADJECTIVE APPROXIMATE ROOT DIAMETER ADJECTIVE <5% Trace Less than 1/32" Fine roots 5% to 12% Little 1/32" to'/o" Small roots 12% to 30% Some Y" to l" Medium roots 30% to 50% And Greater than 1" Large roots Organic Soils: Soils containing vegetable tissue in various stages of decomposition that has a fibrous to amorphous texture, usually a dark brown to black color, and an organic odor. Organic Content <25%: Slightly to Highly Organic; 25% to 75%: Muck; >75%: Peat 19 Appendix D - Record of Test Borings GF� GFA INTERNATIONAL 521 N.W. ENTERPRISE DRIVE, PORT ST. LUCIE, FLORIDA 34986 PHONE: (772) 924-3575 - FAx: (772) 924-3580 STANDARD PENETRATION TEST BORING (ASTM D-1586) Client: JWN Construction Project No.: 15-1239.00 Lab No.: Project: Proposed Two -Story Residence Page: 1 of 1 Lot 1299 Nettles Island, St. Lucie County, Florida Date: 6/11/2015 Elevation: Existing Grade Drill Rig: Simco-24 Water Level: 5% feet after 0 hours Drilling Fluid commenced at depth of 10 feet Field Party: WN/JB/CS TEST LOCATION: SPT -1 N27.28463° W80.21933° Laboratory Tests Depth Blows/ N Sample Layer: USCS Description Passing Moisture Organic (feet) 6 in. Value No. From/to No. 200 Content Content 2 0-5 SP Brown fine sand, little shell, 3 trace rock fragments 1 -- -- ---- 5 8 1 •3 ---- 4 3 -- -- ------- 6 ------ 10 2 7 4 -- ---- - -- g 5 ---- 6 15 3 5-8 SP Gray fine sand, some shell 6 4 - 4 -- --- ---- 7 12 4 11 8 ---• 6 -•---- 8-9 SP Gray fine sand 9 -- -- ------ 3 ------ 5 5 9-12 CL,ML Gray fine sand and silt and clay, little shell 5 10 - 11 -------------- 12 .............. Very low drill resistance from 10 to 12 feet 13 - ----- 6--- 13%2 - 15 SP Gray fine sand, trace silt 14 -- ------ 6 8-•- 6 15 -- -14-- 16 ---- --- 17 ---- --- 18 .............. 6 18%2 - 20 SP Gray fine sand, some shell 19 -- --... 6 7 13 7 GFA INTERNATIONAL 521 N.W. ENTERPRISE DRIVE, PORT ST. LvCIE, FLORIDA 34986 PHONE: (772) 924-3575 - FAx: (772) 924-3580 STANDARD PENETRATION TEST BORING (ASTM D-1586) Client: JWN Construction Project No.:15-1239.00 Lab No.: Project: Proposed Two -Story Residence Page: 2 of 2 Lot 1299 Nettles Island, St. Lucie County, Florida Date: 6/11/2015 Elevation: Existing Grade Drill Rig: Simco-24 Water Level: 5%2 feet after 0 hours Drilling Fluid commenced at depth of 10 feet Field Party: WN/JB/CS TEST LOCATION: SPT = 1 N27.284630 W80.219330 Laboratory Tests Depth Blows/ N Sample Layer: USCS Description Passing Moisture Organic (feet) 6 in. Value No. From/to No. 200 Content Content 20 ------- ------ Very low drill resistance from 20 to 23%2 feet 21 .............. 22 ------- ------ ---- WOH=Weight of Hammer 23 ----- 24 WOH 23V - 25 CL,ML Gray silt and clay ---- 1 1- 8 25 - .2_ Very low drill resistance from 25 to 28 feet —26 -____ 27 ---- --- 28 ---- --- 9 28'/2 - 30 SP Gray fine sand, trace silt 29 .......... -9- 10 19 9 30 Moderate drill resistance from 30 to 33'/2 feet 32 ---- --- 33 .............. 33'/2 - 35 SP Gray fine sand, trace cemented sand 34 --14 __ _ 14 10 35 -_15__ _29__ 37 ------- ------ 38 .............. 38'/2 - 40 SP Gray fine sand, little cemented sand 39 -9 11 _____ 13 24 11 Boring terminated at 40 feet i Since 1988 .,. AUGER BORING LOGS WITH HAND CONE PENETROMETER (HCP) TESTS Client: JWN Construction Project: Proposed Two -Story Residence Lot 1299 Nettles Island, St. Lucie County, Florida Elevation: Existing Grade Project No: Lab No: Test Date: Technician: 15-1239.00 6/11/2015 WN/JB/CS TEST LOCATION: AB —1 N27.284640 W80.219550 HCP Depth (feet) Description (color, texture, consistency, remarks) Depth Reading 0-2 Brown fine sand, trace silt, trace shell SP 1 80+ 2 — 4% Light brown fine sand, trace shell SP 2 80+ 4'/2 — 7 Gray fine sand, trace silt, little shell SP 3 80+ 7 — 10 Gray fine sand, little silt SP-SM 4 80+ 5 80+ 6 80+ 7 80+ 8 70 9 70 10 60 Water table at 4'/ feet below ground surface Appendix E - Discussion of Soil Groups GF DISCUSSION OF SOIL GROUPS COARSE GRAINED SOILS GW and SW GROUPS. These groups comprise well -graded gravelly and sandy soils having little or no plastic fines (less than percent passing the No. 200 sieve). The presence of the fines must not noticeably change the strength characteristics of the coarse -grained friction and must not interface with it's free -draining characteristics. GP and SP GROUPS. Poorly graded gravels and sands containing little of no plastic fines (less than 5 percent passing the No. 200 sieve) are classed in GP and SP groups. The materials may be called uniform gravels, uniform sands or non -uniform mixtures of very coarse materials and very fine sand, with intermediate sizes lacking (sometimes called skip -graded, gap graded or step - graded). This last group often results from borrow pit excavation in which gravel and sand layers are mixed. GM and SM GROUPS. In general, the GM and SM groups comprise gravels or sands with fines (more than 12 percent the No. 200 sieve) having low or no plasticity. The plasticity index and liquid limit of soils in the group should plot below the "A" line on the plasticity chart. The gradation of the material is not considered significant and both well and poorly graded materials are included. GC and SC GROUPS. In general, the GC and SC groups comprise gravelly or sandy soils with fines (more than 12 percent passing the No, 200 sieve) which have a fairly high plasticity. The liquid limit and plasticity index should plat above the "A" line on the plasticity chart. , FINE GRAINED SOILS ML and MH GROUPS. In these groups, the symbol M has been used to designate predominantly silty material. The symbols L and H represent low and high liquid limits, respectively, and an arbitrary dividing line between the two set at a liquid limit of 50. The soils in the ML and MH groups are sandy silts, clayey silts or inorganic silts with relatively low plasticity. Also included are loose type soils and rock flours. CL and CH GROUPS. In these groups the symbol C stands for clay, with L and H denoting low or high liquid limits, with the dividing line again set at a liquid of 50. The soils are primarily organic clays. Low plasticity clays are classified as CL and are usually lean clays, sandy clays or silty clays. The medium and high plasticity clays are classified as CH. These include the fat clays, gumbo clays and some volcanic clays. GF� OL and OH GROUPS. The soil in the OL and OH groups are characterized by the presence of organic odor or color, hence the symbol O. Organic silts and clays are classified in these groups. The materials have a plasticity range that corresponds with the ML and MH groups. I:INN IMO73rT111 11 C-10I I &I The highly organic soils are usually very soft and compressible and have undesirable construction characteristics. Particles of leaves, grasses, branches, or other fibrous vegetable matter are common components of these soils. They are not subdivided and are classified into one group with the symbol PT. Peat humus and swamp soils with a highly organic texture are typical soils of the group. GF