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HomeMy WebLinkAboutKEY TO BORING LOGSQ 0 5 12 W W N 0 0 N 0 z 50 .: 0 Z a 0 70 =. 85 100 ' J KEY TO BORING .LOGS SOIL CLASSIFICATION CHART* Sand or Gravel [SP,SW,GP,GW] Sand or Gravel with Silt or Clay [SP.SM,SP-SC] Silt or Claayy':eyy;SBnd or Gravel ($.M;SC,GM,GC] Sandy or Gravellyy S[It;orCla'y [ML, L-ML,gi;MH,CH,Q .Q I Sik'or Giayy;vr(th':Sarit :oriGravel [INL yCI.=MG;CI:;MH;CH;OL';QH]' Silt or'C[tiyy [MLiCL?IVIL;CL,MH,CH,OL,OH] 60 6o 0 40 >z U 30 F g 20 o. 10: 'o 9=]"SCIENCES, li1�IVERSaL ENGINEERING INC. 0. 10 20 30 40 60 60 70 8D 9D 100 LIQUID LIMIT PLASTICITY CHART GROUP NAME AND SYMBOL COARSE GRAINED SOILS ♦ � —. . •. • WELL -GRADED SANDS [SWI �'� I-' WELL -GRADED GRAVELS [GW] t r POORLY -GRADED SANDS [SP] oo o D POORLY -GRADED GRAVELS [GP] POORLY-GRAOED' SANDS WITH SILT POORLY -GRADED GRAVELS WITH SILT MI s. •' • POORLY -GRADED SANDS WITH CLAY [SP-SC] ° POORLY -GRADED GRAVELS WITH CLAY IGP-GC] SILTYSANDS ISM] o ° p •Q SILTY GRAVELS [GM] CLAYEY SANDS LSDI ' . CLAYEY GRAVELS IGCI FINE GRAINED SOILS HIGHLY ORGANIC SOILS INORGANIC SILTS, SLIGHT PLASTICITY ORGANIC SILTSICLAYS LOW PLASTICITY [OL]:. [ML] INORGANICSI LTY CLAY ORGANIC SILTS/CLAYS LOW PLASTICITY MEDIUM TO HIGH [CL.MLI PLASTICITY [OH].. INORGANIC CLAYS r PEAT, HUMUS, SWAMP SOILS LOW TO MEDIUM �+ �� i+ �t WITH NIGH ORGANIC PLASTICITY[CLI _ CONTENTS[PT]" INORGANIC SILTS HIGH PLASTICITY [MHI RELATIVE DENSITY INORGANIC CLAYS HIGH (SAND AND GRAVEL) PLASTICITY[CH] VERY LOOSE - 0 to 4 Blowslft. LOOSE - 5 to 10 Blowslft. • MEDIUM DENSE -11 to 30 Blowslft DENSE - 31 to 50 Blowsift VERY DENSE - more than 50 BiowsRt. IN ACCORDANCE WITH ASTM D 2487 - UNIFIED SOIL SILTY CLAYEY SANDS OR [SCSM] 'CLASSIFICATION SYSTEM. '• LOCALLY MAY BE KNOWN AS MUCK. NOTES: 8' - DENOTES DYNAMIC CONE PENETROMETER (DCP) VALUE R.- DENOTES REFUSAL TO PENETRATION P - DENOTES PENETRATION WITH ONLY WEIGHT OF DRIVE HAMMER NIE • DENOTES GROUNDWATER TABLE NOT ENCOUNTERED NOTE:DUAL SYM OLtARE USED TO INDICATE BORDERLINE SOIL CLASSIFICATIONS CONSISTENCY (SILT AND CLAY) VERY SOFT- 0 to 2 Blowslft. SOFT - 3 to 4 Blowsltt. FIRM - 5 to 8 Blowslft. STIFF -a to 18 Blowsfft. VERY STIFF -17 to 30Blowsllt HARD - more than 30 Blowsltt. APPENDIX A.1 G � 1-0 eering Report The Geoprofesslonal Business Assodation (GBA) has prepared this advisory to help you — assumedly a client'representative — interpret and apply this geotechnical=engineering report as effectively as possible. In that way, cllents_can benefit from a lowered exposure to the-tubsurf=6 problems that, for decades, have been a principal cause of construction delays, cost overruns, claims, and disputes. If you have questions or want more information about any of the issues discussed below, contact your GBA-inember geotechnical engineer. Active involvement In the Geoprofessional Business Association exposes geotechnical engineers to a wide'array of risk -confrontation techniques that can be of genuine benefit for everyone involved with a construction project. Geotechnical-Engineering Services Are Performed for Specific Purposes, Persons, and Projects Geotechnical engineers structure their services to meet the specific needs of their clients. A geotechnical-engineering study conducted for a given civil engineer will not likely meet the needs of a civil - works constructor or even a different civil engineer. Because each geotechnical-engineering study is unique; each geotechnical- engineering report is unique, prepared solely for the client. Those who rely on a geotechnical-engineering report prepared for a different client can be seriously misled. No one except authorized client representatives should rely on this geotechnical-engineering report without first conferring with the geotechnical engineer who prepared it. And no one — not even you — should apply this report far any purpose or project except the one originally contemplated. . . Read this Report In Full Costly problems have occurred because those relying on a geotechnical- engineering report did not read it in its entirety. Do not rely on an executive summary Do not read selected elements only. Read this report in full. You Need to Inform Your Geotechnical. Engineer about Change Your geotechnical engineer considered unique, project -specific factors when designing the study behind this report and developing the confirmation -dependent recommendations the report conveys. A few typical factors include; the clients goals, objectives, budget, schedule, and risk -management preferences, - the general nature of the structure involved, its size, configuration, and performance criteria; • the structure's location and orientation on the site; and • other planned or existing site improvements, such as retaining walls, access roads, parking lots, and uridewound utilities. Typical changes that could erode the reliability of this report include those that affect - the sites size or shape; • 'the function of the proposed structure, as when its changed from a parking garage to an office building, or from a light -industrial plant to a refrigerated warehouse; the elevation, configuration, location, orientation, or weight of the proposed structure; the composition of the design team; or project ownership. As a general rule, always inform your geotechnical engineer of project changes — even minor ones — and request an assessment of their impact. The geotechnical: engineer who prepared this report cannot accept responsibility or liability for problems that arise because the ggotechnical engineer was not informed about developments the engineer otherwise would have considered. This Report May Not Be' Reliable Do not rely on this report if your geotechnical engineer prepared it: • for a different client, • for a different project; • for a different site (that may or may not include all or a portion of the original site); or • before important events occurred at the site or adjacent to it; e.g., man-made events like construction or environmental remediation, or natural events like floods, droughts, earthquakes, or groundwater fluctuations. ' Note, too, that it could be unwise to rely on a geotechnical-engineering report whose reliability may have been affected by the passage of time, because of factors like changed subsurface conditions; new or modified codes, standards, or regulations; or new techniques or tools.: If your geotechnical engineer has not indicated an "apply -by" date on the report, ask what it should be, and, in general, ifyou are the least bit uncertain about the continued reliability of this report, contact your geotechnical engineer before applying it. A minor amount of additional testing or analysis - if any is required at all - could prevent major problems. Most of the "Findings" Related in This Report Are Professional Opinions Before construction begins, geotechnical engineers explore a site's subsurface through various sampling and testing procedures. Geotechnical engineers can observe actual subsurface conditions only at those'specific locations where sampling•and testing were performed. The data derived from that sampling and testing were reviewed by your geotechnical engineer, who then applied professional judgment to form opinions about subsurface conditions throughout the site. Actual sitewide-subsurface conditions may differ — maybe significantly — from those indicated in this report. Confront that risk by retaining your geotechnical engineer to serve on the design team from project start to project finish, so the individual can provide informed guidance quickly, wheneveI needed. This Report's Recommendations Are Confirmation -Dependent The recommendations included in this report —including any options or alternatives — are confirmation -dependent. In other words, they are not final, because the geotechnical engineer who developed them relied heavily on judgment and opinion to do so. Your geotechnical engineer can finalize the recommendations only after observing actual subsurface conditions revealed during construction. If through observation your geotechnical engineer confirms that the conditions assumed to exist actually do exist, the recommendations can be relied upon, assuming no other changes have occurred. The geotechnical engineer who prepared this report cannot assume responsibility or liability for confirmation - dependent recommendations if you fail to retain that engineer to perform construction observation. This Report Could Be Misinterpreted Other design professionals' misinterpretation of geotechnical- engineering reports has resulted in costly problems. Confront that risk by having your geotechnical engineer serve as a full-time member of the design team, to: • confer with other design -team members, • help develop specifications, • review pertinent elements of other design professionals' plans and specifications, and • be on hand quickly whenever geotechnical-engineering guidance is needed. You should also confront the risk of constructors misinterpreting this report Do so by retaining your geotechnical engineer to participate in prebid and preconstruction conferences and to perform construction observation. Give Constructors a Complete Report and Guidance Some owners and design professionals mistakenly believe they can shift unanticipated -subsurface -conditions liability to constructors by limiting the information they provide for bid preparation. To help prevent the costly, contentious problems this practice has caused, include the complete geotechnical-engineering report, along with any attachments or appendices, with your contract documents, but be certain to note conspicuously that you've included the material for informational purposes only. To avoid -misunderstanding, you may also want to note that "informational purposes" means constructors have no right to rely on the interpretations, opinions, conclusions; or recommendations in the report, but they may rely on the factual data relative to the specific times, locations, and depths/elevations referenced. Be certain that constructors know they may learn about specific project requirements, including options selected from the report, only from the design drawings and specifications. Remind constructors that they may perform their own studies if they want to, and be sure to allow enough time to permit them to do so. Only then might you be in a position to give constructors the information available to you, while requiring them to at least share some of the financial responsibilities stemming from unanticipated conditions. Conducting prebid and preconstruction conferences can also be valuable in this respect. Read Responsibility Provisions Closely Some client representatives, design professionals, and constructors do not realize that geotechnical engineering is far less exact than other engineering disciplines. That lack of understanding has nurtured unrealistic expectations that have resulted in disappointments, delays, cost overruns, claims, and disputes. To confront that risk, geotechnical engineers commonly include explanatory provisions in their reports. Sometimes labeled "limitations," many of these provisions indicate where geotechnical engineers responsibilities begin and end, to help others recognize their own responsibilities and risks. Read these provisions closely. Ask questions. Your geotechnical engineer should respond fully and frankly. Geoenvironmental Concerns Are Not Covered The personnel, equipment, and techniques used to perform an environmental study — e.g., a "phase -one' or "phase -two" environmental site assessment — differ significantly from those used to perform a geotechnical-engineering study. For that reason, a geotechnical- engineering report does not usually relate any environmental findings, conclusions, or recommendations; e.g., about the likelihood of encountering underground storage tanks or regulated contaminants. Unanticipated subsurface environmental problems have led to project failures. If you have not yet obtained your own environmental information, ask your geotechnical consultant for risk -management guidance. As a general rule, do not rely on an environmental report prepared for a different client, site, or project, or that is more than six months old. Obtain Professional Assistance to Deal with Moisture Infiltration and Mold While your geotechnical engineer may have addressed groundwater, water infiltration,. or similar issues in this report, none of the engineer's services were designed, conducted, or intended to prevent uncontrolled migration of moisture — including water vapor — from the soil through building slabs and walls and into the building interior, where it can cause mold growth and material -performance deficiencies. Accordingly, proper implementation of the geotechnical engineer's recommendations will not of itself be sufficient to prevent moisture infiltration. Confront the risk of moisture infiltration by including building -envelope or mold specialists on the design team. Geotechnical engineers are not building - envelope or mold specialists. GEOPROFESSIONAL MR BUSINESS ASSOCIATION Telephone: 301 /565-2733 e-mail: info@geoprofessional.org www.geoprofessionaLorg Copyright 2016 by Geoprofessional Business Association (GBA), Duplication, reproduction, or copying of this document, in whole or in part, by any means whatsoever, is strictly prohibited, except with GBA's specific written permission. Excerpting, quoting, or otherwise extracting wording from this document is permitted only with the express written permission of GBA, and only for purposes ofscholarly research or book review. Only members oFGBA may use this document or its wording as a complement to or as an element of a report of any kind, Any other firm, individual, or other entity that so uses this document without being a GBA member could be committint negligent