1、Designation: D 6236 98 (Reapproved 2004)Standard Guide forCoring and Logging Cement - or Lime-Stabilized Soil1This standard is issued under the fixed designation D 6236; the number immediately following the designation indicates the year oforiginal adoption or, in the case of revision, the year of l
2、ast revision. A number in parentheses indicates the year of last reapproval. Asuperscript epsilon (e) indicates an editorial change since the last revision or reapproval.1. Scope1.1 This guide covers guidance for obtaining cores ofcement or lime-stabilized soil for use in determining compres-sive st
3、rength, lift thickness and bond strength, and otherphysical properties. This guide is primarily for use in coringthrough shallow (0.3 to3m(1to10ft)thick) layers of cementor lime-stabilized soils containing particles 50 mm (2 in.) indiameter to the underlying foundation.NOTE 1This guide could be used
4、 for some Class C in self-cementingfly ash materials, which may also stabilize soil.1.2 This guide does not cover material of less than 2070 kPa(300 psi) compressive strength such as cement-soil-bentonitemixtures or some controlled low strength materials (CLSM).1.3 The values stated in SI units are
5、to be regarded as thestandard. Other values are examples or for information only.1.4 This standard does not purport to address all of thesafety concerns, if any, associated with its use. It is theresponsibility of the user of this standard to establish appro-priate safety and health practices and de
6、termine the applica-bility of regulatory limitations prior to use. Specific precau-tionary statements are given in Section 8.1.5 This guide offers an organized collection of informationor a series of options and does not recommend a specificcourse of action. This guide cannot replace education orexp
7、erience and should be used in conjunction with professionaljudgment. Not all aspects of this guide may be applicable in allcircumstances. This guide is not intended to represent orreplace the standard of care by which the adequacy of a givenprofessional service must be judged, nor should this guide
8、beapplied without consideration of a projects many uniqueaspects. The word “Standard” in the title of this documentmeans only that the document has been approved through theASTM consensus process.2. Referenced Documents2.1 ASTM Standards:2C 51 Terminology Relating to Lime and Limestone (as usedby th
9、e Industry)C 219 Terminology Relating to Hydraulic CementD 559 Test Methods for Wetting and Drying CompactedSoil-Cement MixturesD 560 Test Methods for Freezing and Thawing CompactedSoil-Cement MixturesD 653 Terminology Relating to Soil, Rock, and ContainedFluidsD 1633 Test Method for Compressive Str
10、ength of MoldedSoil-Cement CylindersD 2113 Practice for Rock Core Drilling and Sampling ofRock for Site InvestigationD 4220 Practices for Preserving and Transporting SoilSamplesD 4452 Test Methods for X-Ray Radiography of SoilSamplesD 5079 Practices for Preserving and Transporting RockCore SamplesD
11、5102 Test Method for Unconfined Compressive Strengthof Compacted Soil-Lime MixturesD 5434 Guide for Field Logging of Subsurface Explora-tions of Soil and Rock3. Terminology3.1 Definitions:3.1.1 Refer to Terminology C 51 for terms relating to lime.3.1.2 Refer to Terminology C 219 for terms relating t
12、ohydraulic cement.3.1.3 Refer to Terminology D 653 for terms relating to soil.4. Summary of Guide4.1 Core samples of cement or lime-stabilized soil with acore diameter of 76- or 102-mm (3- or 4-in.) are obtainedthrough the entire thickness of a stabilized soil section orfacing using a rotary drill e
13、quipped with a diamond coring bit.1This test method is under the jurisdiction of ASTM Committee D18 on Soil andRock and is the direct responsibility of Subcommittee D18.15 on Stabilization WithAdmixtures.Current edition approved May 1, 2004. Published June 2004. Originallyapproved in 1998. Last prev
14、ious edition approved in 1998 as D 6236 - 98.2For referenced ASTM standards, visit the ASTM website, www.astm.org, orcontact ASTM Customer Service at serviceastm.org. For Annual Book of ASTMStandards volume information, refer to the standards Document Summary page onthe ASTM website.1Copyright ASTM
15、International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959, United States.To minimize the possibility of breakage or other internaldamage to the sample during coring operations, it is suggestedthat the stabilized soil have a minimum compressive strengthof 2070 kPa (300 psi)
16、prior to coring, cores are retrieved,labeled, and logged. Coring may be repeated at other times ifspecified by the engineer. Retrieved core is tested as specifiedby the engineer. Tests commonly requested include unconfinedcompressive strength in accordance with Test Methods D 1633and D 5102, durabil
17、ity in accordance with Test Methods D 559and D 560, bond strength in accordance with the pendingASTM standard for direct shear testing of rock, and uniformityand possible voids in accordance with Test Methods D 4452.5. Significance and Use5.1 Coring is performed to evaluate construction control andp
18、hysical properties of stabilized soil.5.2 Coring is conducted to determine the quality and thetotal thickness of the stabilized soil and to evaluate bondingbetween lifts.5.3 Coring stabilized soil before it has curved to at least2070 kPa (300 psi) compressive strength can cause excessivebreakage in
19、the core.5.4 If lab-cured specimens are prepared, samples may becored to correlate with specified break intervals of the lab-cured specimens. Typical time intervals are 7, 28, 60, and/or 90days after placement. Twenty-eight (28) days after placement isthe most common time interval for first drilling
20、 cores.6. Interferences6.1 Failure to adequately stabilize the drill and drill standduring coring can cause excessive breakage in the core.6.2 Failure to set up the drill and drill stand perpendicular tothe surface of the stabilized soil will cause error in determiningthe thickness of the stabilized
21、 material.7. Apparatus7.1 Drill and Drill StandA rotary drill capable of drilling102-mm (4-in.) diameter core samples to the required depth(generally 0.3 to 1.2 m (1 to 4 ft). The drill must be capable ofdrilling holes perpendicular to the face of the stabilized soil.The drill should be mounted and
22、the drill stand anchored sothat the drill and stand are stable during the drilling process.7.2 Core BarrelsDiamond surface set or diamond impreg-nated core bits, 76- or 102-mm (3- or 4-in.) inside diameter, ofsufficient length to penetrate the full vertical depth of thestabilized material.7.3 Adapte
23、rsRemovable extension adapters and exten-sions rods compatible with drill and core barrels.7.4 WaterWater supply for drilling to remove cuttings andcool drill bits.7.5 GeneratorPortable electric generator suitable for sup-plying electric power to drill.7.6 Percussion DrillRotary percussion drill or
24、other suit-able device holes for anchor bolts.7.7 AnchorsAnchors and bolts adequate for securing thedrill stand to the stabilized material.7.8 Core Retrieval BarrelsWorn 76- or 102-mm (3- or4-in.) diameter core bits with cutting edge removed and slottedon the drilling end for retrieving core samples
25、 (Fig. 1).7.9 Pry BarMetal bar suitable for breaking core from thebottom of the hole.7.10 ContainersContainers shall be in accordance withPractices D 5079 or D 4220.7.11 Grouting MaterialsPotable water, concrete premix,bagged cement, or grout premix for back filling drill holes.7.12 Miscellaneous Eq
26、uipmentAssorted tools necessaryfor drilling operations, chain tongs and pipe wrenches forinstalling and removing core barrels, and water proof markersfor labeling core samples.8. Hazards8.1 Safety Hazards:8.1.1 Safety hazards may be involved in the use of the rotarydrill. Refer to the manufacturers
27、handbook before operatingthe drill.8.1.2 Ensure that electrical supply lines are well insulatedand connections kept dry to prevent electrical shock.8.1.3 Use caution when refilling gasoline tanks on electricalgenerators.8.1.4 Drilling equipment and core samples are heavy andawkward. Use care when li
28、fting or transporting equipment orsamples.8.1.5 Drilling operations often take place on sloped sur-faces. Adequate safety shoes or safety boots should be worn toprevent slipping into machinery or down the slope.8.1.6 Wear safety glasses and hard hat.8.1.7 Use of a respirator may be necessary.8.2 Tec
29、hnical Hazards:8.2.1 Because of low early compressive strength, it may bedifficult to obtain representative intact core samples until thestabilized soil has reached a compressive strength of 2070 kPa(300 psi).9. Sampling, Test Specimens, and Test Units9.1 Core drill hole locations and depths are bas
30、ed on thedesign of the stabilized soil-lime or soil-cement structure.General hole locations and core diameters required for testingshould be determined prior to the start of construction. Coresshould also be obtained in any area of questionable stabilizedsoil quality.10. Conditioning10.1 Identify, p
31、lace core samples in shipping boxes, andcover immediately after retrieval to minimize moisture loss inaccordance with Practices D 4220 and D 5079.11. Procedure11.1 Record all data on an appropriate log form. Examplesof soil-cement and soil-lime logs are shown in Figs. 2 and 3.11.2 CoringCoring is do
32、ne when the strength of thestabilized soil has reached approximately 2070 kPa (300 psi).Time to reach this strength will vary depending on mix design.Time interval after placement until sample is cored should becoordinated with specified break intervals of lab-cured speci-mens if such were prepared
33、or specified by an engineer.Common time intervals are 7, 28, 60, and/or 90 days. If coringis repeated, subsequent holes should be immediately adjacentto the previous holes.D 6236 98 (2004)211.2.1 Anchor the drill stand in a manner which effectivelystabilizes the drill and drill stand during drilling
34、 and allows forcoring and core retrieval to be perpendicular to the placementlifts.NOTE 2Core barrels should remain perpendicular to the face of thestabilized soil, and the drill and stand should be stable while drilling toprevent core from binding in the barrel.11.2.2 As required, install a 76- or
35、102-mm (3- or 4-in.)inside diameter core barrel of sufficient length to penetrate thefull vertical depth of the stabilized material facing.11.2.3 In one continuous operation, drill through the entiredepth of the stabilized soil to the embankment or foundationcontact.NOTE 3Drilling should be performe
36、d at a slow rational speed, withconstant feed pressure, such that the core is not damaged during thedrilling operations. Because of the great variation in strength of thematerial, depending on mix design and time of sampling, no one rationalspeed or feed rate can be specified. However, note that the
37、 material maybe fragile and can easily be damaged in drilling.FIG. 1 Core Retrieval Barrel Made From Worn Diamond Studded Core BarrelD 6236 98 (2004)311.2.3.1 If the core has broken and is binding in the corebarrel, stop drilling, remove the core barrel, and retrieve anybroken pieces of core remaini
38、ng in the hole with the coreretrieval barrel before continuing.11.2.3.2 If the depth of the stabilized material exceeds themaximum length of the core barrel, remove the core barrel andretrieve the core with the core retrieval barrel. Add anextension rod and continue drilling to embankment or founda-
39、tion contact.11.2.4 Remove the core barrel, and install a core retrievalbarrel of sufficient length to remove the core in one piece.11.2.5 Retrieve the core in one operation by inserting thecore retrieval barrel over the full length of core and extractingboth from the hole. As soon as the core retri
40、eval barrel and coreare out of the hole, place a cover over the hole to prevent thecore from falling back into the hole.NOTE 4Caution: Take care when handling recovered samples tominimize disturbance, which can affect test results strength and perme-ability.11.2.6 Remove the core retrieval barrel fr
41、om the drill, andcarefully remove the core from the barrel by pushing the coreout the top. Immediately place the core in a shipping box in theexact order that it was retrieved.11.3 Logging CoreLog all core as it comes from theretrieval barrel and is placed in the shipping box.11.3.1 Immediately labe
42、l the core by hole number and itsposition in the hole from top to bottom. Indicate the directionof top on each piece of core.11.3.2 To prevent moisture loss, place the samples inairtight plastic bags prior to placing in shipping container.Keep samples out of direct sunlight.FIG. 2 Log of Soil-Lime D
43、rill Hole (SI Example)D 6236 98 (2004)411.3.3 On an appropriate form or by electric means, note thedrilling method, drill run intervals, depth at which breaks occurin the core, lift contacts, embarkment or foundation contact,bonding agent used (if any), and condition of bond. Include anyother pertin
44、ent information, such as spun core, loose material,surface appearance, poor compaction, clayballs, unhydratedlime concentrations, fractures, lack of bonding, etc. An ex-ample of appropriate forms for soil-lime and soil-center areshown in Figs. 2 and 3.11.3.4 Immediately After Logging, carefully and
45、securelypack each section of core in the shipping box in accordancewith Practice D 5079 to prevent moisture loss and damageduring transport to laboratory for testing.11.4 Refilling HolesRefill all core holes with grout, con-crete premix slurry, or stabilized soil mixed to original place-ment specifi
46、cations.12. Report12.1 Report the following information:12.1.1 A log for each hole drilled and completed as specifiedin 11.3.2,FIG. 3 Log of Soil-Cement Drill Hole (Ft/lb Example)D 6236 98 (2004)512.1.2 Location and condition (backfilled, capped, etc.) ofdrill hole, and12.1.3 Disposition of core sam
47、ples13. Precision and Bias13.1 This guide provides qualitative and general informa-tion only. Therefore, a precision and bias statement is notapplicable.14. Keywords14.1 coring; logging; soil-cement; soil-lime; soilstabilizationASTM International takes no position respecting the validity of any pate
48、nt rights asserted in connection with any item mentionedin this standard. Users of this standard are expressly advised that determination of the validity of any such patent rights, and the riskof infringement of such rights, are entirely their own responsibility.This standard is subject to revision
49、at any time by the responsible technical committee and must be reviewed every five years andif not revised, either reapproved or withdrawn. Your comments are invited either for revision of this standard or for additional standardsand should be addressed to ASTM International Headquarters. Your comments will receive careful consideration at a meeting of theresponsible technical committee, which you may attend. If you feel that your comments have not received a fair hearing you shouldmake your views known to the ASTM Committee on Standards, at the address shown
