1、*USACE / NAVFAC / AFCESA / NASA UFGS-02 35 27 (May 2010)-Preparing Activity: USACE SupersedingUFGS-02 35 27 (April 2006)GUIDE SPECIFICATION FOR CONSTRUCTIONReferences are in agreement with UMRL dated April 2010*SECTION TABLE OF CONTENTSDIVISION 02 - EXISTING CONDITIONSSECTION 02 35 27SOIL-BENTONITE
2、(S-B) SLURRY TRENCH05/10PART 1 GENERAL1.1 MEASUREMENT AND PAYMENT1.1.1 Measurement1.1.2 Payment1.2 DEFINITIONS1.2.1 Slurry Trench1.2.2 Slurry Method of Excavation1.2.3 Bentonite1.2.4 Slurry1.2.5 Soil Bentonite (S-B) Backfill1.2.6 Ground Water Level1.2.7 Working Surface1.2.8 Confining Stratum1.3 REFE
3、RENCES1.4 SUBMITTALS1.5 SUBMITTAL REQUIREMENTS1.6 QUALITY ASSURANCE1.6.1 Qualifications1.6.1.1 Contractor1.6.1.2 Slurry Trench Specialist1.6.1.3 Slurry Trench Excavation Equipment Operator1.7 DELIVERY, STORAGE, AND HANDLING1.8 GEOTECHNICAL SITE CONDITIONS1.8.1 Exploratory Borings1.8.2 Subsurface Con
4、ditions1.8.3 Ground Water1.8.4 Embankment ConditionsPART 2 PRODUCTS2.1 MATERIALS2.1.1 Bentonite2.1.2 Water2.1.3 Backfill Material2.2 EQUIPMENTSECTION 02 35 27 Page 1Provided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-2.2.1 Trench Excavation Equipment2.2.
5、2 Slurry Mixing and Cleaning Equipment2.2.3 Field Laboratory Equipment2.3 BENTONITE SLURRY MIXES2.3.1 Initial Bentonite Slurry Mixture2.3.2 Trench Bentonite Slurry Mixture2.3.3 Additional Bentonite2.3.4 Additives2.3.5 S-B BackfillPART 3 EXECUTION3.1 GENERAL REQUIREMENTS3.2 WORKING SURFACE3.3 SLURRY
6、TRENCH EXCAVATION3.3.1 Confining Stratum Excavation3.3.2 Blasting Plan3.4 SLURRY PLACEMENT AND TESTING3.4.1 Slurry Placement3.4.2 Slurry Testing3.5 EXCAVATED MATERIAL3.6 STABILITY3.7 TRENCH CLEANING3.8 S-B BACKFILL MIXING AND PLACEMENT3.8.1 Mixing3.8.2 Placement3.8.3 Mixing and Placing During Cold W
7、eather3.8.4 Testing3.9 SOUNDINGS3.9.1 Elevation of Top of Confining Stratum3.9.2 Elevation of Trench Bottom Prior to Backfilling3.9.3 Profile of S-B Backfill Slope and Trench Bottom3.10 AS-BUILT PROFILE3.11 TREATMENT OF TOP OF SLURRY TRENCH3.12 QUALITY CONTROL TESTING3.12.1 Bentonite Tests3.12.2 Wat
8、er Tests3.12.3 Backfill Material Tests3.12.4 Slurry Properties3.12.5 S-B Backfill Tests3.12.6 Samples of Confining Stratum3.13 CLEAN-UP- End of Section Table of Contents -SECTION 02 35 27 Page 2Provided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-*USACE /
9、 NAVFAC / AFCESA / NASA UFGS-02 35 27 (May 2010)-Preparing Activity: USACE SupersedingUFGS-02 35 27 (April 2006)GUIDE SPECIFICATION FOR CONSTRUCTIONReferences are in agreement with UMRL dated April 2010*SECTION 02 35 27SOIL-BENTONITE (S-B) SLURRY TRENCH05/10*NOTE: This guide specification covers the
10、 requirements for constructing a soil-bentonite slurry trench at both conventional and hazardous waste projects.Edit this guide specification for project specific requirements by adding, deleting, or revising text. For bracketed items, choose applicable items(s) or insert appropriate information.Rem
11、ove information and requirements not required in respective project, whether or not brackets are present.Comments and suggestions on this guide specification are welcome and should be directed to the technical proponent of the specification. A listing of technical proponents, including their organiz
12、ation designation and telephone number, is on the Internet.Recommended changes to a UFGS should be submitted as a Criteria Change Request (CCR).*PART 1 GENERAL*NOTE: In using this guide specification, the designer should realize that the requirements for the bentonite, backfill, and construction pro
13、cedure are highly dependent on the intended purpose of the slurry trench and the environment in which it is to be used.The primary considerations for S-B slurry trenches are blowout requirements, permeability, strength, and compressibility.The S-B backfill should be designed to prevent possible blow
14、out or piping of the S-B backfill into SECTION 02 35 27 Page 3Provided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-the surrounding foundation material due to the hydraulic gradient acting across the slurry trench. Design criteria are presented in Chapter
15、9, Corps of Engineers (COE) EM 1110-2-1901.The permeability for S-B slurry trenches is usually in the order of 10-6 to 10-8 cm/sec. The actual permeability of the slurry trench is dependent on both the filter cake, which forms on the sides of the trench and the S-B backfill. The contributions of bot
16、h are dependent on the relative permeability and thickness of the two materials. For design purposes, however, it is recommended that the permeability of the slurry trench be based only on the S-B backfill. For permanent or critical temporary projects, laboratory permeability tests should be utilize
17、d in establishing the mix design.When design requirements dictate, both shear strength and compressibility of the S-B backfill should be analyzed by conducting laboratory testing.Since chemical contaminants commonly associated with hazardous waste sites may increase the permeability of S-B backfill,
18、 a compatibility testing program must be undertaken prior to constructing a slurry trench. If the trench is to be excavated through contaminated material, consider performing compatibility testing using two potential backfill materials; soils to be excavated from the trench and an uncontaminated bor
19、row source. It should be noted that compatibility testing can take from 2 to 6 months to complete. For this reason, it is generally recommended that compatibility testing be completed during the design phase of the project.A recommended compatibility testing program consists of:1. Free swell (ASTM D
20、 5890) and filter cake permeability tests of several bentonites using contaminated site ground water and site mixing water that will be used during construction to determine acceptable bentonites for use on the project.2. Mix design optimization tests to determine the most economical mix of soils, d
21、ry bentonite, and bentonite slurry to produce the required permeability. This consists of short-duration (48-72 hours) permeability tests varying the amount of dry bentonite added (0, 2, and 4 percent) and if necessary the amount of additional fines added (0, 10, 20 percent) using site mixing water
22、as the permeant.3. Long-term flexible wall permeameter testing of at least 3 S-B backfill samples: the optimum mix design with site mixing water only as the permeant (control); the optimum mix design with contaminated SECTION 02 35 27 Page 4Provided by IHSNot for ResaleNo reproduction or networking
23、permitted without license from IHS-,-,-site ground water as the permeant (after 1 pore volume of site mixing water permeant to ensure a good test setup); and a bentonite content 2 percent greater than the optimum determined in step 2 with contaminated site ground water as the permeant (after 1 pore
24、volume of site mixing water permeant). It is recommended that 3 pore volumes of ground water permeant pass through the S-B backfill samples. This typically takes at least 2 months.To approximate field conditions in the lab, it is important to obtain contaminated ground water and mixing water from th
25、e site. The site mixing water used during compatibility testing shall be the water used to make the bentonite slurry during construction.For laboratory testing, consider requiring a permeability of one-half an order of magnitude less than the required field permeability (for example, 5x10-8 cm/sec i
26、n the lab for 1x10-7 cm/sec in the field).*1.1 MEASUREMENT AND PAYMENT*NOTE: Delete this paragraph when work is covered by lump-sum contract price.*1.1.1 MeasurementMeasurement for S-B Slurry Trench shall be based on the area in square meters feet of completed slurry trench measured in a vertical pl
27、ane through the centerline of the slurry trench, from the top of the working surface to the bottom of the excavated trench, and vertical lines at each corner of the full depth of the excavated trench. Measurement shall be based on surveys and soundings taken at the site as directed and approved.1.1.
28、2 PaymentPayment for S-B Slurry Trench will be made at the contract unit price per square meter foot. Such price will include costs incurred for the construction and completion of the slurry trench. No separate payment will be made for material, equipment, handling and cleaning the slurry, quality c
29、ontrol testing, record keeping, and site preparation including construction of the working surface.1.2 DEFINITIONS*NOTE: Remove items not required in the project.*The terms used in this Section are defined as follows:SECTION 02 35 27 Page 5Provided by IHSNot for ResaleNo reproduction or networking p
30、ermitted without license from IHS-,-,-1.2.1 Slurry TrenchThe slurry trench is a _ 900 mm 3 foot minimum width trench excavated through the existing ground or prepared working surface using the slurry method of excavation and backfilled with S-B backfill material, to form a low permeability cutoff wa
31、ll.1.2.2 Slurry Method of ExcavationThe slurry method of excavation consists of excavating a vertical walled trench and at the same time keeping the trench filled with a bentonite slurry mixture. The purpose of the slurry is to support the walls of the trench and prevent movement of ground water.1.2
32、.3 BentoniteBentonite is an ultrafine natural clay whose principal mineral constituent is sodium cation montmorillonite.1.2.4 SlurrySlurry is a colloidal mixture of bentonite and water.1.2.5 Soil Bentonite (S-B) BackfillS-B backfill is a homogeneous mixture of material produced by mixing soil with b
33、entonite slurry and additional dry bentonite, which is placed into the excavated trench to complete the soil-bentonite slurry trench.1.2.6 Ground Water LevelThe ground water level is the piezometric level of the ground water as determined from piezometers and wells.1.2.7 Working SurfaceThe working s
34、urface is the top of the stripped and/or prepared natural ground or the surface of previously compacted fill from which the slurry trench shall be constructed.1.2.8 Confining StratumThe confining stratum is the soil stratum or rock unit to or into which the bottom of the slurry trench is excavated.1
35、.3 REFERENCES*NOTE: This paragraph is used to list the publications cited in the text of the guide specification. The publications are referred to in the text by basic designation only and listed in this paragraph by organization, designation, date, and title.Use the Reference Wizards Check Referenc
36、e feature when you add a RID outside of the Sections Reference Article to automatically place the reference in the Reference Article. Also use the SECTION 02 35 27 Page 6Provided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-Reference Wizards Check Referenc
37、e feature to update the issue dates.References not used in the text will automatically be deleted from this section of the project specification when you choose to reconcile references in the publish print process.*The publications listed below form a part of this specification to the extent referen
38、ced. The publications are referred to within the text by the basic designation only.AMERICAN PETROLEUM INSTITUTE (API)API RP 13B-1 (2009) Recommended Practice for Field Testing Water-Based Drilling FluidsAPI Spec 13A (2006; Errata 2008) Specification for Drilling-Fluid MaterialsASTM INTERNATIONAL (A
39、STM)ASTM C 143/C 143M (2009) Standard Test Method for Slump of Hydraulic-Cement ConcreteASTM D 1140 (2000; R 2006) Amount of Material in Soils Finer than the No. 200 (75-micrometer) SieveASTM D 2216 (2005) Laboratory Determination of Water (Moisture) Content of Soil and Rock by MassASTM D 2434 (1968
40、; R 2006) Permeability of Granular Soils (Constant Head)ASTM D 422 (1963; R 2007) Particle-Size Analysis of SoilsASTM D 4318 (2005) Liquid Limit, Plastic Limit, and Plasticity Index of SoilsASTM D 5084 (2003) Measurement of Hydraulic Conductivity of Saturated Porous Materials Using a Flexible Wall P
41、ermeameterASTM D 698 (2007e1) Laboratory Compaction Characteristics of Soil Using Standard Effort (12,400 ft-lbf/cu. ft. (600 kN-m/cu. m.)U.S. ENVIRONMENTAL PROTECTION AGENCY (EPA)EPA 600/4-79/020 (1983) Methods for Chemical Analysis of Water and Wastes1.4 SUBMITTALS*SECTION 02 35 27 Page 7Provided
42、by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-NOTE: Review submittal description (SD) definitions in Section 01 33 00 SUBMITTAL PROCEDURES and edit the following list to reflect only the submittals required for the project. Submittals should be kept to the
43、minimum required for adequate quality control.A “G” following a submittal item indicates that the submittal requires Government approval. Some submittals are already marked with a “G”. Only delete an existing “G” if the submittal item is not complex and can be reviewed through the Contractors Qualit
44、y Control system. Only add a “G” if the submittal is sufficiently important or complex in context of the project.For submittals requiring Government approval on Army projects, a code of up to three characters within the submittal tags may be used following the “G“ designation to indicate the approvi
45、ng authority. Codes for Army projects using the Resident Management System (RMS) are: “AE“ for Architect-Engineer; “DO“ for District Office (Engineering Division or other organization in the District Office); “AO“ for Area Office; “RO“ for Resident Office; and “PO“ for Project Office. Codes following the
