【国外标准】 Standard Test Method for Sand Content by Volume of Construction Slurries

5.1 This test method is used to determine the percentage of sand by volume in construction slurry. The significance of this test method mainly relates to construction slurries used for concrete wall and drilled piers construction. The range of measurement is too limited for use in applications where the sand content is intended to be greater than 20 %, such as in the cases of cement bentonite or soil bentonite walls.5.2 A high sand content in the construction slurry is abrasive for construction plant such as pumps, and is furthermore adverse to the formation of a filter cake in applications where bentonite fluid is used to stabilize an excavation.NOTE 1: The quality of the result produced by this standard depends on the competence of the personnel performing it and the suitability of the equipment and facilities being used. Agencies that meet the criteria of Practice D3740 are generally considered capable of competent and objective testing, sampling, inspection, etc. Users of this standard are cautioned that compliance with Practice D3740 does not in itself ensure reliable results. Reliable results depend on many factors; Practice D3740 provides a means of evaluating some of those factors.1.1 This test method covers the determination of the sand content of bentonitic slurries used in slurry construction techniques. This test method has been modified from API Recommended Practice 13B.1.2 All observed and calculated values shall conform to the guidelines for significant digits and rounding established in Practice D6026.1.3 Units—The values stated in SI units are to be regarded as standard. No other units of measurement are included in this standard. Except, the sieve designation is identified using the “alternative” system in accordance with Practice E11 instead of the “standard system,” such that the sieve used is referred to as a No. 200 sieve, instead of a 75 µm sieve.1.4 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety, health, and environmental practices and determine the applicability of regulatory limitations prior to use.1.5 This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.