定价： 260元 / 折扣价： 221 元 加购物车

定价： 605元 / 折扣价： 515 元 加购物车

4.1 As described in Guide C1894, the MIC of concrete is considered to be a three-stage process with the reduction in pH (Stage I) (for example, 12.5 > pH > 9-10), the establishment of biofilms which further lowers the pH (Stage II) (for example, 9-10 > pH > 4-6) and eventual deterioration due to biogenic acid exposure (Stage III) (for example, < ~4 pH). This standard provides standard test methods to assess the effects of different stages of MIC on concrete products and efficacy of antimicrobial products used in or on concrete.4.2 The tests are performed in simulated exposure solutions containing well-controlled bacterial strains that are grown in the laboratory. These tests do not require an environmental chamber and are intended to be performed as benchtop tests in biosafety level 1 laboratory conditions. These tests are suitable for simulation of the Stage II and III of MIC because the pH range of the solution can be controlled within the ranges of each stage.4.3 This standard provides three test methods.4.3.1 Test Method A is suitable for assessing the efficacy of antimicrobial admixtures in delaying or preventing biogenic acidification in a nutrient-rich simulated wastewater exposure solution.4.3.2 Test Method B is suitable for assessing the effectiveness of antimicrobial admixtures in a prescribed cementitious system (Option B1) or assessing the performance of different cementitious systems (Option B2) in delaying or preventing microbially-induced corrosion of concrete in the Stage II of MIC.4.3.3 Test Method C is suitable for assessing the suitability of cementitious systems in delaying or preventing microbially-induced corrosion of concrete in the Stage III of MIC.4.4 The results obtained by these test methods should serve as information to be used with Guide C1894 in, but not as the sole basis for, selection of a biologically-resistant material for a particular application. No attempt has been made to incorporate into these test methods all the various factors that may affect the performance of a material when subjected to actual service.1.1 This standard presents test methods for the determination of the effects of biogenic acidification on concrete products and/or efficacy of antimicrobial products to resist microbially-induced corrosion (MIC) of concrete. In these tests, the biogenic acidification is achieved by sulfur-oxidizing bacteria (SOB) that can convert elemental sulfur or thiosulfate to sulfuric acid without the use of H2S gas.1.2 This standard is referenced in the guideline document for MIC of concrete products. Guide C1894 provides guidance for microbially-induced corrosion of concrete products and an overview of where this test, and its options, can and should be used. This document is not intended to be a guideline document for MIC of concrete products.1.3 This standard does not cover controlled breeding chamber tests, in which H2S gas is produced by bacterial activity and acidification is the result of the conversion of this H2S gas to sulfuric acid.1.4 This standard does not cover chemical acid immersion tests, in which acidification is achieved by chemical sulfuric acid addition, not by bacterial activity. Testing protocols for chemical acid immersion are described in Test Methods C267 and C1898.1.5 This standard does not cover tests that assess field exposure conditions or sewage pipe, concrete tank, or concrete riser network design.1.6 This standard does not cover live trial tests where concrete coupons or other specimens are monitored in sewers.1.7 The tests described in this standard should not be performed on concrete samples that have already been exposed to MIC conditions.1.8 This standard does not cover concrete deterioration due to chemical sulfate attack, which is caused by the reaction of sulfate compounds that exist in wastewater with the hydration products of cement. Test methods for assessing sulfate attack are provided by Test Methods C452 and C1012/C1012M.1.9 The values stated in SI units are to be regarded as standard. No other units of measurement are included in this standard.1.10 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.1.11 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.

定价： 646元 加购物车

定价： 571元 加购物车

定价： 345元 / 折扣价： 294 元 加购物车

定价： 1092元 / 折扣价： 929 元 加购物车

This specification covers mill-mixed gypsum concrete, consisting essentially of calcined gypsum and suitable aggregate, requiring the addition of water only at the job site. Gypsum concrete is intended for use in the construction of poured-in-place roof decks or slabs. Two classes, based on the compressive strength and density, are covered. Gypsum concrete shall consist of calcined gypsum to which are added aggregates, wood chips, or wood shavings in proportion to meet the applicable requirements of this specification. Test method in this specification shall be performed in order to determine the physical properties of the gypsum concrete. Setting time is determined by the Vicat method.1.1 This specification covers mill-mixed gypsum concrete, consisting essentially of calcined gypsum and suitable aggregate, requiring the addition of water only at the job site. Gypsum concrete is intended for use in the construction of poured-in-place roof decks or slabs. Two classes, based on the compressive strength and density, are covered.1.2 The values stated in either inch-pound units or SI units are to be regarded separately as standard. The values stated in each system may not be exact equivalents; therefore, each system shall be used independently of the other. Combining values from the two systems may result in nonconformance with the standard.1.3 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.

定价： 515元 加购物车

定价： 156元 / 折扣价： 133 元 加购物车

定价： 0元 / 折扣价： 0 元 加购物车

5.1 The shear strength between segmental concrete units (with and without geosynthetic reinforcement) is used in design of reinforced soil retaining walls.5.2 This test is used to determine the shear strength for the design of the facing stability of segmental retaining walls. Performing a series of these shear tests at varying normal loads permits development of a relationship between shear strength and normal load. This relationship may be linear, bilinear, or some other complex mathematical expression.5.3 This shear strength test is meant to be a performance test (laboratory or field); therefore, it should be conducted using full-scale system components. The conditions for the test are selected by the user and are not for routine testing.5.4 As a performance test on full-scale system components, it accounts for some of the variables in construction procedures and materials tolerance normally present for these types of retaining wall systems.1.1 This test method is used to determine the shear strength between two layers of segmental concrete block units used in construction of reinforced soil retaining walls. The test is carried out under conditions determined by the user that reproduce the facing system at full scale. The results of a series of tests are used to define a relationship between shear strength developed between segmental concrete units and normal load.1.2 This is a performance test used to determine properties for design of retaining wall systems utilizing segmental concrete units and soil reinforcing geosynthetics, either geotextiles or geogrids. The test is performed on a full-scale construction of the facing system and may be run in a laboratory or the field.1.3 The values stated in SI units are regarded as the standard. The values stated in inch-pound units are provided for information only.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.

定价： 702元 加购物车

4.1 The testing and inspection of concrete and concrete aggregates are important elements in obtaining quality construction. A testing agency providing these services shall be selected with care.4.2 A testing agency shall be deemed qualified to perform and report the results of its tests if the agency meets the requirements of this practice. The testing agency services shall be provided under the technical direction of a registered professional engineer.4.3 This practice establishes essential characteristics pertaining to the organization, personnel, facilities, and quality systems of the testing agency. This practice may be supplemented by more specific criteria and requirements for particular projects.1.1 This practice identifies and defines the duties, responsibilities, and minimum technical requirements of testing agency personnel and the minimum technical requirements for equipment utilized in testing concrete and concrete aggregates for use in construction.1.2 This practice provides criteria for the evaluation of the capability of a testing agency to perform designated ASTM test methods on concrete and concrete aggregates. It can be used by an evaluation authority in the inspection or accreditation of a testing agency or by other parties to determine if the agency is qualified to conduct the specified tests.NOTE 1: Specification E329 provides criteria for the evaluation of agencies that perform the inspection of concrete during placement.1.3 This practice provides criteria for Inspection Bodies and Accreditation Bodies that provide services for evaluation of testing agencies in accordance with this practice.1.4 The text of this standard references notes and footnotes, which provide explanatory material and shall not be considered as requirements of this standard.1.5 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.1.6 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.

定价： 590元 加购物车

定价： 515元 加购物车

定价： 702元 加购物车

定价： 646元 加购物车

This specification covers the standards for hot-applied crack filler proposed for use in filling cracks in asphalt concrete and portland cement concrete pavements. The filler shall be a compound that will effectively fill cracks in concretes and shall resist softening and pickup by vehicle tires at ambient summer temperatures. The fillers shall also comply with the requirements set for the safe heating temperature, softening point, cone penetration, resilience, and asphalt compatibility.1.1 This specification covers hot-applied crack filler for use in filling cracks in asphalt concrete and portland cement concrete pavements.1.2 The values stated in either SI units or inch-pound units are to be regarded separately as standard. The values stated in each system may not be exact equivalents; therefore, each system shall be used independently of the other. Combining values from the two systems may result in nonconformance with the standard.1.3 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.1.4 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.

定价： 515元 加购物车