ASTM C1293-08b(2015)
測定堿硅反應導致產生的混凝土長度變化的標準試驗方法

Standard Test Method for Determination of Length Change of Concrete Due to Alkali-Silica Reaction

被代替

標準號

ASTM C1293-08b(2015)

發布

2008年

發布單位

美國材料與試驗協會

替代標準

ASTM C1293-18

當前最新

ASTM C1293-20a

 

 

引用標準

ASTM C1240 ASTM C125 ASTM C1260 ASTM C138/C138M ASTM C143/C143M ASTM C150 ASTM C157/C157M ASTM C192/C192M ASTM C227 ASTM C289 ASTM C29/C29M ASTM C294 ASTM C295 ASTM C33 ASTM C490 ASTM C494/C494M ASTM C511 ASTM C618 ASTM C702 ASTM C856 ASTM C989 ASTM D75

適用范圍

4.1 Alkali-silica reaction is a chemical interaction between some siliceous constituents of concrete aggregates and hydroxyl ions (1).5 The concentration of hydroxyl ion within the concrete is predominantly controlled by the concentration of sodium and potassium (2).

4.2 This test method is intended to evaluate the potential of an aggregate or combination of an aggregate with pozzolan or slag to expand deleteriously due to any form of alkali-silica reactivity (3,4).

4.3 When testing an aggregate with pozzolan or slag, the results are used to establish minimum amounts of the specific pozzolan or slag needed to prevent deleterious expansion. Pozzolan or slag from a specific source can be tested individually or in combination with pozzolan or slag from other sources.

4.4 When selecting a sample or deciding on the number of samples for test, it is important to recognize the variability in lithology of material from a given source, whether a deposit of sand, gravel, or a rock formation of any origin. For specific advice, see Guide C295.

4.5 This test method is intended for evaluating the behavior of aggregates in portland cement concrete with an alkali (alkali metal oxide) content of 5.25 kg/m³8201;or in concrete containing pozzolan or slag with an alkali content proportionally reduced from 5.25 kg/m³8201;Na₂O equivalent by the amount of pozzolan or slag replacing portland cement. This test method assesses the potential for deleterious expansion of concrete caused by alkali-silica reaction, of either coarse or fine aggregates, from tests performed under prescribed laboratory curing conditions that will probably differ from field conditions. Thus, actual field performance will not be duplicated due to differences in concrete alkali content, wetting and drying, temperature, other factors, or combinations of these (5).

4.6 Results of tests conducted on an aggregate as described herein should form a part of the basis for a decision as to whether precautions should be taken against excessive expansion due to alkali-silica reaction. Results of tests conducted on combinations of an aggregate with pozzolans or slag should form a part of the basis for a decision as to whether the specific pozzolan or slag, when used in the amount tested, was effective in preventing excessive expansion. These decisions should be made before a particular aggregate is used in concrete construction. Criteria to determine the potential deleteriousness of expansions measured in this test are given in Appendix X1.

4.7 When the expansions in this test method are greater than the limit shown......

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