Test method for anti-carbonation properties and content of admixtures of common Portland cement

Abstract

The invention discloses a test method for the anti-carbonation properties and the content of admixtures of common Portland cement, which is a novel test method for determining the anti-carbonation properties of cement and the content range of the admixtures thereof through the carbonation rate of cement mortar specimens having different admixtures. Compared with the chemical analysis method, the test method has simple principles and high operability, and can comprehensively reflect the relationship between the variety and content of admixtures and the anti-carbonation properties thereof. The test method comprises the following steps: determining that the ratio of gelled materials (comprising clinker, the admixtures, and plaster) to the sand is 1:3, wherein standard sand is adopted in the testing process; determining the water requirement when the fluidity of the mortar is 185+ / -5mm; moulding mortar specimens; removing a mould after 24h of standard curing with the mould; boiling in a boiling box for 3.5h; drying for 48h at the temperature of 60 DEG C after naturally cooling; sealing the specimens with wax for one-dimensional carbonation; and conducting the test method related to concrete carbonation in GBJ 82-85 'the test method for the long-term performance and the durability of common concrete'.

Description

technical field [0001] The present invention is a new test method, by measuring the carbonization performance of cement mortar specimens with different admixture amounts, using the correlation between the carbonization rate and the admixture species and admixture amounts, to determine whether the admixture amount in cement is It exceeds the standard and belongs to the technical field of cement and concrete. Background technique [0002] In order to save costs and increase profits, cement production enterprises add more than the amount of mixed materials specified in the standard to the cement. Although the performance meets the requirements of the relevant standards when tested according to the current standard method, it may have adverse effects on the durability of cement concrete. In particular, the anti-carbonation performance may decrease, so it is of great significance to control the amount of admixture in cement. [0003] The current test method used to judge the ran...

AI Technical Summary

Problems solved by technology

However, when the concrete mix ratio is the same, the construction conditions are basically the same, and the climatic conditions are basically the same, there are often large differences in the carbonation depth of concrete of the same strength grade at various construction sites, resulting in large differences in rebound strength.