Influence of Restrained Condition on Mechanical Properties, Frost Resistance, and Carbonation Resistance of Expansive Concrete

Abstract

This paper presents the results of an experimental investigation of the effect of the restrained condition on the mechanical properties, frost resistance, and carbonation resistance of expansive concrete with different water–binder ratios. In this study, length change ratio test, expansion strain test, compressive strength test, mercury intrusion porosimetry test, underwater weighing test, freezing–thawing test, and accelerated carbonation test were performed to evaluate the mechanical properties, pore size distribution, total porosity, and durability of expansive concrete under both restrained and unrestrained conditions. The test results indicate that the length change ratio and expansion strain of the expansive concrete were controlled by the restrained condition. The compressive strength of expansive concrete was enhanced by the triaxial restraining when the amount of expansive additive was 40 kg/m3 of concrete. Two hypotheses were described to explain the change of pore structure change expansive mortar. The results also indicate that the carbonation resistance and frost resistance were improved by the uniaxial restrained condition. Furthermore, the effect of the restrained condition must be considered to evaluate not only the experimental results of the expansive concrete with a high EX replacement level but also the expansive concrete combining other cement replacement materials.

Chemical prestressing of concrete structures; state of the art review

“…Still, whether the influence is positive or negative, the literature shows that it is slight and insignificant. 57,58,81,82 Regardless, using superplasticizer is a requirement, especially with high strength concrete when the water/ cement ratio is low. There are a number of superplasticizer available; however, Zdanowicz 23 has shown that polycarboxylate ether (PCE) superplasticizers are more effective in promoting expansion than other types.…”

“…There are conflicting reports regarding the influence of CSA on the workability of fresh concrete. Still, whether the influence is positive or negative, the literature shows that it is slight and insignificant 57,58,81,82 . Regardless, using superplasticizer is a requirement, especially with high strength concrete when the water/cement ratio is low.…”

Influence of the Type of Cement on the Action of the Admixture Containing Aluminum Powder

“…Expansive concretes made of expansive cements are characterized by lower total porosity and thus lower permeability of composite, as well as better frost resistance and higher strength compared to concretes from non-expansive cements [ 5 ]. The disadvantage of sulfate-containing expansive cements is the possibility of the formation of ettringite after the cement sets, which leads to cracking of the cement matrix.…”