Experimental Study on Mechanical Properties of Ultra-High-Strength Concrete with Low-Autogenous-Shrinkage

摘要

A new type of low-autogenous-shrinkage ultra-high-strength concrete with a compressive strength of more than 150 MPa has been developed for use in prestressed concrete structures. By using artificial aggregate with coal ash that has an internal-curing effect, in addition to a conventional expansive agent and shrinkage reducing agent, the effects on autogenous shrinkage reduction and compressive strength were investigated experimentally. The experimental results showed that although the artificial aggregate with coal ash causes a loss of compressive strength, it greatly contributes to the reduction of autogenous shrinkage; autogenous shrinkage of ultra-high-strength concrete can be effectively reduced by adjusting the quantity of aggregate used and the combination of admixtures used. The mechanical properties of ultra-high-strength concrete with low-autogenous-shrinkage were also evaluated, and it was confirmed that currently used estimation formulas are applicable.