Influence Of Aggregate Types On Mechanical And Deformation Properties Of Concrete

The quality of aggregate is a key parameter that is a problem of technical economy. As so far, marble aggregate is not use to bigness engineering in the world. This paper study the effect of four aggregates on mechanical properties and deformation of concrete and is good to other hyperbolic dams.The paper focues on the influence of four different aggregate types which are sand stone, marble,basalt and syenite aggregates on concrete performance. The main contributions of this dissertation are summarized as follows:1) The workability of four concrete with different aggregate types is studied in this paper, and the results show that the slump of marble concrete is highest, in the other words, the marble concrete need least water.2) The compressive strength, axial tensile strength ,ultimate stretching deformatio- n, elastic modulus etc of four aggregate types concrete and mortar are discussed. The strength of basalt concrete and mortar is highest but the ultimate stretching deformation is lowest and the elastic modulus is the highest; syenite concrete and mortar is reverse. The 7d, 28d, 90d, 180d compressive strength of basalt concrete is more99%,116%,50%,55% than syenite concrete's compressive strength respectively. The earlier ages of strength of marble concrete is higher than sandstone concrete, but later age of strength of both concretes are the basic same.3) extension-compression ratio and elasitic modulus-compress strength ratio are used to analyse the crack resistence of four type aggregates concrete from the point of mechanical properties and deduce the resist crake capability is poor compare to the other three aggregate concrete, the syenite aggregate concrete's crack resistence is the best in the four aggregates concrete.4) Predict the cracking age of concrete more precisely based on the shrinkage cracking of concrete ring. Simultaneously the Ansys was also introduced to predict the cracking age of concrete ring. The predicted age of cracking was in agreement with the experimental results resonablely.The research of this dissertation is part of the projects supported by the National Natural Science Foundation of China (No.50539040)...