大体积混凝土的特点及其温度裂缝产生机理

Characteristic and Temperature Crack Controlling of Large-volume Concrete

大体积混凝土温度裂缝一直是制约大型公共建筑建设和发展的一个重要原因。水泥的水化一直存在于混凝土结构浇筑的整个过程中,期间水泥释放大量的水化热提高了混凝土自身的温度,产生的热量引起温度膨胀或温度收缩变形,从而导致在结构受到约束限制时将出现很大的张拉温度应力,假如应力大于混凝土的极限抗拉强度,从而产生表面裂纹或者贯穿裂纹,威胁到建筑的安全性和耐久性。在详细分析大体积混凝土特点的基础上,对大体积混凝土温度裂缝的产生机理进行了详细的分析和研究。

Temperature crack of large-volume concrete has been an important factor restricting the construction and development of large public buildings. The hydration of cement has been exist in the whole process of concrete pouring,and release a large number of cement hydration heat which lead to temperature increment of the concrete itself. The heat generated by expansion or contraction deformation temperature,which lead to large tensile temperature stress when the structure is constrained. If the stress is greater than the ultimate tensile strength of concrete,the surface cracks or through-wall cracks can be produced,threatening the safety and durability of the building. Based on the detailed analysis of the characteristics of large volume concrete,this paper analyzed and studied the mechanism of temperature crack of large-volume concrete.