超长混凝土结构硬化阶段温度作用有限元分析

Finite element analysis On temperature effect of super-length concrete structure hardened

超长混凝土结构硬化阶段的裂缝,由于影响因素的复杂性和结构的空间效应,很难采用手算法进行定量运算.利用ANSYS有限元程序建立瞬态温度场的分析模型,并对北京某实验用房在混凝土硬化阶段温度场和应力场进行了数值计算分析.计算结果表明混凝土经历了先压后拉的受力过程,温度应力由结构的两端向中心逐步增大,并与结构长度相关.在施工中采取必要的保温和散热措施、合理控制结构内的温度梯度,就可增加设缝间距,并避免裂缝产生.

Cracks of The super-length concrete structure in hardened stage,because of the complicated factors and the space effect of structure,it is difficult to adopt quantitative operations in hand.Using the ANSYS finite element program to create the transient temperature field analysis model,and the numerical analysis of temperature field and stress field for the practical project of Beijing experimental housing is carried out.The calculation results show that the first concrete experience was the stress process after pressure,temperature stress on both ends by structure to center,and increasing the structural length.Heat of preservative measures were taken In the construction,and the temperature gradients were reasonable controlled within the structure,that can avoid concrete cracks.