预应力混凝土箱梁桥的温度场和应力场

为较严密地计算预应力混凝土箱梁桥实时温度应力场，提出了计算温差应力场的新方法.基于箱梁表面热交换平衡理论，综合考虑环境条件、物理材料特征、几何性质以及桥梁走向对温度应力场的影响，采用热瞬态分析和热 结构耦合求解技术，实现任意时刻箱梁结构温度应力场的仿真.以杭州湾跨海大桥为例，进行了预应力箱梁温度和应力场的数值仿真，并与按公路桥规中的温度模式所计算的结果作了比较.结果表明，该方法能客观模拟实际边界，具有较高的计算精度，能合理解释常见温度裂缝的成因.

Temperature field and stress field of prestressed concrete box-girder bridge

A new method was presented to calculate rigorously the real-time temperature-stress fields in prestressed concrete box-girder bridges.The method was based on a balancing theory of temperature distributions and exchange in box girder exterior surfaces.Considering synthetically the influences of the environmental conditions,physical and material properties,cross-section geometry and bridge location on the temperature-stress fields,the techniques of thermal instantaneous analysis and thermal-structural coupling resolve were adopted,and the temperature-stress field of box girder structure was emulated at random time.Taking the Hangzhou bay bridge as an example,the temperature fields and the stress fields of prestressed box-girder were simulated,and the obtained data were compared with that calculated by the model in the road and bridge criteria.The results show that the proposed method can emulate the actual boundary conditions verily,has high precision,and can logically explain the formation cause of temperature cracks.