Application of Thermal Stress Controlling in Construction of Large Bridge Cushion Cap

摘要

With respect to the construction of large bridge cushion cap concrete without poured joint in deep water, thermal stress during concrete hardening is destructive to durability. In this paper, a concrete thermal stress physical formula represented by the deformation component and variable temperature component is given based on the analysis of temperature stress influence. The calculation parameters of the main cushion cap with dimension of 113.75 m long, 48.1 m wide, and 13.3m high are determined. Comparison is made between the monitoring value and calculated results, which are obtained by simulation analysis of thermal stress variation during concrete hardening. The analysis shows that rational controlling temperature standard, cooling with cold water pipes, and curing in time play an important role in cracks protection. The dangerous age and the location where cracks could occur are given. These could provide valuable a reference for the design and construction of the other similar projects.