承台及桥墩大体积混凝土温度与应力场控制研究

Research on Control of Temperature and Stress Field of Mass Concrete of Pile Caps and Bridge Piers

建立了廊涿城际铁路某桥梁承台及桥墩大体积混凝土有限元模型,通过分析不同保温条件下的温度场,获得了合适的保温方式;通过分析冷却管不同的通水方案,获得了合适的降温方式。进一步研究了承台及桥墩的温度场变化规律,并与现场实测值进行了对比分析,表明采用Midas FEA模拟大体积混凝土温度场效果较好。通过分析应力场分布,获得了温度裂缝指数分布情况,进而揭示了承台及桥墩温度裂缝易开展的位置。研究成果有助于现场对于温度裂缝采取针对性的控制措施。

This paper established a large-volume concrete finite element model of a bridge cap and pier of the Lang-Zhuo Intercity Railway.By analyzing the temperature field under different heat preservation conditions,a suitable heat preservation method was obtained;and the cooling method was obtained by analyzing different water supply schemes of cooling pipe.The change law of the temperature field of the bearing platform and the bridge pier was further studied,and the comparison with the field measured value was carried out,which showed that the Midas FEA could be used to simulate the temperature field of mass concrete.By analyzing the stress field distribution,the exponential distribution of temperature cracks was obtained,and the locations where temperature cracks easy to develop on the cap and pier were revealed.The research results help to take targeted control measures for temperature cracks on site.