整体式桥的桥身与桥台之间没有设置支座和伸缩缝,而是刚性连接为一体,从而能极大地节省桥梁全寿命周期的维护与维修费用。但是由于季节性温度波动导致桥身长度变化,桥台后土体随之受到水平方向循环加载作用。桥台后土压力的发展变化,成为整体式桥研究的重点。另外,对整体式桥台在地震作用下的动力反应还缺乏认识。该文首先系统总结了关于整体式桥台后土压力的相关研究成果,包括现场监测、缩尺模型实验、土单元应力路径实验、以及数值模拟等,揭示出在这种特殊循环作用下桥台后土压力的变化规律,并对土压力累积机理进行了探讨。然后,该文总结了整体式桥台在地震作用下动力响应的相关研究成果,指出由于桥台与桥身的刚性连接,桥身惯性力对桥台与土动力相互作用产生很大影响。
Integral bridges have no bearings or joints between the decks and abutments, thus they can significantly reduce bridge life-time costs. However, the soil behind the abutment is subjected to cyclic loading from the abutment as the deck length varies due to annual temperature variations. Great uncertainties have arisen about the ultimate magnitude of the lateral earth pressure behind integral abutments. This paper summarizes the researches related to integral abutments, including field monitoring, small-scale testing, stress path testing, and numerical modeling. It is revealed that the soil pressure will continue to increase with the cycling actions, and the mechanism has been discussed. The researches related to the dynamic behavior of integral abutments are also summarized. Due to the integral connection, the inertia force of the deck imposes a significant influence on the seismic interaction between the abutment and soil.