摘要
邻近堆卸载会对桥梁桩基造成不利影响,严重时将影响铁路的运行质量和安全,本文以一受邻近煤矿开采影响产生偏移的大桥为例予以分析。实测桥梁周边山体卸载引起的地基推移和桥梁桩基的变形,以此为基础建立有限元模型进行多角度数值分析,得出地基推移、对称堆载、不对称堆载及不同堆载高度对桩基沉降、变形和最大主应力的影响。计算结果表明,以混凝土允许主拉应力为控制指标,该桥梁桩基均匀堆载高度最大不能超过13 m,不对称堆载高度最大不能超过7 m。研究结果为维护整治提供了技术支持。
Surcharge and unloading adversely affect bridge pile foundation, even threatening the quality and safety of railway operation.In this paper,the engineering background is a bridge being subjected to displacement due to coal mining.The foundation displacement and the bridge pile deformation induced by the unloading of adjacent mountain are measured. A finite element model is built for multiple numerical analysis. The influences of foundation displacement, symmetric/asymmetric surcharge and surcharge height on pile settlement,deformation and maximum principle stress are analyzed.The results show that the uniform surcharge height should be not greater than 13 m and the asymmetric surcharge height should be not greater than 7 m based on the concrete allowable principle tensile stress.It provides technical support for maintenance.
引文
[1]陈福金,杨敏.地面堆载作用下邻近桩基性状的数值分析[J].岩土工程学报,2005,27(11):1286-1290.
[2]李国和,许再良,孙树礼,等.华北平原地面沉降对高速铁路的影响及其对策[J].铁道工程学报,2007,24(8):7-12.
[3]王军,马学宁.堆载作用下桩基受力特性分析[J].铁道建筑,2018,58(9):72-75.
[4]倪恒,刘翔宇,刘飞成.河道开挖和弃土堆载对邻近高速铁路桥梁的影响分析[J].铁道建筑,2017,57(8):28-32.
[5]代恒军,梁志柠,赵军,等.地面堆载作用下邻近桩基变形的三维数值分析[J].岩土工程学报,2010,32(增2):220-223.
[6]董亮.侧向堆载引起既有铁路桥梁桩基沉降变形的有限元分析[J].铁道建筑,2017,57(5):7-9.
[7]梁育玮,边学成,董亮.侧方堆载作用下高架桥群桩基础变形分析[J].铁道建筑,2017,57(9):5-12.
[8]国家铁路局.高速铁路设计规范:TB 10621—2014[S].北京:中国铁道出版社,2014.
[9]中华人民共和国铁道部.铁路桥涵钢筋混凝土和预应力混凝土结构设计规范:TB 10002. 3—2005[S].北京:中国铁道出版社,2005.