内置式锚箱索塔锚固区索力水平分力分配机理研究  

Horizontal Force Distribution Mechanism of the Cable Force in the Cable-Pylon Anchorage Zone with Built-in Anchor Box

作　　者：秦国璋 戴晓春[2] 赵骏铭 肖林[1] 卫星[1] QIN Guozhang;DAI Xiaochun;ZHAO Junming;XIAO Lin;WEI Xing(School of Civil Engineering,Southwest Jiaotong University,Chengdu 610031,China;China Railway Eryuan Engineering Group Co.,Ltd.,Chengdu 610031,China)

机构地区：[1]西南交通大学土木工程学院,成都610031 [2]中铁二院工程集团有限责任公司,成都610031

出　　处：《建筑钢结构进展》2024年第8期60-67,共8页Progress in Steel Building Structures

基　　金：国家重点研发计划项目(2022YFB3706703)。

摘　　要：索塔锚固区的受力分析通常采用实体有限元单元进行,然而由于其结构复杂、种类繁多,不易被一般工程设计人员使用。为此,结合某斜拉桥的实际工程案例,分析了内置式钢锚箱锚固体系的传力特点,提出了一种基于平面框架理论的简化计算方法,并利用非线性的分析方法建立了锚固区ANSYS有限元模型以修正公式。结果表明修正前简化公式计算结果与有限元模型计算结果之间的误差在10%左右;考虑到塔壁厚度、索塔计算高度以及锚箱侧板厚度的影响,使用折减混凝土弹性模量的方法来补偿和修正桥塔应力分布,具体的混凝土折减系数使用非线性回归的方法确定。最终将修正公计算式结果与有限元模型计算结果重新进行对比,结果表明,修正后的计算公式与有限元模型计算结果的误差在2%以内,可以较好地分析索塔锚固区的索力分配情况,具有实际工程意义。The stress analysis of the cable-pylon anchorage zone is usually calculated using solid finite elements.However,due to the complex structure and diverse types,it is not easy for general engineering designers to use.Therefore,this paper analyzed the transmission characteristics of the built-in steel anchor box anchoring system based on the actual project of a cable-stayed bridge and proposed a simplified calculation method based on the plane frame theory.Nonlinear analysis methods were used to establish an ANSYS finite element model of the anchorage zone to correct the formula.The results show that the error between the calculation results of the simplified formula before correction and the finite element model calculation results is about 10%.Considering the influence of the thickness of the pylon wall,the calculation height of the pylon,and the thickness of the anchor box side plate,the method of reducing the elastic modulus of concrete is used to compensate and correct the stress distribution of the bridge pylon,and the specific concrete reduction coefficient is determined by the method of nonlinear regression.Finally,the corrected formula was compared with the finite element model data.The results show that the error between the calculation results of the corrected formula and the finite element model calculation results is within 2%,indicating the corrected formula can well analyze the cable force distribution in the cable-pylon anchorage zone and has a certain practical engineering value.

关 键 词：斜拉桥 钢锚箱 索塔锚固区 有限元方法 简化计算 

分 类 号：U448.29[建筑科学—桥梁与隧道工程]