大跨度梁拱组合桥上无砟轨道板立模标高的确定及影响因素分析  

Determination of Formwork⁃erecting Elevation of Ballastless Track Slab for Long Span Girder⁃Arch Combined Bridge and Analysis of Its Influencing Factors

作　　者：王典斌[1] WANG Dianbin(China Railway Eryuan Engineering Group Co.Ltd.,Chengdu 610031,China)

机构地区：[1]中铁二院工程集团有限责任公司,成都610031

出　　处：《铁道建筑》2021年第4期152-155,共4页Railway Engineering

基　　金：四川省科技计划(2019YFG0048)。

摘　　要：以一高速铁路大跨度梁拱组合桥为例,采用数值模拟方法分析了无砟轨道板铺设过程中立模标高的确立方法,以及轨道板模拟方式、施工顺序、存梁时间等因素对无砟轨道板立模标高的影响。结果表明:采用梁单元和采用板单元模拟无砟轨道板时其预抛高值基本相同,采用梁单元或板单元模拟无砟轨道板比通过施加等效力模拟无砟轨道板重量更能满足立模标高的高精度要求;从桥梁中跨跨中向两端铺设更有利于实际施工及控制桥梁中跨无砟轨道板的预抛高值,从桥梁两端同时向中跨跨中铺设更有利于控制桥梁边跨无砟轨道板的预抛高值;随着存梁时间增加中跨无砟轨道板预抛高值逐渐减小,施工过程中应根据实际存梁时间合理预测混凝土收缩徐变对中跨无砟轨道板预抛高值的影响。Taking a high speed railway long span girder-arch combination bridge as an example,the numerical simulation method was used to analyze the method of determining the formwork-erecting elevation in the process of laying ballastless track slab,the influences of track slab simulation mode,construction sequence,girder storage time and other factors on the formwork-erecting elevation of ballastless track slab were analyzed.The results show that when girder element and plate element are used to simulate ballastless track slab,the pre-cambers are basically the same.The girder element or plate element used to simulate the ballastless track slab can better meet the high precision requirements of the formwork-erecting elevation than the equivalent force applied to simulate the weight of the ballastless track slab.Laying from the mid-span to both ends of the bridge is more conducive to the actual construction and control of the pre-camber of ballastless track slab in the mid-span of bridge.Laying from both ends of the bridge to the mid-span at the same time is more conducive to the control of the pre-camber of ballastless track slab in the side span of bridge.With the increase of bridge girder storage time,the pre-camber of ballastless track slab in the mid-span of bridge is gradually smaller.In the construction process,the influence of concrete shrinkage and creep on the precamber of ballastless track slab in the mid-span of bridge should be reasonably predicted according to the actual girder storage time.

关 键 词：大跨度梁拱组合桥 无砟轨道板 数值模拟 立模标高 预抛高值 存梁时间 施工顺序 

分 类 号：U448.13[建筑科学—桥梁与隧道工程]