孟加拉重载铁路基床设计技术研究  

Research on the Design Technique of Subgrade Bed for Heavy Haul Railway in Bangladesh

作　　者：刘孟适 蒋楚生[1] 贺钢[1] 易旭鹏 曾惜 LIU Mengshi;JIANG Chusheng;HE Gang;YI Xupeng;ZENG Xi(China Railway Eryuan Engineering Group Co.Ltd,Chengdu,Sichuan 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：《铁道工程学报》2021年第8期11-15,64,共6页Journal of Railway Engineering Society

基　　金：中铁二院工程集团有限责任公司科技研发项目(KYY201811018-20)。

摘　　要：研究目的:孟加拉帕德玛大桥连接线是连通帕德玛河东、西两岸城市的重要通道。基于孟加拉重载铁路基床结构形式和尺寸,采用列车荷载传递模式和基床结构三指标设计方法,分析适用于孟加拉国的铁路基床设计原则和流程,提出25 t轴重下重载铁路基床设计指标和填料方案。研究结论:(1)当前孟加拉本国采用的重载铁路基床设计指标与中国标准中的强度、变形和长期稳定性要求存在差异,设计安全储备和耐久性低于中国标准;(2)孟加拉重载铁路应以强度控制作为基床设计原则,保证路基各结构层承受的列车极限动荷载低于填料允许动强度,基床表层E_(v2)应大于100 MPa、基床底层E_(v2)不小于60 MPa;(3)基床表层填料采用体积掺配比70%碎砖+30%中粗砂混合料,基床底层填料采用体积掺配比35%碎砖+65%粉细砂混合料;(4)本研究成果可在孟加拉国或南亚地区重载铁路基床设计领域应用。Research purposes:The connection line of the Padma Multipurpose Bridge in Bangladesh is an important passage linking the cities on the east to those on the west banks of the Padma River.Based on the structure type and size of heavy haul railway subgrade bed in Bangladesh,this research adopted the train load-transfer mode and the three-index design method of the subgrade bed structure,for analyzing the design principles and procedures applicable to the Bangladesh railway subgrade bed.Additionally,some design indicators and filling method statement for heavy haul railway subgrade bed under 25 t axle load were proposed.Research conclusions:(1)The design indexes of heavy haul railway subgrade bed currently adopted in Bangladesh does not meet the requirements of strength,deformation and long-term stability.Furthermore,the safety storage and durability for subgrade bed are lower than the Chinese standards.(2)The strength control should be adopted as a design principle for the subgrade bed of heavy haul railway in Bangladesh,which will ensure that the ultimate dynamic load of each structural layer in subgrade bed is lower than the allowable dynamic strength of the filler.The E_(v2) of the surface layer of subgrade bed should be greater than 100 MPa,and the E_(v2) of the bottom layer of subgrade bed should not be less than 60 MPa.(3)A mixture by volume ratio of 70%broken bricks+30%medium-coarse sand should be applied for fillings on the surface layer of subgrade bed,and a mixture by ratio of 35%broken bricks+65%silty fine sand should be applied on the bottom layer of subgrade bed.(4)The research results can be applied to the area of subgrade bed design for heavy haul railway in Bangladesh or South Asia.

关 键 词：重载铁路 基床结构 强度控制 设计指标 二次变形模量 

分 类 号：U213.1[交通运输工程—道路与铁道工程]