丽香铁路达落双线中桥增设棚洞结构设计  

作　　者：李贵民[1] 郭永发[1] 丁文云[1] 王化武 

机构地区：[1]中铁二院昆明勘察设计研究院有限责任公司,昆明650200 [2]中国铁路昆明局集团有限公司,昆明650200

出　　处：《科技创新与应用》2024年第10期126-129,共4页Technology Innovation and Application

基　　金：云南省科技厅科技计划项目(202303AA080003)。

摘　　要：该文以在建丽香铁路蒙古哨隧道出口与七达里隧道进口间达落双线中桥为工程依托,根据地形地质、落石重量、坡面高差、结构跨度及防护等级等基本情况,分析常规明洞、柔性钢网棚洞、拱桥棚洞、纵向刚架棚洞及横向刚架棚洞各自适用条件,选用合理的棚洞型式及结构尺寸。研究结论表明,对隧道坡面危岩落石重量及高差进行详细的调查分析,是确定采用柔性钢网棚洞还是钢筋砼刚性棚洞的前提。钢筋砼刚性棚洞沿线路方向跨度、冲沟排洪要求及基岩完整程度,是确定刚性棚洞具体类型的关键。落石冲击强度选用路基手册计算法较为合适,落石冲击力按移动荷载考虑,移动步距按2 m考虑为宜。棚洞结构内力及构件尺寸计算时,按落石不同位置的弯矩包络图最不利工况考虑。Based on the middle bridge between the exit of Menggushao Tunnel and the entrance of Qidali Tunnel on Lijiang-Shangrila Railway,this paper analyzes the applicable conditions of conventional open tunnel,flexible steel mesh tunnel,arch bridge tunnel,vertical rigid frame tunnel and horizontal rigid frame tunnel according to the basic conditions of terrain and geological conditions,rock fall weight,slope elevation difference,structural span and protection grade.We selected reasonable shed type and structure size.Conclusion,the detailed investigation and analysis of the weight and height difference of the dangerous rock fall on the tunnel slope is the premise of deciding whether to use the flexible steel mesh shed or the reinforced concrete rigid shed.The span of road direction along the reinforced concrete rigid shed tunnel,the requirements of flood drainage and the integrity of bedrock are the key to determine the specific type of rigid shed tunnel.It is more appropriate to choose the calculation method of the roadbed manual for the rock fall impact strength.The rockfall impact force is considered according to the moving load,and the moving step is considered according to 2 meters.When calculating the internal force and component size of the shed structure,the most unfavorable working conditions should be considered according to the bending moment envelope diagram of different positions of the falling rock.

关 键 词：V型冲沟 增设棚洞 落石冲击 移动步距 丽香铁路 

分 类 号：U25[交通运输工程—道路与铁道工程]