轨道交通车辆基地网架结构设计要点分析

Analysis on Structural Design Points of Space Grid in Rail Transit Vehicle Base

车辆基地厂房的工程造价占基地总工程费用比重较大,其结构设计直接影响到车辆基地工程造价的经济性,为保证厂房结构安全、适用、经济,对轨道交通车辆基地厂房常用结构形式进行对比分析,选择目前常用的网架结构作为研究对象,分析支撑柱距、网格尺寸、简支或连续的选择、结构找坡、端部高度对其用钢量的影响,并对计算模型的选择进行分析。分析结果表明:车辆基地网架屋盖选用9 m支撑柱距、较大的网格尺寸、连续网架结构起坡排水、网架端部高度取其跨度的1/15~1/20时,结构经济合理、用钢量小;实际工程中可采用等代梁或等效弹性板法模拟网架结构;目前常用工程设计软件已有条件建立混凝土结构与网架的整体模型,此模型可准确反映网架与下部支撑结构的整体协同作用,计算结果更符合工程实际,建议推广使用。

The construction cost of the plant building covers a large proportion of the total project cost of the railway transit vehicle base,which is strongly influenced by the design of the plant structure. In order to ensure its safety,serviceability and economy,the common structural forms of the railway vehicle base plant are compared and analyzed, and steel-consumption of the commonly used grid structure is determined based various impact factors such as braced column spacing; mesh size,selection between simply-supported and continuous structure,structure slope,height of the end of the structure,and selection of its calculation model. The results show that the vehicle base grid roof is designed with 9 m support column,large grid size,structure slope of continuous truss,the ratio of height to span between 1/15 ～ 1/20 is reasonable and economical with less steel-consumption; the equivalent beam or equivalent elastic plate method can be used to analyze the interaction between the grid roof and braced reinforced concrete structure in practical engineering,; at present,the general engineering design software is able to build calculation model of concrete structure with space grid to accurately indicate the interaction between the grid roof and braced reinforced concrete structure. The calculation results are applicable for practical application and can be widely used.