极限状态法和容许应力法对高架车站轨道梁设计的影响分析
|
摘要
按目前规范的要求,轨道交通高架车站结构需要采用极限状态法和容许应力法两种不同的方法进行计算。设计人员对这两种方法的本质及计算结果的差异往往缺乏足够的认识。为厘清两种方法对设计结果的影响,以钢筋混凝土轨道梁为研究对象,对两种计算方法的计算结果进行比较分析。另外,对规范给出的基本公式进行推导,以期得到适用性更广泛的结论。结果表明,容许应力法的计算结果更为保守。计算结果的差异与配筋率和材料强度有关,当配筋率较大时,计算结果差异随配筋率增大而增大;当钢筋强度不变时,计算结果差异随混凝土强度的增大而减小。研究成果有利于简化高架车站轨道梁等受弯构件的设计,同时也为将来铁路规范的修订提供参考。
According to current codes,the elevated station structure of rail transit needs to be designed with two different methods: the limit state method and the allowable stress method. Engineers usually lack sufficient knowledge about the essence of the two methods and the calculation difference derived from them. To find out how these two methods influence the design,they are applied to reinforced concrete track beam and the results are compared and analyzed. In addition,the fundamental equations in codes are used to obtain more widely applicable conclusions. The result reveals that the allowable stress method is more conservative. The differences in calculation results are related to reinforcement ratio and material strength. When reinforcement ratio is at a higher level,the differences increase. When rebar strength is constant,the difference decreases as concrete strength increases. The conclusions are helpful in simplifying the designing of bending members such as track beams,and provide references for the revision of railway codes.
According to current codes,the elevated station structure of rail transit needs to be designed with two different methods: the limit state method and the allowable stress method. Engineers usually lack sufficient knowledge about the essence of the two methods and the calculation difference derived from them. To find out how these two methods influence the design,they are applied to reinforced concrete track beam and the results are compared and analyzed. In addition,the fundamental equations in codes are used to obtain more widely applicable conclusions. The result reveals that the allowable stress method is more conservative. The differences in calculation results are related to reinforcement ratio and material strength. When reinforcement ratio is at a higher level,the differences increase. When rebar strength is constant,the difference decreases as concrete strength increases. The conclusions are helpful in simplifying the designing of bending members such as track beams,and provide references for the revision of railway codes.
引文
[1]中华人民共和国住房和城乡建设部.GB 50157—2013地铁设计规范[S].北京:中国建筑工业出版社,2013.
[2]高策,薛吉岗.铁路桥梁结构设计规范由容许应力法转换为极限状态法的思考[J].铁道标准设计,2012(2):41-45.
[3]钱冬生.用极限状态原理修订《铁路桥涵设计规范》的若干建议[J].铁道标准设计,1988(1):10-12.
[4]钱冬生.可靠性理论与我国铁路桥梁设规的修订[J].铁道工程学报,1988(3):134-136.
[5]钱冬生.谈谈中国的铁路桥设计规范[J].桥梁建设,2009(2):9-14.
[6]钱冬生.关于将铁路桥设规的水平提高一步的思考[J].桥梁建设,2013,43(3):1-4.
[7]倪章军,曹雪琴,朱金龙.城市轨道交通桥梁按极限状态法设计的建议[J].同济大学学报(自然科学版),2003,31(10):1173-1177.
[8]朱志营,齐成龙.铁路桥梁正常使用极限状态可靠度校准研究[J].铁道标准设计,2015,59(1):80-83.
[9]中华人民共和国住房和城乡建设部.GB 50010—2010混凝土结构设计规范[S].北京:中国建筑工业出版社,2014.
[10]中华人民共和国铁道部.TB 10002.3—2005铁路桥涵钢筋混凝土和预应力混凝土结构设计规范[S].北京:中国铁道出版社,2005.
[11]中华人民共和国住房和城乡建设部.GB 50009—2012建筑结构荷载规范[S].北京:中国建筑工业出版社,2012.
[2]高策,薛吉岗.铁路桥梁结构设计规范由容许应力法转换为极限状态法的思考[J].铁道标准设计,2012(2):41-45.
[3]钱冬生.用极限状态原理修订《铁路桥涵设计规范》的若干建议[J].铁道标准设计,1988(1):10-12.
[4]钱冬生.可靠性理论与我国铁路桥梁设规的修订[J].铁道工程学报,1988(3):134-136.
[5]钱冬生.谈谈中国的铁路桥设计规范[J].桥梁建设,2009(2):9-14.
[6]钱冬生.关于将铁路桥设规的水平提高一步的思考[J].桥梁建设,2013,43(3):1-4.
[7]倪章军,曹雪琴,朱金龙.城市轨道交通桥梁按极限状态法设计的建议[J].同济大学学报(自然科学版),2003,31(10):1173-1177.
[8]朱志营,齐成龙.铁路桥梁正常使用极限状态可靠度校准研究[J].铁道标准设计,2015,59(1):80-83.
[9]中华人民共和国住房和城乡建设部.GB 50010—2010混凝土结构设计规范[S].北京:中国建筑工业出版社,2014.
[10]中华人民共和国铁道部.TB 10002.3—2005铁路桥涵钢筋混凝土和预应力混凝土结构设计规范[S].北京:中国铁道出版社,2005.
[11]中华人民共和国住房和城乡建设部.GB 50009—2012建筑结构荷载规范[S].北京:中国建筑工业出版社,2012.