背管分项系数设计表达式结构系数的取值研究

Study on rational structure coefficient value of partial factors design expression for steel lined reinforced concrete penstock

结合电力行业标准SD144 - 85《水电站压力钢管设计规范》的修订工作 ,对国内外背管 (钢衬钢筋混凝土压力管道 ,简称背管 )设计的安全系数取值情况进行了分析 ,认为我国现行的背管设计在安全度方面尚有潜力可挖 ,建议背管设计的安全系数可与现行规范中明管设计的安全系数相同 ,并据此推导了按工程经验校准法确定背管分项系数设计表达式中结构系数的计算公式 ,提出了背管结构系数的取值建议 。

Combining with the revised work of eletric industry standard SD 144 85 “The Design Code for Steel Penstocks of Hydropower plants”,the design safety factor of steel lined reinforced concrete penstock at home and abroad is analysed.It is considered that there is potenitial capacity to be exploited in safety limit of current design method for steel lined reinforced concrete penstock.It is recommended that the design safety factor of steel lined reinforced concrete penstock can be the same as exposed penstock in the current code.Based on this view,the formulae for calculating structure coefficient are derived in partial safety factor design expression for steel lined reinforced concrete penstock according to engineering experience calibration,and the value of correlative structure coefficeints is proposed.These research results may serve as reference for revising design code for steel penstock of hydropower station.