Combining with practical investigation and analysis , the author presented the fitting equation of the second non - uniform coefficient in which the method of least squares error approximation with the power index regression is used and proposed a modified formula for flow rate per second calculation to precisely determine the size of pipeline and to make the design advanced in technology and reasonable cost 本课题分析了室外和室内的设计流量公式,通过调查、实测本地区的水量资料,运用相关数学方法分析,提出了适合小区给水管网采用的流量公式。
Local buckling capacity of steel composite beam subjected to combined bending , shear and patch loading is one of key problem in steel structures design . the computational formula for local stability of web was based on the assumption of infinite - elastic perfect plates in the steel structures design code ( gbj17 - 88 ) . but in the revised code ( gb50017 - 2003 ) , this formula was made big change with reference to british code ( bs5950 , partl ) and australian code ( as4100 ) , the related research result of our country was included as well . in the modified formula , influence of early geometric imperfection and elastic - plastic buckling stage were considered , which is compatible with both actual circumstance of engineering and the strength formula of beams under bending stresses ( considering partial plasticity of the section ) . in this paper , the preceding problem is deeply analyzed and studied , considering the effects of various geometric parameters and stress combinations on buckling critical stress of web , the revised local buckling correlative formula for transverse and longituded stiffened web panels under combined stresses is analyzed and verified by finite element method 组合钢梁腹板在弯、剪及局压复合应力作用下的局部屈曲承载能力是钢结构设计中需考虑的问题,新的《钢结构设计规范》 ( gb50017 ? 2003 )对此部分内容作了较大改动,原规范中关于腹板局部稳定的计算公式是基于无限弹性的完善板假定;新的规范则参考了英国规范( bs5950 part1 )及澳大利亚规范( as4100 )并结合我国相关研究成果,考虑了屈曲进入弹塑性阶段以及初始几何缺陷的影响。这不仅与工程实际情况相符,而且也与钢梁在弯曲应力作用下允许截面部分进入塑性的计算公式相协调。