摘要
通过建立双层悬索结构形式之一的伞状结构的简化分析模型,运用能量原理,分别计算并列式和轮辐式伞状全张力结构在活荷载和风荷载作用下的总势能,根据势能驻值原理,对结构势能求偏导并将其结果进行简化,推导求得结构位移解析表达式,并迭代计算结构跨中压杆处位移、上索最大变形和索力。通过算例对比结构位移解析计算与有限元分析的结果,其误差较小。研究结果表明:在活荷载作用下,跨中压杆处位移、上索最大变形与荷载基本成线性关系;在风荷载作用下,跨中压杆处位移随预应力基本呈线性变化,而上索最大变形则具有较强的非线性。提出的解析计算式在矢跨比和垂跨比小于1/8时精度较高,可供结构初步设计时参考。
The simplified model for umbelliform tensegrity cable structure was established in this paper. The total potential energy of both parallel and wheel-shaped tensile structures were calculated under live load and wind load based on energy principles. According to the principle of stationary potential energy,the energy of structure was calculated and the equation was simplified. Then the displacement formula was put forward. After designing proper iteration method,the displacement of overall midspan,cable midspan and final cable force can be calculated. Through different examples,the error between calculation results of the finite element method and the displacement of overall midspan and cable midspan are proved to be very small. The research shows that under different live load levels,the displacement of overall midspan and cable midspan are in linear relationship with load. Under the same wind load,cable midspan is in linear relationship with prestress level but in nonlinear relationship with overall midspan. The formulas are concise and of clear mechanical concept. The formulas are accurate and reliable under the condition that the rise-to-span ratio and sag-to-span ratio are smaller than 1 /8. The formulas can be the reference for preliminary design.
出处
《建筑结构学报》
EI
CAS
CSCD
北大核心
2014年第9期131-140,共10页
Journal of Building Structures
基金
"十二五"国家科技支撑计划(2012BAJ03B06)
关键词
伞状结构
张力结构
势能驻值原理
解析解
umbelliform cable structure
tensile structures
principle of stationary potential energy
analytical solution
