折叠网架结构变形-荷载随机过程概率预测模型

Stochastic probability forecasting model for deformation-loads on foldable space trusses

节点位移的控制是折叠网架结构正常使用的关键。根据概率理论和数理统计原理建立二维连续型随机变量位移和荷载的概率预测模型,基于有限的试验数据,进行不同雪荷载工况下节点位移的预测。计算结果表明:100,120,140mm厚雪荷载作用时,节点竖向位移和水平位移预测值与试验测试值吻合较好,所有节点平均预测精度大于或等于97.0%;分析了边跨节点和120mm厚雪荷载作用下的节点位移预测值与实测值偏差较大的原因;120mm厚雪荷载作用时的节点位移应格外关注;相邻两级荷载的比值大于0.8是模型适用的条件。

Node displacement control is the key for normal use of foldable space trusses. A stochastic probalility forecasting model of two dimensional continuous random variables on deformation and load was proposed based on probability and mathematical statistics. Node displacement at different snow load level was predicted according to this model by using limited test data. The calculation results show that nodes vertical displacement and horizontal displacement prediction values have good agreement with test results during snow load of 100,120,140 mm thickness,the mean prediction accuracy of all nodes displacement is greater than or equal to 97. 0%. There is a slight difference between displacement prediction value and test value in the nodes of edge cross and when the load is 120 mm snow thickness and the causes of phenomena were analyzed and explained,so it is important to give an extra attention to nodes when the load is120 mm snow thickness.The model in condition of adjacent two level loads ratio greater than 0. 8 is in common use.