圆形预应力筒仓第一批预应力损失的计算方法探讨

Discussion on calculation method of prestress loss during stretching and anchoring stage in prestressed concrete silos

介绍了第一批预应力损失的计算原理,利用变形协调条件对筒仓结构预应力第一批损失进行了理论推导,对不同曲率半径的筒仓进行试算,并与常用简化计算方法进行对比。结果表明,忽略直线段反向摩擦力时,σ_(l1max)计算结果偏差较大;σ_(l 2 max)精度要求不高时,可采用广义夹角按GB 50010-2010公式近似计算。结合设计经验,总结出不同成孔方式的预应力筋在计算σ_(l1)时的θ角限值及第一批预应力损失总值的计算方法。

The calculation principle of prestress loss during stretching and anchoring stage is introduced.Based on the deformed compatibility,the prestress loss of silos is calculated theoretically.The trial results with different curvature radii based on theory method and common simplified calculation method are compared.The results show that the deviation ofσ_(l1max )calculated results is significant if the reverse friction of straight line segment is ignored.If the accuracy requirement is not high,the approximate calculation method of GB 50010-2010 can be adopt to solve σ_(l 2 max).Based on design experience,θlimit value used to solve σ_(l1) with different pore forming methods and calculation method of gross value of prestress loss during stretching and anchoring stage are summed up.