基于预应力度的大型预应力混凝土筒仓设计

Design of Large Prestressed Concrete Silos Based on the Degree of Prestress

为科学合理地调节预应力混凝土筒仓配筋中预应力筋与非预应力筋的比例,提出了基于预应力度的预应力混凝土筒仓设计方法,对预应力度的合理取值进行了探讨.预应力设计计算和有限元分析结果表明,预应力度选取时,对于筒仓底部环向拉力比较大的区段,预应力强度比λ可取为0.7;对于筒仓底部以上所受环向拉力较小的区段,预应力强度比λ可以随着所受环向拉力的减小而逐步降低;然后以初步选定的预应力强度比λ按轴心受拉构件进行配筋试算.基于预应力度的部分预应力混凝土筒仓配筋设计方法可以较好地解决预应力筋与非预应力筋的比例问题.

For the scientific and reasonable adjustment of the proportion of the prestressed rebars and non-prestressed rebars in the prestressed concrete silos ,a method to design the prestressed concrete silos based on the degree of prestress is put forward and the proper value of the degree of prestress is explored in this thesis .The analysis of prestressed design and caculation and the finite element shows that as for the selection of the degree of prestress ,the degree of prestress can be set 0 .7 for the sec-tion where the circumferential tensile force at the bottom of silo wall is relatively stronger ,while the prestress ratio λcan be steadily reduced with the decreasing of the circumferential tensile force for the section where the circumferential tensile force above the bottom of silo wall is weaker .Then the pre-liminary selected prestress ratio λ based on axial tension members can be applied to the reinforcem-ment caculation .In addition ,the reinforcement design method of prestressed concrete silos based on the degree of prestress is scientific and practical .