【摘要】 通过横向预应力混凝土梁预应力损失的试验研究,考察了采用10.9级高强螺栓作为横向预应力筋时各项预应力损失的大小。得到以下主要结论:(1)管道摩擦预应力损失量占张拉控制应力的3%~5%;张拉端钢垫板变形、高强螺杆回缩和接缝压缩引起的预应力损失量占张拉控制应力的1%~3%;混凝土弹性压缩引起的预应力损失量占张拉控制应力的1%~3%;长期预应力损失占张拉控制应力的12%左右;(2)有限元分析结果表明每根高强螺栓张拉的影响范围大致为900mm;(3)提出了各项预应力损失的计算公式。更多还原

【Abstract】 Experimental study on the prestress losses of transversely prestressed concrete beams when using high strength bolts of grade 10.9 as transverse prestressing bars was carried out,and the following conclusions can be drawn:(1) the prestress losses caused by pipe friction reached 3%~5%of the tension control stress;the prestress losses caused by the deformation of steel pad,the bolt shrinkage and the compression of the joint reached 1%~3%of the tension control stress;and the prestress losses caused by elastic compression of concrete reached 1%~3%of the tension control stress;otherwise the long-term prestress losses reached 12%of the tension control stress.(2) the FEM analysis result shows that the influence scope of each tensioned high strength bolt is 900 mm.(3) the formulas to compute the prestress losses when using high strength bolts of grade 10.9as transverse prestressing bars were suggested.更多还原