论文部分内容阅读
实际工程施工过程中,竖向预应力钢筋及锚垫板的定位都存在误差,导致锚垫板顶面和锚固螺母底面之间产生初始夹角θ,该夹角在竖向预应力钢筋锚固时会使钢筋回缩量增加,对竖向预应力损失影响很大。在某预应力连续刚构桥施工过程中,利用LS160-60型激光角度尺对该初始夹角θ进行测试,收集样本,采用皮尔逊Ⅲ曲线假设、矩估计法及皮尔逊χ2拟合检验法对样本分布规律进行分析,结果表明:初始夹角θ服从皮尔逊Ⅲ曲线分布。实际测试结果显示,在保证率为90%的情况下,精轧螺纹钢锚固后倾角达到3.9°,锚垫板倾角达到3.0°。预应力瞬时锚固损失最大可能会增大到原有值的1.25倍。
During the actual construction, there is an error in the positioning of the vertical prestressed steel bar and the anchor plate, resulting in an initial angle θ between the top surface of the anchor plate and the bottom surface of the anchor nut. When the angle is vertical to the prestressed steel bar, Will increase the amount of rebar reinforcement, vertical loss of prestress significant impact. During the construction of a prestressed continuous rigid frame bridge, the initial angle θ was measured by LS160-60 laser angle scale, and the samples were collected. The Pearson Ⅲ curve assumption, moment estimation method and Pearson χ 2 fitting test The results show that the initial angle θ obeys the Pearson Ⅲ curve distribution. The actual test results show that, with the guarantee rate of 90%, the angle of post-anchor rebar anchoring is 3.9 ° and the anchor plate angle of inclination is 3.0 °. Prestressed instantaneous anchor loss may increase up to 1.25 times the original value.