铁路预应力混凝土梁不同张拉工艺的静载弯曲试验研究

Research on Static Load Bending Test of Railway Prestressed Concrete Beams with Different Tensioning Techniques

预应力张拉施工作为铁路预应力混凝土预制梁生产的控制性工作,其张拉工艺至关重要。传统人工张拉具有精度低、同步性差、操作复杂等缺点,而智能张拉具有高精度、全自动等优势。静载弯曲试验是梁体施加预应力效果的主要检验标准,也是检验梁体质量最直接、最根本的方法。为对人工张拉和智能张拉两种工艺下的张拉质量进行检验,本研究拟对两组不同方法张拉的试验用梁分别进行静载弯曲试验,并进行有限元数值分析。结果表明:经过人工张拉和智能张拉的试验梁静载弯曲试验各项评定指标均合格;与人工张拉相比,采用智能张拉的试验梁静载弯曲试验各加载级实测梁体挠度和钢束张拉力更接近理论计算值,较人工张拉梁张拉控制精度更高,张拉质量更优。

As the controlling work in the production of railway prestressed concrete precast beams,the tensioning techniques of prestressed concrete construction become particularly important.Traditional manual tensioning has drawbacks such as low accuracy,poor synchronization,and complex operation,while intelligent tensioning has advantages of high precision,full automation,etc.The static load bending test is the main test standard for the effect of prestressing the beam body,and it is also the most direct and fundamental method for testing the quality of the beam body.In order to check the tensile quality under both manual tensioning and intelligent tensioning processes,this study intends to carry out static load bending test on two groups of test beams with different tensioning methods,and conducts finite element numerical analysis.The results show that all the evaluation indexes of static load bending test of the test beam after manual tensioning and intelligent tensioning are qualified.Compared with manual tensioning,the measured beam body deflection and steel tendon tensile force at each loading stage of the beam static load bending test using intelligent tensioning are closer to the theoretical calculation values,and the tensioning control accuracy and tensioning quality are higher than those of manual tensioning beam.