六四式铁路军用梁的预应力加固技术研究

为提高既有六四式铁路军用梁的承载能力,使其适应高速、重载铁路的抢修需求,以24 m跨单层六四梁为研究对象,提出5种平面内的预应力加固方案,建立有限元模型,分析加固方案和预应力大小对结构承载能力和整体刚度影响的变化规律,并与未加固的钢梁进行对比分析。结果表明:直接布索的加固方案1～3不能有效提升钢梁的承载能力,但可提升钢梁整体刚度;布索和撑杆结合的加固方案4、5可有效提升承载能力,且对整体刚度的提升明显优于直接布索的加固方案;布索和撑杆结合的加固方案中,单撑杆方案对承载能力的提升略优,双撑杆方案对整体刚度的提升略优;加固方案可能对局部杆件的稳定性产生不利影响。

Research on Prestressed Reinforcing Techniques for Type 64 Military Railway Beam

To improve the bearing capacity of the existing type 64 military railway beam, which is applied to repairing high-speed and heavy haul railway, this paper puts forward 5 prestressed reinforcing schemes based on 24 m single span beam, analyzes the variation of bearing capacity and stiffness caused by prestressing in each scheme, and compares with the unreinforced beam by establishing a finite element model. The results show that schemes 1～3 without brace fail to improve the bearing capacity effectively, but can improve the general stiffness of the beam; while, schemes 4 and 5 with brace can effectively improve the bearing capacity and are more efficient in improving the stiffness than the schemes without brace; of the schemes with brace, the single-brace scheme has better effect in improving bearing capacity, and the double-brace scheme has better effect in improving stiffness; and the reinforcement schemes may adversely affect the stability of local rods.