新型不锈钢波纹板抗弯力学特性试验与数值分析

Experimental and Numerical Study on Flexural Mechanical Properties of New Stainless Steel Corrugated Plate

为探究新型S32001双相不锈钢波纹板结构在隧道加固领域的优势,开展新型不锈钢波纹板与Q235碳素钢波纹板的纯弯加载试验,对比分析二者的力学响应,建立与试验对应的三维精细化有限元模型,验证模型的合理性并开展敏感性分析。结果表明:(1)Q235碳素钢波纹板跨中最大弯矩为11.8 kN·m,新型不锈钢波纹板跨中最大弯矩为15 kN·m,其承载性能优于Q235碳素钢波纹板,且刚度更高,延性更强。(2)Q235碳素质钢波纹钢板加载过程中弹性变形阶段的截面应变符合平截面假定,进入塑性阶段后因波纹板波谷产生较大塑性应变而不再符合;新型不锈钢波纹板加载全过程截面应变均基本符合平截面假定。(3)新型不锈钢波纹板的跨中抗弯刚度和极限承载力随轴力的增大而增大,N=100 k N时的跨中极限弯矩比N=0 kN时的提高28.6%。

In order to explore the advantages of new S32001 duplex stainless steel corrugated plate structure in the field of tunnel reinforcement,pure bending loading tests are conducted on a new type of stainless steel corrugated plate and the Q235 carbon steel corrugated plate.The mechanical responses of the two plates are compared and ana⁃lyzed,and a 3D refined finite element model corresponding to the test is established to verify the rationality of the model and carry out sensitivity analysis.The results show that:(1)The maximum mid-span bending moment of the Q235 corrugated plate is 11.8 kN·m,and the maximum mid-span bending moment of the new stainless steel corru⁃gated plate is 15 kN·m.The bending and load-bearing performance of the new stainless steel corrugated plate is better than that of the carbon structural steel corrugated plate,with higher stiffness and stronger ductility.(2)The section strain during the elastic deformation phase of the Q235 corrugated steel plate in the process of loading con⁃forms to the plane cross-section assumption,but after entering the plastic phase,it no longer conforms due to the large plastic strain generated by the trough of the corrugated plate.The strain distribution along the height on the mid-span section of the new stainless steel corrugated plate basically conforms to the plane cross-section assump⁃tion.(3)The mid-span bending stiffness and the ultimate bearing capacity of the new stainless steel corrugated plate increase with the rise of axial force.When N=100 kN,the mid-span ultimate bending moment of the new stainless steel corrugated plate is 28.6%higher than that when N=0 kN.