论文部分内容阅读
基于国产高强钢Q550D和TQ700MCD的材料性能试验结果,对窄翼缘和宽翼缘两种截面形式的高强焊接工字钢开孔梁进行受弯试验研究。主要研究试件的破坏形态、抗弯承载力、弯矩曲率、应变分布等,探讨窄翼缘和宽翼缘两种截面形式分别在两种弯曲状态下,孔洞参数对试件受弯性能的影响,并比较三点弯曲试验和四点弯曲试验下试件极限承载力的大小。试验结果表明:试件的典型破坏形式为受压翼缘板发生局部屈曲,屈曲半波长度与翼缘宽度相当。对于窄翼缘截面梁,在两种弯曲状态下,当开设孔洞的径高比为0.3时,孔洞的存在对试件的极限承载力影响都较小;当径高比为0.6时,四点弯曲试件的极限承载力比三点弯曲试件的极限承载力下降显著。对于宽翼缘截面梁,在两种弯曲状态下,当开设孔洞的径高比为0.3时,孔洞数目的增加对试件极限承载力的影响较小。开孔试件由于孔洞的存在,导致应力重分布,使试件的极限承载力有不同程度的下降,但下降幅度与开设孔洞的参数紧密相关。
Based on the material property test results of domestic high-strength steel Q550D and TQ700MCD, the bending test of two kinds of high-strength welded I-beam open-ended beams with narrow flanges and wide flanges was carried out. Mainly study the failure morphology, flexural capacity, moment curvature and strain distribution of the specimens, and explore the influence of the parameters of the holes on the flexural properties of the specimens under two kinds of bending states And compare the three-point bending test and four-point bending test under the ultimate bearing capacity of the specimen size. The experimental results show that the typical failure mode of the specimen is local buckling of compression flange plate, and the buckling half-wave length is equivalent to the flange width. For a narrow flange section beam, under the two bending conditions, when the diameter-height ratio of the hole is 0.3, the influence of the hole on the ultimate bearing capacity of the specimen is small. When the height-to-diameter ratio is 0.6, The ultimate bearing capacity of the bent specimens decreased significantly compared with that of the three-point specimens. For the beam with wide flanges, the increase of the number of holes has little effect on the ultimate bearing capacity of the specimens under the two bending conditions when the ratio of the diameter of the holes is 0.3. Due to the presence of holes, the stress distribution in the open-hole test specimen leads to the decrease of the ultimate bearing capacity of the test specimen, but the decrease is closely related to the parameters of the opening hole.