钢筋半套筒灌浆连接的高温静力拉伸性能

Static Tensile Behavior of Half Grout Sleeve Splicing of Rebars Under High Temperature

对12个钢筋半套筒灌浆连接试件在高温下进行了静力拉伸试验,并将12根同批次钢筋在同条件下进行试验作为参照.研究了温度对钢筋半套筒灌浆连接的影响,以及钢筋半套筒灌浆连接与钢筋在高温下力学性能的差异.结果表明:半套筒灌浆连接试件在高温下的极限抗拉强度与钢筋相近,试件破坏形式为钢筋被拉断、钢筋刮犁式拔出两种;钢筋半套筒灌浆连接在200℃及以下温度条件下与钢筋单向拉伸的本构关系相似,在400℃及以上温度条件下其力学性能与钢筋存在一定差异;在常温及400℃高温下,试件的破坏模式均为钢筋被拉断,在600℃高温下半套筒灌浆连接灌浆段钢筋可能先被拨出,而非拉断.

The static tensile test was carried out for 12 half grout sleeve splicing of rebars specimens under high temperature,and 12 steel bars in the same batch were tested as control group under the same conditions.The influence of the temperature on the specimens and the mechanical property difference between the specimens and the steel bars under high temperature were studied.The test results show that the ultimate tensile strength of the specimens is similar to that of the steel bar under high temperature,and the failure modes of the specimens are the tensile rupture of rebars and the pulling-out of rebars.The tensile behaviors of the specimens are similar to the constitutive relations of uniaxial tension of the steel bars at temperatures of 200℃and below,while the mechanical pro-perties of the specimens is different from those of the steel rebars at temperatures of 400℃and above.The failure modes of the specimens at room temperature and 400℃are both tensile rupture of rebars.At 600℃,the rebars of the specimens may be pulled out first,rather than be ruptured.