方中空夹层钢管混凝土轴压短柱力学性能对比试验研究

Comparative test study on mechanical behavior of concrete-filled double-skin steel tubular with hollow-centered square section short columns under axial compression

对4种不同截面形式的钢管混凝土试件进行轴压对比试验,试件分为方实心试件、方套圆中空夹层试件和2种内管不同放置形式的方套方中空夹层试件。试验结果表明:所有试件达到极限承载力之后,均出现外管焊缝开裂、内管向内凸曲的现象;在空心率不太大的情况下,方中空夹层钢管混凝土的轴压承载力比方实心钢管混凝土大;方实心试件比方中空夹层试件的横向应变发展快,方套圆中空夹层试件比方套方中空夹层试件的横向应变发展更快;采用有限元分析软件ABAQUS对轴压试件的荷载—变形全过程进行计算,得到的极限承载力与试验结果吻合较好。

The paper carries out axial compression tests on four concrete-filled steel tubular pieces of different cross section shapes,namely solid square-shaped specimen,square specimen with circular hollow,and two square specimens with square hollow in the middle and differently placed inner tubes.The results indicate that as all the specimens reach their ultimate bearing capacity,cracked weld and buckled inner tube in all cases.In the case of the hollow rate remains at a reasonably low level,the specimen with square-shaped hollow exceeds its solid counterparts in axial bearing capacity.In terms of lateral strain,the solid square-shaped specimen develops quicker than hollowed square specimen,the square specimen with circular hollow develops more quicker than square specimens with square hollow.By using the finite element analysis software ABAQUS to calculate the loading-deformation process of the specimens under axial compression,the ultimate bearing capacity of the calculated consistent well with the test data.