摘要
提出了新型波形钢腹板-双管弦杆-混凝土板组合梁,混凝土顶板与双钢管混凝土下弦杆由波形钢腹板连接。为了分析新型组合梁在正、负弯矩作用下的受弯性能,进行了组合连续梁的受弯试验,研究了试验梁的破坏模式、变形特性、应变特性与混凝土顶板裂缝发展规律。根据试验结果,提出了新型组合梁的变形和承载力计算方法,并验证了方法的有效性。试验结果表明:在正、负弯矩区段,组合截面波形钢腹板各测点纵向应变很小,跨中和支点处纵向应变峰值仅为下弦杆的3.7%和5.1%,可忽略不计;混凝土顶板和钢管混凝土下弦杆纵向应变沿截面高度方向基本呈线性变化,满足平截面假定,在外荷载作用下共同受力;当组合试验梁达到开裂荷载140kN时,主梁跨中挠度理论计算值为5.8mm,试验值为5.5mm,误差约为5%,当组合试验梁跨中截面达到极限抗弯承载力时,荷载理论计算值为399kN,试验值为415kN,试验值略高于理论计算值,但两者误差很小,约为4%,说明该组合梁的挠度和抗弯承载力理论计算方法简单、可靠。
A new composite structure composed of corrugated steel webs （CSW）, double concrete filled steel tubular chords （CFST） and concrete slabs （CS） was presented. To understand the flexural behaviors under positive and negative bending moments, the experiments of new composite continuous box-girder were carried out, and the failure modes and deflection patterns of the girder, and the development rules of concrete plate cracks were studied. According to the test results, the calculation methods of deformation and bearing capacity of the new type of composite girder were put forward and verified. Experimental result shows the strain peak values of mid-span and intermediate support are only 3. 7% and 5. 1% of the value of bottom steel concrete pipe chord respectively, therefore the longitudinal strains of corrugated steel webs are small and negligible in the positive and negative bending moment areas. The longitudinal strains linearly change along the height of cross section, thus the plane cross-section assumption can be applied in the composite girder. Moreover, the top concrete flange and the bottom steel concrete pipe chord bear load together. When the cracking load is 140 kN, the calculated and experimental deflection are 5.8 mm and 5.5 mm, respectively, and the relative error is about 5%. When the load of mid-span cross section of test beam reaches the ultimate flexural capacity, the theoretical and experimental load are 399 kN and 415 kN, respectively, the experimental value is slightly higher than the calculated value, but the error is very small and about 4%, so the theoretical calculation methods of deflection and flexural capacity of composite beam are simple and reliable. 2 tabs, 23 figs, 25 refs.
出处
《交通运输工程学报》
EI
CSCD
北大核心
2016年第3期35-45,共11页
Journal of Traffic and Transportation Engineering
基金
教育部新世纪优秀人才支持计划项目(NCET-13-0737)
