悬臂混凝土薄壁箱梁剪力滞效应试验研究与分析

进行了大比例伸臂混凝土薄壁箱梁在弹性范围内的剪力滞效应试验研究与分析,重点研究了伸臂混凝土薄壁箱梁悬臂部分在不同荷载作用下,荷载-挠度曲线以及不同截面处翼缘混凝土应变分布规律等问题.研究结果表明:在集中荷载作用下不同位置处截面均存在正剪力滞现象;而在均布荷载作用下不同位置处截面存在不同的剪力滞现象:支座处存在正剪力滞现象,离支座2/3悬臂长度处存在明显的负剪力滞现象.根据试验结果,得到了伸臂混凝土薄壁箱梁悬臂部分不同荷载作用下,不同截面处翼缘等效宽度计算系数,并和现行JTG D62-2004规范比较,得出规范计算结果较试验结果偏于安全.

Experimental Research and Analysis on the Shear Lag Effect of High- Strength Concrete Thin- Walled Box Continuous Girder

The experimental research and analysis on shear lag effect of the concrete thin-walled box cantilever girder have been performed in elastic stage.The deflection and concrete strain distribution of the flanges in different sections and different loads have been studied.The results demonstrate that the positive shear lag phenomenon have been confirmed in different sections under concentrated loads,but the different shear lag phenomenon have been confirmed in different sections under uniform loads: positive shear lag phenomena in support section,negative shear lag phenomena in 2/3 cantilever long section.The experimental values of equivalent calculated coefficient of flange width in different sections have been given under different loads.Compared with calculating values by the code(JTG D62-2004),the calculated value is confirmed to safe in support section.