掺锂渣再生混凝土梁斜裂缝宽度试验研究

Experimental study on widths of diagonal cracks of doped lithium slag recycled aggregate concrete beams

设计并制作9根变量因素为锂渣掺量和再生粗骨料取代率的混凝土受剪梁,对其开裂荷载和斜裂缝宽度进行分析。结果表明:掺锂渣再生混凝土梁的受剪破坏形态和裂缝分布情况与普通混凝土梁相似。荷载相同时,斜裂缝宽度随锂渣掺量和再生粗骨料取代率的提高而减小,且锂渣对其抑制作用更明显。采用普通混凝土梁斜截面开裂荷载公式[8],计算掺锂渣再生混凝土梁斜截面开裂荷载偏不安全,乘以一个调整系数0.87后可以满足其计算。根据试验梁的数据,拟合出适用于掺锂渣再生混凝土受剪梁斜裂缝最大宽度的计算公式,且其计算结果与实测结果吻合较好。

9 concrete shear beams with different ratios of recycled coarse aggregate and lithium slag content are designed,and the cracking load and the slanting crack width are analyzed.The results show that the shear failure behavior and the distribution of cracks are similar to those of ordinary concrete beams.Under the same load,the diagonal crack width decreases with the increase of the content of lithium slag and recycled coarse aggregate,and the inhibition effect of lithium slag is more obvious.The cracking load of doped lithium slag recycled aggregate concrete beams oblique section is calculate by using the formula of the concrete beam oblique section cracking load[8],and the trend unsafe can be satisfied by multiplying the adjustment coefficient by 0.87.According to the data of the test beam,the formula for calculating the diagonal crack width of the doped lithium slag recycled aggregate concrete shear beams is fitted,and the calculate results are in good agreements with the measured results.