MgO掺量对碾压混凝土拱坝抗裂性能的影响

Influence of MgO content on crack resistance of roller compacted concrete arch dam

为了促进外掺MgO混凝土的推广应用,对MgO掺量对碾压混凝土拱坝抗裂性能的影响进行了试验研究和仿真分析。结果表明,随着MgO掺量的增加,混凝土的自生体积变形呈增大趋势,碾压混凝土拱坝的最大主拉应力下降,大坝的抗裂性能得到改善;对于本试验所用的粉煤灰混凝土,若适当提高混凝土的MgO外掺量,有可能全面抵消混凝土的拉应力或补偿混凝土的温降裂缝。

To accelerate application of magnesium oxide concrete ,the influence of MgO content on crack resistance of roller compacted comcrete arch dam was tested and simulated.The results show that the autogenic volume change was bigger,the maximal tensile stress of roller compacted comcrete arch dam was decreased and the crack resistance of the dam was improved with MgO content increasing.The fly ash concrete used for the test, could it be possible to fully offset the tensile stress of concrete or compensate for the temperature drop cracks of the concrete by increasing in the MgO content of concrete.