Influence of replacement ratios of spontaneous-combustion coal gangue aggregate on the compressive strength of concrete

Abstract To quantify the influence of coarse spontaneous-combustion coal gangue aggregate (SCGA) replacement ratio ( r c ) on the compressive strength of concrete, we reveal the deterioration mechanism of the compressive performance of spontaneous-combustion coal gangue aggregate concrete (SCGAC). 5 groups of SCGAC with different aggregate replacement ratios were designed to measure compressive strength by test, and the structures of concrete was acquired by Scanning Electron Microscope. Data reveal that as the r c rises, there is a corresponding decrease in the compressive strength of SCGAC. Compared with natural aggregate concrete (NAC), the 28 d axial compressive strength of SCGAC with the r c of 50% and 100% decreases by 14.61% and 19.40%, respectively. The Weibull distribution of SCGAC compressive strength is closer to the actual compressive strength distribution characteristics, which is more suitable for predicting the compressive strength of SCGAC.