Experimental Study On Bending Properties Of Reinforced Coal Gangue Concrete Beams

Coal gangue is a kind of associated waste of coal,which is separated in the process of coal washing,generally accounting for 10%-20% of the coal mining volume.China is a large energy country,and its coal mining volume is in the forefront of the world,and a large number of coal gangue has been accumulated.Most of the coal gangue have a low comprehensive utilization rate,which are generally stacked near the mining site,occupying a large amount of land resources.The application of coal gangue as coarse aggregate in components can not only effectively alleviate the shortage of natural crushed stone aggregate,but also make it produce value and turn waste into treasure.In this paper,five concrete beams with different gangue replacement ratio and one ordinary concrete beam were prepared by using gangue in Yushenfu mining area of Northern Shaanxi Province,which as coarse aggregate and replacing natural aggregate with 0%,40%,70% and 100% replacement ratio,respectively.This paper mainly analyzes the influence of gangue replacement ratio on the cracking load,ultimate flexural capacity,deflection and maximum crack width of the beam,and compares it with the test phenomenon of ordinary concrete beam.The specific research contents are as follows:(1)Considering the three factors of gangue replacement ratio,water cement ratio and admixture,the specimen was made to study the basic mechanical properties of gangue concrete.(2)This paper studies the difference of ultimate flexural bearing capacity of gangue concrete beams with different replacement ratio,and analyzes the difference of failure process between gangue concrete beams and ordinary concrete beam.The rationality of plane section assumption is verified by the results,and the applicability of bearing capacity formula is proposed.(3)The crack resistance performance of concrete beams with different coal gangue replacement ratio is studied by experiments,and compared with the cracking load calculation formula of ordinary concrete beam.(4)The deflection values of beams with different coal gangue replacement ratio are recorded in the test process,and the deformation difference of concrete beams with different replacement ratio is compared,the applicability of deflection calculation formula is analyzed,and correction suggestions are put forward.