Preparation and mechanics property of coal chemical solid waste concrete
In order to solve the problems of large water absorption,poor fluidity and low strength caused by the large pores of coal chemical solid waste instead of sand and gravel in the preparation of concrete,solutions were proposed from two aspects:surface sealing coating treatment of solid waste coarse slag and morphology control of cement hydration products.Firstly,an adhesive curing agent(ACA)containing triazine ring,amino group and aldehyde group was prepared for surface treatment of solid waste coarse slag,which was mixed with cement to form a filling and plugging coating on the surface of solid waste coarse slag,so as to solve the problem of large water absorption and poor fluidity when preparing concrete from solid waste coarse slag of coal chemical industry.Secondly,graphene oxide(GO)was prepared and mixed with polycarboxylate superplasticizer(PC)to form an intercalated composite(PC-GO).By adding PC-GO,the uniform dispersion of ultra-low content GO in cement matrix and the regulation of the morphology and structure of cement hydration products were realized.High content of coal chemical solid waste concrete was prepared under the synergistic effect of surface plugging coating and structural regulation of cement hydration products.The structure of ACA and the mechanism of forming plugging coating were characterized.The adsorption dispersion mechanism of ultra-low content GO and the crystal nucleus effect and template effect of regulating the morphology of cement hydration products were proposed.The results show that the compressive strength of concrete containing 60%and 80%(mass fraction)coal chemical solid waste is greater than 40 MPa and 30 MPa respectively,and the flexural strength is greater than 6 MPa and 4.5 MPa respectively.At the same time,the high content of coal chemical solid waste concrete has good dry shrinkage resistance.The research results have positive significance for the preparation of high content coal chemical solid waste concrete and the large-scale resource utilization of coal chemical solid waste.
NETL
NSTL
万方数据
