Study On The Volume Stability Of Coal Gangue Ceramsite Lightweight Aggregate Concrete

Coal gangue is one of the largest industrial solid wastes in our country, accounting for one quarter of the total industrial wastes, and is still in a large increase every year. Coal gangue piled perennially not only occupied a large amount of land, but also caused serious pollution and destruction to the environment. Producing lightweight aggregate concrete with coal gangue ceramsite, not only able to make use of large amount of coal gangue, thus enhance it’s reusing, but also greatly reduce the dosage of natural aggregate in civil engineering, and has great significance for the comprehensive utilization of coal gangue and the development of green building materials. Especially with the increasingly reinforced constraints of resources environment in the process of urbanization and urgent demand of the development of green energy-saving building, lightweight aggregate concrete which has the advantages of lightweight, high strength, heat insulation would has a very wide application foreground. However, for LWAC characterizing by low elastic modulus ceramsite and high cement content, the shrinkage distortion is often remarkable, and when it restrained can be a cause of cracking which go against the durability of concrete. Therefore, this article studies the effect of reduction measures on shrinkage and mechanical properties to improve the volume stability of coal gangue ceramsite lightweight aggregate concrete, which is conducive to its application m engineering.In this paper, with the consideration of substantially reduce shrinkage distortion, a good work performance LC30 lightweight aggregate concrete with local coal gangue ceramsite was developed. On this basis, the article studies the absorbency and release properties of coal gangue ceramsite, the physical properties of SRA, the influences of SRA and internal curing with LWA on the volume stability and strength of LWAC, and a combination of SRA and internal curing is proposed in order to make use of favorable condition and avoid unfavorable conditions of SRA and internal curing.The results show that the CGCLWAC which can meets engineering structure strength requirements is configured by local coal gangue ceramsite. Based on the results of influence of SRA and internal curing with LWA on the volume stability and strength of LWAC, it is found that SRA have an excellent performance on shrinkage mitigation, while it has defects on strength, but the influence of internal curing with LWA on long-term strength is quite the contrary. when SRA combined internal curing with LWA, the experiment results are indicated that this combination can significantly decrease shrinkage development and compensate the adverse effects of SRA on strength development by the hydration accelerating by the internal curing.