Experimental Studies And Numerical Analyses Of The Strength Characteristics Of Construction Miscellaneous Fills

Construction miscellaneous fills composed of waste residue, waste concrete, waste brick and other wastes is a kind of complex structural, multicomponent and multiphase soil. It is different from the traditional soil. So far the studies of construction miscellaneous fills mainly concentrated on the recycling of construction waste and its application in municipal road engineering. The studies of strength characteristics of miscellaneous fill were most focused on municipal solid waste. Few researches have been conducted on the strength characteristics of construction miscellaneous fills. In this paper, indoor tests and numerical simulations were conducted to study the strength characteristics of construction miscellaneous fil s.The strength parameters of construction miscellaneous fills are influenced by many factors, among which the constitution of construction miscellaneous fills plays a decisive role in the strength parameters. Therefore, in this paper the study of strength parameters of construction miscellaneous fills mainly concentrated on the influence law of the strength parameters affected by different proportion of components and this paper includes the experimental studies and numerical analyses.In the experimental studies, through large-scale direct shear tests on silt, gravel soil, sand, clay and self- made construction miscellaneous fills, the corresponding strength parameters were obtained and the preliminary conclusions could be drawn by comparison. Different components of construction miscellaneous fills have an effect on the strength parameters. Compared with the strength parameters of the construction miscellaneous fills in which fine grained soil is the main component and those of the fine grained soil, its angle of internal friction increases and the cohesion decreases. The impact of cohesion is greater than that of angle of internal friction. And the result is the opposite when the main component is coarse grained soil. The impact of cohesion is smaller than that of angle of internal friction. While the component ratio of each group's proportion of construction waste miscellaneous is close to one to one, the strength parameters are between each component and are close to those of the soil whose grain size is medium. About the angle of internal friction, the fine grained soil has a lager influence than that of coarse grained soil. About the cohesion, the coarse grained soil has a larger influence than that of the fine grained soil.In the numerical analyses, the numerical simulations of direct shear tests on all types of soil were performed on the large general-purpose finite element software ABAQUS and the strength parameters were obtained. The results show that the strength parameters obtained by the numerical simulations are consistent with those got by the indoor tests, which proves that the large-scale direct shear tests and the finite element simulation of direct shear tests used in this paper can be considered as two effective means measuring the strength parameters of construction miscellaneous fills. And according to comparative analyses of the strength parameters obtained by the numerical simulations, the law which is consistent with the indoor tests was put forward.This paper investigated the influence law of the strength parameters of construction miscellaneous fills affected by different components. And the law can be used as the reference while estimating the strength parameters of construction miscellaneous fil s in engineering.