| With the rapid development of urbanization,residential buildings,municipal roads and ancillary facilities have been constantly renovated,and billions of construction wastes have been constantly generated and accumulated.In many foreign countries,construction wastes are important renewable resource in many industries,however,China is facing the dilemma of garbage siege,which has a serious adverse impact on the environment.From the aspects of environmental protection and resources,the recycling and reuse of construction waste is an urgent issue that China must face directly.It is imperative to turn construction waste into treasure.First of all,this paper relies on the project of Tongzhou to Daxing of the ring highway in the Capital area.Based on the concept of environmental protection and recycling of resources,construction wastes are classified and screened by looking for a great deal of related literatures and spot investigation.According to the basic requirements of subgrade fillers,the systematic processing technology of usable construction wastes are put forward,the processed brick rubbish is subjected to a large number of laboratory tests such as particle analysis,boundary moisture content,compaction and so on.The various performance parameters are obtained to verify the feasibility of building roadbed with brick rubbish.Secondly,according to the characteristics of brick rubbish,the construction technology of subgrade filling is proposed.In the process of construction and the end stage,a large number of spot tests such as degree of compaction,differential settlement and deflection are applied to determine the reasonable construction parameters,For instance,mechanical combination,number of roller passes and depth of the loose laying,the settlement rate and regularity of subgrade filled with brick rubbish is obtained through the observation of subgrade settlement by embedding transverse pipe in subgrade.Finally,the research of brick rubbish is carried out under the conditions of different water content,ambient pressure and deviatoric stress through the indoor repeated loading triaxial test,and the factors affecting the permanent deformation of brick rubbish are obtained.The prediction model of permanent deformation of brick rubbish is determined by analyzing the influence factors.According to the design of subgrade and pavement structure of Capital Loop Expressway,the theoretical permanent deformation values of the subgrade under repeated loads are calculated by BISAR program.In this study,preliminary results have been achieved in the application of construction waste in subgrade filling,which can provide reference for the engineering of brick and muck subgrade filling in the later stage. |
