The Applicability Of The Construction Waste Recycled Materials As Subgrade Filling

Our country has a large population,and as the level of urbanization has accelerated,the construction industry has been developing rapidly,but the resulting construction waste is also increasing.Resource shortage and environmental pollution have become the bottleneck of sustainable development.The research of construction waste recycling utilization is not only beneficial to saving material,reduction,in turn,produce considerable social and economic benefits,but also for environmental protection and the optimization of the utilization of resources play an important role in promoting.How to recycle construction waste and reuse it effectively becomes a new issue in the develoment of urbanization.An important aspect of construction waste recycling utilization is used as roadbed filling.Road and railway construction in our country is at the peak,the construction waste recycled materials as a filler application and roadbed engineering,not only greatly reduce the exploitation of natural sand and gravel,and will be full of construction waste recycled utilization.In this paper,through series of researches,firstly measured the ratio of the construction waste classification,then did physical and mechanical experiment,lab large-scale direct shear test,the scene in situ test,finite element numerical calculation,and the settlement and then select the typical sections for field test.Through physical and mechanical characteristics of different proportion,we propose the applicability of the construction waste as roadbed filling.Through numerical calculation,we obtain the construction waste in the process of roadbed filling particles state of deformation and destruction.Through the field test,we put forward the construction method and reference standards of construction waste as roadbed filling.We do all this to make it better used in engineering practice,to promote the application of construction waste recycled material in roadbed treatment,to save resources,to reduce the cost and to provide technical support.According to the source of the construction waste classification,physical composition,classification,inert material classification and renewable utilization of classification,we classify construction waste according to different sources,composition and the available performance of different components.For the roadbed engineering,that construction waste can be recycled in the regeneration and utilization of the main components are brick bat,broken concrete blocks,broken brick,sandstone,waste mortar,cement products,the foundation pit and soil and so on.The research area is mainly composed of the construction waste coarse particles emitted brick bat,crumbled concrete blocks,stones,45% bricks,concrete blocks(40%),stones(15%).The stability analysis of roadbed was completed by using geo-studio and MIDAS/GTS according to the data obtained from laboratory test results and field tests.Limit equilibrium method and strength subtraction to calculate the stability coefficient is relatively close,the largest deviation was 6%,the sliding surface is relatively close to that of limit equilibrium method and strength subtraction are construction waste as a renewable materials as the calculation method of stability of subgrade filling.Can be seen from the diagram,the limit equilibrium method of sliding surface is an arc,and the strength subtraction is concluded that the sliding zone,the sliding zone is a part of the slope when strain leading,rather than its sliding surface;When the height of the roadbed is greater than or equal to 6.0 m,the roadbed is not safe.And when the roadbed filling height of 4.0 m,4.5 m or so,the stability coefficient is the largest,it shows that interlocking between recycled materials packing,strongest,occlusion,and led to the stability of roadbed is best;In the calculation of two-dimensional static load,the maximum subsidence deformation is the general clay filler,and the minimum deformation is gravel/fine grained soil filler.In three-dimensional dynamic load calculation,causes deformation of the maximum settlement is generally clay filler,the minimum deformation is gravel packing/fine grained soil,further confirmed that the construction waste recycled materials is a kind of excellent subgrade filling.