Research On Source Characteristics Of Construction Demolition Waste

In recent years,with the acceleration of urbanization in China,the existing old buildings in major cities are faced with the problems of demolition and reconstruction,resulting in a sharp increase in the amount of demolition waste of housing and construction.If it is not properly disposed of,it will not only waste a lot of land resources,but also pollute the surrounding environment.The characteristics of the source of waste removal include the characteristics of occurrence type,quantitative characteristics and pollution characteristics.Scientific analysis of the characteristics is an important prerequisite for the accurate management and control of waste removal.At the project level,the amount of waste removed can be predicted,and on-site resources such as waste transport vehicles can be properly allocated to achieve precise control and dynamic management of waste removed.The analysis of the pollution characteristics of the dismantled garbage can provide the disposal basis for its subsequent harmlessness,resource recovery and reduction.Starting from the acquisition means of the technical indicators of the building to be demolished,the Uav tilt photosurveying technology is used as a tool to collect the field data of the demolished area,and based on the data,the internal 3D real scene modeling is carried out to obtain the 3D real scene model of the area to be demolished.Acute 3D View’s measurement tool was used to obtain the engineering specifications of the building to be demolished.Based on the classification of building types and structural components,the corresponding prediction model of the amount of demolition waste was proposed,and the construction engineering technical indicators required by the model were substituted into the calculation of the amount of demolition waste.The demolition project of the old Dihao cigarette factory in Xuchang city was taken as an example to verify the accuracy of the model.The results show that the error between the predicted amount and the actual amount is 8.3%,less than 10%,which has a high precision.Based on the analysis of the pollution characteristics of the demolition waste of housing construction,combined with pingdingshan,the demonstration city of the project,field sampling of the demolition waste in three different sites.In the analysis of samples at different sampling points and similar samples,the over-standard rates of Cr,Ni and Cu all reached the highest or the second highest,and the contents of Cr,Ni and Cu should be monitored in subsequent disposal.Based on the three different pollution risk assessment methods,it is indicated that there are many types of contaminated samples,showing point pollution,and the risk index of Zn and Cu pollution is high.Therefore,the pollution risk of Zn and Cu should be focused in the subsequent disposal.The results of the leaching toxicity test showed that the overall leaching pollution of the samples was mainly concentrated in Cr and Ni,and the monitoring of Cr and Ni should be strengthened and relevant anti-leaching treatment should be done if mixed stacking is needed in the subsequent disposal.Accurate prediction of the amount of demolished waste and analysis of pollution characteristics are important preconditions for the realization of its accurate control.Uav tilt photosurveying and 3D modeling technology can solve the problem of difficult acquisition of building indicators of old houses to be demolished in China.The prediction model predicts the amount of occurrence according to the building structure.For the structures that can be used twice,such as plates,beams and columns,they can be completely dismantled if necessary.The analysis of the pollution characteristics of the removed waste makes clear its environmental pollution attributes and potential human health risks,providing data support for the harmless disposal of the removed waste.