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Construction and demolition waste (C&D waste) is a worldwide issue that concerns the sustainable development of the construction industry. In this paper, detailed formulas are listed for calculating the costs of four typical kinds of disposal routes of C&D waste. They are illegal dumping, controlled dumping (landfill), centralized recycling, and on-site recycling. Through the specific formulas, the costs of the new construction project in Guangzhou are also estimated. Then, a cost compensation model of construction waste disposal is constructed, which serves to calculate the amount of compensation that the government shall make to the contractor's disposal cost. The results of this study include the following: (1) steps taken to ensure the appropriate measures for C&D waste disposal sites and recycling centers; (2) the on-site recycling will become the future trend of C&D waste disposal due to its lowest cost; (3) the brick cement mortar and scattered concrete take a relatively larger proportion in the total C&D waste generated during the new construction project, and their disposal costs are higher; (4) we find that the cost of illegal dumping is the lowest among four varieties of waste treatment options if only the direct cost of waste treatment is taken account. However, the cost of on-site recycling becomes the lowest if the total cost is considered; (5) according to the case study, the full estimated cost of construction waste disposal is 9074.56 CNY and the total cost compensation is 15,084.21 CNY. The amount of compensation is greater than the disposal cost and contractors make a profit, thus stimulating them to recycle and reuse construction waste. Based on the empirical findings, we make several policy proposals. The research puts forward some operational advice as a reference for decision-makers of C&D waste management.

This paper presents a time- and cost-efficient method for the management of construction and demolition (C&D) debris at construction sites, demolition jobsites, and illegal C&D waste dumping sites. The developed method integrates various drone, deep learning, and geographic information system (GIS) technologies, including C&D debris drone scanning, 3D reconstruction with structure from motion (SfM), image segmentation with fully convolutional network (FCN), and C&D debris information management with georeferenced 2D and 3D as-built. Experiments and parameter analysis led us to conclude that (1) drone photogrammetry using top- and side-view images is effective in the 3D reconstruction of C&D debris (stockpiles); (2) FCNs are effective in C&D debris extraction with point cloud-generated RGB orthoimages with a high intersection over union (IoU) value of 0.9 for concrete debris; and (3) using FCN-generated pixelwise label images, point cloud-converted elevation data for projected area, and volume measurements of C&D debris is both robust and accurate. The developed automatic method provides quantitative and geographic information to support city governments in intelligent information management of C&D debris.