A Pre-Demolition Planning Framework to Balance Recyclability and Productivity

Pre-demolition planning involves a tradeoff between recyclability and productivity due to the factors affecting different stakeholders. Demolition contractors hope to maximize their profits by selling salvaged materials to recycling markets and avoid the disposal fees by diverting the waste from landfill sites. This may result in an extended duration of the demolition phase of the project due to the use of labor-intensive demolition methods that yield more salvageable materials. Owners and general contractors, on the other hand, try to avoid such extensions in their demolition plans as they can result in project delays and additional costs to the construction project that follows the demolition phase. Although these two opposing ideas (i.e., recyclability and productivity) serve as driving factors for pre-demolition planning, researchers and practitioners have rarely considered the tradeoffs in pre-demolition planning. This paper develops a framework to find the optimal balance between recyclability and productivity in pre-demolition planning, which determines combinations of different demolition methods (i.e., saw cutting and standard, mini, and high-reach excavators) to demolish different sections (or buildings) in a project. Linear programming is employed to find the demolition plan that maximizes the profit from salvaged materials within time constraints. Specifically, the developed model considers different costs associated with the demolition project, including clean fill disposal, landfilling, and direct demolition costs, along with the project’s scheduled time constraints. For demonstration, we implement the proposed framework to guide the development of a demolition plan for a project in the Midwestern United States.