Evaluation of Extension of Building Lifetime toward Reduction of Demolished Concrete Using Multi-agent System

摘要

There have been many technical and social proposals to reduce the emission of wastes or CO_2, such as development of skeleton-infill design methods, nondestructive inspection of concrete structures and section mending etc. Most of these proposals eventually aim to enlarge the lifetime of buildings as a means of reducing the emission of wastes from construction industries. However, almost none of the researchers of these methods have mentioned the qualitative effect of the reduction of waste emission. In order to evaluate both in technical and social aspects of resource-flow, we have developed a resource flow simulation system using the concept of Multi-Agent-System. The system especially focuses on the decision-making dynamics between each company and government within the city-scale so that social constraint of resource flow can be simulated properly. The system also uses the concept of graph theory to model the supply-chain and time. Thus quantitative balance of resource over the timeline could be investigated. In this paper, comparative case studies are made to evaluate the effect of enlargement of building lifetime to reduce the demolished concrete using the above-mentioned system. The studies especially focus on the quantitative balance between the building demand and waste emission. Geographical distribution of building demand and difference between decision-makings of each company are also taken into consideration. The results have shown that even in the idealistic situation when the deteriorated buildings built in 1970s would sizably enlarge its lifetime, the demolished concrete that are land-filled would overwhelmingly increase in its amount.