Hole layout calculation method of reinforced concrete beam demolition with soundless chemical demolition agents: Experimental investigation

Abstract

Nowadays, urban renewal is accompanied by the demolition of a large number of obsolete buildings. The pollutions caused by blasting demolition have a serious adverse impact on the environment. Soundless chemical demolition agents (SCDAs) are put forward as a green and environment–friendly demolition method and have the potential to solve the pollution problems in the blasting demolition of concrete buildings. To this end, this paper aims to investigate the key problems in reinforced concrete beam demolition with SCDAs. The tests on 18 reinforced concrete beam specimens were carried out. The fracture phenomenon and failure mechanism were analysed. The expansive rate of SCDAs was proposed as the crushing effect index to investigate the impacts of hole diameter, hole spacing, concrete strength, stirrup spacing, and stirrup diameter. Besides, the influence mechanism of the stirrups was explored in depth, in which SCDAs in the hole were considered to be constrained by the surrounding concrete, and the stirrups were considered as the enhancement to the constraint of concrete. Eventually, a new hole layout calculation method was proposed, which accorded well with the experimental results.