A study on the optimal use of soundless cracking demolition agents in fragmentations of concrete based on the extended finite element method

Abstract

Soundless cracking technique has been widely applied in the demolition of rock and concrete structures because of its cleaner advantages compared with conventional explosive methods. However, the correlations between fracturing processes and characteristics of soundless cracking demolition agents (SCDAs) and the optimal use of SCDA in improving the efficiency of demolition are still poorly documented. In this concern, this study develops a reliable numerical model verified by experimental data to investigate the optimal use of SCDA in fragmentations of concrete based on the extended finite element method. The simulated results reveal that the minimum hole diameter is 26 mm required to break the concrete cube of 150 mm, and the crack process can be divided into three phases of initiation, propagation, and coalescence according to the energy release rate. Moreover, the proposed method is employed in simulating the crack process of meter-scale concrete blocks with two predrilled holes, and the optimal hole spacing of 350 mm is then determined. This study provides some insights for improving the efficiency of SCDA in the field applications.

Directional fracturing of rock by soundless chemical demolition agents

“…Many scientists use the elasticity theory for the analysis of stress fields that are formed by SCDA. Also, the elastic approach is often used in the calculation of fracture parameters [ [54] , [55] , [56] ]. At the first step of the current study elastic simulation was also used.…”

Green demolition technology of reinforced concrete slab: Application of soundless chemical demolition agents and its evaluation system

“…The t was independently used to represent the progress of the expansive pressure development and the demolition process. Besides, the concrete around the hole was regarded as the constraint on SCDAs, which was related to the D , S H , and f cu 40–44 . The concrete constraint factor ( λ ) was provided to quantify the constraint of the concrete, as shown in Equation ().…”

“…Besides, the concrete around the hole was regarded as the constraint on SCDAs, which was related to the D, S H , and f cu . [40][41][42][43][44] The concrete constraint factor (λ) was provided to quantify the constraint of the concrete, as shown in Equation ( 8). The basis for determining its form was the quantitative analysis of the D, S H , and f cu .…”