Experimental study on dynamic elastic modulus loss of concrete broken by high voltage pulse discharge based on orthogonal design

Abstract

Abstract High pulse discharge breakage has a vast prospect as a fresh crushing mechanism for it has the capability to enhance the comminuting effect, however, the breaking mechanism is not yet well studied. In this orthogonal designed research, 27 indoor tests of high voltage pulse discharge (HVPD) for breaking concrete together with the determination of dynamic elastic modulus of concrete based on three variables, i.e. applied voltage, pulse number, and discharge electrode gap, were carried out at three levels. The effects of these factors were studied by using significance and range analysis. The results showed that among these factors, the pulse number has the greatest impact on the dynamic elastic modulus loss (DEML) of concrete, while the applied voltage has the least influence. By changing the value of pulse number and applied voltage, the DEML can be increased to 12.9% and 26.7%, respectively. The impact of the factors’ combination was experimentally proven, and the resulting DEML of concrete broken by HVPD was obtained as 219.73 ± 9.58 MPa, which was 25.19% higher than the maximum of the DEML of concrete broken by HVPD in the orthogonal experiment under various individual factors. These findings provide technical references for improving the crushing efficiency of concrete materials and the engineering application of HVPD crushing technology.

Keywords

• High-voltage pulse discharge breaking
• Dynamic elastic modulus loss
• Orthogonal test
• Concrete building materials