Development of a Powder-type Thin Spray-on Liner and Its Performance Evaluation at Different Curing Ages

Abstract

Thin Spray-on Liner (TSL) has been considered as a new rock support to replace shotcrete as well as wire mesh. However, the development of its original production technology is highly in demand since it is not open to the public. Therefore, two kinds of powder-type TSL prototypes were developed as the first development stage. Then, their mechanical properties were experimentally compared with those of a two-component foreign TSL material including both of liquid and powder components. From a series of experiments, the first TSL prototype mixing condition satisfied every TSL performance requirements specified by EFNRAC (2008), and showed much higher tensile and bond strengths than those of the two-component foreign TSL, even though the other TSL prototype cannot be used as a support member since its elongation at break is much lower than its corresponding EFNARC (2008) performance criterion. In addition, a further study to increase the ductility of the first TSL prototype might be necessary to guarantee its higher applicability to field conditions.