An experimental study on the mechanical properties of shotcrete.

In the last decade, the use of shotcrete in tunnel construction has rapidly increased and the shotcrete has become an important element of the modern tunnel support techniques. Nevertheless, the properties of shotcrete have not been sufficiently investigated.This paper presents the results of an experimental program to evaluate the properties of shotcrete relevant to the tunnel support systems. In the experiments the cubic specimens were prepared and tested to obtain the mechanical properties, especially the strength and Young's modulus in relation to curing time. From these results, the relationship among the uniaxial compressive strength, Young's modulus, curing time, failure strain and ultrasonic velocity are proposed and their relevancy are discussed.