Page - 855 - in Book of Full Papers - Symposium Hydro Engineering

the stress values depend on the ratio of E(Hardfill) to E(rock). However, we will consider the E(rock) values equal to 1 GPa for simplicity. Fig. 8 Modulus of deformation vs. compressive strength As indicated in Fig. 8 (middle), if a satisfactory fixed curve is not obtained for the relationship between Ec and f’c of Hardfill, each sample of the Hardfill material may generate a different curve, which in turn yields a different stress safety factor. The challenge is coming up with a way to find a minimum f’c for Hardfill that also satisfies the allowable safety factors. The following factors are presumed to affect the output results: - The relationship between f’c and Ec in lab tests - Estimating the modulus of the “Hardfill mass” (Discussed in the section 4) - The probabilistic parameters of the rock foundation (Discussed in the section 3) The formulae of the probabilistic functions are defined as follows: The probabilistic formulation for the relationship between f’c and Ec can be put this way: Were there enough tests available to relate E to f’c, we could stablish a probabilistic formula instead of a fitting curve with a low coefficient factor. Nevertheless, we are obliged to assume “a” as a random normal distribution (with µ=3.5 and σ=0.5) and “b” equal to 0.5 based on the vast experiment results in lean RCCs. 855