Brittle failure simulation of Pahang Selangor raw water transfer tunnel under rock overstressing/Heyam H. Shaalan, Mohd Ashraf Mohamad Ismail, Romziah Azit
Modelling a rock brittle failure around underground openings is used to simulate or contemplate the shape, depth and extent of the failure zone and achieved a suitable ground support system, consequently the underground construction safety increases and the construction cost decreases. This study analyses the critical section of the Pahang Selangor Raw Water Transfer Tunnel under high overburden using the 21) elasto-plastic finite elements stress analysis software. Site observations showed that the high overburden stresses created a failure zone on the tunnel sides, which damaged the steel fiber reinforced shotcrete lining. The observed failure depth is approximately 0.3 m. A numerical analysis is performed to predict the extent, shape and depth of the actual failure. Various approaches are adopted in the numerical modelling, which include the elastic analysis model, elastic-perfectly-plastic model and elastic-brittle-plastic model with (m = 0 and Sr — 0.11) and instantaneous cohesion-softening friction-hardening (CSFH) model. A parametric study on the CSFH model strength parameters is also implemented to describe the influence of the strength parameters on the extent, shape and depth of the failure, as well as investigate which parameters can simulate the actual failure depth. Results are compared with the observed failure to decide which approach can predict the actual failure. The (CSFH) model results predict the observed failure depth and shape correctly.
Brittle failure simulation of Pahang Selangor raw water transfer tunnel under rock overstressing/Heyam H. Shaalan, Mohd Ashraf Mohamad Ismail, Romziah Azit
Brittle failure simulation of Pahang Selangor raw water transfer tunnel under rock overstressing/Heyam H. Shaalan, Mohd Ashraf Mohamad Ismail, Romziah Azit