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Analysis of Circular Reinforced Tunnels by Analytical Approach Ahmad Fahimifar1 ; Masoud Ranjbarnia 2 This paper addresses the problem of quantifying the mechanical contribution of rockbolts installed systematically around tunnels (regularly spaced around the tunnel) excavated in rock masses. Assuming that the mechanical contribution of grouted rockbolts is that of increasing internal pressure within a broken rock mass, a new procedure for computation of ground response curves for a circular tunnel excavated in strain softening material and then reinforced with systematically active grouted rockbolts is presented. In this work, the equation of the ground response curve for a tunnel which has been reinforced with passive grouted rockbolts is also derived. The proposed model allows one to take into account the effect of the distance of the bolted section to the tunnel face, the effect of increasing rockbolts spacing, the influence of increasing pretension load in calculating of the ground response curve, and the effect of increasing the cross-section area of rockbolts. The results show that decreasing rockbolts spacing increases the support system stiffness rather than preloading of them. منبع دانلود JSEG161329597000.pdf

Analytical solution of hurricane wave forces acting on submerged bridge decks Anxin Guo, , Qinghe Fang, Hui Li Abstract Hurricane waves are catastrophic disasters that cause damage to coastal bridges with insufficient clearance. This study presents an analytical method to estimate the wave forces acting on a submerged bridge superstructure during a hurricane based on the potential flow approach. The boundary value problem of the submerged bridge deck under wave action is analyzed first, and the mathematical formula for the analytical solution is derived using the eigenfunction matching method. To validate the effectiveness of the analytical model, results are compared to test data from two hydrodynamic experiments on the wave action of bridge decks. Finally, the AASHTO model is discussed, and a simple method for estimating the maximum horizontal and vertical wave forces is proposed. The analysis results indicate that the proposed analytical model can be used effectively for prediction of the maximum wave forces acting on a submerged bridge superstructure during hurricane waves. 10.1016_J.OCEANENG.2015.08.018-Analytical-solution-of-hurricane-wave-forces-acting-on-submerged-bridge-decks.rar