Sharif Digital Repository

Ground vibration during pile driving is one the most important factors that limits usage of this kind of piles. It is of great importance to estimate the level of vibration prior to the beginning of pile driving to avoid structural damage or disturbance of building occupants. In this study, an axisymmetric finite element model that utilises an adaptive meshing algorithm has been introduced, using the commercial code ABAQUS, to simulate the full penetration of a pile from the ground surface to the desired depth by applying successive hammer impacts. The model has been verified by comparing the computed particles velocity with those measured in the field. The results indicate that the peak... 

Gas and oil reservoirs on Caspian Sea made Engineers to choose suitable riser for conveying oil and gas. Steel catenary riser is one of the best choices for deep and ultra-deep water. Although these kinds of risers show very good resistance on buckling but cyclic loads made them to fail by fatigue damage. Two sensitive points regarding to fatigue damage are Hang off point and touch down point. Fatigue damage on TDP is related to soil properties. Because of the cyclic movement of the riser a trench would shape on seabed. In this research, based on Finite element analysis, the effect of trench on fatigue life of SCR would be analyzed  

Train-induced vibrations can disturb the residential areas close to the rail as well as making ground-borne noises that can create problems for sensitive apparatus and devices. To reduce these problems, there need to be an evaluation of the amplitude of the ground-borne vibrations. The goal in this study is creating a suitable finite difference model in order to predict the intensity of train induced vibrations propagating inside or on the surface of the soil using FLAC (Fast Lagrangian Analysis of Continua) software as well as assessing the effectiveness of recycled shredded tires in reducing the surface vibrations by using these material as the filler for vibration isolation trenches. The... 

Ground vibration induced by human activity such as industrial activities, Blasting, in construction or deconstruction operation. Ground vibration reaches the troublesome limit for men. In the densely populated urban regions and buildings housing, ground vibration has to be strictly controlled. Many vibration reduction methods have been proposed.A metod of protecting structures from dynamic loads is using trench wich will be located between the dynamic sources and the protected structures. Inappropriate designing of trenches will reduce its effect. In this research the effect of trenches and their different properties, such as type of material, width, trench depth, soil bed type and distance...