الفهرس | Only 14 pages are availabe for public view |
Abstract Vibra tory driving is a technique used for driving piles, tubes, and rodS into the ground by ~arting to the dri ving uni t a small longi tudinal vibra tory motion. Usually vibra tory pile drivers are used for the installation of piles in deep water mooring and ocean pIa tforms . Successful use of this method depending upon the co~uting operation regime of the vibratory equipment. The vibrations induced by the equipmen t serve to reduce the ground resistance allowing penetration under the action of a relatively small surcharge force in addi tion to the weigh t of the pile and the driver. Recently, there has been an increasing interest in the use of vibra tozy drivers for both pile driving and pile extraction. There has been also recent interest in utilizing vibratozy drivers for offshore applications. Because of the increased use of the vibratozy pile driving, there is a need for a numerical method to model the system and to evaluate the effects of the various parameters involved in the vibratozy pile driving process. Two s~le numerical approaches for the predic- tion of vibratozy pile driveability are presented in this study. In the First, the pile is represented by discrete elements, while the soil is modeled by series of springs and dashpots, the coefficients of which are derived using elasto-qynamic theory. A computer program using Newmark integration method was developed and constructed. This c~uter program was implemented to solve the equations of motion and to calculate the pile penetration, pile velocity, pile acceleration and pile forces in time domain. A parametric stuqy was concluded and the effect of different parameters concerning the pile, the soil and the driver characteristics were conducted |