Effect Of Soil-squeezing By PHC Pile-driving Evaluation Of Ligang Power Plant

With the continually and stable development of civil economy, kind of engineering such as skyscrapers and electronic power engineering, are being built with unmatchable speed in the country. The effect on environment during pile driving is received more and more emphases by civil engineer. In this paper the changing law of ground heaves, lateral displacement of soil around pile, stress of pushing against soil and the influences on the ambient piles are studied. The effect of soil-squeezing and pore pressure is analyzed using the cavity expansion theory. Conclusions are obtained basing on LiGang power plant project. The author has described environment monitor technology relating to the effect of pile driving.Firstly, pore pressure monitors The famous effective stress principle of saturated soil is an elemental principle to describe the effect of pore-pressure that is a main stress characteristic of porous medium of multiple phases and they have different effects on dynamic characteristics of saturated soil because of their different producing reasons in mechanism. Under the same draining condition, the up produced due to the steady pore-water seepage, which is in equilibrium system of forces and take no effect on the deformation of soil, can affect the dynamic deformation property of saturated sand when the dynamic residual pore pressure occurs owing to the destruction of its microstructure. this may result in the local or whole unsteady water permeation from the un-balanceable distribution of pore pressure, and consequently induce the obvious degradation of dynamic properties in comparison. Pore pressure in soil during pile driving is researched. On the basis of analysis of a large amount of observation datum, the regularity ofaccumulation, dissipation and influence of pore pressure are found.Secondly, soil-squeezing monitors. In this paper the problem of pile driving is qualitatively analyzed, some conclusions about soil displacement are obtained. The effect of soil-squeezing due to vertical soil yield is described, the soil strength parameter relating to pile driving is studied. The author has put forward some effective measures to prevent or reduce the damages to the engineering environment in the vicinity.Thirdly, the ground vibration monitors. This paper introduces the research result of the application of engineering seismograph in detecting the mechanism of foundation vibration and seismic intensity caused by the seismic energy sources from artificial pile drive harmer and explosion. The result plays an important role in the prediction and assessment of seismic hazard, anti-seismic design and directing safe engineering construction etc.At last, based on the results of in-situ test of pile and pile driving measurement in a power plant project. The PHC pile drivability in hard layers is discussed.