Test On The Barrier Of Rayleigh Wave On Sand Surface By Concrete Pile

The impact of vibration involves building safety and the use of precision instruments.Generally,blocking barriers are set in the propagation medium of vibration waves to reduce its impact on the above aspects.The vibration isolation of row piles is less affected by soil quality than that of empty trenches.In this paper,tests are conducted on natural sandy soil foundations,and the changes in relative acceleration values on a two-dimensional plane are used to analyze the changes in soil vibration around the piles and the range of soil behind the piles that can be suppressed by the piles.The conclusions drawn under the experimental conditions of this article are as follows:1.For the soil vibration analysis test of row piles,this article systematically analyzes the vibration changes in front of,between piles,and behind piles,and the conclusions are as follows:(1)There is an increase in the amplitude of the soil surface in front of the piles,between the piles and on both sides of the piles.(2)The increase in the ratio of pile length to wavelength will increase the surface vibration of the soil in front of and between the piles,and weaken the vibration of the soil behind the piles.When the ratio is in the range of less than0.691,the soil vibration in front of and between the piles strengthens rapidly,and the soil vibration behind the pile is weakened;when the ratio is in the range of0.691 to 0.781,the soil vibration in front of and between the piles strengthens.Weakened,the soil vibration changes little behind the pile.(3)When the distance between piles and the ratio of Rayleigh wave wavelength increases,the soil vibration in front of,between piles and behind piles is weakened.In the range of 0.359～0.421,the three vibration areas tend to be the same.(4)The change of pile diameter has little effect on the vibration changes of the soil in front of the piles and between the piles,and will strengthen the vibration suppression effect of the piles on the soil.(5)When the ratio of the vibration source distance to the wavelength increases within the scope of this article,the soil vibration in front of and between the piles will increase,and the soil vibration suppression effect behind the piles will increase.2.In terms of the impact range of row pile vibration isolation,the line segment connecting the center of the exciter and the pile center in the contour map is used as the basis,and the length of the line segment with a relative acceleration value less than 0.6 is used as the vibration isolation radius to isolate the row piles.The scope of influence is studied,and the main conclusions are as follows:(1)When the ratio of pile length to wavelength reaches 0.820,the vibration isolation radius is increased to about 0.680 m.Therefore,when the pile length parameter is within this range,the pile length parameter can be increased to increase the impact of the row of piles on the soil behind the barrier.Length of suppression zone.(2)When the pile spacing parameter is between 0.300 and 0.400,there is no suppression area of the piles on the soil,and the suppression effect of the piles on the soil vibration basically disappears after the center of the piles.The range of influence of the row of piles can be increased by selecting a smaller pile spacing parameter.(3)When the vibration source distance parameter is in the range of0.165～0.305,there is no vibration isolation radius behind the pile,but when the ratio increases to about 0.808,the length of the vibration isolation radius increases to 0.512 m,and the growth rate is faster Therefore,a larger vibration source distance parameter can be selected in actual engineering vibration isolation.(4)The contribution of the pile diameter parameter to the vibration isolation radius is relatively small,and the restraint effect of the row of piles on the soil is most reflected in the length of 0.170 m behind the pile.