Experimental Study On The Influence Of Trench Isolation Effect Under Continuous Load

From the north to the south,rail transit allows us to make progress in the morning;from the city to the countryside,rail transit allows us to appreciate the natural scenery,and high-speed rail has become an indispensable tool in people’s lives.From a macro perspective,high-speed railways not only promote people’s transportation convenience,but also play a huge role in promoting the development of my country’s national economy.Therefore,the development of rail transit has been valued and reused in many countries,and it has become a must-choice transportation tool for people to travel.The propagation characteristics of Rayleigh waves excited by continuous loads are studied through field tests,and contour maps are drawn using the amplitude reduction ratio Ar value,coupled with the research method of one-dimensional continuity analysis of characteristic profiles,to analyze trench depth,trench width and vibration source The influence of the change of the distance on the vibration isolation effect,the following conclusions are drawn:(1)Under the excitation of continuous load,the Rayleigh wave presents a linear propagation law,with a wide excitation range,high intensity,and close to real life vibration conditions.(2)Under continuous load excitation,when the Rayleigh wave is injected,the Rayleigh wave presents a smooth linear shape in the area close to the vibration isolation groove,and the rear side is due to the Rayleigh wave penetrating into the vibration isolation groove.The resulting complex coherent effects such as emitted waves and transmitted waves cause disorder of linear characteristics.(3)The depth of the groove is an important factor affecting the vibration isolation effect of the groove.As the groove depth increases,the effective vibration isolation area becomes larger.When the groove depth is 50 cm,the effective vibration isolation area is 37.31 times that when the groove depth is 10 cm.Therefore,as the groove depth increases,the vibration isolation effect increases significantly.(4)The change of the groove width has no significant influence on the vibration isolation effect.The effective vibration isolation area when the groove width is 5cm is only 3.91 times that when the groove width is 25 cm.The amplitude reduction ratio Ar value drops to about 0.24 and enters a stable stage,with a slight increase.(5)The change of the vibration source distance has a significant impact on the vibration isolation effect.With the increase of the vibration source distance,the area of the effective vibration isolation area first increases and then decreases.When the vibration source distance is 35 cm,the effective vibration isolation area area is 9.6times that when the vibration source distance is 104.Therefore,as the vibration source distance decreases,the vibration isolation effect is enhanced.(6)The vibration isolation effect is also gradually enhanced with the increase of the vibration frequency.Secondly,this paper studies the influence of the relationship between the geometric parameters of the vibration isolation trench and the wavelength of the Rayleigh wave on the vibration isolation effect and the optimization design under continuous load through field tests,and draws the following conclusions:(1)The depth of the groove is the most important factor affecting the vibration isolation effect of the groove.D in the range of 0.5 to 0.6 can be used as the boundary range of the effective width.(2)Contrary to the change of the depth parameter D,the change of the groove width w has no significant influence on the vibration isolation effect of the groove.When the W value is 0.05,the vibration isolation effect is the best.At this time,when the vibration isolation groove is used as a vibration isolation barrier,the vibration isolation effect is the best,which can be used as the limit value of the effective groove depth.(3)The vibration source distance is also an important factor affecting the vibration isolation effect of the groove.With the increase of the vibration source distance parameter E,the amplitude reduction has a gradually increasing trend than the Ar value as a whole.When the E value is in the range of 0.32 to 0.6,the Ar value is small and will not change with the change of the E value.At this time,the vibration isolation groove is the best vibration isolation effect when used as a vibration isolation barrier,and can be used as an effective groove Depth limit range.