A kind of metro shock-absorbing vibration-isolation elastic hybrid lightweight track bed

Abstract

The invention discloses a metro shock absorption and vibration isolation elastic mixed light track bed. The metro shock absorption and vibration isolation elastic mixed light track bed comprises an elastic light concrete layer, wherein the elastic light concrete layer is arranged at the bottom of a metro track bed and used as a base track bed, and pouring material of the elastic light concrete layer comprises a mixture of concrete and expandable polystyrene (EPS) particles. According to the metro shock absorption and vibration isolation elastic mixed light track bed, the mixture of the concrete and the EPS particles is used, the EPS particles have the functions of : 1) absorbing vibration waves and vibration energy, which are generated during the running process of a metro train; 2) generating small transmission energy for an elastic light track bed base layer by being mixed with the concrete due to the fact that wave impedance differences of the EPS particles and the concrete are large. Accordingly, a small part of the vibration energy of the metro train can be transmitted to a metro tunnel lining or a metro duct piece, and furthermore vibration influences on ground and a foundation are weakened.

Description

technical field [0001] The invention relates to a shock-absorbing, vibration-isolating, and elastic hybrid lightweight track bed for subways, in particular to a shock-absorbing, vibration-isolating, elastic, and lightweight track bed for subways. Background technique [0002] With the acceleration of my country's subway construction and the continuous increase of operating mileage, ensuring the harmony and safety of subway operation is not only an important livelihood project, but also a strategic project for urban development of green economy. According to statistics, the subway traffic of several major cities in 2013: the average daily passenger flow of the Beijing subway reached 10 million passengers / day, the average daily passenger flow of the Shanghai subway was close to 7 million passengers / day, and the average daily passenger flow of the Guangzhou subway exceeded 5 million passengers / day. The average daily passenger flow of Nanjing Metro reaches 1.5 million passengers...

AI Technical Summary

Problems solved by technology

In addition, shallow-buried subways face complex working conditions. On the one hand, the shallow soil layers are mostly Quaternary strata, with many weak soil layers, and the variation of physical and mechanical properties of the soil layers is very complicated; the subway line is long, crossing different soil layers or Geological units, large rivers and lakes will also be encountered at the same time. The subway structure of the large rivers and lakes will inevitably bear high water pressure, and there will be pressurized groundwater. The environment is very complicated

Therefore, the shallow buried subway brings the following problems: ①The cumulative deformation of the surrounding soft soil (weak surrounding rock) is difficult to control, ②The impact of the vibration of the subway train increases the adverse effects of cumulative deformation and durable anti-seepage of the lining structure

[0008] 4. Adopt suitable ballast bed and track structure type, increase the elasticity of the track, and add a rubber backing plate with a small static stiffness coefficient, the vibration attenuation can reach 5-10dB, but the service life is short, the later vibration damping effect is poor, and it cannot be replaced

[0009] Although these shock-absorbing measures have achieved certain effects, the cumulative deformation of the foundation under the subway caused by long-term periodic vibration has continued to increase, which has threatened the safe operation of the subway and greatly increased the operation and maintenance costs.

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