During the last decades, the railway traffic in densely populated areas has increased. At the same time, passenger trains have become faster and freight trains have become heavier. Consequently, trains are an increasing source of ground vibration, which may be a nuisance to people, buildings and sensitive equipment. In this research, a two-dimensional dynamic system, including underground train...

Abstract The aim of this study is to develop coupled matrix formulations characterize the dynamic interaction between vehicle, track, and tunnel. vehicle–track system established in light dynamics theory. physical characteristics mechanical behavior tunnel segments rings are modeled by finite element method, while soil layers vehicle–track–tunnel (VTT) as an assemblage 3-D mapping infinite elem...

In this research, under the disturbance of pre-dewatering, analytical solution vertical displacement adjacent tunnel is derived using two-stage analysis method. first stage, effective stress principle was used to calculate additional caused by dewatering. second Pasternak-Timoshenko beam model simulate interaction between and soil, taking shear deformation into account. By referring calculation...

High speed wind tunnels are widely used in the study of fluid flow behavior around various objects. The air flow in the starting step of supersonic wind tunnels is transient including strong shock waves caused by the interaction of the tunnel main stream and the boundary layer at walls. To arrive in running step, the tunnel must be designed so as these waves leave immediately the test section. ...

Abstract: In order to analyze the distribution rules and influence of stray current on subway rectangulartunneland subway Shield tunnel, threedimensional models were built separately. By changing the values of carry-current, ansys was used toanalyzeunder different geological conditions.Simulations show that the potential attenuation is nonlinear from the subway tunnel to the surrounding undergr...

This paper suggests a new set of analytical solutions for predicting leakage-induced seepage field and ground settlement in saturated clay. A unique feature of the solutions presented is considering the effect of the tunnel lining through the relative permeability between the tunnel and the soil. Through the superposition method, the proposed method can be easily extended to twin parallel tunne...

Seasonal frozen loess tunnel stability is controlled by many factors. To study the effects of water content and freeze-thaw cycles of loess tunnel stability, taking loess in Shanxi Yangqu No. 1 tunnel face as the research object, to do different moisture stability studies on loess tunnel after repeated freeze-thaw cycles. The results show that: (1) by the comprehensive structure potential and s...

Comprehensive control of odors, hydrogen sulfide (H2S), ammonia (NH3) and odorous volatile organic compound (VOC) emissions associated with animal production is a critical need. Current methods utilizing wind tunnels and flux chambers for measurements of gaseous emissions from area sources such as feedlots, lagoons, pastures and cropland are often criticized for potential bias. The bias is due ...