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. ...

IVind ttiimel tests on silty textured loessial soils throtigbout the Cohimhia Plateau of eastern Wa.shiitg{on slate and northern central Oregon were used ro define soil erndibiltiy for wind erosion predictions. Aggregate and primary particle size distributions were determined hy common techniques and correlated wiih the wind tunnel erosion values. Dry aerodynamic particle sizing by a laser meth...

The construction of tunnels in densely populated urban areas poses a significant challenge terms anticipating the settlement that may result from tunnel excavation. This paper presents new and more realistic modeling method for excavation using Tunnel Boring Machine (TBM). is compared with other reference methods validated model subsurface excavated by TBM slurry shield. A parametric study cond...

In this study, based on the actual project in Dalian, dynamic interaction of double tunnel sand bridge pile system (SSSI) under earthquake action is studied by shaking table test, and response laws structure site are obtained, which compared with ABAQUS numerical simulation. The Kelvin constitutive model subprogram introduced into model, equivalent linear method used to deal nonlinear problems ...

Radiative heterogeneity in greenhouses significantly influences crop activity, particularly transpiration and photosynthesis. This is especially true for plastic tunnels, which are the most commonly used greenhouse type in the Mediterranean basin. A computer model was generated for this study based on sun movement, greenhouse geometry, transmittance of the cover and weather conditions. Experime...

Tunnel excavation in urban areas causes ground movements that could damage existing nearby piled structures. Geotechnical centrifuge modelling has been widely used as a tool to study problems related tunnelling activities and its interaction with infrastructure systems. Recent hybrid tests using the Coupled Centrifuge-Numerical Modelling (CCNM) approach have provided high-quality experimental d...

BACKGROUND Non-repellent insecticides, including fipronil and indoxacarb, are becoming increasingly important for soil treatments to manage the eastern subterranean termite, Reticulitermes flavipes (Kollar). The effects of these insecticides on termite walking and tunneling behavior could significantly reduce their efficacy against colonies. RESULTS Groups of R. flavipes were exposed to sever...

The response of a massif to stresses generated by tunnel excavation depends essentially on the geological conditions, geometry and its underground position. major problem related construction these structures is ensure stability whole tunnel-ground, controlling various deformation during construction. In this context, present paper examines effect conditions behavior tunnels surrounding soil. s...