Based on convolution-type constitutive equations for linear viscoelastic materials with damage and the hypotheses of Timoshenko beams with large deflections, the nonlinear equations governing dynamical behavior of Tim...Based on convolution-type constitutive equations for linear viscoelastic materials with damage and the hypotheses of Timoshenko beams with large deflections, the nonlinear equations governing dynamical behavior of Timoshenko beams with damage on viscoelastic foundation were firstly derived. By using the Galerkin method in spatial domain, the nonlinear integro-partial differential (equations) were transformed into a set of integro-ordinary differential equations. The numerical methods in nonlinear dynamical systems, such as the phase-trajectory diagram, Poincare section and bifurcation figure, were used to solve the simplified systems of equations. It could be seen that simplified dynamical systems possess the plenty of nonlinear dynamical properties. The influence of load and material parameters on the dynamic behavior of nonlinear system were investigated in detail.展开更多
The primary objective of this study was to evaluate the existing conditions and the stability of a mining site in which the unique features of seismicity, mining activity, hydrological conditions, geological condition...The primary objective of this study was to evaluate the existing conditions and the stability of a mining site in which the unique features of seismicity, mining activity, hydrological conditions, geological conditions, environmental conditions, and future development plans were considered. In particular, the potential subsidence locations near the proposed construction site, the effects of mining boundary profile,and the influence scope of the mining activity on the neighboring areas were investigated using the finite element method. The study results indicate:(1) the overlying sandstone layer to the coal layer is the key to the stability of the mining roof;(2) the broken boundary has the most effect, followed by the arc boundary and linear boundary;(3) the safe distance from the mining boundary should be at least400 m if the proposed structure is to be built near an active mining site. Other relevant engineering recommendations are also proposed. The concluded results from this study may serve as a guide to other similar sites in the world.展开更多
According to the status of the northern rural architecture analysis, the prevalence of high energy consumption, low comfort features, it is essential to design energy-efficient buildings in rural areas. Article resear...According to the status of the northern rural architecture analysis, the prevalence of high energy consumption, low comfort features, it is essential to design energy-efficient buildings in rural areas. Article research and analyze the layout of rural buildings, a variety of energy-saving technologies and building design measures development and utilization of new energy sources and other issues that can make rural buildings to save energy and improve the environmental quality of living of farmers. It also put forward some reasonable suggestions for carrying out residential building energy efficiency in cold areas.展开更多
文摘Based on convolution-type constitutive equations for linear viscoelastic materials with damage and the hypotheses of Timoshenko beams with large deflections, the nonlinear equations governing dynamical behavior of Timoshenko beams with damage on viscoelastic foundation were firstly derived. By using the Galerkin method in spatial domain, the nonlinear integro-partial differential (equations) were transformed into a set of integro-ordinary differential equations. The numerical methods in nonlinear dynamical systems, such as the phase-trajectory diagram, Poincare section and bifurcation figure, were used to solve the simplified systems of equations. It could be seen that simplified dynamical systems possess the plenty of nonlinear dynamical properties. The influence of load and material parameters on the dynamic behavior of nonlinear system were investigated in detail.
基金Shaanxi Research Institute of Seismic Engineering, China for providing the necessary financial support for this study
文摘The primary objective of this study was to evaluate the existing conditions and the stability of a mining site in which the unique features of seismicity, mining activity, hydrological conditions, geological conditions, environmental conditions, and future development plans were considered. In particular, the potential subsidence locations near the proposed construction site, the effects of mining boundary profile,and the influence scope of the mining activity on the neighboring areas were investigated using the finite element method. The study results indicate:(1) the overlying sandstone layer to the coal layer is the key to the stability of the mining roof;(2) the broken boundary has the most effect, followed by the arc boundary and linear boundary;(3) the safe distance from the mining boundary should be at least400 m if the proposed structure is to be built near an active mining site. Other relevant engineering recommendations are also proposed. The concluded results from this study may serve as a guide to other similar sites in the world.
文摘According to the status of the northern rural architecture analysis, the prevalence of high energy consumption, low comfort features, it is essential to design energy-efficient buildings in rural areas. Article research and analyze the layout of rural buildings, a variety of energy-saving technologies and building design measures development and utilization of new energy sources and other issues that can make rural buildings to save energy and improve the environmental quality of living of farmers. It also put forward some reasonable suggestions for carrying out residential building energy efficiency in cold areas.
