The cable-strut structural system is statically and kinematically indeterminate. The initial pre-stress is a key factor for determining the shape and load carrying capacity. A new numerical algorithm is presented here...The cable-strut structural system is statically and kinematically indeterminate. The initial pre-stress is a key factor for determining the shape and load carrying capacity. A new numerical algorithm is presented herein for the initial pre-stress finding procedure of complete cable-strut assembly. This method is based on the linear adjustment theory and does not take into account the material behavior. By using this method,the initial pre-stress of the multi self-stress modes can be found easily and the cal-culation process is simplified and efficient also. Finally,the initial pre-stress and structural performances of a particular Levy cable dome are analyzed comprehensively. The algorithm has proven to be efficient and correct,and the numerical results are valuable for practical design of Levy cable dome.展开更多
The tensile cable-strut structure is a self-equilibrate pre-stressed system.The initial pre-stress cal- culation is the fundamental structural analysis.A new numerical procedure was developed.The force density method ...The tensile cable-strut structure is a self-equilibrate pre-stressed system.The initial pre-stress cal- culation is the fundamental structural analysis.A new numerical procedure was developed.The force density method is the cornerstone of analytical formula,and then introduced into linear adjustment theory;the least square least norm solution,the optimized initial pre-stress,is yielded.The initial pre-stress and structural performances of a particular single-layer saddle-shaped cable-net structure were analyzed with the developed method,which is proved to be efficient and correct.The modal analyses were performed with respect to various pre-stress levels.Finally,the structural performances were investigated comprehensively.展开更多
There are some basic problems in previous theoretical studies of baroclinic instability.The derived critical baroclinity was considerably lower than the time averaged mean meridional temperature gradient,especially in...There are some basic problems in previous theoretical studies of baroclinic instability.The derived critical baroclinity was considerably lower than the time averaged mean meridional temperature gradient,especially in the lower troposphere.Also,the linear mechanism of baroclinic disturbance development which is noted restricted by the critical baroclinity was not studied sufficiently.The realistic critical baroclinity and disturbance development are discussed in this study.It will be shown that the critical condition of instability and typical time and space scales of disturbances de- pend on three-dimensional structures of atmosphere and sphericity of the earth,other than the horizontal temperature gradient alone.The variant behaviour of atmospheric disturbances depends highly on their specific scales that may be described by the same theoretical model.Thus,there would be no substantial differences in the basic instability mecha- nism of many disturbances including the polar lows and explosive cyclones.展开更多
基金Project (No.863-705-210) supported by the Hi-Tech Research and Development Program (863) of China
文摘The cable-strut structural system is statically and kinematically indeterminate. The initial pre-stress is a key factor for determining the shape and load carrying capacity. A new numerical algorithm is presented herein for the initial pre-stress finding procedure of complete cable-strut assembly. This method is based on the linear adjustment theory and does not take into account the material behavior. By using this method,the initial pre-stress of the multi self-stress modes can be found easily and the cal-culation process is simplified and efficient also. Finally,the initial pre-stress and structural performances of a particular Levy cable dome are analyzed comprehensively. The algorithm has proven to be efficient and correct,and the numerical results are valuable for practical design of Levy cable dome.
文摘The tensile cable-strut structure is a self-equilibrate pre-stressed system.The initial pre-stress cal- culation is the fundamental structural analysis.A new numerical procedure was developed.The force density method is the cornerstone of analytical formula,and then introduced into linear adjustment theory;the least square least norm solution,the optimized initial pre-stress,is yielded.The initial pre-stress and structural performances of a particular single-layer saddle-shaped cable-net structure were analyzed with the developed method,which is proved to be efficient and correct.The modal analyses were performed with respect to various pre-stress levels.Finally,the structural performances were investigated comprehensively.
文摘There are some basic problems in previous theoretical studies of baroclinic instability.The derived critical baroclinity was considerably lower than the time averaged mean meridional temperature gradient,especially in the lower troposphere.Also,the linear mechanism of baroclinic disturbance development which is noted restricted by the critical baroclinity was not studied sufficiently.The realistic critical baroclinity and disturbance development are discussed in this study.It will be shown that the critical condition of instability and typical time and space scales of disturbances de- pend on three-dimensional structures of atmosphere and sphericity of the earth,other than the horizontal temperature gradient alone.The variant behaviour of atmospheric disturbances depends highly on their specific scales that may be described by the same theoretical model.Thus,there would be no substantial differences in the basic instability mecha- nism of many disturbances including the polar lows and explosive cyclones.
