To address the seismic face stability challenges encountered in urban and subsea tunnel construction,an efficient probabilistic analysis framework for shield tunnel faces under seismic conditions is proposed.Based on ...To address the seismic face stability challenges encountered in urban and subsea tunnel construction,an efficient probabilistic analysis framework for shield tunnel faces under seismic conditions is proposed.Based on the upper-bound theory of limit analysis,an improved three-dimensional discrete deterministic mechanism,accounting for the heterogeneous nature of soil media,is formulated to evaluate seismic face stability.The metamodel of failure probabilistic assessments for seismic tunnel faces is constructed by integrating the sparse polynomial chaos expansion method(SPCE)with the modified pseudo-dynamic approach(MPD).The improved deterministic model is validated by comparing with published literature and numerical simulations results,and the SPCE-MPD metamodel is examined with the traditional MCS method.Based on the SPCE-MPD metamodels,the seismic effects on face failure probability and reliability index are presented and the global sensitivity analysis(GSA)is involved to reflect the influence order of seismic action parameters.Finally,the proposed approach is tested to be effective by a engineering case of the Chengdu outer ring tunnel.The results show that higher uncertainty of seismic response on face stability should be noticed in areas with intense earthquakes and variation of seismic wave velocity has the most profound influence on tunnel face stability.展开更多
在建立六自由度焊装机器人D-H坐标系及确定各手臂参数的基础上,研究其正逆运动学方程,设计其数值模拟算法,并在MATLAB环境下建立仿真模型,获得在定点控制模式下各个关节电机控制量,得到具有固定重力补偿的机器人控制模型;基于六自由度...在建立六自由度焊装机器人D-H坐标系及确定各手臂参数的基础上,研究其正逆运动学方程,设计其数值模拟算法,并在MATLAB环境下建立仿真模型,获得在定点控制模式下各个关节电机控制量,得到具有固定重力补偿的机器人控制模型;基于六自由度机器人动力学控制原理,在考虑电机特性及机器人手臂动力学特性的基础上,建立了具有传感器反馈控制的优化模型;在Tecnomatix环境下创建了四机器人焊接工位,利用其提供的Robotics功能模块,实现了机器人的路径及功能示教;利用DSP(Digital Single Processor,数字信号处理器)解算了机器人关节坐标的牛顿-欧拉逆运动学方程,并实时、快速处理传感器反馈信号,实现了对多个伺服系统的闭环控制。展开更多
基金Project([2018]3010)supported by the Guizhou Provincial Science and Technology Major Project,China。
文摘To address the seismic face stability challenges encountered in urban and subsea tunnel construction,an efficient probabilistic analysis framework for shield tunnel faces under seismic conditions is proposed.Based on the upper-bound theory of limit analysis,an improved three-dimensional discrete deterministic mechanism,accounting for the heterogeneous nature of soil media,is formulated to evaluate seismic face stability.The metamodel of failure probabilistic assessments for seismic tunnel faces is constructed by integrating the sparse polynomial chaos expansion method(SPCE)with the modified pseudo-dynamic approach(MPD).The improved deterministic model is validated by comparing with published literature and numerical simulations results,and the SPCE-MPD metamodel is examined with the traditional MCS method.Based on the SPCE-MPD metamodels,the seismic effects on face failure probability and reliability index are presented and the global sensitivity analysis(GSA)is involved to reflect the influence order of seismic action parameters.Finally,the proposed approach is tested to be effective by a engineering case of the Chengdu outer ring tunnel.The results show that higher uncertainty of seismic response on face stability should be noticed in areas with intense earthquakes and variation of seismic wave velocity has the most profound influence on tunnel face stability.
文摘在建立六自由度焊装机器人D-H坐标系及确定各手臂参数的基础上,研究其正逆运动学方程,设计其数值模拟算法,并在MATLAB环境下建立仿真模型,获得在定点控制模式下各个关节电机控制量,得到具有固定重力补偿的机器人控制模型;基于六自由度机器人动力学控制原理,在考虑电机特性及机器人手臂动力学特性的基础上,建立了具有传感器反馈控制的优化模型;在Tecnomatix环境下创建了四机器人焊接工位,利用其提供的Robotics功能模块,实现了机器人的路径及功能示教;利用DSP(Digital Single Processor,数字信号处理器)解算了机器人关节坐标的牛顿-欧拉逆运动学方程,并实时、快速处理传感器反馈信号,实现了对多个伺服系统的闭环控制。
