摘要
为了研究水中悬浮隧道在近场非接触爆炸荷载作用下的动力响应规律,将悬浮隧道简化为等截面等刚度的Bernoulli-Euler弹性支撑梁,建立悬浮隧道在爆炸冲击作用下的动力学模型,使用Galerkin法求解振动微分方程,结合一个悬浮隧道待建工程对其进行参数分析,讨论炸药量、爆心距、锚索竖向刚度对位移、速度、加速度的影响规律,并利用其结果对隧道和人体进行损伤分析.结果表明:爆心距对悬浮隧道运动学参数的影响显著,就位移而言随爆心距的增加隧道最大位移近似呈反比例下降趋势,与10 m爆心距相比,20 m和30 m工况下位移分别下降了50.7%,66.6%;炸药量对悬浮隧道运动学参数的影响显著,就位移而言随炸药量的增加隧道最大位移近似呈低阶幂函数上升趋势,与20 kg炸药量相比,40 kg和60 kg的峰值位移分别增加了29.8%,51.3%;锚索竖向刚度对悬浮隧道运动学参数的影响显著,就位移而言随锚索刚度的增加隧道的最大位移近似呈阶梯状下降趋势,与5×10^5 N/m的锚索刚度相比,5×10^6 N/m和5×10^7N/m工况下的隧道最大位移分别下降了53.0%,86.2%,但锚索刚度存在一个高效作用区间,当刚度在区间内,能显著地改变隧道管体的位移,当处在区间外(或大或小)时,对位移的影响不明显.
To investigate the dynamic responses of submerged floating tunnels(SFTs)subjected to near-field non-contact explosions,the SFT was simplified as a constant-section-and-stiffness Bernoulli-Euler elastic-support beam to establish the SFT dynamic model under underwater shock load.The differential equation for the vibration was resolved with the Galerkin method.The displacement,velocity and acceleration were analyzed for the SFT,the influences of the explosive quantity,the blasting distance and the vertical stiffness of anchor cables were discussed,and the results were also used to analyze the damage of tunnels and human bodies.The results show that,the impact of the blasting distance on the kinematic parameters of the SFT is significant.Moreover,the maximum displacement of the tunnel decreases in inverse proportion to the blasting distance.Compared with those of the blasting distance of 10 m,the displacements of the tunnel body of 20 m and 30 m decrease by 50.7%and 66.6%,respectively.The impact of the explosive quantity on the kinematic parameters of the SFT is significant.Also,the maximum displacement of the tunnel decreases approximately in a low-order power function with the explosive quantity.Compared with those of the explosive of 20 kg,the displacements of the tunnel body of 40 kg and 60 kg increase by 29.8%and 51.3%,respectively.The impact of the vertical stiffness of anchor cables on the kinematic parameters of the SFT is significant.Besides,the maximum displacement of the tunnel decreases approximately in a step-like form with the vertical stiffness of anchor cables.Compared with those of the vertical anchor stiffness of 5×10^5 N/m,the maximum displacement of the tunnel body of 5×10^6 N/m and 5×10^7 N/m decrease by 53.0%and 86.2%,respectively.However,there is an efficiently acting interval for the anchor cable stiffness.The stiffness has significant influence on the displacement of the tunnel body within the interval,but has little influence outside the interval(large or small).
作者
罗刚
张玉龙
潘少康
贾航航
刘畅
LUO Gang;ZHANG Yulong;PAN Shaokang;JIA Hanghang;LIU Chang(School of Highway,Chang’an University,Xi’an 710064,P.R.China)
出处
《应用数学和力学》
CSCD
北大核心
2020年第5期467-479,共13页
Applied Mathematics and Mechanics
基金
国家自然科学基金(51708042)
陕西省自然科学基金(2019JQ⁃008)。
