遮弹层厚度对砂土中地冲击荷载的影响  

Influence of Thickness of Anti-Penetration Layer on Ground Shock Load in Sand

作　　者：洪智捷 洪建 杨耀宗 HONG Zhijie;HONG Jian;YANG Yaozong(College of National Defense Engineering,Army Engineering University of PLA,Nanjing 210007,China)

机构地区：[1]陆军工程大学国防工程学院,江苏南京210007

出　　处：《陆军工程大学学报》2023年第5期60-67,共8页Journal of Army Engineering University of PLA

基　　金：国家自然科学基金(52178515)。

摘　　要：土中自由场地冲击荷载是地下防护结构设计的基础。分别建立炸药在砂土和遮弹层中爆炸的精细化数值模型,对比分析所得地冲击荷载的计算结果与相关试验数据。在遮弹层爆炸模型中,改变遮弹层厚度,研究遮弹层比例厚度对地冲击荷载衰减及分布规律的影响。结果表明,两个模型的数值计算与试验数值吻合较好,验证了数值计算方法的可靠性。遮弹层比例厚度不改变爆心正下方地冲击应力峰值衰减系数,但对应力峰值大小有影响;遮弹层比例厚度越大,爆心正下方土中相同比例深度处的应力峰值越大。地冲击荷载水平分布也受遮弹层的影响,遮弹层比例厚度越大,距遮弹层底面比例距离大于0.15 m/kg^(1/3)的平面上归一化竖向应力水平分布曲线越陡,进而得出考虑遮弹层厚度影响的地冲击荷载计算公式。Free-field ground shock in soil is the basis of underground protective structure design.Firstly,two refined numerical models are established respectively for explosion in soil and explosion in antipenetration layer.Secondly,the calculation results of the ground shock load are compared with the relevant test data to verify the reliability of the numerical methods.Thirdly,in the numerical model for explosion in anti-penetration layer,the influence of the scaled thickness of anti-penetration layer on the attenuation and distribution of the ground shock load is explored by changing the thickness of anti-penetration layer.The results show that the calculation results of the two models agree well with relevant test data,which proves the high reliability of the numerical calculation methods;the thickness of the anti-penetration layer does not change the attenuation coefficient of the ground shock peak stress directly below the explosion center,but has an effect on its values;the thicker the anti-penetration layer is,the greater the peak stress at the same depth in the soil;the horizontal distribution of ground shock load is also affected by the anti-penetration layer;when the thickness of the anti-penetration layer increases,on planes which are more than 0.15 m/kg^(1/3)away from the bottom of the anti-penetration layer,the curve of horizontal distribution of normalized vertical stress becomes steeper.Finally,the calculation formula of ground shock load considering the influence of the thickness of anti-penetration layer has been drawn.

关 键 词：遮弹层比例厚度 地冲击荷载 传播衰减规律 归一化水平分布规律 

分 类 号：O382[理学—流体力学]