为研究冲击荷载作用下泥石流堆积体力学响应特征,采用堆积体土工试验、冲击荷载作用相似模型实验和数值模拟相结合的方法,研究了圆柱弹体侵彻泥石流堆积体的加速度、速度、位移、应力等时程曲线以及弹体侵彻过程中的运动姿态、阻力和空腔特征演化规律。结果表明,弹体侵彻泥石流堆积体时,位移增加较快,随着弹体在泥石流堆积体中运动姿态的失稳,其减加速度逐渐增加,在弹体轴向与其运动方向垂直时,接触面最大,阻力达到最大值,负加速度也达到最大值,在弹体的侵彻过程中,弹体将泥石流堆积体向四周排开,形成大的空腔,弹体速度随之降低,位移增加趋于缓慢。弹体侵彻过程中,随着时间的增加,弹体翻转,最后尾部开始向前与泥石流堆积体接触面减小,阻力降低,加速度减小,速度相对减缓,位移曲线的曲率随着速度的减小而减小。研究结果可为高速列车冲击泥石流堆积体力学响应特征方面的设计和安全评估提供重要材料模型数据支持。

In order to study the mechanical response characteristics of debris flow deposits under the impact load of high-speed projectiles, the time-history curves of acceleration, velocity, displacement and stress of projectiles penetrating debris flow deposits were analyzed by means of impact load model experiment and numerical simulation. The characteristics of motion attitude, resistance and cavity in the process of projectile penetration were analyzed. The experimental results show that when the projectile penetrates the debris flow deposit, the displacement increases rapidly. With the instability of the motion attitude of the projectile in the debris flow deposit, the deceleration gradually increases. When the axial direction of the projectile is perpendicular to its motion direction, the contact surface is the largest, the resistance reaches the maximum, and the negative acceleration also reaches the maximum. During the penetration process of the projectile, the projectile arranges the debris flow deposit around to form a large cavity, and the velocity of the projectile decreases and the displacement increases slowly. During the penetration process of the projectile, with the increase of time, the projectile flips over, and finally the tail begins to move forward. The contact surface between the debris flow accumulation body and the debris flow accumulation body decreases, the resistance decreases, the acceleration decreases, the speed is relatively slow, and the curvature of the displacement curve decreases with the decrease of the speed. The research results can provide important reference and theoretical support for the design and safety assessment of high-speed projectiles in the mechanical response characteristics of debris flow deposits.

TU375.4

,国家自然科学(Nos.52104088, 52225404)；2021年度辽宁省教育厅科学研究经费项目(面上项目)(No. LJKZ0361).,国家自然科学基金项目（面上项目，重点项目，重大项目）,国家自然科学基金项目（面上项目，重点项目，重大项目）