悬垂弹射自适应底座附加载荷变化机理研究

自适应底座的附加载荷是悬垂弹射系统的重要设计参数之一。为研究自适应底座在悬垂弹射时附加载荷的产生与变化机理，建立了自适应底座附加载荷的数学模型，推导附加载荷的微分与积分表达式，获得影响附加载荷的主要因素：底座的内压强、上端面的水平投影面积、触地区域的水平投影面积。通过数值模型对附加载荷理论公式进行了验证，解析解与数值解吻合较好，相对误差最大不超过1.9%. 依据附加载荷积分公式，研究积分区域与附加载荷表现形式之间的关系，结果表明：附加载荷的方向与积分区域类型存在对应关系，可能出现局部作用方向相反的情况。当地基下沉量不大或出现局部剪切破坏时，附加载荷有可能不变；而地基下沉量较大时，附加载荷的幅值和方向可能均会变化。自适应底座的附加载荷是悬垂弹射系统的重要设计参数之一。为研究自适应底座在悬垂弹射时附加载荷的产生与变化机理，建立了自适应底座附加载荷的数学模型，推导附加载荷的微分与积分表达式，获得影响附加载荷的主要因素：底座的内压强、上端面的水平投影面积、触地区域的水平投影面积。通过数值模型对附加载荷理论公式进行了验证，解析解与数值解吻合较好，相对误差最大不超过1.9%. 依据附加载荷积分公式，研究积分区域与附加载荷表现形式之间的关系，结果表明：附加载荷的方向与积分区域类型存在对应关系，可能出现局部作用方向相反的情况。当地基下沉量不大或出现局部剪切破坏时，附加载荷有可能不变；而地基下沉量较大时，附加载荷的幅值和方向可能均会变化。

Research on Variation Mechanism of Additional Load of Adaptive Base during Drape Ejection

To research the formation and variation mechanism of the additional load, a mathematical model of the additional load is established, and the differential and integral formula of additional load are derived. The main factors which affect the additional load are obtained, such as pressure in adaptive base, horizontal projected area of upper face, and horizontal projected area of touchdown zone. The theoretical formula of additional load is verified by the numerical model. The analytical solution is well consistent with the numerical solution, and the relevant error is less than 1.9%. The relationship between the integral area and the expression form of the additional load is studied according to the integral formula of the additional load. The results indicate that there exists corresponding relationship between the direction of the additional load and the kind of the integral area, and that situation of that the direction is opposite in some areas may happen. When the ground subsidence is small or the shear failure exists in some area, the additional load may stays the same. When the ground subsidence is large, the amplitude and direction of the additional load may change.