考虑载荷大小和方向不确定性的柔顺度期望和方差的解析公式。在载荷大小和方向都服从正态分布的前提下，研究了具有不确定性荷载的柔顺度期望和方差的解析求解方法，将结构柔顺度表示成确定性荷载对应的互柔顺度与荷载大小和方向正余弦乘积之和的形式，将均值与方差的计算，转化成荷载大小乘积的均值以及方向角度的三角函数的幂函数或乘积的均值问题。(An analytical formula for the expectation and variance of flexibility in consideration of the uncertainty of the load size and direction. In the load magnitude and direction are subject to the premise of the normal distribution, the analytical method for solving the softness of expectation and variance with uncertain load, the structure flexibility expressed as deterministic loads corresponding to the cross compliance and load magnitude and direction cosine and the product of the form, the calculation of mean and variance. Into the mean load of trigonometric function of the mean and the direction angle of the product or the product of the power function.)