一、前言荷载组合,准确地说,应是荷载效应的组合,即不同类型荷载对结构的某一部件的某一截面所产生的效应的组合。不同方向、不同性质的荷载要转化为荷载效应后才能组合,而不是简单的叠加。荷载组合实质上是荷载相遇问题。只有相遇的荷载才能同时对结构的某一部件的某一截面产生某种效应。由于作用在结构上的许多荷载都具有随机性质,不仅在空间上是随机的,而且在时间上也是随机的,即其出现率ν(每年多少次)、出现持续时间τ(几 I. INTRODUCTION The load combination, to be precise, should be a combination of load effects, that is, a combination of the effects of different types of loads on a section of a component of a structure. Loads in different directions and with different properties must be converted into load effects before they can be combined instead of simply superimposed. The load combination is essentially a load encounter problem. Only the load that meets can have some effect on a section of a part of the structure at the same time. Since many of the loads acting on the structure are of random nature, they are not only spatially random, but also random in time, ie, their occurrence rate ν (how many times per year), and the duration τ (several