建立了“双重替代结构”新概念，并在“相对可靠度理论”的基础上与迭代设计方法结合起来，提出了考虑整体可靠度的直接基于位移的抗震设计方法。该方法采用“相对可靠度理论”确定与给定性态目标对应的具有明确可靠度含义的位移目标，其基于位移的迭代设计过程则利用“双重替代结构”将位移目标精确地转化为对应的基底剪力目标，并通过基底剪力调整因子得到修正后的基底剪力设计值，经迭代计算完成抗震设计。最后，通过系列算例验证了该直接基于位移的抗震设计方法的有效性，其能够实现对结构位移目标和整体可靠度的精确有效控制。

A new concept of“double substitute structure”was established, combining the new concept with the basic iterative process, a new direct displacement based seismic design method considering global reliability was proposed.This new iterative design method use“relative reliability theory”to determine the displacement target corresponding to the given performance objectives, and transform the displacement target into corresponding base shear target precisely by“double substitute structure”, then calculate the exact designing base shear force to finish the iterative seismic design process by introducing a correction factor. The calculation examples showed that the new direct displacement based seismic design method can accurately control the displacement response of structure in the sense of global reliability.