A uniform risk loss model are defined, and a basic loss estimate method is also proposed, which is composed of loss extent model, loss value conversion model, loss time value model. 建立了统一的桥梁风险损失概念模型,提出了由损失幅度模型、损失价值转换函数、损失时间价值模型三个基本模型组成的桥梁风险损失量测的通用方法。