Abstract: Concrete dams in cold regions with overdue heat preservation maintaining measures, or with poor construction conditions, would possibly suffer from frost damage during concrete construction, thus bring about changes to parameters of the dam. A multipoint hybrid model is established to invert the modulus of elasticity of frost damage concrete dam by improving ordinary single-point hybrid model. Linearly constrained optimization algorithm is employed to constrain the range of elastic modulus adjustment coefficient for the fitting calculation, and some measuring points with high precision are selected for the model. According to case study result of a concrete gravity dam, the multiple correlation coefficients of the multipoint hybrid model is above 0.98, barely different from the result of single-point hybrid model. The conclusions suggest that the proposed multipoint hybrid model is feasible in the back analysis of parameters of frost damage concrete dam.

Key words: frost damage concrete, elasticity modulus, multipoint hybrid model, linearly constrained optimization algorithm, heat preservation measure, joint inversion