SIMULATION OF ANALYSIS CHANGSHA ARCH DAM WITH MgO-CONCRETE

摘要

Mgo Concrete is a kind of slightly expansive concrete which is used in Chinese dam engineering more and more widely. To evaluate the effects of autogenous expansion on the stresses of arch dams, a simple model of autogenous expansion for Mgo Concrete in dam engineering is presented. This model is based on three presumptions: (1) The total amount of autogenous expansion of Mgo Concrete is related only to the properties of materials and mixing of concrete, especially the amount of Mgo in unit volume concrete. (2) The autogenous expansion of Mgo Concrete is irreversible due to the irreversibility of hydration reaction of Mgo in the concrete. (3) The autogenous expansion strain rates of Mgo Concrete are in proportion to the rates of hydration reaction of Mgo in concrete and the rates of hydration reaction of Mgo bear a relation with to temperature and residual Mgo in unit volume concrete. The model is verified by some experimental data of autogenous expansion of Mgo Concrete and field-measured data of an arch dam in China. Embedded into a finite element arch dam simulation software, this model is employed to simulate the effects of autogenous expansion of Mgo Concrete in the dam engineering.