Study On The Durability Of HPC Under Combined Action Of Damage Factors

At present, the concrete resistance to sulfate attack has become a research focus in civil engineering and hydraulic engineering at home and abroad. The GB/ T50082-2009 promulgated on July 2010 emphasized and added the test method of concrete resistance to sulphate attack. In this paper, some issues were researched on a series of tests.Firstly, the durability loading device relied on visual inspection in the past for the number of turnning the screw to lead to lots of tedious tests. So it was re-designed and improved through introducing HDW202 weighing sensor, which can help to apply bending stress accurately. The durability loading device had many advantages such as small size, corrosion resistance, simple operation, and so on . It can be placed in the oven or freeze-thaw box, contributing to the durability tests under combined action of damage factors.Secondly, Strength Corrosive Coefficient, The Relative dynamic elastic modulus (Erd) and Mass Loss Rate were selected with different content of fly ash, different concentration of sulfate solutions and different size of bending stress to evaluate the durability of High Performance Concrete, namely HPC, in the resistance to sulfate attack. The three-indicators damage model were established for life prediction of concrete based on experimental data.Finally, based on the second Fick law , finite difference method were adopted to take the one-dimensional numerical simulation of sulfuric acid root ions eroding the concrete, and then the contrast of simulation results conform to the experimental results.Some theory foundation would be provided for the subsequent HPC resisting sulphate erosion in this paper. At the same time the established life prediction model and numerical model can also be applied to predict the concrete construction life of actual engineering such as dam, tunnel, pier and docks, and so on.