Chuansheng Xiong

Influence of anion types on the electrodeposition healing effect of concrete cracks

With the zinc salt and magnesium salt solutions, the influence of anion types on the electrodeposition healing effect of concrete cracks was investigated, four parameters such as rate of weight gain, surface coating, crack closure, and crack filling depth were measured, and the mineral composition and appearance of electrodeposits in the cracks were analyzed. The experimental results demonstrate that the electrodeposition healing effect is the best by adopting ZnSO4 and MgSO4 solutions. The mineral composition of electrodeposits in the cracks does not change with the anion types. The most particles of ZnO crystal appear as fusiform by using zinc salt solutions. If we selected MgSO4 solution, the Mg(OH)2 crystal was porous honeycomb. The electrodeposits present as flake structure while the other magnesium salt solutions were adopted.

Evaluation research on applicability of rapid iodide migration test

The applicability of the rapid iodide migration test was systematically studied. Comparative experimental tests of different test conditions, including several external voltages, test durations, concrete ages and mixing proportions, were carried out to make clear the transport behaviors of iodide under parallel electric fields. Numerical simulations were also done using the finite element method to found the correlation between chloride and iodide transport behaviors. The test and numerical results show that the chloride transport behaviors of RIM and RCM tests have a good correlation under the several conditions used in the present paper. Moreover, the influence of external conditions (external voltages, test durations) on the test results is small. Thus, it can be concluded that the RIM method is available to determine the chloride penetration resistance of the chloride-eroded structural concrete.