Experimental Research On Anti-corrosion Measures Of High Performance Concrete In Saline-lake Environment

In order to solve the anti-corrosion problem of reinforced concrete bridge in Cha Er Han Salt Lake area, we choose the cementitious capillary crystalline waterproofing materials (XYPEX) as anti-corrosion measure. Through a series of tests, such as indoor complete immersion test and dry-wet cycle test, its antiseptic effect has been studied in this thesis. The results will promote it extended and spread in practical project.This paper describes a experimental comparison reseach carried out to examine the performance of various high performance concrete, such as high performance concrete inside XYPEX(NHPC), and exterior coated with XYPEX(WHPC), and high performance concrete(HPC). Based on geotechnical engineering prospecting report of Cha Er Han Salt Lake area, we choose clear water,10% sodium chloride solution,5% magnesium sulfate solution,10% sodium chloride solution+5% magnesium sulfate solution and simulating high concentration salt lake brine as different corrosion conditions.They are tested by single factor experiment of salt erosion, and double effect experiment of salt erosion & dry-wet cycle, through a series of evaluation parameters include relative dynamic modulus of elasticity, loss weight and appearance change of concrete.The single factor experimental lasting 8 months results show that relative dynamic modulus of elasticity and loss weight change very little between NHPC and WHPC, without remarkable effect. However, WHPC has better protective effect in respect of appearance change of concrete.The double effect experimental results show that the higher ion concentration in salt solution is, the more serious corrosion extent becomes,affected by the salt erosion and dry-wet cycle mutually, In the worse case, dry-wet cycles aggravate salt crystallization expansion pressure, quickening the destroy of concrete. The results further show that HPC itself has some ability to resist corrosion. For example, after 240 cycles in the brine, HPC still doesn't meet the test standard of failure.In the respect of the relative dynamic modulus of elasticity, XYPEX has obvious effects. In the respect of loss weight, with the increased corrosivity in solution, concrete samples lose more weight, with HPC and NHPC samples mainly peeling cement paste,and WHPC samples peeling coating. In the respect of appearance change of concrete, XYPEX serves as a good isolation for concrete from outside conditions.In this thesis, preliminary experimental research on the cementitious capillary crystalline waterproofing materials (XYPEX) as anticorrosion measure in saline-lake area is conducted, which makes certain achievement in this respect. But the results are only experimental and probably not appropriate for bad saline-lake environment. And it is important to conduct further research on test and verify the results in actual environment.