Seismic Response Analysis Of Concrete Structures Considering Corrosion Damage Of Bottom Column In Marine Environment

Concrete structure, Servicing in marine environment, not only withstand high winds, earthquakes and wave loads, also suffered from physical and chemical erosion of the environmental factors such as sulfates and chlorides, The safety and durability of the concrete structure under loads and environmental factors are hot issues of civil engineering research. In order to assess the seismic performance of concrete structure in marine environment, based on considering time-dependent corrosion constitutive model of concrete and the mechanical properties of corroded steel bars, using the OpenSEES software platform, Won the eismic response of concrete structure which’s underlying column-corrosion damage caused by marine environment is taken into consideration, time-varying rules of of concrete-structure’s seismic behavior in marine corrosion process are analyzed. Main contents and results include:(1) Firstly, based on damage of concrete under sulfate corrosion degradation mechanisms, the variation of characteristic parameters of concrete constitutive with erosion sulfate concentrations and the erosion of time has been discovered in the corrosion process, Basing on the Scott-Kent-Park constitutive model of concrete, time-dependent constitutive model of concrete has been established under the process of sulfate corrosion.(2) Secondly, Using transmission model of chloride ions in concrete and chloride ion corrosion threshold equation, Giving calculation method of initial rust time of the reinforcement, According to reinforcement corrosion and pitting corrosion-rate model, effective sectional area calculation method of the Rebar is established, based on the constitutive model of reinforced, mechanical properties calculation model of corroded steel bars under chlorine salt erosion finally Given.(3) Then using fiber model of OpenSEES, mechanical analysis model of the concrete column under sulfate and chlorine salt has been established. Time-varying regularity of the corrosion process of bearing capacity of concrete change, stress redistribution and the column of hysteretic and skeleton curve have been analysis under the corrosion process. Won the mechanical behavior variation of concrete columns with the time of corrosion, results show that, with the time corrosion increase,the mechanical behavior of concrete columns come down.(4) Last, Earthquake response analysis model of concrete framework structure which’s bottom columns corrosion injury has been established, and taking structure top layer displacement, and layer between maximum displacement, and layer between maximum displacement angle and column maximum cut force into consideration, Using software OpenSEES for platform, analysis the response of the concrete structure having corrosion under often met and rare met earthquake, giving the seismic performance changed by corrosion time of the concrete framework structure results showed that, With the increase of corrosion, and seismic performance of RC frame structure become lower.