Static And Dynamic Mechanical Properties Of Concrete In The Pavement Of The Airport Under Environmental Effects

The concrete in the pavement of the airport is damaged by the impact caused in the process oftaking off and landing of the airplane. Meanwhile, due to the different circumstance of the airportpavement, the concrete is also damaged by different environment. This thesis will focus on thedynamic mechanical properties of concrete under the influence of different environment.This thesis chooses5different mix proportions of concrete: C (high strength concrete), H (highperformance concrete), GH1, GH2, GH3(three groups of hybrid fiber reinforced concrete). Accordingto the different circumstance of the airport, it will simulate8environmental conditions, and do asingle test(10%NaCl solution erosion,5%MgSO4solution erosion, water freezing and atmosphericcarbon), a double test (freeze thawing+10%NaCl solution erosion, freeze thawing+5%MgSO4solution erosion,10%NaC1+5%MgSO4solution erosion), and multiple test(freeze thawing+10%NaCl+5%MgSO4solution erosion) to the test-pieces of concrete with different mix proportions.With the YES-1000digital display type pressure testing machine and75mm Split Hopkinsonpressure bar (SHPB) device, the basic mechanical parameters and the stress-strain curve is obtainedthrough the study of static and dynamic mechanical properties to the test-pieces of concreteinfluenced by environment. With the analysis of the influence of environment on dynamic and staticmechanical properties and failure pattern of concrete, and based on the experimental curves in static,the thesis will choose constitutive equation recommended by Yang Muqiu to do numerical fitting tothe stress-strain curves influenced by environment, and in shock compression experiment curve,based on the modified ZWT constitutive model, it will also do the dynamic numerical fitting tostress-strain curves influenced by environment.Results show that：1. Under the influence of environment, the compressive strength and modulus of elasticity of concretewith different mix proportions reduce with different degrees.2. In the static compression experiments, the damage degree of the concrete with different mixproportion in freezing and thawing environment is lower than that in carbonization environment.3. In the impact compression experiments, it comes to the rule that: in group H, the damage degree ofthe pressure resistance of the concrete with high performance under the freezing and thawingenvironment is higher than that of the impact elastic modulus, and in other groups, it is lower than thedamage degree of impact elastic modulus. The damage degree of concrete with different mix proportion under the single erosive attack of chlorine is higher than that under the double effect ofchlorine erosion and freezing thawing; the damage degree under the single erosive attack of sulfate islower than that in the double effect of sulfate erosion and freezing and thawing; the damage degreeunder the double effect of chlorine and sulfate is higher than that under the triple effect of chlorine,sulfate and freezing and thawing. Among the damage degrees, that in carbonization environmentcounts the least, that under the double effect of chlorine and sulfate counts the most.