In order to evaluate the crack resistance of concrete gravity dams in service,the fracture properties and the tensile-softening constitutive of concrete after compressive creep was investigated.Firstly,compressive creep test was conducted on concrete prism under the stress level of 40%of the uniaxial compressive strength until 360 days.Then,after the compressive creep test,three-point bending fracture test was conducted under quasi-static loading to measure the initial fracture toughness,unstable fracture toughness,and fracture energy.Finally,the improved J-interval meth-od was introduced to calculate the energy consumed for crack propagation,further,derive the softening constitutive re-lationship.The experimental results indicated that,after the compressive creep test,compressive strength,tensile strength,and elastic modulus increase,and the initial fracture toughness,unstable fracture toughness,and fracture en-ergy increase.In addition,compressive creep has significant influence on the softening constitutive relationship of con-crete.Stress-free crack opening displacement decreases largely,indicating the stronger brittleness after the compressive creep test.
维普
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