Experimental Study Of Coral Sand Concrete Under Uniaxial And Biaxial Compression

The number of construction projects in the far sea area has gradually increased,and coral reef sand concrete is easy to get as local materials,speeding up the construction speed,increasing indemnity capabilities,and reducing construction and maintenance costs.However,the change of the main material composition will inevitably affect the mechanical properties of the material,especially in the complex environment in the marine area,and it need higher requirements for its mechanical properties.The severe environment requires the designer to have a deeper understanding of the mechanical properties of the concrete,and has a clear understanding of the damage behavior and development of the material.At the same time,complex mechanical analysis requires a more effective multi-axial material model.At present,the ordinary concrete has been subjected to a relatively experimental study on the damage behavior based on acoustic emission,and a number of multi-axial mechanical properties tests and theoretical studies have also been conducted.However,there is no effective research for coral reef sand,a new building material.In this paper,the mechanical properties of coral reef sand concrete under uniaxial and biaxial compression are described from two aspects of mechanical loading test and acoustic emission test.The main results of the test were as follows:(1)The full curves of the coral reef sand concrete subjected to uniaxial and biaxial compression are obtained.The characteristics of the changes in each stage are described separately,and the stress-strain constitutive equations of the entire load process are constructed.(2)Acoustic emission characteristic parameters of coral reef sand concrete under different stress ratios were obtained.The development of cracks in the loading process was studied and the acoustic emission activity function was established to provide basis for subsequent damage evolution research.(3)Through the comparative test of concrete with different water cement ratio,the change law of increasing concrete strength with water cement ratio was obtained;through the comparative test of concrete with different mix ratio under different stress ratios,the stress ratio biaxial resistance was obtained.(4)The damage evolution equation describing each concrete ratio is obtained,including Weibull equation and Ramberg-Osgood equation.(5)The failure criteria of coral reef sand concrete under biaxial loading was obtained.(6)The damage evolution equation of the concrete under biaxial compression was obtained by acoustic emission test.