Exploring the rock failure mechanism from an energy perspective is crucial for ensuring the safe construction of tunnels under complex geological conditions. In this study, a progressive damage and failure model of rock elements is established using the strain-energy-density theory based on the thermodynamic theory. Specifically, the rock elements are considered to have failed when the strain energy density absorbed by the element is greater than the critical strain energy density. Besides, the damage evolution of rock elements is reflected through the reduction of elastic modulus, until the element only has a certain residual strength. Based on the above theory, the calculation program of rock damage and failure is developed in FLAC3D using the FISH language. The validity of the method for simulating the process of rock damage and failure is verified through the numerical simulation of Brazilian splitting tests. Finally, the model was applied to the overload test of the geo-mechanical model of the Liangshui Tunnel on Lanzhou-Chongqing Railway. The comparison between the numerical simulation and the test results has not only confirmed that the feasibility and accuracy of the model in simulating the progressive failure process of tunnel surrounding rock under high ground stress, but also its ability to visually display the damage degree, failure scope and evolution process of the surrounding rock. The research findings are of great significance in ensuring the safe construction of tunnel and will promote the efficient development of the underground engineering construction.
Abstract Exploring the rock failure mechanism from an energy perspective is crucial for ensuring the safe construction of tunnels under complex geological conditions. In this study, [...]
'''Recently, reinforced concrete beams strengthened with carbon fiber reinforced polymers (CFRP) have been widespread. The objective of this research is to calculate the shear strength capacity increment of reinforced concrete beams strengthened by CFRP strips. The ABAQUS software was used to construct a model of the finite elements for beam simulation. Six beams were generated in ABAQUS software, two were control beams and the remaining four were reinforced by varying CFRP strips. All beams had the same rectangular cross-section geometry and length. The obtain results showed that CFRP can significantly increase the shear capacity of the beam. And the highest load and deflection is a little affected by the CFRP strips orientation. This study can proposes a more economical way for existing structures to improve the carrying capacity.
Abstract '''Recently, reinforced concrete beams strengthened with carbon fiber reinforced polymers (CFRP) have been widespread. The objective of this research is to calculate [...]
Numerical modeling of progressive damage and failure of tunnels deeply-buried in rock considering the strain-energy-density theory 
