Application Of Strain Softening Mohr-Coulomb Model In Adobe Masonry

In this era of increasingly sharp relationship between architecture and the environment,boring buildings are still widely used by many countries because of their green environmental characteristics.In order to meet the requirements of reliability and durability of adobe masonry buildings,its mechanical properties are worthy of further exploration and practice.Through basic mechanical tests,it is found that under the action of external load,when the adobe masonry reaches the strength limit,the material will undergo obvious strain softening.According to this phenomenon,the following work is carried out:(1)In the analysis of mechanical properties of adobe masonry,based on the elastoplastic theory,the post-peak part of the stress-strain curve is regarded as nonlinear,and the Mohr-Coulomb condition is selected as the yield condition,assuming that the strength parameter cohesion is constant with the softening parameter equivalent plastic strain Evolution,so as to obtain a piecewise linear function relationship between the two,since the internal friction angle changes little before and after softening of the material,in order to simplify the analysis,it is assumed that the internal friction angle is always constant,and the strain softening model is combined with the Mohr-Coulomb constitutive a new constitutive model.(2)According to the piecewise linear function of strength parameters and strain softening parameters,the evolution law of cohesive force with softening parameters is specified,and the strain softening law of adobe masonry in the plastic column of Mohr-Coulomb model is determined.The adobe masonry was modeled separately and separately.After numerical simulation,the experimental phenomena and load-displacement curves were compared and analyzed.It was observed that the model was in good agreement with the experimental results,which indicated that the parameters used in the simulation were more Reasonable,it is feasible to compare the adobe masonry to the geotechnical material and apply the model to the numerical analysis of adobe masonry.(3)After the numerical simulation analysis of the quasi-static test of the plain soil wall,the simulation results are compared with the experimental phenomena.The numerical simulation can basically predict the shear failure trend of the structure.The numerical analysis of different height-thickness ratio models of two groups of adobe masonry walls is carried out.It is found that for the adobe structure,the higher the aspect ratio,the worse the peak strength and energy consumption of the structure,and the wall will show more.Obvious instability and damage,the analysis shows that the height-thickness ratio of the adobe wall should not be too large.(4)The numerical simulation analysis of the adobe shell push test is carried out by using the parameters mentioned above in the Mohr-Coulomb model of the softening.The simulation results show that the model can basically predict the final bearing capacity of the structvure,indicating that the model can used in adobe structures.