doi:

DOI: 10.3724/SP.J.1249.2018.04398

Journal of Shenzhen University Science and Engineering (深圳大学学报理工版) 2018/35:4 PP.398-404

Deformation and microstructure characteristics of clays under traffic loading


Abstract:
In order to study the deformation properties and the microstructure characteristics of clays under traffic loads, we perform dynamic triaxial tests on clays from the Qianhai Area, Shenzhen. After the dynamic triaxial test, we slice the samples and scan the slices by scanning electron microscope to perform qualitative analysis and quantitative study of microstructure to interpret deformation mechanism. The results show that the critical cyclic stress ratios change with the test conditions. With the increase of confining pressure and the decrease of vibration frequency, the critical cyclic stress ratios decrease. When the cyclic stress ratio is less than the critical value, with the increase of cyclic stress ratio, pores are compressed and axial accumulative strain trends to increase. Axial accumulative strain decreases with the increasing of vibration frequency and confining pressure under the same of cyclic stress ratio. However, if the cyclic stress ratios are greater than the critical one, particles of the samples rearrange, the pore area expands and flattens intensively, and the structure of sample is broken consequently.

Key words:soil mechanics,clay,dynamic load,axial strain,microstructure,dynamic triaxial test

ReleaseDate:2018-07-26 10:51:03



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