复杂应力下强风化软岩湿化变形试验研究

EXPERIMENTAL STUDY ON SLAKING DEFORMATION OF INTENSE WEATHERING SOFT ROCK UNDER COMPLICATED STRESS CONDITIONS

强风化软岩用于高等级公路路基填筑时,压实特性和湿化变形特性是评价填料性能的主要指标。对填料在不同压实度下进行承载比试验,试验结果表明,承载比值随填料压实度的增大而增大。利用室内三轴剪切仪对强风化软岩进行干、湿双线平行试验和在复杂应力状态下不同压实度的湿化变形试验,试验结果表明,填料在压实度为90%且有较大的偏应作用下,湿化不仅产生较大的附加轴向应变,而且还能引起相当大的附加体积应变和偏应变。因此,提高路基填土的压实度是减少湿化变形的关键因素。

When using intense weathering soft rock to fill high grade highway embankment, compaction characters and wetting deformation characters are the major indices to estimate the filling performance. The CBR experiments under different compaction degrees showed that the CBR value increased with the filling compaction degree increase. Triaxial shear apparatus was used to conduct dry-wet double-line parallel experiment and wetting deformation experiment of different compactions under complicated stress conditions. The result shows when the compaction degree reaches to 90% with rather high deviatoric stress, wetting can not only generate high additional axial deformation, but also cause high additional volumetric strain and deviatoric deformation. Increasing compaction degree of the filling is the key factor to decrease wetting deformation.