Test Research Of Properties On Rebounded Deformation And Pore Water Pressure Of Soft Clay Under Unloading Condition

Soil will cause deformation under load ,and rebound deformation will occur when unloading. There is great discrepancy in the properties of soft soil when loading and unloading. Based on predecessor's foundation, triaxial apparatus were improved due to requirements of the tests.The consolidation tests, rebounded deformation tests and pore water suction tests could be carried out.The relationships between rebounded deformation and time, between unload ratios and void ratio,between the maximum rebounded deformation were researched thought the improved triaxial apparatus.The result showed that the soft soil in Wuhan area existed two critical unload ratios that was 0.4 and 0.9.When the soft soil's unload ratio 00.9, rebounded deformation of the soft soil would not happen ,no matter what the pre-consolidation load was.When 0.30.9, the water that leaved the soft soil during consolidation would not be drawn back to the soil;When 0.3