Kaifeng H.,Institute of Seismology |
Kaifeng H.,Wuhan Earthquake Engineering Research Institute co. |
Xutao W.,Wuhan Earthquake Engineering Research Institute co. |
Zhongping Z.,The Second Architectural Design Institute of Xiangyang City |
And 2 more authors.
Electronic Journal of Geotechnical Engineering | Year: 2014
The core sampling was taken in some slate tunnels of Wuhan-Guangzhou high-speed railway, and the swelling characteristics test was carried out based on the work. In the test, the relationship of the expansion rate with water adsorption time, water adsorption and stress states in slate was respectively analyzed. By fitting, the law of expansion rate under lateral restraint with time was obtained. Then the research results of other domestic scholars and the fitting law were taken into the calculation, the relation between the expansion rate of slate and water absorption was deduced. Comprehensively considering the influence of water adsorption and stress state on swelling deformation and introducing the time effect, the swelling constitutive equation of slate was established, and the law in the constitutive equation showed the consistency with the mechanics form of slate in practical engineering. The results indicated that: the expansion rate of slate under lateral restraint showed the exponential relationship with absorption time, and with the increase of axial load, the axial expansion showed the decrease with negative logarithmic function. When the angle between the structural surface of soft slate and the axial direction of the sample changed from 0 °~90 °, the expansion rate of slate decreased with the increase of the angle. Finally, the mechanism of swelling characteristics in slate was correlatively analyzed from the microscopic view, providing a demonstration for the conclusions of swelling test. © 2014 ejge.
Qinga H.,Institute of Seismology |
Qinga H.,Wuhan Earthquake Engineering Research Institute co. |
Yic L.,Hubei Electrical Power Survey and Design Institute |
Yia Z.,Institute of Seismology |
And 3 more authors.
Electronic Journal of Geotechnical Engineering | Year: 2015
Soil liquefaction is a major cause of site damage during earthquakes. Based on in-situ tests, the influence of the saturated silt for liquefaction estimation were studied in Wuhan area. Then the dynamic properties and liquefaction mechanism of the saturated silt were illuminated by dynamic triaxial test. According to the test, the development law of pore water pressure of the saturated silt were analyzed. It shows the value of water pore pressure tends to be stable when it is equal to about 90 % of confining pressure, and the corresponding value of double amplitude strain is 5 %. Therefore, these values may be used as the indexes of liquefaction evaluation. Also the relationship between the dynamic shear stress ratio and the number of soil cycles were obtained. Then the liquefaction condition was estimated of the saturated silt with shear stress liquefaction discrimination method at different depths and different seismic intensities in Wuhan area. © 2015 ejge.