فهرست مقالات Effective stress

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  1 - A Parametric Study of Interactions Between Liquefaction Sand Lenses and Shallow Tunnels Under Earthquake Loads
  Mohammad Shabani Soltan Moradi Mohammad Azadi Homayoon Jahanian
  10.22094/jseg.2023.1967504.1122
  If the saturated sand lenses are placed around the tunnels under the force of the earthquake, liquefaction will occur in them. This will cause settlement of the ground surface and changes in forces and anchors on the tunnel lining. For this purpose, it is important to e چکیده کامل

  If the saturated sand lenses are placed around the tunnels under the force of the earthquake, liquefaction will occur in them. This will cause settlement of the ground surface and changes in forces and anchors on the tunnel lining. For this purpose, it is important to evaluate the change of different parameters of the sand lens and the change of the thickness of the tunnel lining in the part of the sand lens and the changes in the diameter and depth of the tunnel as well as the location of the sand lens considering the tunnel inside it. Therefore, this article investigates the mentioned changes in shallow tunnels in the location of sand lens in flowing soils surrounded by clay. In this article, FLAC 3D software is used to determine changes in pore water pressure and effective stress reduction after sand lens liquefaction. Based on the obtained results, if the sand lenses are placed at a depth of less than 10 meters, they increase the land surface subsidence by 36% compared to the reference model B, with an increase of 2 meters in the depth of the sand lens compared to the reference model B, the value of the maximum bending anchor and axial force on the tunnel lining increases by 35.7% and 14.4%, respectively, in the sand lens part. The findings of the present study can be very useful in the decision-making process of tunnels that are dug inside flowing sand lenses. پرونده مقاله
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  2 - Land-subsidence relative to Pore-pressure and Effective Stress (Case study: Khorramabad Plain, southwestern Iran)
  Zahra Kamali Hojat Mirzavand Jafar Rahnamarad
  Phenomena of land subsidence, increasing the effective stress (σ1) of the body of aquifer sediments have not consolidated. Because the weight of the upper overburden aquifer sediments by the solid and the fluid contained in the pore space to be tolerated when the چکیده کامل

  Phenomena of land subsidence, increasing the effective stress (σ1) of the body of aquifer sediments have not consolidated. Because the weight of the upper overburden aquifer sediments by the solid and the fluid contained in the pore space to be tolerated when the fluid pressure caused by drop in the water table the decrease in the effective stress increased this results in soil compaction and evidence of subsidence in the area, Such as tensile cracks, crack growth in civil structures tube wells in plain. The last few years Bagstrsh, Land subsidence caused major problems for the agriculture and can be civil structures near these gaps. In line with the international studies in this research area as a pilot scheme studied Khorramabad. In general it can be stated that decline in groundwater levels in Khorramabad plain area, increasing the effective stress in the alluvial plain water depths ranging from plain and prevent to avoid potential supply normal rainfall factors accretion phenomena Khorramabad plain island subsidence. Near the underground water, Thickness of clay and fine materials, the presence of active faults Khorramabad anticline and humanitarian intervention mechanisms developed in this area, because increased incidence of subsidence phenomenon in the area that will be output by the model is consistent with the content. پرونده مقاله