Document Type : Original Research Paper

Authors

1 Research Institute for Earth Sciences, Geological Survey of Iran, Tehran, Iran

2 Soil Mechanics Laboratory of the Ministry of Road and Transportation, Tehran, Iran

Abstract

The Tehran city, capital of Iran is located on young alluvium deposits which mostly cover due to rapid urban development. This urban development without proper geotechnical and geological assessment may cause great engineering and economic problems. Survey of geotechnical problems are one of the most important issue that consider for building important structures. Most of constructions are based on the ground. Hence the Examination and recognition of physical and mechanical properties of soil layers are so necessary. Present research aims to determine stability parameters, plat bearing and amount of foundation settlement in East and South-Eastern of Tehran in Ghalemorghi area.  For this specific  zones have been identified, among them, first, second and third zones have middle (2<qa<3), good (3<qa<4) and very good (4<qa<6) stability (bearing conditions).  4th and 5th zones show low (1<qa<2) and middle (2<qa<3) bearing condition. The 6th area has low (1<qa<2) and very low (0<qa<1) stability conditions. In a general view soil density decrease from north to south due to gradual change of sand and gravel deposits to clay deposit and with depth it increase. The amount of immediate settlement also decreases with depth. (Rezaei, Adib & Eivazi, 2007).
 Comparison between old and new researches show that in new researches, amount of plat bearing is more  and amount of settlement less than old researches in surface layers (0-5 m), but there arent any important changes in amount of plat bearing and settlement in deeper layers. We think increase in amount of plate bearing, and decrease in amount of settlement in surface layers have been caused by increasing and accumulation of constructions, and also increase of traffic in duration years. The further studies show that effect of loading decrease with depth. Amount of stability and settlement in each zone have important role to design and select the kind of foundation and lay out depth. 

Keywords

References
 
Bowelse, j., 1988- "foundation analysis and design"
Budhu M., 1989- Soil Mechanic and Foundation John Wiley Sons INC.
Das B.M., 1994 -  Advanced soil mechanics- (University of Tehran press).
Memarian, H., 1998- “Engineering Geological Considerations For site Selection of New Cities in Iran.
Meyerhof, G.G., 1963- Some recent research on the bearing capacity of foundations. Canadian Geothecnical journal, vol. 1, 16-26.