Showing 4 results for S. M. A. Zomorodian
S. M. A. Zomorodian, M. R. Bagheri Sabzevari,
Volume 9, Issue 4 (winter 2006)
Abstract
The vertical pipe intake is an economical structure relative to the other alternatives. VPI usually installed near the water surface and prevents from the coarse sediment entrance to the system. The strong vortex in VPI entrance is a major problem which may reduce the system efficiency. Recognizing the vortex affected parameters, helping engineers to design anti vortex structures. In this study an experimental model is built to study the effect of tangential velocity, flow direction at approach channel outlet on the discharge coefficient of vertical pipe intake. By dimensional analysis it is indicated that the vortex in VPI could be defined by the dimensionless numbers (Reynolds, Weber, Froude, Circulation and Submergence). The relationship between the Froude, Circulation and Submergence numbers are presented. By using this relation one can determine the Submergence number and then calculate the discharge coefficient of vertical pipe intake.
S. M. A. Zomorodian, M. Khoshkoo,
Volume 16, Issue 61 (fall 2012)
Abstract
Internal erosion is the second major reason for earth dam's failure after overtopping. One of the effective factors in internal erosion in earth dams is the clay minerals used in dams as well as the effects of compaction efforts on soil in sample preparation. In this research, internal erosion and the effect of clay minerals and compaction effort on internal erosion were investigated. For this purpose, Kaolin clay and Na Montmorillonite (Bentonite) separately and with different percentages of mixture were used to investigate the effect of different percentages of Bentonite on internal erosion. Two hammers of standard compaction and modified compaction test were also used to investigate different compaction efforts in internal erosion. The results showed that as compaction effort increased in constant water content, erodibility also increased to about 3%. In addition, it is found that erodibility of kaolin clay is more than bentonite, which reaches 65%. Finally, by adding 12% bentonite to kaolinite, erodibility decreased to a great extent.
S. M. A. Zomorodian, H. Chochi,
Volume 16, Issue 62 (Winte - 2013 2013)
Abstract
Excess pore water pressure in clay core dams during construction and primary filling reservoir (first impounding) causes initiation and progression of hydraulic fracture. In this research, the instrumentation data during construction and first filling reservoir (first impounding) was analyzed. It measured internal deformations, pore water pressures and total vertical stresses and compared with the analysis results in Masjed-e-Soleiman dam. To do this analysis, GEOSTUDIO 2004 V. 6.02 software was used. The staged construction of the dam was the model in the form of 2D coupled consolidation. The Non-linear elastic model for the core material and Linear Elastic model for other zones were incorporated into the models. For exact assessment and to obtain correct parameters of the constitutive model, the triaxial tests were performed on the core material of Masjed-e-Soleiman Dam and acceptable results were obtained.
P. Bagheri , S. M. A. Zomorodian,
Volume 17, Issue 63 (Spring 2013)
Abstract
Hydraulic conductivity is an important parameter in the design of geotechnical structures such as earth dam, floor construction, retaining walls and environmental structures. In unsaturated soils, hydraulic conductivity is a function of moisture content and soil water suction i.e. soil moisture characteristic curve. In this study, the values of unsaturated hydraulic conductivity in two soil types (Ramjerdi and Molasadra core dam series) at 5 different compactions using Gardner method were measured. Then, the unsaturated hydraulic conductivity was estimated by different models using the soil moisture characteristic curve and was compared with measured values. The results showed that Fredlund and Xing models predict the soil moisture characteristic curves more accurately compared with van Genuchten model. For Ramjerdi soil series and up to nearly 0.25 volumetric water content, (VGM) and (FM) models indicated a good estimation for unsaturated soil conductivity. Also, for Molasadra core dam none of the models resulted in acceptable estimations for unsaturated hydraulic conductivity.
