M. Majdi; A. Uromiehi; M. R. Nikudel
Abstract
In this study, the effect of nanokaolinite particles on geotechnical properties of clayey soils is investigated. The mechanical method of Planetary Ball Mill was used for production of nanoparticles. For this, initial kaolinite powders was milled in Planetary Ball Mill for 10 hours with speed of 500 ...
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In this study, the effect of nanokaolinite particles on geotechnical properties of clayey soils is investigated. The mechanical method of Planetary Ball Mill was used for production of nanoparticles. For this, initial kaolinite powders was milled in Planetary Ball Mill for 10 hours with speed of 500 Rpm of machine. Output powder was in nanometer scale that images produced from FESEM verified this. Then, nanoparticles were mixed with clayey soil (CL) in different weight ratio of dry soil and change percentage of geotechnical properties of treated soils was investigated by compaction, direct shear and cassagrande tests and optimum percentage of added nanokaolinite was determined. Results showed that LL and PL of soil increased while percentage of added nanoparticles increased but since increasing of PL is larger than LL, thus PI is decreased that it is favour for geotechnical engineering for construction. Also with attention to results of compaction tests, density of clayey soil was increased with adding of nanoparticles to an optimum quantity and after it decreased. It is determined from direct shear tests that cohesion of clayey soils increased with adding of nanoparticles to optimum quantity and after it is changeless approximately. Results of XRD and XRF tests showed that chemical integition of nanoparticles produced from planetary ball mill is similar to initial powder and not change.
M Kamani; A Uromeihy; M Joorabchi
Abstract
Roads are of linear engineering projects passing various rock units and geological conditions, so it is necessary to engage the engineering geological studies along the way. The studies continue until the end of the construction and operation. In the route selection process, large volumes of data and ...
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Roads are of linear engineering projects passing various rock units and geological conditions, so it is necessary to engage the engineering geological studies along the way. The studies continue until the end of the construction and operation. In the route selection process, large volumes of data and different track conditions are facing. To perform this manually is time consuming and not accurate enough. This study examines the status of engineering geology freeway route Qazvin - Rasht in Roudbar discussed in this context, the factors affecting engineering geology route selection and construction of the freeway, using the Analytical Hierarchy Process (AHP) and Expert Choice software to give weight of these factors, according to their suitability for the construction of freeways, and then layers weighted overlay in GIS software and the final map has been prepared. The final map shows the quality of route engineering geological conditions, which is provided for both surface and subsurface (tunnels) with the least error. Since the procedure for engineering geological survey route is a new method, it requires further investigation and to test in other places in order to be much more modified and corrected. On the other hand, this model can be used for other engineering geological investigations due to high flexibility of this model.
M Kianpour; M Sayari; A Uromeihy; M.R Nikudel
Abstract
Shear strength is one of the most important properties of mudrocks and shales in rock engineering and engineering geology. Because of the difficulty to obtain undisturbed samples of shales as required for determination of shear strength parameters, it is also the most difficult to evaluate. This research ...
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Shear strength is one of the most important properties of mudrocks and shales in rock engineering and engineering geology. Because of the difficulty to obtain undisturbed samples of shales as required for determination of shear strength parameters, it is also the most difficult to evaluate. This research investigated properties that can be used to predict the shear strength parameters of Shemshak formation shales. Thirty samples of shales from various depths were collected from boreholes in Shemshak formation in the site of Siahbishe pumped storage powerhouse. Shear strength parameters (c and ϕ), tensile strength (TS), quartz percent (Qz %), porosity (n) and density (ρ) were determined in lab for each sample. Data were analyzed statistically and with fuzzy inference system to determine the relationships between shear strength parameters with other properties. Results show that cohesion and friction angle of shales can be meaningfully predicted from a few engineering properties by fuzzy inference system. The adjusted R2 values between measured and predicted values for cohesion and friction angle are 0.95 and 0.84 respectively. Also the variation of regression coefficient (R2), performance indices (VAF) and root mean square error (RMSE) with were calculated as for the shear strength parameters, obtained from the multiple regression modeland the fuzzyinference system, revealed that the prediction performance and accuracy of the fuzzy models are high and multiple regression equations not have performance in prediction of shear strength parameters of shales.
