Journal of Engineering Geology

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Tunnel boring machines (TBM) are widely used in excavating urban tunnels. These kinds of machines have different types based on supporting faces and tunnel walls. One type of these machines, is the Earth Pressure Balance (EPB) type that was used in excavating the Line 1 Tunnel of Tabriz Metro. Different parameters such as geological conditions, rock mass properties, dip and machine specifications affect the efficiency of the machine. One method of predicting the efficiency of these machines is to estimate their penetration rates. In this study the value of TBM penetration rates are predicted by an artificial neural network. Predicting of this parameter is so effective for conducting in high risk regions by understanding the time of facing to these regions. The main result of this study is to forecast the penetration rate with an acceptable accuracy and to determine the effective parameters through sensitivity analysis measured by an artificial neural network.

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Marl rocks are from weak rocks which cause some problems due to high swelling and efflorescence capability, low resistance and durability in construction of engineering structures. Creation of these problems is due to inadequate recognition of engineering geology properties of these rocks. Hence, in this research for determination of the physical and mechanical parameters of marl rocks of Safa dam site, Aterberg limits, density, porosity and moisture percent, uniaxial compressive strength (UCS), direct shear, swelling and three axial compressive strength tests and X-ray diffraction (XRD) and X-ray fluorescence (XRF) analyses were performed on available samples from excavated bores. Results of experiments indicate that the type and contents of minerals and percentage of calcium carbonate in marl rocks, especially clay minerals are effective factors on engineering geology properties of these rocks

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One of the tests that is used for the characterization of soil abrasivity, is LCPC test. LCPC test device is designed for measuring the wear particles as small as pebbles (4-6.3 mm). In this study, some of the most important abrasive minerals were collected from different parts of Iran for analyzing the effect of the geological parameters on the ability of abrasive minerals. Firstly, amount of index minerals abrasivity is measured according to three standards of AFNOR P18-553, AFNOR P18-579 and AFNOR P18-560 that are the preparation of samples for testing, procedure of laboratory tests and analysis of grain size with laboratory sieves. The effect of geological parameters affecting the wear rate of the sample, including five parameters of shape, size, angularity and saturation rate of the environment, has been studied. The effectiveness of these parameters on the abrasivity of samples are studied according to NF ISO 5725 relating to usage of statistics, the accuracy of test method, the repeatability and the ability to reproduce a standard way of testing within laboratory (based on classification index X 06-041). Finally, after ensuring significant effect of these parameters on the abrasivity of minerals by help of SPSS, abrasivity rates for types of minerals that have the hardness below 7 in the Mohs hardness scale, have been predicted.

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Khorasan Razavi province is one of the areas with many chains of Qanat and Mashhad city in the center of this province has developed on areas with Qanat in the west direction. Loads caused by tall buildings and structures that built on old Qanats can make Qanats unstable and consequently Qanat collapse can lead to ground settlement. This paper deals with identifying the exact locations of Qanat chains by aerial photographs and evaluating the main factors that cause Qanat collapsing. Moreover the stability of Qanat was evaluated in numerical modeling by Plaxis software. The geotechnical data, Qanat depth, Qanat lining system and vertical load was used in modeling and after that, the extension of plastic zone around the Qanat underground tunnel was analyzed. The results of this research show that the rate of plastic zone extension and the influence of lining in Qanat stability decreases by increasing in the Qanat depth. As it is estimated while Qanat depth increases as much as one meter, it can tolerate more pressure as much as loads induced by a one-storey building.

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Kerman city and its surrounding towns in terms of morphology, consist of a flat alluvial plain of fine silt and clay materials. These sediments have very gentle slope, and constitute the city's main infrastructure. Natural soils generally are structured by passing times due to the influence of environmental factors. Geological factors in Kerman alluviums have caused fine structure after deposition. This paper studies briefly sedimentary basin Kerman, mineralogical and geotechnical properties of the sediments of these areas.semi-qualitative analysis of samples has shown that the mineral deposits in Kerman are mainly illite, chlorite, smectite and calcite. then In order to evaluate the effect of depositional environments and geological history of the engineering properties of the sediments of the Kerman city, A large number of triaxial tests on reconstituted soil moisture greater than LL and different confining pressures, consolidated drained and consolidated undrained is done . In order to evaluate the applicability of soil behavior in normal conditions and the reconstructed curves and stress - strain sensitive soils and soil structure compared with standard sensitivity and then their resistance have been investigated. The results of triaxial tests can be used to interpret the depositional environments and geological history. Comparing the curves of stress - strain in natural and reconstituted samples indicates that in many cases the behavior of intact and reconstituted soils were similar and cementation and soil structure have not been much development. Also Comparison of electron microscopy images of reconstituted and intact samples, not random arrangement of particular structure and soil compaction within the city limits have confirmed. therefore, soils of Kerman are relatively similar by the influence of depositional environments and geological history. these soils have a lot of structure and cementation and are generally compact and strengthening.

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Introduction
Determination of in situ stress-direction and magnitude are prerequisite for any oil well drilling and oil field development such as hydraulic fracturing. One of the simplest and most widely used methods is called borehole breakout analysis. Breakouts are compression fractures made in the direction of minimum horizontal in situ stress (Sh), if drilling mud pressure be lower than optimum mud pressure. Some borehole imaging logs such as FMI, FMS and UBI are appropriate tools for wellbore fracture detection. These fractures are distinguished in the logs as dark and symmetrical points (or lines) on both sides of the well and are used as an indicator for in situ stress studies. The size and shape of these fractures are strongly depend on the magnitude of the in situ stress. Therefore, many researchers suggested that by analyzing the geometric shape of the borehole breakout is an appropriate technique for estimation of in situ stress components. .... ./files/site1/files/0Extended_Abstract7.pdf
 

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Introduction
Hazardous waste (solid, liquid or contained gases) is a waste with properties that make it potentially dangerous or harmful to human health or the environment. Site selection and suitable conditions for hazardous wastes landfill is considered as the final stage of waste management that they have high sensivity. The purpose of this study is to identify prone areas to hazardous waste landfill for Chaharmahal and Bakhtiari province using geographic information systems (GIS) as an important tool for the analysis of potential sites and the Analytical Hierarchy Process (AHP) and to provide solutions to optimize the positioning is executed. Firstly, criteria and limitations of environmental, economic, social and physical were determined, then layers of the criteria in GIS were prepared. In this study, the inappropriate areas were first removed from the model, and the suitability of remaining regions as a categorize criterion considered. Categorize criteria for paired comparison using AHP as an efficient tool for determining the relative weight parameters are used to measure and rank the expert choice application imposed. Then the implement paired comparison of the relative weights of the criteria and sub-criteria and criteria for each category were determined. After calculating the net weight and normal weight, normal weight based on standard maps in the GIS environment has been classifieds. Finally, by combining maps and applying criteria FA map, the final map was extracted.
Material and methods
The purpose of this research is to identify and prioritize appropriate areas of special waste disposal using multi-criteria decision-making methods. In order to locate using the GIS, first, identifying, evaluating and selecting criteria and constraints for the construction of landfill, in order to reduce the economic, environmental, and health costs. In the multi-criteria evaluation method, criteria are the basis of decision making, so that a set of criteria is combined and combined to achieve a single combination. In this paper, a two-stage process was used to locate the landfill site. In the first stage, which is recognized as the identification stage of prohibited areas according to different criteria, the study area is divided into two appropriate and inappropriate classes that will be eliminated as prohibited areas for the construction of landfills. In the second stage, the various factors are ranked and weighted according to the relative importance and, finally, places that receive the appropriate points are introduced as areas susceptible to the dumping of special wastes. In order to obtain the digital data of the criteria in the GIS environment from the digital elevation map (DEM), the specifications of the piezometric wells information are available from the regional water organization of the province. The available data such as geological map of the province at a scale of 1: 250,000, satellite images of Landsat and map of land suitability of the province, rainfall data of the synoptic stations of the province and the data of the Environmental Protection Agency were used. In general, the following steps have been taken in the process of locating:
- Identification of effective locating factors (limitations and factors)
- Digitizing and providing the required layers of information using the GIS package
- Identify and eliminate prohibited and inappropriate areas for landfill construction
- Classification and weighting of the factors and layers of information sought
- Integration of layers and the provision of a mapped rate and talent to determine the appropriate areas.
Results and discussion
1. Set limits
In this study, in order to select suitable sites for landfill particular, the criteria and limitations were determined. The information layers for each of the criteria were provided in the GIS environment.
2. Classification and weighting criteria
In the second stage, which is the stage of weighting and rating, of 14 effective criteria were used in site selection. AHP is one of the most efficient techniques, multi-criteria decision. This method is based on comparing factors and to study various scenarios to give managers and decision makers. This technique is one of the most comprehensive system designed for decision-making with multiple criteria.
3. Editor hierarchy to locate
Hierarchical structure is a graphical representation of a real complex problem, which mainly target the problem and at the next general criteria, sub-criteria and options are the way in AHP is used to calculate points based on comparison test.
4. Shipping Weight Matrix Binary comparison and decision-making
After compiling a hierarchical structure, the next step is to evaluate the elements by comparing the test. In general, if the number of options and criteria respectively m and n are then paired comparison matrix of options for comparison matrix m × m and n × n matrix will be a couple of criteria.
5. After weighing and preparing the normal weight of the options, the normalized weights in the GIS environment were added to the criteria map and the Raster and Weighted layers of each criterion were prepared. Due to the wide area of the studied area, the size of each pixel was 50 * 50 m. Then, using the Raster Module, the Criterion Map was combined and a zoning map was prepared for the special waste disposal site.
Conclusions
In the present study, according to various criteria influencing the Hierarchical Analysis Process for prioritizing the criteria in decision making, based on the results, the talent map of the area was prepared for special waste dumping, in which according to the final score of the layers, the area was classified into four appropriate, relatively suitable, relatively inappropriate and inappropriate classes. Suitable areas were 12.64%, relatively fairly 32.47%, relatively inappropriate 30.43%, and inappropriate zones 9.58% of the area of the talent map were included.
./files/site1/files/123/5Extended_Abstract.pdf

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Introduction
The problematic collapsible soils are deposits with wind origin that constitute about 10% of the total area of ​​the earth. Several countries, including China, Russia, the United States, France, Germany, New Zealand, and Argentina have vast areas of collapsible soils. These deposits usually form a semi-stable honeycomb structure and are highly susceptible to sudden changes in the volume reduction due to becoming humid. Collapsibility and other related issues such as different subsidences, land cracks and landfalls seriously damage the infrastructures constructed on these soils.
 By the growing rate of urbanization in different parts of the world, the probability of construction on these soils and consequently water availability for these soils will increase; as a result, humidity increases and the collapse of these soils may occur. Therefore, studying the behavior of these types of soils is very important. Over the past six decades, many researchers have studied the collapse mechanism of collapsible soils due to becoming humid. Discussions on this subject are summarized in three categories: traditional methods, soil structure studies, and soil mechanics-based methods. In the present work, collapsibility and its controlling factors in the soils of Kerman city are investigated.
 
Material and methods
To determine engineering properties of Kerman deposits in this research, the geotechnical information was gathered and 50 core samples were extracted from different parts of the city. The sampling points were selected such that they could have a high overlap. X-ray diffraction (XRD) was applied to determine the mineral type and soil structures while scanning electron microscopy (SEM) was used to study grain arrangement.
Results and discussion
Geotechnical characteristics of the samples collected from Kerman plain deposits include their physical and mechanical properties. Based on the obtained results, this fine-grained sediment generally includes two CL and CL-ML groups. The mineralogy studies of Kerman city soils show that the minerals in these deposits are mainly illite, chlorite, illite-smectite, calcite, quartz, and gypsum. In order to study the collapsibility level of the soils in Kerman through the field studies, samples were taken from different parts of the city and the tests were carried out to determine the physical properties, collapsibility index, and structural studies. Through the SEM analyses, samples related to Haft Bagh area, Motahhari Town, and Pedar Town revealed an open structure and intergranular pores and thus a high level of collapsibility. On the other hand, in the majority of samples taken from the central part of the city, such as Esteghlal Street, Azadi Square, Bahmaniyar Street, and Hafez Street, the soil aggregates generally have corner-to-corner connectivity, with no specific order in their structure, and the arrangement of the particles is random and irregular. The orientation of the particles mostly shows no sharp pattern. In addition to soil particles, they have shown random and disorientated cavities with small sizes, suggesting the density and compactness of the soil indicating a low to moderate collapsibility. In some areas (e.g., Pedar Township and Motahhari Township), crystalline salt and gypsum crystals are clearly seen. It is expected that by increasing the amount of water, these salts dissolve and their effects can be observed as dissolution cavities.
 The dissolution of soluble crystals can also reduce the strength of the soil structure and ultimately lead to soil degradation. Calcite crystals are also found in some places in the form of calcite cement among the grains, sometimes as single crystals, and sometimes as lime nodules within the soils of Kerman city. Among the stated criteria in this research, Denisov, Holtz, and Hill criteria, the Russian regulations and ASTM standards were employed to assess the potential of the studied soil collapsing. Based on the criterion of the construction regulations of Russia, it was found that the deposits of the city of Kerman are mainly collapsible (L>-0.1).                     
Moreover, based on the Denisov criterion (if e/eL>1.5 the soil is non-collapsible, if it is between 0.75 and 1.5, the soil is prone to collapsing, and if it is between 0.5 and 0.75, the soil is severely collapsible), soils of Kerman are within the range of collapse-prone soils. Finally, based on the ASTM criterion, in some areas of the city like Motahhari Town, Pedar Town, and Haft bagh, soils show a high collapsibility. In comparison, in the central parts of the city, the values of this criterion vary between 0.15 and 11, suggesting the presence of soils with a moderate collapsibility. Comparing the results obtained using these criteria it is seen that areas with a collapsible behavior are relatively similar collapsibility results are obtained.
Conclusion
Based on the achieved results, fine-grained sediments of Kerman city are mainly composed of CL and CL-ML groups. Mineralogy results indicate that the minerals in these deposits are mainly illite, chlorite, illite-smectite, calcite, quartz, and gypsum. SEM results for the central part of Kerman city confirm the compressed and densely compact form of soil particles. The results obtained, using the construction regulations of Russia show that the soils in the study area are collapsible. According to the Denisov criterion, they were found to be prone to collapse. Finally, based on the ASTM results for the central parts of the city, soils exhibit a low to moderate collapsibility. However, in some areas of the city, such as Motahhari and Haft bagh, soils show a complete collapsibility behavior../files/site1/files/131/1Extended_Abstract.pdf
 

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Introduction
Mashhad city, the second largest metropolis of Iran, is located in an arid and semi-arid region. Overexploitation of groundwater in Mashhad plain has caused up to 22.5-meter drop in the groundwater level from 1984 to 2013. The groundwater depletion in the unconsolidated aquifer has resulted in subsidence and cracks on the land surface. To determine the land subsidence rate map and the reasons for hot spot subsidence, the latest Envisat images of the ESA Space Agency's Archive for Mashhad plain were used. leveling and GPS data were combined with the radar interferometry results and the annual subsidence rate maps with high precision were obtained. Finally, the geology and soil texture maps of study area are compared to the land subsidence map.
Methods and results
To assess the land subsidence in Mashhad plain three methods of leveling, GPS and Insar are used. Leveling data are available in three profile of of Mashhad-Quchan (BCBD), Mashhad-Kalat (BDBE) and Mashhad-Sarakhs (BEBN) in two time interval of 1994-2003. The highest rates of subsidence in the BCBD, BDBE and BEBN lines are 7, 3.5 and 8.1 cm/year, respectively. Six permanent GPS stations have been installed in Mashhad plain, among them, NFRD, GOLM and TOUS have recorded the land subsidence, with the highest annual rate of 21.2 cm/year at TOUS Station. The third method applied to assess the history of land subsidence was InSAR radar interferometry which provided the extent and pattern of subsidence in all of the study area. For this, 23 images of the Envisat ASAR are processed during the 05/24/2010 to 06/30/2003 time period. The highest subsidence rate estimated by this method was 32 cm/year in the northwest of Mashhad. In general, two subsidence bowls, in the northwest and south east of Mashhad city are identified. Fig. 1 shows the annual subsidence rate map in Mashhad plain. Using the root-mean-square error (RMSE), the accuracy of the InSAR method was verified with GPS and leveling data.
Discussion
The rate and distribution of land subsidence in Mashhad plain are affected by geological factors such as soil texture, deposit thickness, geological structures and groundwater drawdown. The geological and geophysical studies and exploratory drilling results in the Mashhad Plain indicate that the bedrock morphology is very rough. The bedrock outcrops in some places while in some other places covered by more than 300 meters alluvial deposits. Generally, by distance from the mountain, alluvium thickness and as a result the likelihood of subsidence would be increased. Mashhad plain is surrounded by the active and quaternary faults in the north and south edges. In the north of Mashhad plain Marly bedrock is uplifted by Tous fault and outcropped in the north of fault. In the south of Mashhad two normal faults have resulted to the increase of alluvium thickness in south and central of Mashhad plain. The change of river pathway also let to deposition of a sequence of the fine-grained and coarse-grained soils in central of plain between Toos and southern branch of South Mashhad fault (F2).
used to draw the cross section
In order to evaluate the subsurface conditions and its effect on the land subsidence, the soil texture are studied using the deep water wells and piezometers log (Figure 2). Fig. 3 shows the longitudinal section (northwest to southeast) of the area. As it can be observed, the soil texture includes of alternation of fine and coarse grains layers (Figs. 4). In this condition, sandy soils help to shortening the drain path of clayey layers and leads to acceleration of the consolidation. The average rate of annual subsidence in the area is 14 cm for one meter of drop in the groundwater level.
Nowadays, in the urban area, due to the urban sewage waters, there is a rising of groundwater level.  Therefore, no land subsidence has occurred in the central parts of the city. It is expected by completion of urban sewage network about 62 million cubic meters of sewage water will be eliminated from the aquifer recharge, which will cause a notable drop in the groundwater level and prominent land subsidence in specific area of the city. Considering the geological conditions and the operation of the existing faults, it is expected that in the case of groundwater drop, no significant subsidence will occur in south of the F2 fault, due to the decrease in the alluvium thickness and to the coarse texture of the soil. But in the northern and northeastern parts of the city, which are located between F2 and the Tous faults, high rate of land subsidence is expected.
Figure 4: The cross section of soil texture and the annual average rate of land subsidence and groundwater level drop
Conclusions
Using the radar interferometry processing, the highest annual rate of subsidence in Mashhad plain is about 32 cm/year. Land subsidence in Mashhad plain has an increasing trend and the geological conditions have a critical role in the subsidence rate and its pattern. Generally, soil texture near the mountain area in South is coarse and grain size decreases toward the center of the plain. But because the outcrop of Marly formation in the north slopes, soil texture is mainly fine grains. In the center of Mashhad plain soil texture constituted of fine and coarse grains which are converted together as inter fingering facieses, which have a critical role in decreasing of the consolidation time and increasing the land subsidence rate. It is predicted by complimenting of the urban wastewater network, the groundwater level will be dropped in the city area and the northwest and southeast subsidence ellipsoids which already can be seen will be connected together. Therefore, the area between F2 and Toos faults, will be shown the highest rate of subsidence, due to high thickness and fine-grained soil texture../files/site1/files/133/5Extended_Abstracts.pdf