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Volume 1, Issue 2 (11-2003)

(Paper pages 133-156) Zagros active fold-thrust belt lies on the northern margin of the Arabian continental crust it is a young fold-thrust mountain belt currently shortening, thickening and uplifting as a result of the collision of the Arabian and Iranian plates. Rethickening of crust during collisional orogenies could have been carried out by reversal of fault motion along the Mesozoic normal faults (Jackson 1980, Jackson and Fitch 1981, Berberian and king 1981, Jackson etal. 1981) This study constitutes contribution towards an estimation Rate of uplifting along the High Zagros Fault and fault patterns in the southern margin of High Zagros fold-thrust belt. The High Zagros deep-seated fault is located between High Zagros thrust belt and Zagros Simply Folded belt in the southern margin of the High Zagros belt. (Berberian , 1995). The Farsoon – Baghe Hiran –Goushki fault is a part of High Zaros Fault (H.Z.F) system and is located northeast of Lordegan city in Chaharmahal State.In this region on the basis of field geology a geological map (scale :1: 50/000) is prepared. For the recognation of fault pattern, enechelon faults of H.Z.F. and estimation rate of uplifting along the H.Z.F three structural sections have been drawn. Correlation between geological structures, fault patterns in High Zagros Fault system ‘stratigraphic profiles’ enechelon. faults of H.Z.F and paleogeographic data give us an insight to many conclusions.There are many footwall-vergent shortcut thrust, hanging wall by pass thrust and hanging wall vergent back thrust developed with High Zagros fault. Footwall shortcut thrusts ,hanging wall by pass thrust and backthrusts are common features of Inversion tectonic Settings. In this region, the fault pattern and stratigraphic curves indicate inversion tectonic in pre-existing extensional normal faults. -The minimum throw (uplifting) of a fault depends on the thickness of formations that is omitted along the fault and with respect to stratigraphic units thickness and geological cross sections, the minimum rate of uplifting along the H.Z.F. is about 2.05 0.1 mm/year

Volume 3, Issue 1 (11-2009)

(Paper pages 591-614)
The Zydoun plain experiences semi-arid climatic conditionو and though groundwater quality is not commonly acceptable with respect to drinking, it is used for irrigation. The water withdrawal of water and its increasing trend would probably put the study area into critical condition to meet demand. The main sources of water supply in the region are Zydoun aquifer and Zoreh River. The better quality of groundwater in the extreme southern part of the plain and lower exploitation expenses are the reasons why farmers prefer to use groundwater rather than river water. As a result of over- exploitation from the Zydoun aquifer in the last years water table has been declined. In order to impede critical situation in the area, a detailed study regarding management of groundwater including physiography, meteoro-logy, hydrology, hydrogeology, hydrochemistry and geomor-phology were undertaken. Based on these investigations, a number of ephemeral streams in the southern part of the plain were recognized to be suitable in term of water quantity and quality to secure a part of water demand of the area. One of the optimum methods for long-term use of these water resources is injection of water into ground and withdrawal in required time. to this end, the collected data, were put together and it was found that the most suitable method of artificial recharge was channel modification. At the end, considering consideration, morphological, permeability condition and water demands in the southern part of the Zydoun plain, eleven sites for execution of water resources management were suggested which would annually augment aquifer storage by over one MCM.
R Ajalloeian, M Mohammadi,
Volume 5, Issue 1 (9-2011)

(Paper pages 1059-1076)
Physical and mechanical properties of intact rocks are very important in civil engineering works that interact with rock such as underground structures, dams,foundations on rock, and rock slopes. Therefore geomechanical parameters such as compression strength and deformation modulus of rock can have fundamental importance in the different stages of design. Determination of these parameters is time consuming and costly. Since Asmary formation has broad outcrop in the west and southwest of Iran and many large projects are located in this formation, therefore it is a requirement to accomplish the present research. This paper is dealing to analyzing data from laboratory of two major projects of the Khersan 1 and 2 dam sites. In this regard, the physical, mechanical, dynamic and durability properties of intact rock and geology controlling agents of these changes has been evaluated and analyzed. Finally, new experimental relations between different parameters have been presented.
Ali Ghanbari, Mohsen Mojezi, Meysam Fadaee,
Volume 6, Issue 2 (4-2013)

Construction of asphaltic core dams is a relatively novel method especially in Iran. Iran is located in a region with high seismicity risk. Therefore, many researchers have focused on the behavior of such types of dams under earthquake loading. In this research, the behavior of asphaltic core rockfill dams (ACRD) has been studied under earthquake loading using nonlinear dynamic analysis method and a new method is presented to assess seismic stability of these types of dams in earthquake conditions. Based on nonlinear dynamic analysis, the current study attempts to provide an appropriate criterion for predicting the behavior of earth and rockfill dams considering real behavior of materials together with actual records of earthquake loading. In this method, the maximum acceleration of the earthquake record (PGA) increases until instability conditions. Finally, a new criterion is presented for evaluating seismic safety of ACRDs via demonstrating curves of the crest's permanent settlement and maximum shear strain against maximum earthquake acceleration. Results of the proposed criteria can assist designers of asphaltic core dams to predict dam stability during earthquake event
Reza Ghaderi -Meybodi, Gh Khanlari,
Volume 6, Issue 2 (4-2013)

One of the geotechnical hazards in the tunnels under high overburden and high in situ stresses is the phenomenon of rock burst. Rock burst is a typical geologic phenomenon caused by excavation in rock masses. In this phenomenon, because of stress released and explosion in rock masses, they are broken as large and small pieces and are distributed, so that leads to damage of peoples or equipments. Therefore, familiar with this phenomenon and its mechanism of occurrence, is need to analyze this issue. The second part of water supply Karaj-Tehran tunnel with a length of 14 km and about 4.5 m diameter is located in Tehran province. Rock burst analysis has been carried out in the tunnel from kilometer 6 to 9.5 that is critical section because of high overburden (up to 800 m) and presence of faults and crushed zones. In this paper, for predicting rock burst in the critical section of second part of Karaj-Tehran tunnel, four criteria including, Strain energy, Rock brittleness, Seismic energy and Tangential stress criterion are used. Analysis results show that units with high overburden have high possibility of rock burst. 
S. M. Fatemiaghda, V. Bagheri, M Mahdavifar,
Volume 7, Issue 1 (8-2013)

In this research, one of the new methods for seismic landslides hazard zonation (CAMEL) to predict the behavior of these types of landslides have been discussed.  It is also tried to eveluate this method with the proposed Mahdavifar method.  For achieving this result, the influence of  Sarein earthquake (1997), have been selected as a case study. In order to apply seismic hazard zonation, the methodology of Computing with Words (CW), an approach using fuzzy logic systems in which words are used in place of numbers for computing and reasoning is employed. First, the required information which includes disturbance distance, ground strength class, moisture content, shake intensity, slope angle, slope height, soil depth, terrain roughness, and vegetation have been collected using air photos, Landsat Satellite images, geological and topographic maps, and site investigation of the studied region. The data is digitized and weighted using Geological Information System (GIS). At the next step, the hazard rate and areal concentrations with respect to landslide types are calculated using CAMEL program and then, landslides hazard map produced by the above mentioned method is compared with landslides occurred as a result of Sarein earthquake. Finally, for evaluating on prediction of the earthquake-induced landslides, empirical comparison have been done between CAMEL and Mahdavifar methods.
, Greza Khanlari, M Heidari, Yazdan Mohebi, Reza Babazadeh,
Volume 7, Issue 2 (3-2014)

Awareness of orphological features of rivers is necessary for recognition of river behavior and optimum application of rivers. Overall catchment physiografy have important role for determination factors such as floods, erodible and sediment mutagenicity. In this study in order to understand the behavior of Gamasiab River in the east of Kermanshah province, geomorphologic features of this river has been considered. Study of engineering geomorphologic properties is done by using existing data from previous studies, site visit and field perceptions, study of geology and topography maps. Physiographic properties of catchment, channels morphologic properties and geology conditions in this region have been studied. In this research, several parameters such as average width, environment, area, hydrogeologic coefficient, catchment form, maximum, minimum and mean high, and longitudinal slope has calculated. Also status of drainage density of this river has been investigated and time to focus calculated. Finally this river review and classified according to various classifications for rivers
Majid Dashti Barmaki, Mohsen Rezaei, Amir Saberi Nasr,
Volume 8, Issue 2 (11-2014)

This paper has evaluated the groundwater quality index of Lenjanat aquifer. Water quality index as a unique index is presented to describe overall water quality conditions using multiple water quality variables. Physical and chemical data of 66 water samples were used in this study. The results have been obtained by Comparing the qualitative features with the World Health Organization (WHO) standard and Industrial Research of Iran (ISIRI) standards. In calculating GQI, 7 parameters, including calcium (Ca), magnesium (Mg), sodium (Na), chlorine (Cl), sulfate (SO4), total dissolved solids (TDS) and nitrate (NO3) have been used. Groundwater quality index shows the medium to relatively high groundwater quality in the study area. Minimum and maximum value of the index is calculated as respectively 55 and 93. Land use map shows that along the Zayanderood River and around the location of rice paddies, water quality reaches to the lowest quantity. Optimum index factor technique allows the selection of the best combination of parameters dictating the variability of groundwater quality.
Arash Shareghi, M Amelmelsak, A Sohrabi Bidar,
Volume 8, Issue 4 (3-2015)

Evaluation of strong ground motion up beneath the construction is important in both geotechnical engineering (site effect) and earthquake engineering aspects (analysis of earth behavior). The common methods of microzonation in geotechnical engineering are based on one dimensional dynamic analysis, in which ground surface is assumed to be horizontal. However in many cases, because of variety of topography conditions, recorded responses are different on the top of hills and their corners. In this study, FLAC 2D software, as finite difference software, is used to analysis the trapezoidal hill with different shape ratios. These topography models are analyzed by far field earthquake records, and their dimensionless amplification ratios are compared with the obtained results of one dimensional analysis. Assessment of these two analyses methods in some points on the topography and around it, demonstrated considerable differences that show the necessity of two dimensional analysis in earthquake geotechnical engineering.
Davood Fereidooni, Mohammad Hossein Ghobadi,
Volume 9, Issue 2 (9-2015)

In order to assess mineralogical composition influence on durability and strength of rocks, four samples of hornfelsic rocks were selected from southern and western parts of the city of Hamedan, west of Iran. These rock samples were subjected to mineralogical, physical and mechanical tests in the laboratory. Also, they were evaluated in 15 cycles of slake-durability testing in different pH of sulfuric acid solutions and XRD analysis. Based on the results, the type and amount of minerals, their density and hardness had an influence on the uniaxial compressive strength and the slake durability index of tested rocks. That means, presence of non-dissolved minerals such as graphite in studied rocks, decreases Unconfined Compressing Strength (UCS) but increases the slake durability index. The results of slake-durability test indicated that weight loss of the samples at initial cycles was found to be higher than the end cycles. Also, in these samples, initial minerals in the fresh samples were not exchanged by secondary minerals such as clay minerals. Therefore Hamedan hornfelsic rocks are approximately resistant when were put under accelerated chemical weathering and degradation in the laboratory and natural chemical weathering.
Samaneh Poormohammadi, M.r. Ekhtesasi, M.h. Rahimian,
Volume 9, Issue 4 (3-2016)

Mountains are usually formation origin of their neighbor land surface features such as hillsides and plains. some problems and errors may occur in application of RS technique for generation of geology maps and in separation of these units from other similar units. The main objective of this study is to integrate RS and geomorphology approaches for identification of different geomorphology units and finally separation of debris lime stones from massive lime stones in Bahadoran region, Yazd province. For this purpose, a Landsat ETM+ image was acquired together with band ratios, principal component analysis and factor analysis approaches to generate lime stone distribution map. Results of this study show that (integration of RS and geomorphology sciences) can better generate the lime stone distribution map compared with the first one
Sahar Rezaian, Seyed Ali Jozi, Sadaf Ataee,
Volume 10, Issue 2 (11-2016)

Objective of the present research is to identify, analyze, and assess risk of Paveroud Dam during construction phase. Following collection and analysis of the information related to environmental conditions of the area of study and technical specifications of dam construction, a list of probable risk factors was prepared in the form of a questionnaire, and for verification, the questionnaires were provided to a group of specialists consisting of elites and professors specialized at the disciplines relevant to environment and civil engineering. Number of questionnaires was determined based on Cochran’s formula. In the first step, the expert group in the research was asked to score in Likert scale format so as to analyze the acquired responses and the risks present in the region. Having analyzed the scores using the findings of PHA method, TOPSIS technique was applied to prioritize the identified risks of Paveroud Dam. The results indicated that erosion had the highest priority among 36 risk factors. After prioritization among the risk factors, risk was also assessed using RAM-D technique in which “impact on Sorkhabad Protected Zone with 9 scores, “erosion” with 6 scores, and “work at high elevation” with 3 scores were recognized as three major risks of Paveroud Dam. In order to mitigate the effects of dam risks during construction phase, environmental management planning is crucial, and for this purpose, risk mitigation choices were recommended at the end aimed at coping with the identified risks.

Abbas Zeighmi, ,
Volume 10, Issue 2 (11-2016)

The Sharbyan river is located in the Sharbyan village, Sarab, East Azarbaijan province. This river alluvials are supplied from rock units belonging to Oligo-miocene and Miocene, including conglomerate, sandy lime, limestone, marl and shale. These deposits are used as raw materials of producing hot asphalt in two asphalt plants that have been built in the vicinity of this river, and the produced asphalt is used mainly in the neighbor provinces that have rather cold climate. Combined analysis of the sediments indicate high level of silica, around 60 percent, for which  the prepared asphalt  is prone to stripping phenomenon in the cold seasons. During this process, the moisture penetration in aggregates and asphalt mixtures, causes weakening bitumen-asphalt materials bounding and finally asphalt demolition.  The role of sediments and its impact on the quality of asphalt has not been studied in this area, therefore, the solutions for dealing with this phenomenon is also examined and presented. This study is based on the conventional sedimentology methods, different standards of ASTM, AASHTO and Ministry of Roads and Urban Development guidelines. In this study, the combined effects of hydrated lime (lime filler) and natural filter materials with different proportions was used to deal with the stripping phenomenon, and  the parameters of strength, softness, indirect tensile strength, asphalt quality and durability criteria, have been appraised. The results show that these parameters are improved using additives in various proportions and the produced asphalt quality and durability is better. The results illustrate, when the lime is used in its maximum ratio of 3%, stripping score is 1 and is disappeared by other parameters improvement

Mh Ghobadi, M Kapelehe ,
Volume 10, Issue 4 (5-2017)

Durability is a significant parameter in engineering geology and it shows the extent of the degradability of rocks as the result of mechanical and chemical breakdowns. This phenomenon is closely linked to the composition, porosity and texture of rocks. To understand the relationship between the chemical composition of rocks and their durability the mineralogical properties of the rocks along with durability tests under both acidic and alkaline pH environments were determined. Five samples of limestone and three samples of marl were analyzed. The results revealed that rocks containing high levels of CaCo3 were affected in the acidic conditions while rocks containing high levels of SiO2 were not affected by variance in the pH of the environment. These second groups of rocks were more dependent on the texture of their constituent minerals.
A Erfani , A Ghanbari , A Massumi ,
Volume 10, Issue 5 (7-2016)

Previous earthquakes have shown that topographic irregularities have significant impacts on the site seismic response and increasing structural damage by amplifying seismic responses. Studies on seismic behavior of slope topographic have shown that dynamic response of free field and soil-structure system is severely on the influence of topography shape and soil properties. Angle and height of slope, frequency of excitation, nonlinear behavior of soil and depth of bedrock are other parameters that affect on the response of the entire system. Furthermore the studies have shown that presence of structure adjacent to slope is very effective on variation of seismic behavior pattern of this topography but these studies are very limited. In this study the effect of existing structure adjacent to slope to seismic behavior pattern of slope topography have been investigated. The parameters that have studied in this article comprise slope angle and frequency content of excitation. The results show that the presence of structure adjacent to the slope, causes an increase to the response of free field and transmitting maximum response to distance away from structure position.

Nima Headarzadeh, Tania Taslimi,
Volume 11, Issue 4 (5-2018)

One of the most important 1-ring aromatic organic pollutants is phenol and its related compounds. These compounds are classified as hazardous wastes base on U.S.EPA primary contaminates list. The phenolic compounds are very poisonous and these are harmful for human health and also for other biota.
To control the movement of such hazardous organic waste in a contaminated soil, solidification/stabilization (S/S) process can be an effective alternative.  Due to the negative impact of organic compounds on the cement hydration, the cement-based S/S may be not effective for controlling the movement of such pollutants. To avoid these effects, using some additives during solidification period has been recommended. One of the proposed of such compounds is organophilic clay that is the modified montmorillonite by quaternary ammonium salts (QAS). There are several researches to evaluate the organophilic clay effect on adsorption and stabilization of organic compounds during S/S process. The effectivity of S/S process can be examined by several tests such as leaching test, durability, unconfined compressive strength (UCS), etc.
In this study, efficiency of ordinary and organophilic clay was evaluated in the solidification and stabilization process based on unconfined compressive strength of a phenol-contaminated soil.
Material and methods
In this study, an artificially phenol contaminated sand was considered to evaluate the effectivity of the white cement based S/S process by using two different additives of ordinary and organophilic clay.
The contaminated sand contains 2000 ppm of phenol. S/S process was conducted on 14 samples with different amounts of white cement (15 and 30 wt%) as binder and ordinary/organophilic clay (0, 8, 15, and 30 wt % for each of them) as the additives. Two zero percent additive samples are considered as control samples.
All samples were cured for 28 days and then UCS test was conducted for all of them.
Results and discussion
Unconfined compressive strength of all examined samples were ranged from 2226 to 6999 KPa. In the samples with equal amount of cement, th higher UCS values can be observed in blank samples (without any additives and phenol). By adding phenol in the examined sand, UCS of the solidified sample reduces 3 -3.5%.Moreover, results showed that UCS was reduced by increasing the amount of clays. The reduction of the samples containing organophilic clay was higher than samples containing ordinary clay. Unconfined compressive strength values of all samples met the minimum standards indicated by France, Netherlands, Britain and America for disposal in a sanitary landfill. The sample with 30% white cement and 8% bentonite was the maximum amount of UCS (4856 KPa) and the sample with 15% white cement and 30% organophilic clay was the minimum one (2226 KPa). In this study, the average cost of organophilic clay-based solidified samples was 2.3 to 2.8 times more than the average cost of the bentonite-based solidified samples.
In this study, the strength of the cement-based solidified samples contaminated by phenol was investigated. The summary of the findings of the research is as follows:
1. By adding the phenol to pure sand, the UCS of the samples can be reduced 3-3.5 %.
2. Addition of organophilic clay reduces the UCS of the samples more than the ordinary clay (bentonite) in the same amount.
3. All samples met the recommended UCS level for the S/S process. The minimum UCS level is for the sample with 15% of cement and 30% of organophilic clay.
The cost of S/S process is between 23 and 650 $/ton of contaminated soil depending on the amount of used additives and binder. The samples containing organophilic clay has a higher cost than the similar sample containing ordinary clay.
4. To evaluate the S/S process effectivity, a leaching test of phenol (such as TCLP) is recommended  ./files/site1/files/0Extended_Abstract2.pdf
, , , ,
Volume 12, Issue 1 (8-2018)

 IExtended Abstract
The Iranian plateau is situated in the Alpine-Himalayan orogeny between the Eurasian plate in the north and the Arabian plate in the south. It is being shortened by the northward movement of the Arabian plate, which causes the most parts of Iran to be active and dynamic in terms of tectonic movements. The recent tectonic activity in the southern edge of central Alborz causes both development and deformation of the tectonically active landforms. Seismic records indicate a high frequency of earthquakes of relatively small magnitude (<4) and infrequent large earthquakes (>5.1) in the Alborz. The studied area is located in the southern central Alborz and at the edge of northwestern central Iran between seismic faults of Ipak (with approximately E-W trend) and Avaj (with NW-SE trend) that includes significant earthquakes. Generally, the dominant tectonic structures of the study area involve thrust faults. The Ipak fault is one of the major fault systems in the area, located about 120 km west of Tehran, and caused the 1962 Buin Zahra earthquake of Ms 7.2 (Mw 7.0). The earthquake was associated with 95 km surface rupture along the Ipak reverse fault with average throw of 140 cm and left-lateral displacement of 60 cm. This investigation has evaluated the active tectonics and the acceleration zoning of the region in order to analyze and measure the recent tectonic activities.
Material and methods
To assess the acceleration zoning of this region, seismic data, Kijko software, PSHA software and reduction equations were used; consequently, minimum and maximum acceleration for useful life of 75-year and 475-year building were estimated. In order to assess the relative tectonic activity through the study area, sub-basins and stream network were extracted by using Arc Hydro Tools software based on the DEM and in turn, 134 sub-basins have been resulted. The six geomorphologic indices were used as follow: Stream length–gradient index (SL), mountain front Sinuosity (Smf), Ratio of valley floor width to valley height (Vf), Asymmetric factor (Af), Hypsometric integral (Hi) and drainage Basin shape (Bs). Eventually, after calculating the relative tectonic activity index (Iat), the studied area was classified into four tectonic activity classes in ArcGIS10.1 as very high, high, medium and low.
Stream Length–Gradient Index (SL): The SL index indicates an equation between erosive processing as streams and rivers flow and active tectonics. The SL is defined by Eq. (1) 
SL= (∆H/∆Lr) Lsc                                        (1)
where ΔH is change in altitude, ΔLr is the length of a reach, and Lsc is the horizontal length from the watershed divide to midpoint of the reach. The SL index can be used to evaluate relative tectonic activity.  The quantities of the SL index were computed along the streams for all sub-basins.
Index of Mountain Front Sinuosity (Smf):  Index of mountain front sinuosity is defined by Equation (2). 
Smf = Lmf ⁄ Ls                                             (2)
where Lmf is the length of the mountain front along the foot of the mountain in which a change in slope from the mountain to the piedmont occurs; and Ls is the straight line length of the mountain front. Smf represents a balance between erosive processes tending to erode a mountain front, making it more sinuous through streams that cut laterally and into the front and active vertical tectonics that tends to produce straight mountain fronts, often coincidental with active faults or folds.
Ratio of Valley Floor Width to Valley Height (Vf): Vf is defined as the ratio of the width of the valley floor to its average height and is computed by Equation (3).
Vf = Vfw/ [(Ald-Asc) + (Ard-Asc) /2)]                            (3)
where Vfw is the width of the valley floor, and Ald, Ard, and Asc are the altitudes of the left and right divides (looking downstream) and the stream channel, respectively. A significant relationship exists between the rate of mountain front activity and the Vf index. Consequently, the high Vf values conform to low uplift rates (Keller and Pinter 2002). The shape of a valley can also represent the Vf amount and uplift rate. Therefore, U-shaped valleys accommodate low Vf and high uplift.
Asymmetric Factor (Af): The asymmetric factor (Af) is a way to evaluate the existence of tectonic tilting at the scale of a drainage basin. The method may be applied over a relatively large area. Af is defined by Equation (4).
Af= 100(Ar/At)                                                   (4)
where Ar is the area of the basin to the right (facing downstream) of the trunk stream and At is the total area of the drainage basin. If the value of this factor is close to 50, the basin has a stable condition with little or tilting; while values above or below 50 may result from basin tilting, resulting from tectonic activity or other geological conditions such as lithological structure.
Hypsometric integral (Hi): The hypsometric integral is an index that describes the distribution of the elevation of a given area or a landscape. The Hi is independent of basin area. This index is defined as the area below the hypsometric curve and thus expresses the volume of a basin that has not been eroded. A simple equation that may be used to calculate the index is defined by Equation (5).
Hi = (average elevation - min. elev.) / (max. elev. - min. elev.)  (5)
Then Hi values were grouped into three classes with respect to the convexity or concavity of the hypsometric curve: Class 1 with convex hypsometric curves (Hi≥0.5); Class 3 with concave hypsometric curves (Hi<0.4); and Class 2 with concave–convex hypsometric curves (0.4≤Hi<0.5).
Index of Drainage Basin Shape (Bs): Horizontal projection of basin shape may be described by the elongation ratio, Bs, expressed by Eqation (6):
Bs = Bl/Bw                                        (6)
where Bl is the length of the basin measured from the headwaters to the mouth, and Bw is the width of the basin measured at its widest point. High values of Bs are associated with elongated basins, generally related to relatively higher tectonic activity. Low values of Bs indicate a more circular-shaped basin, generally associated with low tectonic activity.
Evaluation of Relative Tectonic Activity (Iat): The average of the six measured geomorphic indices (Iat) was used to evaluate the distribution of relative tectonic activity in the study area. The values of the index were divided into four classes to define the degree of active tectonics.
Results and discussions
Results of probabilistic seismic hazard analysis have shown that the minimum and the maximum acceleration for useful life of 75-year building is estimated as 0.33g and 0.45g and for 475-year one are 0.46g and 0.60g, respectively. These values are indicative of high risk in the studied area. Acquired values from geomorphologic indices and also acceleration zoning of the realm are indicative of high recent tectonic activities near Ipak, Hasanabad, Soltaniyeh and Avaj faults; they are extremely concordant with the obtained evidences and geomorphologic characteristics of the field samples. In this study, considering the diversity of the morphotectonic features, six morphometric indices relevant to the river channels, drainage basins, and mountain fronts were computed for every catchment, and consequently, a single index (Iat) was calculated from the these indices for each of 134 subbasins to define the degree of active tectonics. Finally, the Index of the Active Tectonic (Iat) was calculated through which the study area is classified into four tectonic activity classes, from very high to low; 1—very high (1.0≤Iat<1.5); 2—high (1.5≤Iat<2.0); 3—moderate (2.0≤Iat<2.5); and 4—low (2.5≤Iat). The distribution of the four classes of Iat has been presented in a well classified map. The indices have represented a quantitative approach to differential geomorphic analysis related to erosion and depositional processes which include the river channel and valley morphology as well as tectonically derived features, such as fault scarps. We also evaluated the outputs of the morphometric analyses based on field-based geomorphological observations. Thus, these results are proved to be extremely beneficial to evaluate relative rates of active tectonics of this region.
The values of Af show widespread drainage basin asymmetry related to tectonic tilting, particularly associated with Ipak fault. The values of Smf suggest that mountain fronts are tectonically active, and the values of Vf show that some valleys are narrow and deep, suggesting a high rate of incision. The parts with class 1 and 2 of the relative tectonic activity are located along the main faults of the region, such as Soltaniyeh, Avaj, Hasanabad and Ipak faults and show high correlation with observed landforms during the field investigations such as the direct mountain fronts, fault gorges, fault scarps, and deep v-shaped valleys. Besides, the high amount of the relative active tectonic index shows a good consistency with the recent tectonic activity, namely tilting and deformation of the Quaternary units, which is the indicative of the effect of compressive stresses, affecting the region.
In this study, according to the current tectonic activity using the Iat index, it was found that the study region represents a high current tectonic activity along the fault zones. The values of SL, Hi, and Bs were found to be high along Soltaniyeh, Avaj, Hasanabad and Ipak faults segments.
According to the earthquakes and probabilistic seismic hazard analysis in the study area, it can be said is worthy to note that some basins which are located among active faults, are seismically dangerous.  However, they show low relative active tectonic index (Iat)../files/site1/files/121/AleeiAbstract(1).pdf
Siamak Baharvand, Salman Soori, Jafar Rahnamarad, Maseoud Joudaki,
Volume 12, Issue 2 (10-2018)

Earth is a dynamic system. Change is one of its features. At its surface, there is almost no region that over the past few thousand years has not affected its neotectonic activities. In fact, it can be said that active neotectonic is changing the surface of the earth. Among geological methods for analyzing active tectonic movements, deciphering the geomorphology and morphotectonic nature play a very important role, because many geomorphic complications are sensitive to active tectonic movements and the geometric analysis of these complications provides evidence of the type, rate, and configuration of active tectonic deformations. Moreover, these geomorphic indices at a regional scale provide basic reconnaissance tool to identify tectonically active regions, their susceptibility to tectonic deformation, and level of tectonic activity.
In the presented study, tectonic activities and geological structural features of the Vark basin in Lorestan province, such as the discontinuities that may be detected on satellite imagery as lineaments, and in many cases control landslide occurrences, have been analyzed using the GIS and remote sensing.
Material and methods
Neotectonic investigation in the area: in order to analyze and to evaluate the tectonic movements in the Vark basin, considering the validity of geomorphic indices, longitudinal gradient (SL), river meanders (S), basin hypsometric curves (HC) and asymmetry factor (AF) have been used.  After calculating the desired indices, the tectonic activity of the area has been evaluated using the index of active tectonic (IAT).
Vark basin lineaments map derived from satellite images with proper resolution: using remote sensing techniques and visual interpretation of the OLI Landsat 8 satellite imagery, all fractures and lineaments of the region were identified and then by preparing the rose diagram, the trend of the lineaments of the area analyzed.
Landslide hazard zonation in the Vark basin: In this study, in addition to plotting landslide occurrence Points, eight other factors were also investigated. In order to provide a map of the factors affecting slip, the digital elevation model (DEM) in ENVI 4.8 and ArcGIS soft wares were used and the maps of slope, slope aspects, altitude classes, area geology, land use, topography and precipitation were prepared. Then, in order to zoning the landslide hazard, fuzzy logic method has been used. Fuzzy logic is based on the fuzzy layers and the fuzzy inference process.
Results and discussion
Analyzing the Neotectonic of the Area: as stated above, the relative active-Neotectonic (IRAT) index is derived from the interpolation of the morphotectonic indexes. In this case, after reviewing the morphotectonic indices of the study area and determining the activity rate of each indicator, the classification or prioritization of these activities were done. The results obtained from calculating the active tectonic index indicate that the study area with IAT is equal to one, has an active neotectonic.
Preparing the Lineation Maps of the Area: in this research, the aim of the data processing including satellite imagery and digital elevation model is identification and extraction of fractures and faults in the Vark basin. To this end, we can use the integration of the information layers derived from the above processes. In this step, all layers of information are logged into the ArcGIS software so that their overlap can provide a map of fractures and faults. On each information layer processed there is a series of lineaments recognizable that can be visually distinguished. After extraction of lineaments by comparing them with bundle compounds and maps derived from digital elevation model and geological map of the region, the lineaments of fractures and faults were separated from other lineaments and their shape file map has been prepared. In order to plot the rose diagram of fractures and faults, the Polar Plots ArcGIS Extension was used. The results obtained from this rose diagram showed that the dominant trend is the northwest southeast followed the trend in the region.
Preparing a map of landslide hazards zoning in the region and investigating its relationship with the lineaments: In order to overlap layers affecting the area's landslide hazard, Gamma fuzzy operator (λ= 0.9) has been used and landslides hazard mapping prepared. Based on the results, 12.40, 8.25, 37, 32.61 and 9.73 percent of the area are located in the very low, moderate, high and very high-risk classes, respectively.
In order to investigate the relationship between the lineaments and the landslide hazard maps as parameters that are affected by the tectonic activities of the area, the lineaments map was integrated with the map of landslide hazard. The results show that the most of lineaments identified in the study area have a northwest-southeast trend that are similar to the main faults of the region and Zagros. It can therefore be said that the lineaments are influenced by the faults and folds mechanism of the region. According to the lineament density in areas in places that are exposed to landslides, one can understand the close relationship between the lineaments and the landslide.
Based on the results obtained from relative active tectonics index, the Vark basin has an active neotectonic, which leads to an uplift in parts of the basin, as well as tilting in the southern part of the area.
In this research, the tectonic of the area, and then the relationship between the lineaments and the map of the landslide risk, as two phenomena affected by active neotectonic were reviewed. Investigating the lineaments of the region shows that the dominant trend is fractures north-west-south-east and following the trend in the region. In addition, analyzing the relationship between the lineaments with the map of the landslide hazard of the area shows that there is a close relationship between the lineaments and the zones with high risk of slipping.
Sassan Narimannejad, Alireza Jafari-Nedoshan, Ali Massumi, Abdollah Sohrabi-Bidar, Ali Ghanbari1,
Volume 12, Issue 2 (10-2018)

Local site conditions considerably influence all characteristics of the ground strong motion including the domain, frequency content, and duration. The level of such an effect could be considered as a function of geometry, properties of the materials embedded in the underlying layers, the site topography, and properties of excitement. Site effect fall into two categories: a) the effect of the surface soft layers triggered by the shear velocity differences between the soil layers and b) the surface and subsurface topography effects that lead to the wave reflection and refraction based on the site geometry, and subsequently enhance the level of amplification.
Since most cities have been constructed in the vicinity of or on sedimentary basins, geotechnical earthquake engineering devotes particular attention to effects of the sedimentary basins. Basin edge curvature deposited with soft soils are capable to trap the body waves and generated surface waves within the deposit layers. Such waves could create stronger and lengthier vibrations than those estimated in a 1D analysis that assumes the shear waves to be vertically propagated.
Although critically important, the 2D effect of the site has not been included in seismic codes and standards of the world. This might be due to the fact that the site effect depends on a number of parameters such as the site geometry, the type of wave excitement, properties of the materials, etc. that in return make it almost out of the question to make predictions about the effect. This study was an effort to compare the responses of four sedimentary basins with hypothetical geometries of rectangular, trapezoidal, elliptical, and triangular shapes in order to examine the effect of the geometrical shape of the basin on its responses and the extent of the response sensitivity to the excitation frequency of the wave. The study assumed the edge to depth proportion to be both constant and equal in all four basins so that the effect of the geometrical shape could be equally examined and compared in all four basins.      
Material and methods
In order to validate the results of the sedimentary basin modeling, firstly, ABAQUS finite element software was used to create a free field motion of a semi-circular alluvium valley in accordance with Kamalian et al. (2006) and Moassesian and Darvinsky (1987).  Then, the results from the model were compared with those from the above mentioned studies. The following descriptions are to present the model in details.
To evaluate the geometrical effect of the sedimentary basin on its response, the authors relied on the software to examine four sedimentary basins with the fundamental frequency (2.04 Hz). The basins enjoyed rectangular, trapezoidal, elliptical, and triangular geometrical shapes with a constant edge to depth proportion (49m to 300m respectively). The implicit method was also applied to perform the dynamic analysis. The materials were all viscoelastic and homogeneous. The soil behavior/treatment model was considered to be of a linear nature.  The Rayleigh damping model was used to specify the damping level. The soil element was a plane strain and SV waves (the Ricker wavelet) were used for seismic loadings in a vertical dispersion. The side boundaries (right and left) of the model were of a combinational type (viscous and free field boundaries); the down side boundary was composed of viscous. To achieve higher levels of wave absorptions, heavy columns were used as the free filed columns.
Next, it was the time to conduct the 1D analysis of the site. Three waves were in use in order to examine the effect of the frequency content of the excitation load on the basin response: 1) a wave with the dominant frequency of 1Hz that was out of the frequency range of all basins (2.04 Hz), a second wave with the dominant frequency of 2Hz that was close to the fundamental frequency of all basins, and a third wave with the dominant frequency of 4Hz. The waves were applied to a 2Dmodel. The results were compared with those obtained from a 1Dmodel in terms of the timing.
Then, the basin responses to all three waves (1, 2, and 4 Hz) were subjected to an individual analysis in order to examine the sensitivity of each basin response to its geometrical shape. Results indicated that while the responses of the rectangular and trapezoidal basins were significantly more sensitive to the excitation frequencies, the elliptical and triangular basins showed more stable behaviors to such frequencies. The final stage of the study was dedicated to examine the site 2D effect during the ground motion.
Results and Conclusions
According to the results of the present study, it could be suggested that the geometrical shape of the sedimentary basin has a significant effect on the responses of the field of seismic waves and that it could result in so different responses from the ones attained after a 1D analysis of the site. In addition, the pattern of the seismic waves’ responses is highly dependent on the geometrical shape and the frequency content of the seismic load. Also, the location where the maximum horizontal acceleration occurs along with the sedimentary basin depends on the excitation wave and varies accordingly. Further, it could be suggested that the site 2D effect results in both considerable amplification and an increase in the length of ground motion.
The results of the 2D analysis showed remarkable differences with their 1D counterparts: a 1.45 larger response for the rectangular basin, a 1.28 larger response for the trapezoidal basin, a 1.22 larger response for the elliptical basin, and a 1.19 larger response for the triangular basin.
With the frequency of 1 Hz where the excitation frequency is out of the basin range (i.e. the excitation frequency is below the lowest frequency of basin), the sedimentary basin did not show any signs of amplification and chaos (unlike two other frequencies); instead, it was a cause for de-amplification.
The frequency of 2 Hz that is subject to resonance resulted in amplifications (absent in 1D analysis) and there are traces of a reduction in the acceleration responses near to the edges of the basins. The proportion of the amplification (in the center of the basins) in 2D to 1D analysis was 1.4 for the rectangular basin, 1.28 for the trapezoidal basin, 1.22 for the elliptical basin, and 1.15 for the triangular basin.
Hadi Fattahi, Zohreh Bayatzadehfard,
Volume 12, Issue 5 (5-2019)

Maximum surface settlement (MSS) is an important parameter for the design and operation of earth pressure balance (EPB) shields that should determine before operate tunneling. Artificial intelligence (AI) methods are accepted as a technology that offers an alternative way to tackle highly complex problems that can’t be modeled in mathematics. They can learn from examples and they are able to handle incomplete data and noisy. The adaptive network–based fuzzy inference system (ANFIS) and hybrid artificial neural network (ANN) with biogeography-based optimization algorithm (ANN-BBO) are kinds of AI systems that were used in this study to build a prediction model for the MSS caused by EPB shield tunneling. Two ANFIS models were implemented, ANFIS-subtractive clustering method (ANFIS-SCM) and ANFIS-fuzzy c–means clustering method (ANFIS-FCM). The estimation abilities offered using three models were presented by using field data of achieved from Bangkok Subway Project in Thailand. In these models, depth, distance from shaft, ground water level from tunnel invert, average face pressure, average penetrate rate, pitching angle, tail void grouting pressure and percent tail void grout filling were utilized as the input parameters, while the MSS was the output parameter. To compare the performance of models for MSS prediction, the coefficient of correlation (R2) and mean square error (MSE) of the models were calculated, indicating the good performance of the ANFIS-SCM model.

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