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  Aims This study has been done to investigate the effects of access road network of Arasbaran forest areas on erosion in order to achieve appropriate criteria for sustainable development in forest areas while protecting forest soil.
Materials & Methods This research was carried out to introduce the SEDMODEL and its capabilities in estimating the production of sediment from road construction Sutanchay watershed in Arasbaran forest, located in the northwest of Iran. From road networks, 10km selected for research. Initially, the maps of geology, slope, rainfall, and drainage density, were prepared in the GIS system. Then, excavation trenches, road surface coverage, and traffic volume were examined in 34 stations through field surveys. The statistical method of Fisher distribution was used to compare the model estimation and observation values.
Findings Statistical analysis of the data showed that there was no significant difference between sediment delivery and Metric method in the erosion assessment resulting from access roads. Standard Error of the metric method and the SEDMODEL was calculated to be 1.34×10^-3 and 1.37×10^-3, respectively. The results showed that sedimentation caused by road surface was more than 19,000tons, of which 240ton are related to 3km of asphalt road and the rest are related to 7km of dirt road. Total sedimentation of the watershed was estimated to be 46,000ton.
 Conclusion The application of sediment delivery model provides a realistic estimate of forest soil erosion caused by the road network. This model can be considered as a planning criterion in the sustainable development of forest areas.

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Vibration due to train movement has been concerned since the advent of rail transportation systems. Nowadays this subject is more important by increasing the speed of trains and wagon weight and development rail way in urban area. Different methods and techniques have been proposed to reduce these vibrations by researchers. In this study, geotechnical modeling of trench barrier isolators to reduce train vibrations are investigated by numerical modeling. Trench barrier according to location are divided into two categories: active and passive. Active trench is located near the source load but passive trench is located near the structure that needs protections. The main focus of this research is the effects of trench depth on efficiency of passive trench barrier. In advance by considering the wagon weight and distance between the wheels, the load in terms of time domain by calculating Fourier spectra and considered effective frequency range, the load-time function is determined. Then, a series of nonlinear finite-element analyses were carried out to study effect of trench depth. The depths of trench are considered 0 to eight meters in analysis. Viscous damping was considered by means of Rayleigh methods. The coefficient of mass and stiffness matrices are defined by modal analysis. Then, modeling of rail, sleeper, ballast, sub-ballast and soil layers is conducted to analyze wave vibration propagation due to train movement and evaluation of amplitude reduction due to trench barrier. Mohr Coulomb failure criterion is supposed for soil, ballast and sub-ballast layer and a linear elastic behavior was assumed for sleeper. Infinite element boundaries were used at the lateral sides of the finite element mesh for prevention of wave reflection. The dynamic response analysis was based on input time historical wagon load which determined in previous section applied at the sleeper.Thereby the studying of deformations and displacement and particle velocity of the elements of the model, the effects of the trench barrier on before and after trench, are considered. Results indicate that increase in trench depth is effective on vibration reduction. This means that by increasing the depth of the trench, amplitude of deformation becomes more reduced. It also increases the depth of the trench, reduces the dominant wave frequency vibrations. On the other hand, by increasing the depth of the trench, amplitude reduction ratio has a significant decreasing that means increase efficiency trenches. The relationship between depth and amplitude reduction ratio (Arr) was introduced as a quadratic function. For validation of modeling, theory equation of amplitude decreasing is compared with numerical modeling. The result showed that there is a good accordance between numerical model and theory equation at different distance.The minimum depth of the trench should be selected based on different parameters. To define depth of trench should be note that the reduction due to trench should be significantly greater than the decreasing wave amplitude due geometric and material damping. Reducing the required to mitigate the potential damage of protected structures and economic and implementation considerations are important factor in determination of final depth of the trench barrier isolator.

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In today’s society, pipelines as vital arteries play a significant role in maintaining people’s peace and satisfaction. According to growing developments in societies, the necessity of constructing, refurbishing, repairing, and maintaining underground installations such as petrol pipelines, gas, water, wastewater, runoffs, and connections is considered as the indispensable part of civil and installation operations. Regarding problems stemming from the open trench excavation methods and growth of underground installations, using trenchless technologies in the construction industry is increasing in order to solve the problems more economically and effectively. The present project aimed at recognizing and ranking the most important effective factors in accepting the trenchless technology in Iran. This research has a practical target and has been performed by the survey and the describing method. The statistical population of this research includes middle managers, contractors, and civil projects engineers of Isfahan province. In this regard, a sample of 87 people was randomly selected and the questionnaire was distributed among them. Eventually, a total of 68 questionnaires were collected with favorable consistency. This questionnaire has been designed by the investigator according to the Likert scale with high stability. Accordingly, the factors were grouped in the form of 28 criteria and 8 major groups as the effective factors on accepting the trenchless technology in Iran. Descriptive and inferential methods and the Friedman test were used to rank the effective factors, and the SPSS software was applied to analyze the data. Among the 8 major groups of executive management, environmental, demographics, technology, economically, project productivity (construction management), organizational, and individual had the first to the 8th rank, respectively. In addition, control system, risks, environment, budget, chief executive officer (CEO), special and geographical performance, and direct costs ranked the top among the 28 factors.

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Natural events and disasters always have a devastating impact on human settlements and incur economic and social effects on societies by destroying buildings and infrastructures. One of these destructive phenomenons is landslide that could damage communities, meadows and forests, communication lines, and monuments extensively in many parts of the globe, especially in mountainous countries such as Iran. Some information is currently available about the morphological cause and effects of some apparent cases. However, the destructive effects of this phenomenon on ancient settlements have not adequately been mentioned. This study examines an ancient landslide by combining data from two seasons of archaeological excavations of Tepe Mehr Ali, located in Fars province, and related interdisciplinary studies. The results of the excavations, geological evidence and morphology of the site indicate that the southern slope of the mound (about 35 degrees) to Balangan River, represent a landslide event leading to the abandonment of this site for some time during settlement periods.