Population growth makes public transportation needs increase, one of the needs for the availability of population growth is the need for availability of railway. However, the available land for railway construction is very limited, therefore experts design the railway using a tunnel. Risk analysis in Railway projects with tunnel design is carried out to determine the most important type of risks. The results of this research show that the railway project with tunnel design has the same risks as railway projects with other designs, there are site risk and environmental risk. After finding the most important risk, use the Multiphase risk management method to manage this risk.
One of the important problems in earthquake geotechnical engineering is liquefaction phenomenon that happens in loose saturated granular soils. This phenomenon can cause great damages to underground structures and buildings and lifelines. Liquefaction resistance of soils can be evaluated by experimental and field tests. In this research, results of liquefaction potential evaluation based on standard penetration test (SPT) were proposed. Case study area is Ghazan Chay Dam at Southeast of Khoy city at West Azerbaijan province in Iran. In this study 18 boreholes was collected. With considering type of soils and ground-water table level liquefaction potential evaluated. Then, liquefaction potential index (LPI) assessed. Obtained results showed that almost more of 50% alluvium sediments deposits is included sand and silty sand. Also, liquefaction potential hazard with considering ground water table level is high.
Weirs are one of the widely used hydraulic structures for measuring discharge in open channels. This study applies two artificial intelligence models named artificial neural network (ANN) and genetic programming (GP) to predict discharge flowing over semicircular weirs with different openings including sharp and semicircular crests. The considered data base was selected from the literature. The results of AI models were compared with those of two empirical formulas, which have been developed based on the same data for this purpose. Four evaluation criteria were considered for comparing the estimated discharges. The results obviously indicate that GP outperforms others based on the considered criteria.
Sharing project outcomes are believed to be vital in aligning interests of contracting parties. This research derives an optimal form of multi agents-multi outcomes construction contracts through solving an optimization problem based on principal-agent theory. The attention is paid to contracts with a risk-neutral client and risk-averse agents. The paper shows that the proportion of outcome sharing with an agent should be high when outcome variance is low or the contribution of the agent toward the outcome is high. The paper also shows that agents who are more risk averse, should receive a low proportion of outcomes sharing.
To reduce the number of private cars and respectively to decrease the side effects of congestion in central business districts (CBD) of metropolitans is one of the main purposes of implementing transportation demand management policies. This study uses a set of stated preference data to investigate the relationship between land use characteristics, five TDM strategies and modal shift from private car. The target group of the study includes commuters who often drive to CBD for work or study during the morning peak hours. Results reveal the effectiveness of some of the tested variables on the choice to give up driving.