JOURNAL OF NEW APPROACHES IN CIVIL ENGINEERING
Year:2018 | Volume:2 | Issue:3 |Papers Count:6

Trusses is one of most usable structures in engineering. Truss is combination of bar elements created. Triangle shape is most stable possible are formed by bar elements in truss. In this research, with using statistical analyses methods effects of per parameters such as material, diameter of bar, applied force to joints, combination of interior angles in vertical and horizontal displacement in Pratt truss have been evaluated. For this purpose, 45 models in Sigma/w analyzed. Then, statistical analyses on data’ s by using SPSS program have been performed and continuity of parameters with considering of displacement in joints was evaluated. In finally, a relationship for estimation of maximum displacement in joints of truss has proposed. Results of this study showed that in single parameter mode, a scenario with combination bar diameter, elastic modulus and angles between elements results much better than scenario with considering force in joints. According to results of Pearson test it can be explained that maximum displacement in joints have liner direct relationship with diameter, elastic modulus, applied force and angle between elements.

In this paper, the effects of irregular mass in height for structures has been investigated. To achieve this goal, two five and ten stories concrete moment resisting frames are modeled using Seismostruct software and subjected to seven different accelerograms. To evaluate the seismic performance of the studied structures, incremental dynamic analysis (IDA) has been used. The results reveals that the seismic capacity of the irregularly structures reduced, and therefore, it is suggested that mass irregularity in height be avoided as much as possible.

Heavy cost and growing losses, injury and objects destruction, deep psychological, cultural and social costs of traffic accidents are an important issue for officials, managers, politicians, as well as for the traffic police of the country. The needed to calculate the cost of traffic accidents and to find scientific, logistic and systematic ways to solve this problem is felt more quickly. In addition, determining the cost of traffic accidents highlights the imposing heavy burdens on the community, contribution of the sectors involved in the accidents. Assessing the cost of traffic accidents as a benchmark for comparing and deciding and determining the effectiveness of actions have been taken reduce disasters. Main idea in this research is estimation cost of road accidents in Iran based on latest accident statistics of 1395. Accordingly, the approximate cost of all road accidents occurred in 1395, and hence the cost of each accident in terms of damages and morality was obtained.

The unpredictable nature of earthquake has led to engineers to the statistical and probabilistic studies for investigating of the effects of earthquake phenomenon problem. The movement recorded of the ground under influence of earthquakes in near fault zones are different from far fields. The pulse phenomenon in the history of acceleration, velocity and displacement is one of the characteristics that distinguishes near and far field earthquakes. In this research, after scaling the time histories of accelerations, structural analysis of reinforced concrete bridge with four 22 meters openings has been performed by dynamic analysis of liner history. Then, the results in the form of internal forces of the members and displacements in a particular joint under the time history of accelerated incidents are presented. The result of investigating the effects of bridge distance from faults on internal forces of columns due to earthquake showed that axial forces including compressive, tensile and torsional moment in columns have the highest value when near field earthquake occur. Also, the result of evaluating the effects of bridge distance from faults on internal forces of deck due to earthquake showed axial force and bending moment at time of far field earthquake happen have highest value. Although, this amount is dependent on severity of earthquake.

Based on experience of past earthquakes, irregularity in building is one of the major cause has been damages to structures. One of these irregularities is the discontinuity of vertical elements such as displacement of position of shear wall in height, considering that in design versus lateral forces, the forces applied to buildings should be transferred from the point of their effect through the whole system to the ground, and the path of forces must be completed. Where, there is an interruption in the normal transition of forces, problems have occurred. Weak story or torsion effects created in floor of building. In multi-story buildings, columns and shear walls must be positioned along each other. With considering the limitations of codes and architectural requirements, there is a question in minds of engineers that it is possible to violate this common rule and to design discontinued shear wall in height. Although, Iranian code No. 2800 (Ver. 4) warned against the design and use of buildings with discontinues shear wall and recommended these types of systems should not be applied. Therefore, in this research, the seismic behavior of irregular flexural concrete frames in terms of discontinuity in shear wall have been evaluated. Also, building coefficient of behavior, displacement control an irregularity effects in seismic behavior of frames have been considered. What is important in this research, moving the shear wall in which floor can have the least effect on structural response. In this study, models analyzed under nonlinearity statically condition with using SAP 2000 program.

Today, the use of underground structures and their numerous uses in urban and interurban transportation has been found to be of great importance and has become one of the topics discussed by engineers in the field of construction and civil engineering. One of the issues that have attracted the attention of the researchers in these structures is the resistance of these structures to the rejection of dynamic loads. Therefore, in the present article, the seismic behavior of the tunnel under the earthquake record in the near field has been studied with regard to overhead and overhead. To analyze this research, the seismic behavior of tunnel line 2 of Tabriz city trains was selected and using the abacus software and available geotechnical reports, the 2nd line of Tabriz city trains was studied. The results of this study indicate that, in case of overturning, the amount of deformation and strain in the tunnel crown increases, this increase is proportional to the earthquake record. The results also show that the behavior of the tunnel in case of overhead operation in relation to the non-overhead state is not under the earthquake record of the near-frontier zone, which is sensitive to soil layering, and the variation of the tunnel crown under both acceleration maps of Bam and Varzaghan in all sections of the Earth's crust is close to It has been. The results also indicate that on the route of line 2 of the city of Tabriz, despite the change in the characteristics of the soil mass in the path, the tunneling behavior has little sensitivity to soil layering in the path and if the tunnel is located at a depth of 22 meters from the ground level under the earthquake record There is not much deformation in the crown of the tunnel.