JOURNAL OF CIVIL ENGINEERING ISLAMIC AZAD UNIVERSITY
Year:2010 | Volume:2 | Issue:1|Papers Count:8

This study has been carried out for investigating the need for an appropriate and fast seismic analysis method to be applied in performance based design (PBD), and show the application of Endurance Time (ET) method and it’s advantages in PBD. As a secondary goal, potential of this method in more complicated nonlinear domains is assessed. Application of ET and its advantages in PBD is shown with an example of BRBF building after modeling nonlinear interactional behavior of beams and columns, and also modeling isotropic hardening behavior of BRBs by calibration it with experimental results. For this purpose, in ET and NTH almost all of important response and demand parameters of structure containing all stories drifts, stories’ shear, interaction of axial and moment force in column, strain in BRBs and dissipated energy balance in different parts of structure are compared. Also reliability of nonlinear static analysis method as a conventional codified method is assessed.

Sea level rises have had an increasing trend in the last decade. Due to satellite measurements, the sea level data have an unprecedented accuracy today. The tide gages measurements have shown a 1.8±0.3 mm/year increase in the sea levels for the last 50 years, however the measurements of TOPEX/Poseidon and Jason-1 satellites shown a 3.1±0.4 mm/year increase for the years after 1993. In this paper, a review on the sea level rise, and also the reasons according to the past researches will be made.

Internal erosion is one of the most important causes of failure in embankment dams, resulting an increased seepage flow due to loss of fines. Methods for seepage monitoring and internal erosion detection are therefore essential for the safety of earth embankment dams. Many existing seepage-monitoring systems are not however sensitive enough to detect small changes in the seepage flow. Temperature measurement is a new method for leakage detection in embankment dams that is able to detect the effects caused by time dependent processes such as internal erosion and small seepage flow, despite conventional methods. This paper presents analyses of monthly temperature measurements in Shamil embankment dam located in Hormozgan Province, Iran for seepage evaluations and internal erosion detections.

For scheduling some projects that have repeatable bases as highway constructions and high rise building we have to use some special method like LOB and LSM instead of CPM. So far for resource leveling in these methods (LOB, LSM), it has been suggested various algorithms like mathematical algorithms and genetic algorithm which have many advantages in comparison with other methods. In this paper first, we explain mathematical and genetic algorithm and we examine two case study for each methods and then we make an comparison between these. At the end we study advantages and disadvantages of each algorithm in various situations.

A main reason of seismic vulnerability of asymmetric buildings is due to additional displacement demands causes by tortion. It has been found that Tuned Mass Damper can reduce the maximum displacements of this structures effectively. However in many cases, it is important to reduce both displacement and acceleration simultaneously. In this paper, seismic behavior control of linear and nonlinear buildings with different torsional properties are studied when different dampers at different locations are used. The reduction in maximum of edge displacement and accelerations are assumed as response parameters. The results indicate that Tuned Mass Dampers is effective in simultaneous control of acceleration and displacenment in linear structures, and its effectiveness increase with nicrease in the mass of Tuned Mass Damper. For torsionally flexible buildings, the most effective cases are installing damper at stiff edge or at both edges. This system in simultaneous control of acceleration and displacement in nonlinear structures isn't very successful.

Simulation of embankment dam-break events and the resulting floods are crucial to characterizing and reducing threats due to potential dam failures. The studies of dam break are necessary and important in university investigation, the government's planning and investment in downstream of the dams.Aidoghmosh-dam constructed in Myaneh city of east Azerbaijan province in Iran. In this research, considering the importance of the dam break's studies and flood routing due to it, based on the previous researchers studies, new relations for estimating of the dam breach parameters (breach width, side slop, time of failure and peak outflow) were established and compared with the recent relations by collecting from 142 case studies. The uncertainty of new provide as case study, relations was evaluated and their significance limits were presented as probability. By using the BREACH and FLDWAV application software, the studies of Aidoghmosh earth dam breach were examined. Substitution of geotechnical conditions instead of geometric conditions in the time of collapse in dam, in BREACH model, gives better results. According to the results obtained from the examined dam breach, wastewater treatment plan, four connective bridges of the railway, and some part of the Rah-Ahan residential town are exposed to the danger of the flood resulting from the dam break.

Anzali Wetland is a distinguished coastal wetland in the southern coast of the Caspian Sea in north of Iran. This wetland is connected to the Caspian Sea through the Shipping Channel and is supported with freshwater by 10 major rivers. Anzali Wetland plays a key role as a habitat for many indigenous plant and animal species. It is believed that the ecosystem of the wetland is threatened by inflow of excessive amounts of Chemical Oxygen Demand (COD), Total Nitrogen and Total Phosphorus. Chemical Oxygen Demand (COD) is a representation of organic pollution. Changing in discharge of rivers and precipitation and Caspian Sea level changes due to seasonal climate changes has some effects on COD concentration of the Wetland. In this paper, a two-dimensional depth-averaged model for hydrodynamic and advection-dispersion is used to determine COD distribution in Anzali Wetland. Forcing actions of Caspian Sea fluctuations, evaporation and precipitation, rivers input and wind is taken into account. According to available field data, the model is executed for three periods which are dry (23rd August-1st September), early rainy (13th October-25th October) and mid-rainy (2nd December-14th December) season. The simulated values are compared with observed ones at 16 stations. The results indicate that COD concentrations at all the stations were high denoting noticeable organic pollution in the wetland especially in the dry season.

Knowledge Management (KM) and Logistic Management have become the important success factors in this emerging era of information and competitive. This paper discusses the sharing knowledge in Logistics and SCM and presents a hierarchical model of it. In this research a knowledge management system framework is proposed, which has the characteristics as intelligent, flexible, cross-platform and automatic. The proposed model is useful in the last chain of supply chain of food industries and can be applied to analyze and investigate the rule of KM in food industries.