JOURNAL OF FACULTY OF ENGINEERING (UNIVERSITY OF TABRIZ)
Year:2008 | Volume:37 | Issue:3 (55) CIVIL ENGINEERING|Papers Count:11

Life-detecting is the major stage in rescue management once earthquake occurs. Nowadays, many activities such as researches, arranging structures and programming are done for this purpose. Most of these efforts are based on one dimensional data which considers spatially and temporally independently. Life-detecting analyses are two dimensional and occurre in special time and position. Therefore it is necessary to consider time and position together for modeling and analysis of such phenomena. The goal of this paper is to model the activities of life-detecting teams with respect to their spatio-temporal dimentions. For this purpose, Hagerstrand theory was taken as the base model. Considering the affordance theory in a task oriented way, a novel model for managing life-detecting team activities in space and time was developed. The model can be implemented in Spatio- Temporal GIS and other researchers can extent it to manage the whole rescue team activities. In order to assess the model, a case study was simulated through normal and suggested methods. The comparisons between them have done through object oriented manner in C++. The statistical analyses on the results show an average of 30% improvement in groups' activities.

Researches show that concretes containing 25 to 35 % slag powder (as alternation for Protland cement) obtain compressive strength CS about 85% and 97% of the control specimens (without slag) at the ages of 28 and 90 days respectively. These concretes, also, recorded less growth rate of the CS than the control specimen at early ages (<28 days). In order to increase the early CS of these concretes and acquire 28-daysold CS about control specimens, this investigation was carried out using various percentage of the silica fume replaced with known quantities of Prortland cement. The results revealed that specimens containing 5% silica fume along with 25 to 35% slag powder displayed 5.2% and 13.3% higher than CS of control specimens at the 28 and 90 days respectively. In other part of the study the CS of the concretes containing slag powder cured with water comprising 2.5% MgSo4 as well as 2.5% NaCl were evaluated. Slag-contained specimens, which were placed in above mentioned curing situation, showed less CS at 28 days than control specimens whereas at the age of 90 and 180 days CS of the specimens were higher than the control specimence. The 25% slag-contained speciemens placed in sulphated situation at 180 day old stage showed 325 Kglcm2 CS which was 14.44% higher than the control sample attaining the best result. here with material and geometric nonlinear analysis. In this paper, buckling behavior and ultimate capacity of built up castellated compound columns are investigated using ANSYS software. A brief of results is reported on for a number of CPE sections in different boundary conditions. Also is presented slenderness-load curve by using of Jandel software, which is a useful tool for investigation of ultimate capacity of the columns.

This study presents the effect different levels of cement content with compressive strength, capillary water absorption and chloride ion diffusion in concretes with constant water/cement (w/C) 'ratio. W/C ratios were 0.4, 0.45 and 0.5 that for each of them four concrete mixes were prepared with cement contents 300, 350, 400 and 450 kg/m3. Type II Portland cement and aggregate with maximum particle size of 19mm were used. Test results indicate that at constant W/C ratio, compressive strength increases and water absorption and chloride ion diffusion decreases when cement content in the mix decreases from 450 to .350 kg/m3. Similar results is also observed when cement content increase from 300 to 350 kg/m3. As a result, it is expected that for W/C ratios ranged from 0.4 to 0.5, mixes with cement content 350 kg/m3 have more suitable performance in aggressive environment than other mixes.

The aim of this investigation is to study the flow characteristics over the broad crested rectangular weirs with sloped upstream and downstream faces. This paper reports the effects of upstream and downstream face slopes on discharge efficiency of weir and the velocity profiles .The results showed that the critical flow section formed over the weir crest and was independent from flow discharge. As the downstream face slope was decreased the curvature of streamlines at downstream edge of the weir became much smoother. 'It was found that the modular limit of the sloped broad crested weir with downstream face slope of 10°, relative to standard broad crested weir, was increased from 69% to 96%.The results revealed that the discharge coefficient does not change with downstream slope. However, the increase in upstream face slope increases the discharge coefficient relative to standard rectangular broad crested weir. It was found that the discharge coefficient of sloped broad crested weir with upstream face slope of 10o was increased about 22% larger than the standard broad crested weir. By decreasing the upstream face slope, the uprising of the eddy currents at the junction of sloped and horizontal faces was found to be decreased.

Most of structural destructions take place because of components fracture. This event occurred by cracks that their development is considered as a serious threat for the treatment of structure. Therefore the exhibition and distinction methods of crack were the subject of wide verifications during last decade. Considering the local hardness differences arising from cracking and its effect on the treatment of structure, this article studies the distinction of internal crack in cantilever beam. Specimens were placed on harn10nic analyses and the base of recorded reaction was analyzed by Wavelet transform. Also this text offers the sensitiveness of the above method due to the depth. angle and situation of crack, and possibility of its identification, in various conditions.

In this paper, the scour process around cylindrical piers due to steady currents has been investigated using a physical model. The cross sectional shape of the piers (circle, ellipse, rectangular and composite), the laying direction of the pier with respect to the flow, the bed sediment particle size, aspect ratio of the length to breadth and also the Reynolds number, were the main variable parameters in this research. The experimental results have been compared with those of the other researchers. The tests have been carried out under clear water conditions and the whole scour process has been monitored. The results of investigations have shown that the cross sectional shape of the piers had great effect on the maximum scour depth, and it reduced up to 30 percent in some cases. Finally, with the knowledge of the different effective coefficients of the scour process a formula has been suggested for estimating the scour depth.

The object of this study was to clarify some of the fundamental problems occurring in reinforced ASR concrete slender columns. Preloading of ASR concrete results in an improvement in the mechanical properties ASR causes a reduction in axial load capacity of slender columns. The failure of an ASR column was accompanied by a large delamination of the cover. As ASR concrete showed very substation reduction in tensile strength, this might be the cause of cracking and delamination of ASR columns. This may also be the reason why columns fail before reinforcement reaches its maximum capacity. The expansion of ASR concrete in the columns will increase the compressive stresses and result in tension in the reinforcement.

Scour hole development, its time variation and evaluation of its equilibrium state are of great importance in designing and implementing of abutments. Variation of scour hole dimensions and their development have a substantial effect on the scour mechanism. In this research, time variation of scour hole at short wing wall abutments was investigated. The results obtained showed that scouring 'starts from the upstream comer of the abutment and upstream slope of the scour hole, termed the dynamic angle of repose was found to be 18% greater than the angle of repose of bed sediments. Time variation of scour hole dimensions, namely dimensionless length of scour at upstream, downstream, width of scour with time found to be logarithmic. The relationship between scour depth and time was also logarithmic and 60% of the maximum scour depth took place at the first hour of the experiment. The results obtained also showed a good agreement with other works.

Spur dike is a hydraulic structure used for protection of river banks. In the past few decades, the use of spur dikes for stability of the outer banks 6t; rivers has attracted the attention of hydraulic engineers. This study experimentally measures the 3D flow field in the 90 degree bend with T-shaped spur dike in section 75-degree. The experiments were carried out in a channel with a 90 degrees bend. The three-dimensional Acoustic Doppler Velocimeter (ADY) was used for measuring the flow field. The three-dimensional time-averaged velocity in the 90-degree bend with spur dike was measured. Then the comparison of the three dimensional components of velocity was made in different sections and the differences of the flow pattern along the bend was analyzed. The observations showed the effect of the spur dike on the secondary flow patterns and in the formation of the subsequent secondary flows. Some horizontal vortices with a counter-clock-wise direction were also be observed in the up and down stream of the spur dike near the outer bank. In addition, the vortices and reverse flows in the up and down stream of the spur dike as well as the changes in the longitudinal, lateral and vertical velocity components are investigated in this study.