الفهرس 
INTRODUCTIONOnly 14 pages are availabe for public view
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Abstract
A brief description of the latest modeling techniques adopted to analyze steel reinforced concrete walls under blast loading analysis and the latest studies and design approaches are summarized. A macro-modelling technique utilizing the OpenSees software embedded layered-shell element was utilized and verified against experimental and analytical data under both quasi-static loading and blast loading. The utilized model was used to perform a parametric study of the behavior of reinforced concrete walls under both quasi-static and blast loading to reflect the effect of different boundary elements (BEs) configurations on the performance of those walls, either under quasi-static loading in phase one of the study, or under varying blast load scenarios in phase two of the study. After that an extended parametric study was conducted in phase three of the study to investigate the effect of the boundary element configuration, the thickness of the BEs, the boundary conditions, the steel reinforcement ratios, the applied axial load, and the aspect ratio of the wall on the resulted performance of the studied walls. It was found that the first added boundary at the middle of the wall increases the load resistance by about 20% more than when using multiple BEs. while each of the extra added boundary elements increase the load with nearly equal percentages, and this conclusion is valid on the different thicknesses of boundary elements. And it was also noticed that Embedded BEs with configurations BW1 with one BE at the middle of the wall and BW2 with two boundary elements at 20% of the length measured from the edges can be good choice under moderate applying load levels with satisfying economical cost while adding satisfying resistance to the wall. It was also concluded that to best optimize the number of the used BEs, it is recommended to have the BEs spaced at distances not exceeding 1.5 the height of the wall and preferred not to be less than 0.6 the wall height since it became less utilized, and in case of using two boundary elements, it is preferred to position them at 0.2L from the wall ends. fragility curves of the basic six walls were generated showing maximum variation in collapse probability with charge impulses varying from 5 to 15 MPa.Sec, with a maximum difference of 33.86% between wall BW5 and wall W at impulse of 9.84 MPa.sec. After that, the performance difference between different walls is reduced until the minimum of 15.13% difference at the maximum applied impulse of 37 MPa.Sec. It was found that using boundary element with thickness of 35 cm achieved the highest reduction in displacement and damage relative to the added BEs, with 9% damage per add BEs ratio in BW2-B35 and 8.14% displacement reduction per add BEs in BW5-B35. Increasing the vertical reinforcement of the web to (0.628%) (100% increase) leads to enhancing the performance and reducing the peak displacement for all the different wall configurations with a maximum reduction percentage of 25.7% with the case of wall (W), and thus the effect of web reinforcement increase is lowered until the minimum value of reduction of 6.6% with the case of wall (BW5), which has the maximum number of BEs, While changing the horizontal reinforcement has minimal effect on the walls’ performance. Increasing the BEs reinforcement has reflective influence on the behavior of those walls. This enhancement in behavior from reduction in peak displacement point of view shows that BW2 shows the highest reduction in displacement per used BE with 13.6%, while BW1 shows the lowest enhancement compared to the other wall configurations with only 3.9% reduction. Likely, Reducing the BEs reinforcement had negative influence on the different wall configurations, with maximum increasing in displacement of BW5 with 6.4% resulting from reducing the reinforcement percentage of each wall by around 0.5%. It was also found that the applied axial forces on a wall under blast wave reduces the achieved support rotation, while resulting in increased damage in the compression fiber of the wall, adding axial load of 20% the ultimate wall capacity resulted in maximum reduction of displacement in the case of rectangular wall type (W) with 40.8% in with respect to the case without axial load, While the resulted level of damage was increased by a maximum of 40.9%. Lastly, phase four of this study generated P-I diagrams for different configurations of walls with different thicknesses of boundary elements, and those generated P-I diagrams assured the findings of phase three of study, moreover they presented a quick design aids in a graphical way to facilitate the decision making of selecting a suitable wall to withstand a defined blast scenario.