civil engineering
Mohammad Memar Eftekhari; Mohammad amin Kadivar; Mohammad Rezaei
Abstract
Blast load is a load with a dynamic nature similar to an earthquake, with the difference that its effects take much less time than an earthquake, are more intense, and directly affect the structure itself. Therefore, in this case, in addition to carrying out the usual retrofitting, it is necessary to ...
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Blast load is a load with a dynamic nature similar to an earthquake, with the difference that its effects take much less time than an earthquake, are more intense, and directly affect the structure itself. Therefore, in this case, in addition to carrying out the usual retrofitting, it is necessary to reduce this explosive effect by changing the architecture of the structure. One of the solutions for this problem is the dual-purpose use of seismic elements such as shear walls, which can not only resist earthquakes but also resist explosive loads. Meanwhile, concrete structures have shown good resistance to explosion compared to steel structures, and one of the design methods in these types of structures is the use of concrete shear walls. One of the solutions to reduce the dimensions of the columns is to use a concrete shear wall. One of the capabilities of this method is the possibility of creating an opening in it, and it reduces the limitations created in the architectural discussion. In this research, the performance of arched concrete shear wall with opening against explosive load has been investigated, and the considered samples with and without opening have been compared. Also, the effect of compressive strength of concrete has been investigated. Finally, it was determined that when creating the opening, full care and inspection should be done and the area around the opening should be reinforced. Arched concrete shear wall with 10 cm thick opening has performed best against explosive load.
Rahman Sharifi; Hamed Ali
Abstract
There are many different methods to modify the mechanical properties of saturated clayey soils. It may be chosen depending of location and function of the structure. among those methods, preloading in presence of vertical drains and installation of stone columns are similar together and it is the cause ...
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There are many different methods to modify the mechanical properties of saturated clayey soils. It may be chosen depending of location and function of the structure. among those methods, preloading in presence of vertical drains and installation of stone columns are similar together and it is the cause of comparison. In this thesis, each mechanism of modification of soil was studied lonely and then the results of every method were compared with all together. Subsequently the mentioned approaches were graded technicaly. For this reason, a two dimentional finite element software was used to make the models. It should be necessary to forcast the results of choosing one approach, because there is no proper procedure available for engineers to choose one of these method as the first index, and also the long time that must be spent for in situ consolidation.the results show that the finite element program has the ability of simulating the consolidation phenomena in saturated clayey soils and declare that installation of stone columns is better than preloading by installation of vertical drains. Of course, there are many parameters influences the selection of superiority.