نوع مقاله : پژوهشی اصیل (کامل)
کلیدواژهها
موضوعات
عنوان مقاله English
نویسندگان English
Retaining structure or retaining wall is a wall that acts as supporting structure and the stability of another structure. This wall is used for preventing collapse of soil and generally wherever lateral support is needed. The retaining wall can be designed as gravity, cantilever and supported. Considering that the retaining walls are essential in protecting the related structures to them, therefore, studying the dynamic behavior of these structures is very important due to the financial and human damages. Such structures should be stable against the forces acting on the wall. In addition to static loads, which are always an inseparable part of the calculations of such walls, forces such as cyclic forces caused by the movement of machinery and also dynamic forces caused by earthquake occur on the wall during the period of operation. These forces can be effected on retaining walls and should be investigated and evaluated. Trying to investigate and analyze the dynamic behavior of different retaining walls is one of the most challenging for different researchers.
The wavelet theory in the dynamic analysis of the issues related to civil engineering is going to be widespread. This research aims to investigate the effect of using wavelet theory in the dynamic analyses of concrete retaining walls. For this purpose, a soil medium along with concrete retaining walls with different dimensions (heights) are considered. Dynamic analyses are performed based on the finite element method. In the first stage of modeling, the Sarpol-e Zahab earthquake record is filtered during four steps using the discrete wavelet theory. The numerical models are prepared and subjected to the available records. The percentage of the difference in the results of the analyses done with the records obtained from the different steps of filtering record with wavelet compared to the analyses done with the main record, along with the reduction of the time consumption, is evaluated. As expected, the best match of the post-filtering results to the main earthquake results is for the first-step filter. It can be seen that even the first step filter reduces the analysis time by about 60%. Based on the obtained results, the difference between the results obtained with the filtered records becomes less compared to the main earthquake with the increase in the height of the wall. It has also been observed that acceptable results are still obtained, and the analysis time is reduced by almost 80% until the third step filter.
It should be noted that the Mohr-Coulomb behavioral model is used in the conducted analyzes in this research. This behavioral model is not inherently able to model hysteresis damping behavior at low strains. Therefore, this issue can affect the results of deformations and stresses obtained from dynamic analysis. However, the purpose of this research is to evaluate the performance of the wavelet in the dynamic analysis of the retaining wall. Considering that in all the analyses (both the performed analysis with the main earthquake and the performed analyzes with the wavelet filtered records) the same structure and trend are used, it can be concluded that the effect of using the wavelet compared to the main earthquake gives an acceptable overview and quality
کلیدواژهها English
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