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Dynamic Analysis of a Multistory Frame RC Building with and Without Floating Columns
Ahmed Ibrahim,
Hamed Askar
Issue:
Volume 9, Issue 6, November 2021
Pages:
177-185
Received:
22 September 2021
Accepted:
26 October 2021
Published:
10 November 2021
Abstract: This paper tends to evaluate the behavior of five- story RC building with and without floating columns using RC frames as lateral resisting system. This investigation had been carried-out using ETABS Ultimate V.18.1.1. The defined load cases, load combinations, the equivalent static lateral load pattern, and the response spectrum function were defined according ASCE7-16. The design criteria were set to be according to ACI 318-14. Eleven cases were proposed to investigate this behavior. One case was the building without floating columns. Nine cases were the building with different floating column schemes and the final case was the building with floating columns and another lateral resisting system (shear walls) for comparison purpose. Further comparisons of the results for all models are executed on the basis of parameters such as, story displacement, story drift, story stiffness, and response spectrum modal period. The results showed that, although the floating columns play an important role in architectural divisions or in multi-use buildings, but it affected the stiffness of the building negatively that led to increasing of the story lateral displacement and drift, also it led to increasing of modal time period. This mostly led to using a more stiffness lateral resisting system and eventually increasing the building’s structural costs.
Abstract: This paper tends to evaluate the behavior of five- story RC building with and without floating columns using RC frames as lateral resisting system. This investigation had been carried-out using ETABS Ultimate V.18.1.1. The defined load cases, load combinations, the equivalent static lateral load pattern, and the response spectrum function were defi...
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Project-Level Safety Management Framework for Semiconductor Project
Lan Zhang,
Thomas Zhang,
Junhui Heng
Issue:
Volume 9, Issue 6, November 2021
Pages:
186-193
Received:
20 October 2021
Accepted:
5 November 2021
Published:
12 November 2021
Abstract: Safety is one of the greatest challenges in the construction industry. Researchers proposed various safety systems to manage site safety and improve safety performance at the project level. However, these safety systems still exhibit large disconnections between the theoretical components of the systems, luck the risk prevention from specific work procedure and controlling methods. As a result, different safety teams often implement safety plans and activities in different ways, yielding different results without stability of the safety system. A safety framework that based on the construction method statement with a clear logic of safety management elements under controlling points is proposed to increase the efficiency of safety system execution at the project level to reduce the safety risks systematically. This study begins by analysing safety systems currently on the market and breaks them down to three main components: setting up the framework through systematic models, interconnecting various safety elements through safety management theories with logic, and controlling safety management data flow through an artificial neural network model, where corporate safety management frameworks are incorporated at the project level. Then the framework is further applied and tested in a semiconductor project. This framework provides an integration of safety elements, field activities and associated risks, draft the path and flow of information data generated from the safety activities and controlling points of data which enable the field safety management system to be executed with new technology of cloud based algorithm at project levels. Because each project is different based on the construction methods and sequence, the framework only covers a certain depth in the construction process based on the assumption of construction sequence presented in the study. Nevertheless, each project requires a custom design framework to accommodate the special construction method and sequence which might be different from this study to increase construction safety performance.
Abstract: Safety is one of the greatest challenges in the construction industry. Researchers proposed various safety systems to manage site safety and improve safety performance at the project level. However, these safety systems still exhibit large disconnections between the theoretical components of the systems, luck the risk prevention from specific work ...
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Application of Genetic Algorithms to Optimization of Medium and Heavy Rotating Equipment Foundations
Nulu Reddeppa,
Bommireddy Jayarami Reddy,
Hanchate Sudarsana Rao
Issue:
Volume 9, Issue 6, November 2021
Pages:
194-212
Received:
18 October 2021
Accepted:
8 November 2021
Published:
17 November 2021
Abstract: Optimal structural design involves dealing with three main factors visibly cross-sectional properties of the members, topology and configuration and meeting the intended functional requirements. Most of the traditional optimization techniques are based on the mathematical programming techniques, which assume that the variables are continuous, but whereas the process of structural design is generally characterized by finite often large numbers of variables of discrete in nature. Genetic Algorithm is the technique which can be used efficiently for the design optimization of the structure with discrete variables. From the study on previous work done on GA’s application in civil engineering, it has been noticed that application of GA’s is not attempted in rotating machine foundations where there is scope for determining suitable optimum shape and member sizes to achieve a well-tuned foundation. Dynamic design of machine foundation involves broad criterion such as foundation natural frequency shall be away from the machine operating frequency and foundation displacement amplitudes shall be well within the specified allowable limits. The above criterion largely depends on design factors such as size of members, shape of the foundations, concrete grade and soil characters. Presently obtaining a best suitable solution meeting the frequency and amplitude criteria by varying above four design factors involves many manual trails. This involves lot of computer and human efforts to try various combinations to arrive at the solution. Considerable resources and time need to be spent on arriving a suitable solution. Yet the solution so arrived may not be an optimum solution. In this work, Genetic algorithms is applied for optimization of solution time and foundation volume for industrial medium and heavy rotating equipment foundations. Optimum solution is obtained with above variables by setting frequency as target criteria. The optimum solution obtained from Genetic Algorithms is further verified for its compliance to its intended functional parameters by means of finite element model study.
Abstract: Optimal structural design involves dealing with three main factors visibly cross-sectional properties of the members, topology and configuration and meeting the intended functional requirements. Most of the traditional optimization techniques are based on the mathematical programming techniques, which assume that the variables are continuous, but w...
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Search of Non-circular Slip Surface Based on Improved FOA
Shen Hong,
Yu Xiuling,
Wang Pengyi
Issue:
Volume 9, Issue 6, November 2021
Pages:
213-220
Received:
28 October 2021
Accepted:
23 November 2021
Published:
24 November 2021
Abstract: The determination of the most critical non-circular slip surface can be attributed to the optimization of complex non-linear multi-peak function due to its numerous control variables and large amount of calculation. It is a trend in recent years to apply intelligent optimization algorithm into slope stability analysis. Considering that the standard Fruit fly Optimization Algorithm (FOA) is prone to fall into local extremum, the improved Fruit fly Optimization Algorithm is obtained by incorporating the standard FOA with the simulated annealing idea. In order to improve the search efficiency, a fixed step size is adjusted to an adaptive step size, and a double tier search strategy is proposed to be applied: the potential non-circular slip surface is obtained from the outer layer, and the factor of safety along the potential slip surface is calculated step by step from the inner layer. The improved FOA is applied to a slope with weak interlayer. The feasibility, superiority and efficiency of the improved algorithm are proved by comparing its answers to the judges'. Different inter-slice force functions, various initial values of Fs and λ are assumed, and the results show that these parameters could hardly affect final solution for safety factor.
Abstract: The determination of the most critical non-circular slip surface can be attributed to the optimization of complex non-linear multi-peak function due to its numerous control variables and large amount of calculation. It is a trend in recent years to apply intelligent optimization algorithm into slope stability analysis. Considering that the standard...
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Success Factors of Mixed-Use Building Construction Project: A Case of Arada Sub-City, Addis Ababa
Kidanemariam Sileshi Gebretsadik,
Melkamu Tadesse Wazza
Issue:
Volume 9, Issue 6, November 2021
Pages:
221-235
Received:
13 October 2021
Accepted:
11 November 2021
Published:
31 December 2021
Abstract: The construction sectors project implementation is realized by which it undergoes many problems, difficulties and highly complicated process from inceptions to completion. Ethiopia’s construction projects are highly subjected to cost and schedule overrun and developing success factors as early as possible is a pressing issue. The objective of this paper is to determine the most significant success factors of mixed use building construction project using quantitative statistical method. Data collected from different respondents through questionaries’ analyzed using RII. Based on the RII result General Project management Related success factors becomes the leading than other success factor group. This group is more general and shared by all stakeholder and considered in each phase from initiation to the end. Followed by Environment, Client, Consultant and contractor related major success factor groups respectively. All the aggregated list of success factor has a significant factor for the success. Most important success factors are: Lessons learned from previous project, having qualified and specialized personnel, clearly defining project scope, Consistency of currency price & stability of national economy, Material and equipment availability, Conducting On-job research, Consultant commitment to ensure construction work. Identifying success factors with respect to each stakeholders and phases will benefit a lot to do their best at each stage of the project. Learning from previous work, having qualified and specialized personnel and defining scope clearly should have to be the core of project participant at each stage of construction project to accomplish successfully.
Abstract: The construction sectors project implementation is realized by which it undergoes many problems, difficulties and highly complicated process from inceptions to completion. Ethiopia’s construction projects are highly subjected to cost and schedule overrun and developing success factors as early as possible is a pressing issue. The objective of this ...
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