Asian Transactions on Engineering

Volume: 02, Issue: 06, January 2013
ISSN 2221-4267

Title: Seismic Vulnerability Assessment of RC Structures: A Review
Author(s): Md Aftabur Rahman, Md Shajib Ullah
Paper ID: ATE-90214062
Pages: 1 - 6
Abstract: Earthquake induced damage has been increased over the last few years. Gujrat (2001), Sumatra (2004) & Haiti (2010) are burning example of devastating damage due to earthquake. The collapse of engineered and non-engineered buildings during an earthquake is the chief contributor to the loss of lives and injuries to people. A state-of-the-art review of the seismic vulnerability assessment of RC structures is presented in this paper. The review includes the history of vulnerability assessment, basic concept of vulnerability assessment, various screening procedure, development of screening techniques, advancement of technology etc. This paper also focuses on some recent vulnerability assessment techniques that would lead to identify buildings which might pose in case of an earthquake. Based on the scope, the future work on the topic is outlined.

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Title: Efficient New Numerical Technique for RC Structures with Construction Defects under Monotonic and Cyclic Loading Conditions
Author(s): Mostafa Fahim, Said Elkoly and Shreif Morad
Paper ID: ATE-30219063
Pages: 7 - 16
Abstract: Forms in concrete construction are vital as they provide the fresh concrete its shape and hold it until it hardens. Concrete compaction may not be required if self-compacting concrete (SCC) is the construction material used. After removal of the forms, concrete which is honeycombed should be repaired, or replaced, prior to the application of curing compound. But some contractors repair honeycombed concrete at the end of the construction. The consequences of doing so will affect the long-term properties of the honeycombed members and may be serious if the building is hit by an unexpected load such as earthquake during construction. In this study a finite element (FE) model is proposed and utilized in the analysis of reinforced concrete columns with honeycomb defects and subjected to gravity and horizontal loads. The FE program developed is based on the fiber beam-column element technique. The outcomes of the developed FE program were verified and compared to those of experimental test results in the literature. A parametric study was performed to investigate the effects of different parameters that may affect the lateral load resistance of RC-columns such as honeycomb location, size, depth and loading factor. The results show that the location and loading factor (applied vertical load) have significant influence on the lateral load resistance of the RC columns.

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Title: Calibration of machine tools by means of laser measuring systems
Author(s): S. Ekinovic, H. Prcanovic, and E. Begovic
Paper ID: ATE-90220060
Pages: 17 - 21
Abstract: The need for very precise measurements has emerged with evolution of automatic and CNC machine tools. Precision and accuracy are amongst main requests on modern machine tools. To define and know this characteristic of machine tools standard measuring procedures have been used for many years. Yet, others more advanced approaches and equipments, like laser measuring systems, are also available for measuring machine parameters like straightness of movements, repeatability, surfaces flatness, parallelism etc. This paper shows comparison of measuring results and measuring procedure between two different laser measuring systems, Damalini D525 and Renishaw ML10. Measurements are performed on DMU monoBlock60, CNC universal milling machine. Same type of measurements, straightness measurement of main shaft movement in Y direction, is performed simultaneously by means of both of the laser systems. Results presented in this paper shows that there are differences in between measuring results as well as in between measuring procedures for selected lasers. Hence, the correct choice of measuring device in that sense can save time and decrease costs of machine maintenance.

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Author(s): Muhammad Abdus Samad, MD. SaifulAlam, and NishatTusnim
Paper ID: ATE-80204066
Pages: 22 - 28
Abstract: Growth of business world these days created tighter market competition, because the existing industrial market become more global and have penetrated the inter-states boundary. In competition which progressively tightens like this, every company claimed to own the excellence and competitiveness so that probabilities to win the competition become greater. Those conditions forced manufacturing operations to continually striving to reduce lead time of their operations. Their goal is to satisfy the customer with the exact product, quality, quantity, and price in the shortest amount of time. It can only be achieved if the company is able to create and to implement effective and efficient processes in each of its line of their business. For this purpose lean tools are used because lean focus on the continuous improvement of a company towards the ideal through the relentless reduction of waste. Value Stream Mapping (VSM) is a Special type of flow chart that uses symbols known as "the language of Lean" to depict and improve the flow of inventory and information. Value Stream Mapping Purpose is to provide optimum value to the customer through a complete value creation process with minimum lead time. For this purpose we have tried to show how the lead time can be reduced by using lean tools properly. A trim manufacturing company was being selected for case study. In this case study we have studied production process of one product and draw the current state value stream map. From the current data analysis we found out the problems and gave some recommendations to improve the production lead time and provide a future state value stream map.

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