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Seismic Performance Analysis of RCC Multi-Storied Buildings with Plan Irregularity
Mohaiminul Haque,
Sourav Ray,
Amit Chakraborty,
Mohammad Elias,
Iftekharul Alam
Issue:
Volume 4, Issue 3, May 2016
Pages:
68-73
Received:
20 March 2016
Accepted:
28 March 2016
Published:
21 April 2016
Abstract: Bangladesh is one of the most earthquake prone areas in South-Asia and Sylhet is the most seismic vulnerable region in Bangladesh. Seismic performance analysis is highly recommended to ensure safe and sound building structures for this region. To get better performance from reinforced concrete (RCC) structure, new seismic design provisions require structural engineers to perform both static and dynamic analysis for the design of structures. The objective of the this study is to carry out static and dynamic analysis i.e. equivalent static analysis, response spectrum analysis (RSA) and time history analysis (THA) over different regular and irregular shaped RCC building frame considering the equal span of each frame as per Bangladesh National Building Code (BNBC)- 2006. In this study, four different shaped (W-shape, L-shape, Rectangle, Square) ten storied RCC building frames are analysed using ETABS v9.7.1 and SAP 2000 v14.0.0 for seismic zone 3 (Sylhet) in Bangladesh. Comparative study on the maximum displacement of different shaped buildings due to static loading and dynamic response spectrum has been explored. From the analyzed results it has been found that, for static load analysis, effects of earthquake force approximately same to all models except model-1(W-shape).W-shape has been found most vulnerable for earthquake load case. It is also found from the response spectrum analysis that the displacements for irregular shaped building frames are more than that of regular shaped building. The overall performance of regular structures is found better than irregular structures.
Abstract: Bangladesh is one of the most earthquake prone areas in South-Asia and Sylhet is the most seismic vulnerable region in Bangladesh. Seismic performance analysis is highly recommended to ensure safe and sound building structures for this region. To get better performance from reinforced concrete (RCC) structure, new seismic design provisions require ...
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Exploring the Potential of Alternative Pozzolona Cement for the Northern Savannah Ecological Zone in Ghana
Issue:
Volume 4, Issue 3, May 2016
Pages:
74-79
Received:
25 March 2016
Accepted:
5 April 2016
Published:
26 April 2016
Abstract: This project evaluates the performance of pozzolana cement elements produced from alternative raw materials with a view using them in low-cost housing. It also seeks the reduction of waste from agricultural sources and the cost of sandcrete blocks by using locally available materials. The need to find alternative materials to replace existing conventional ones has necessitated research into substitutes to cement with a view to investigating their usefulness to wholly or partly substitute ordinary Portland cement in the production of sandcrete blocks. This project investigates the possible use of Corn Cob Ash (CCA) as a partial replacement of cement in sandcrete block production. 140 no. 450mmx150mm×225mm solid sandcrete blocks of mix ratio 1:8 were cast, cured and crushed at 7, 14, 21, and 28 days. The corn cob ash was replaced at 0 to 40 percent levels at 5% intervals. The maximum compressive strength of 2.10 N/mm2 was recorded at 30% replacement on the 28th day. After 12 months of exposure under northern savannah climatic conditions, the compressive strength remained stable or even increased with the weathering exposure. The maximum value of 2.10N/mm2 for the 30% replacement level is found suitable and recommended for building construction having attained a 28-day compressive strength of more than 2.0N/mm2 as required by the National Building Code for non load bearing walls.
Abstract: This project evaluates the performance of pozzolana cement elements produced from alternative raw materials with a view using them in low-cost housing. It also seeks the reduction of waste from agricultural sources and the cost of sandcrete blocks by using locally available materials. The need to find alternative materials to replace existing conve...
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Effects on Environment and Health by Garments Factory Waste in Narayanganj City, Dhaka
Issue:
Volume 4, Issue 3, May 2016
Pages:
80-83
Received:
22 March 2016
Accepted:
5 April 2016
Published:
27 April 2016
Abstract: Bangladesh has more reputation for Readymade Garments in the world and which plays a significant role in the economical enhancement as well. Most of the garments factories in Bangladesh are located at Gazipur and Narayanganj industrial area, Dhaka. But in terms of pollution, the garments factory has been disgraced as being one of the world's most perpetrators. Now a day’s environmental problems are completely anchored in our ways of life. The main goal of this study is to find out the environmental and social problems which arise from garments waste of Narayanganj city and propose some ways of mitigation measures. This is done by analyzing and observing numerous data acquired from field survey. The field surveys were conducted among 100 general people near the study area, some VIP’s and some NGO’s. Findings from this study are that, the waste management systems are progressing very softly. So the garments factory need to improve the waste management system immediately and NGO side to help to raise the environmental condition.
Abstract: Bangladesh has more reputation for Readymade Garments in the world and which plays a significant role in the economical enhancement as well. Most of the garments factories in Bangladesh are located at Gazipur and Narayanganj industrial area, Dhaka. But in terms of pollution, the garments factory has been disgraced as being one of the world's most p...
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Premature Failure of Apedwa-Bunsu Junction Section of N6 in Ghana: Some Notes for Consideration
Yaw Adubofour Tuffour,
Nana Kwesi Agyepong,
Daniel Atuah Obeng
Issue:
Volume 4, Issue 3, May 2016
Pages:
84-91
Received:
13 April 2016
Accepted:
25 April 2016
Published:
11 May 2016
Abstract: This study investigated premature and continual failure of the Apedwa-Bunsu Junction section of Route N6 in Ghana despite an earlier maintenance intervention which included geotextile installation and placement of a new wearing course. It involved a condition survey, density, asphalt content, gradation, stiffness modulus and Falling Weight Deflectometer (FWD) tests on the section. The condition survey revealed cracking (alligator, transverse and longitudinal), ravelling, potholes, rutting and shoving as the predominant defects on the road. The density tests on the bituminous layers revealed relative compaction levels which, in most cases, did not meet the minimum required by the technical specifications despite the additional densification by traffic. The poor compaction was corroborated by high pavement deflections from the FWD device. Asphalt cores revealed a friable dense bituminous macadam (DBM) layer although bitumen extraction tests indicated all design asphalt contents were met. Lack of inter-particle cohesion within the DBM layer was suggestive of stripping damage to the asphalt concrete. Some samples of the crushed rock base contained plastic fines and fines content that exceeded specification limits. High stiffness modulus values of the bituminous layers suggested possible premature aging of the asphalt binder which probably accelerated crack development. An earlier intervention in the form of placement of geotextile in the wearing course failed to arrest cracking because the material had been placed at a shallow depth rendering it ineffective. It was concluded that inadequate compaction of the bituminous layers and the use of crushed rock and other pavement materials that did not wholly meet the technical specifications were the root causes of the premature failure of the section.
Abstract: This study investigated premature and continual failure of the Apedwa-Bunsu Junction section of Route N6 in Ghana despite an earlier maintenance intervention which included geotextile installation and placement of a new wearing course. It involved a condition survey, density, asphalt content, gradation, stiffness modulus and Falling Weight Deflecto...
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Research on Evaluation System of Vibration Induced by Shield Construction
Tao Lianjin,
Guo Fei,
Wang Guofeng,
Huang Jun,
An Junhai,
Liu Chunxiao,
Bian Jin
Issue:
Volume 4, Issue 3, May 2016
Pages:
92-97
Received:
21 May 2016
Published:
24 May 2016
Abstract: The research of vibration induced by rail transit should not only consider operation stages, but also extend to the construction phase. Based on the calculation results of site test, the evaluation index system was proposed which is suitable for vibration induced by shield construction. The evaluation indexes were built for the first time and the weight coefficient method was used to determine the weight of each evaluation index. According to actual application of evaluation project, the vibration level was described by Fuzzy language, then the evaluation index system of vibration induced by shield construction was established, which is verified by a project example. The research result shows that: the vibration induced by shield construction can be directly present by the evaluation indexes assessment system which was based on site test, so the leading factors can be effectively traced. Afterwards, a reasonable level of vibration and corresponding risk control measures can be gotten, then the satisfactory assessment result was obtained at last. The evaluation index system of vibration induced by shield construction provides some reference datum for the vibration sensitive area by shield construction.
Abstract: The research of vibration induced by rail transit should not only consider operation stages, but also extend to the construction phase. Based on the calculation results of site test, the evaluation index system was proposed which is suitable for vibration induced by shield construction. The evaluation indexes were built for the first time and the w...
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Study on Strategies of Energy Saving and Emission Reducing Building Design in Urban and Rural Areas
Issue:
Volume 4, Issue 3, May 2016
Pages:
98-103
Received:
21 May 2016
Published:
24 May 2016
Abstract: In China, huge building energy consumption is the most prominent problem in the current situation of energy consumption. It has caused a series of energy and environmental problems. Therefore, it is extremely urgent and significant to study energy saving and emission reducing strategies in the aspects of building orientation, separation distance, solar radiation, wind direction, internal and external environment, etc. This paper discusses current situation and development trends of building design on energy saving and emission reduction in urban and rural areas of China. Through discovering existing problems in building energy consumption and architectural design in China, this paper proposes strategies of energy saving and emission reduction in architectural design and analyzes specific measures in architectural design through the typical case study.
Abstract: In China, huge building energy consumption is the most prominent problem in the current situation of energy consumption. It has caused a series of energy and environmental problems. Therefore, it is extremely urgent and significant to study energy saving and emission reducing strategies in the aspects of building orientation, separation distance, s...
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Deterioration and Service Life Prediction of Concrete Subjected to Freeze–Thaw Cycles in Na2SO4 Solution
Guo Li,
Dan Wang,
Jian-Min Du
Issue:
Volume 4, Issue 3, May 2016
Pages:
104-110
Received:
21 May 2016
Published:
24 May 2016
Abstract: To investigate the resistance of normal concrete to sulfate solution frost, concrete specimens with different water/cement (w/c) ratios, mineral admixture types, replacement ratios, and air contents were fabricated. Then, these specimens were frozen and thawed cyclically in 5% concentration Na2SO4 solution. As the freezing and thawing cycles proceeding, the appearance morphology, mass loss, and dynamic elastic modulus (DEM) of the specimens were observed. The service life of concrete that is subjected to the freeze–thaw cycles in Na2SO4 solution was calculated based on specimens' DEM losses. Results indicated that the appearance damage and mass loss of concrete along with the freeze–thaw cycles were unnoticeable until failure, and DEM losses played a controlling role in determining specimens' failure. In addition, a sudden fracture failure in the middle occurred easily in specimens with low w/c ratio. Decreasing concrete w/c ratio can slightly increase the concrete resistance to the freeze–thaw cycles in Na2SO4 solution, whereas incorporating fly ash or slag has almost no effect. Moreover, higher replacement ratio of fly ash or slag increases the adverse effects on concrete. Adding an air-entraining agent to concrete can significantly improve its resistance to the freeze–thaw cycles. Air content at 4.6% and 5.7% can extend the service life of concrete under the freeze–thaw cycles in Na2SO4 solution by more than 5 times its ordinary life span.
Abstract: To investigate the resistance of normal concrete to sulfate solution frost, concrete specimens with different water/cement (w/c) ratios, mineral admixture types, replacement ratios, and air contents were fabricated. Then, these specimens were frozen and thawed cyclically in 5% concentration Na2SO4 solution. As the freezing and thawing cycles procee...
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Application of Progressive Collapse Analysis in a High-Rise Frame-Core Tube Structure
Hu Kai,
Qi Sanlin,
Qu Ge,
Jiang Li,
Lu Zheng,
Yang Shengsheng
Issue:
Volume 4, Issue 3, May 2016
Pages:
111-116
Received:
21 May 2016
Published:
24 May 2016
Abstract: Frame-core tube structure system is commonly adopted in high-rise office buildings and landmarks, which will cause a large range of damage and serious loss of life and property once the progressive collapse occurs. To analysis the progressive collapse resistance of a high-rise frame-core tube practical project, numerical simulation analysis based on alternate path method and explicit dynamics theory was conducted to study the dynamic response of the remain structure after removing a key member. In addition, large-scaled tests for the frame-core tube structure under static and dynamic loads were carried out to study the behavior and damage situation of the structure. The numerical simulation and test results proved that progressive collapse would not occur when local damages occurred in the bottom corner column, and the structure still has a good seismic performance under dynamic actions. And the feasibility and reliability of the selected numerical simulation method of progressive collapse analysis is proved according to the test results.
Abstract: Frame-core tube structure system is commonly adopted in high-rise office buildings and landmarks, which will cause a large range of damage and serious loss of life and property once the progressive collapse occurs. To analysis the progressive collapse resistance of a high-rise frame-core tube practical project, numerical simulation analysis based o...
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