Enhancement of Mechanical Property of Concrete Structure Using the Macro and Micro Steel Fibers
Hyeok Jung Kim,
Nam Wook Kim
Issue:
Volume 8, Issue 1, January 2020
Pages:
1-9
Received:
7 January 2020
Accepted:
27 January 2020
Published:
18 February 2020
Abstract: Hybrid fiber reinforcement with both macro and micro steel fibers in the concrete matrix is applied in order to evaluate its effectiveness for crack arresting. One of the main objectives of this research is to establish a crack-free high performance concrete. In severe conditions, which may require high water tightness, such as a storage structure for low-level radioactive waste, crack-free high performance concrete structures could be applied. Hybrid fiber reinforcement is well known because it can show excellent performance with a suitable combination of fibers. In this study which deals with hybrid fiber reinforced concrete made with different fiber lengths and fiber contents, the factors which quantify crack resistance of concrete, mainly the first crack strength, flexural strength and strain energy release rate are examined. In this research, the crack resistance of concrete was investigated using the notched specimen by the 4-point bending test for the fiber reinforced concrete and hybrid fiber reinforced concrete (adding the macro and micro fibers). The general conclusions obtained are as follows. To the investigation of the crack resistance of concrete, we obtained the new theoretical equation of the critical strain energy release rate for the hybrid fiber reinforced concrete, and a deep correlation between experimental value and theoretical value was shown. Though in this research, total fiber contents 2.5% showed the maximum values in the strength and crack resistance, an investigation of the totally mechanical behavior needs more widely range of experiment.
Abstract: Hybrid fiber reinforcement with both macro and micro steel fibers in the concrete matrix is applied in order to evaluate its effectiveness for crack arresting. One of the main objectives of this research is to establish a crack-free high performance concrete. In severe conditions, which may require high water tightness, such as a storage structure ...
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Hybrid Simulation Framework for Multi-hazard Testing
Elias Strepelias,
Nikolaos Stathas,
Xenofon Palios,
Stathis Bousias
Issue:
Volume 8, Issue 1, January 2020
Pages:
10-19
Received:
22 January 2020
Accepted:
12 February 2020
Published:
2 March 2020
Abstract: The design of complicated structures which, under accidental actions, have to fulfill a certain performance level, has been a scientific challenge with social and economic implications, particularly in the field of earthquake engineering. Experimental testing on structures would shed light to the deriving issues, however the full-scaling requirements of the specimens and the most out of date existing laboratory facilities do not facilitate it. For that reason, it is generally proposed the testing structure to be decomposed in its components and the part of scientific interest can be laboratory tested, whereas the other substructures are analytically modelled. That approach is known as hybrid simulation method (HS) and lends itself as an efficient tool in unveiling the nonlinear response of structural systems, especially when testing in full-scale is sought. The present research aims to evaluate the technical aspects of implementing a robust, advanced hybrid simulation (HS) platform, based on technological advancements and combining user friendliness and effectiveness. In addition, the capabilities of the advanced platform pave the way to future research extensions towards studying multi-physics problems beyond the field of earthquake engineering. The good performance of the updated hardware configuration of the new platform was evaluated via a series of verification tests on a pinned steel cantilever column subjected to lateral loading in its elastic and inelastic response region and finally, making use of the advanced application platform as a whole, a hybrid simulation test was carried out on an industrial piping system under earthquake excitation.
Abstract: The design of complicated structures which, under accidental actions, have to fulfill a certain performance level, has been a scientific challenge with social and economic implications, particularly in the field of earthquake engineering. Experimental testing on structures would shed light to the deriving issues, however the full-scaling requiremen...
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