• Steel and Composite Structures
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• v.31 no.4
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• pp.329-340
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• 2019

An innovated type of the flat steel plate-lightweight aggregate concrete hollow composite slab was presented in this paper. This kind of the slab is composed of flat steel plate and the lightweight aggregate concrete slab, which were interfaced with a set of perfobond shear connectors (PBL shear connectors) with circular hollow structural sections (CHSS) and the shear stud connectors. Five specimens were tested under static monotonic loading. In the test, the influence of shear span/height ratios and arrangements of CHSS on bending capacity and flexural rigidity of the composite slabs were investigated. Based on the test results, the crack patterns, failure modes, the bending moment-curvature curves as well as the strains of the flat steel plate and the concrete were focused and analyzed. The test results showed that the flat steel plate was fully connected to the lightweight aggregate concrete slab and no obvious slippage was observed between the steel plate and the concrete, and the composite slabs performed well in terms of bending capacity, flexural rigidity and ductility. It was further shown that all of the specimens failed in bending failure mode regardless of the shear span/height ratios and the arrangement of CHSS. Moreover, the plane-section assumption was proved to be valid, and the calculated formulas for predicting the bending capacity and the flexural rigidity of the composite slabs were proposed on the basis of the experimental results.

• Proceedings of the Korea Concrete Institute Conference
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• 2001.11a
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• pp.971-976
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• 2001

Numerical studies were performed to investigate the seismic performance of Flat Plate System. For the numerical studies, a computer program for Finite Element analysis was developed. Parametric studies were performed to investigate variations of strength and ductility of flat plate with major parameters: gravity load, reinforcement ratio, thickness, column sizes. The numerical results provide a valuable insights on the behavior of flat plates. The comparison with the current design method shows that the current design methods for strength and ductility need to be improved in some aspects.

• Journal of Ocean Engineering and Technology
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• v.19 no.1 s.62
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• pp.33-38
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• 2005

It has been well documented that plate forming is one of the most important processes in shipbuilding. In the most shipyards, the line heating method is primarily used for plate forming. Since the heating process is carried out for the curved plate and not for the flat plate, a curvature effect on the final deformation must be considered in deriving the simplified prediction models for deformation. This paper investigates the effect of curvature along the heating line on the deformation of the plate. First of all, results of numerical analysis are compared with these of a line-heating test, to justify the elasto-plastic analysis procedure for the present study, which shows good agreement. Then, the present numerical procedure is applied to flat and curved plate models, to investigate the curvature effect on the heat transfer characteristics and deformation by line heating.

• Proceedings of the Korea Concrete Institute Conference
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• 2010.05a
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• pp.127-128
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• 2010

The purpose of this study is to evaluate the seismic performance of gravity-designed post tensioned (PT) flat plate frames with and without slab bottom reinforcement passing through the column. For the PT flat plate frames, the slab bottom reinforcement is often omitted since the requirement for the slab bottom reinforcement for PT flat plates is not clearly specified in ACI 318-08. This study evaluates the seismic performance of the model frames was evaluated by conducting nonlinear time history analysis. The seismic performance of PT flat plate frames is significantly improved by placing slab bottom reinforcement passing through the column.

• Magazine of the Korea Concrete Institute
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• v.20 no.2
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• pp.25-36
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• 2008

Seismic design of reinforced concrete flat plate structures is often complicated as it deals with three dimensionality and continuous spans, and mostly material complexity and reinforcement variation. A great degree of uncertainty in such structural and material properties is thus inherent in the RC flat plate systems, and hinders simplification of the design process in terms of slab flexure, unbalanced moment transfer at a slab-column connection, and punching shear. For these reasons, there have been substantial changes and updates in building codes relating to flat plates and slab-column connections over a handful of decades. Also, for the same reason, some of codes never have been revised. As a consequence of nonsimultaneous development of each provision, it tends to confuse structural engineers when using a mixture of all different US code provisions. In this paper, in the step-by-step logical order, seismic design of the RC flat plate systems is re-organized and clarified to make it easier to apply. Furthermore, recent changes or proposed changes are introduced, and are explained as to how it will apply in practice.

• Transactions of the Korean Society of Mechanical Engineers B
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• v.37 no.3
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• pp.285-292
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• 2013

The purpose of this research is to investigate how the boundary layer separation caused by a tripping wire installed in front of the flat plate affects the transition from laminar to turbulent flow, and consequently mass transfer. A naphthalene sublimation technique is used to measure the local mass transfer coefficients on the flat plate, and two boundary conditions for the developed and developing flow are considered to evaluate the effects of the flow boundary. The local mass transfer data for a flat plate with a tripping wire are compared with the data for a flat plate without a tripping wire. The variation trends of the local heat transfer coefficients for the plates with and without the tripping wire are similar to each other in the case of the developing flow, but are quite different for the developed flow. The average Sherwood number for the flat plate with a tripping wire is much higher than that without a tripping wire because of the boundary layer separation.

• Journal of Korean Society of Steel Construction
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• v.24 no.4
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• pp.423-433
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• 2012

This paper summarizes full-scale gravity-load test results on CFT column-to-RC flat plate connections reinforced with shearhead. CFT construction has many structural and constructional advantages over conventional steel and RC column construction and is gaining wide acceptance. Meanwhile the use of RC flat plate system in the basement and residential floors of tall buildings is often mandatory to reduce story height and enable rapid construction in domestic practice. Combining CFT column and flat plate floor is expected to result in further rapid construction. However, the issues related to connecting CFT column to RC flat plate have not been fully addressed yet. Several promising connecting schemes by using steel shearhead were proposed and tested in this study. Test results showed that the proposed connection can exhibit the punching shear strength higher than RC flat plate counterparts. An empirical formula that can reasonably predicts the punching shear strength of the proposed connection was also proposed.

• Land and Housing Review
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• v.4 no.4
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• pp.371-382
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• 2013

This study performs an experimental investigation to evaluate the behavior of RC flat plate interior joints specimens. Three 60 percent scale Flat Plate interior specimens assemblies representing a portion of a Flat Plate Apartment Structural System subjected to simulated seismic loading (unbalanced moments) under constant axial load were tested, including one specimens with ordinary shear reinforcement and two specimens with folded bend type shear reinforcement. Test results are shown that (1) the design code KBC 2009 is accurate estimate the behavior of specimens. (2) Two types shear reinforcement have a similar structural behavior, but construction work of rebar with folded bend type shear reinforcement is easier than that of ordinary shear reinforcement. (3) In moderate seismic region, RC Flat Plate interior joint with folded bend type shear reinforcement is apply to structural design of Flat Plate.

• Journal of the Earthquake Engineering Society of Korea
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• v.11 no.6
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• pp.23-32
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• 2007

This study developed an analytical model for predicting nonlinear behavior of PT flat plate frames having slab-column connections with and without slab bottom reinforcement passing through the column. The developed model can predict the failure sequence until punching failure occurs. For verifying the analytical model, the test results of PT flat plate slab-column connections were compared with the results of the analysis. Moreover, the results of static pushover test and shaking table test of 2 story PT flat plate frame were compared with analysis results. For evaluating seismic performance of PT flat plate frame, this study conducted nonlinear response history analysis of the 2 story PT flat plate frame with and without slab bottom reinforcement passing through the column under 1940 El Centro ground motion scaled to have pseudo spectral acceleration of 0.3, 0.5, and 0.7g at the fundamental period of the frame. This study observed that as ground motion is more intense, seismic demands for the frame having the connections without slab bottom reinforcement passing through the column are larger than those without slab bottom reinforcement.

• Journal of the Korean Solar Energy Society
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• v.30 no.6
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• pp.28-33
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• 2010

Solar collectors to be applied are mainly flat-plate or vacuum tube collector which is used for hot water supply of house because of low heat value and low temperature. There are a necessity to expand applicable scope of solar collector into the industrial process heat source and air conditioner for coping with renewable energy policy of government and industrial trend. This study is to analysis the performance of PTC solar collector of concentrating type and flat-plate of non-concentrating. For this, temperature difference and heating value as insolation of air outside is measured from these two collectors mounted on 2-axial solar tracking system. It is investigated that temperature profile obtained from PTC solar collector is uniform and collecting heat per unit area is 6.8kcal/$m^2$ min which is about 3 times with compare to flat-plate collector of 2kcal/$m^2$min. Also the amount of heat to be produced from PTC solar collector is 3 Mcal/$m^2$ which is about 2 times with compare to flat-plate collector of 1.5Mcal/$m^2$ as a result of operating these two collectors during one month. Therefore, it is obtained that heat collecting performance of PTC solar collector is superior to flat-plate.