• Journal of the Korea Concrete Institute
• /
• v.20 no.1
• /
• pp.35-41
• /
• 2008

In general, flat plate systems have been used as a gravity load resisting system (GLRS) in building. Thus, this system should be constructed with lateral force resisting system (LFRS) such as shear walls and brace frames. GLRS should retain the ability to undergo the lateral drift associated with the LFRS without loss of gravity load carrying capacity. And flat plate system can be designed LFRS as ordinary moment frame with the special details. Thus, flat plate system designed as GLRS or LFRS should be considered internal forces (e.g., unbalanced moments) and lateral deformation generated in vicinity of slab joints render the system more susceptible to punching shear. ACI 318 (2005) allows the direct design method, equivalent frame method under gravity loads and allows the finite-element models, effective beam width models, and equivalent frame models under lateral loads. These analysis methods can produce widely different result, and each has advantage and disadvantages. Thus, it is sometimes difficult for a designer to select an appropriate analysis method and interpret the results for design purposes. This study is to help designer selecting analysis method for flat plate system and to verify practicality of the modified equivalent frame method under lateral loads. This study compared internal force and drift obtained from frame methods with those obtained from finite element method under gravity and lateral loads. For this purposes, 7 story building is considered. Also, the accuracy of these models is verified by comparing analysis results using frame methods with published experimental results of NRC slab.

• Smart Structures and Systems
• /
• v.5 no.6
• /
• pp.613-632
• /
• 2009

The present paper is concerned with the design of a proper patch actuator network in order to track a desired displacement of the sidewalls of a one-storey frame structure; both, for the static and the dynamic case. Weights for each patch of the actuator network found in our previous work were based on beam theory; in the present paper a refinement of these weights by modeling the sidewalls of the frame structure as thin plates is presented. For the sake of calculating the refined weights approximate solutions of the plate equations are calculated by an extended Galerkin method. The solutions based on the analytical plate model are compared with three-dimensional Finite Element results computed in the commercially available code ANSYS. The patch actuator network is put into practice by means of four piezoelectric patches attached to each of the two sidewalls of the frame structures, to which electric voltages proportional to the analytically refined patch weights are applied. Analytical and numerical results coincide very well over a broad frequency range.

• Journal of the Korea Concrete Institute
• /
• v.17 no.3 s.87
• /
• pp.419-426
• /
• 2005

This study is to propose a modified equivalent frame model for flat plate slabs under lateral loads. ACI 318 (2002) allows equivalent frame methods to conduct two-way slab system analysis subjected to gravity loads as well as lateral loads. Since the equivalent frame method in the ACI 318 (2002) has been developed base on the behavior of two-way system for gravity loads, and nay not predict the behavior of flat plate slabs under lateral loads with good precision. This study develops a modified equivalent frame model which can give more precise answer for flat plate slabs under lateral loads. This model reflects the actual force transfer mechanism among the components of flat plate slab system, which are slabs, columns and torsional members, more accurately under lateral loads than existing equivalent frame models. The accuracy of this model is verified by comparing the analysis results using the proposed model with the results of finite element analysis. The analysis results of other existing models are included in the comparison. For this purpose, 2 story building having 3 spans in both directions is considered. Analytical results show that the modified equivalent frame model produces comparable drift and slab internal moments with those obtained from finite element analysis.

• Computers and Concrete
• /
• v.20 no.6
• /
• pp.663-670
• /
• 2017

The post-tensioned (PT) flat plate slab system is commonly used in practice, and this simple and fast construction method is also considered to be a very efficient method because it can provide excellent deflection and crack control performance under a service load condition and consequently can be advantageous when applying to long-span structures. However, a detailed design guideline for evaluating the lateral behavior of the PT flat plate slab system is not available in current design codes. Thus, typical design methods used for conventional reinforced concrete (RC) flat plate slab structures have inevitably been adopted in practice for the lateral load design of PT flat plate structures. In the authors' previous studies, the unified equivalent frame method (UEFM) was proposed, which considers the combined effect of gravity and lateral loads for the lateral behavior analysis of RC flat plate slab structures. The aim of this study is to extend the concept of the UEFM to the lateral analysis of PT flat plate slab structures. In addition, the stiffness reduction factors of torsional members on interior and exterior equivalent frames were newly introduced considering the effect of post-tensioning. Test results of various PT flat plate slab-column connection specimens were collected from literature, and compared to the analysis results estimated by the extended UEFM.

• Journal of the Korean Wood Science and Technology
• /
• v.20 no.1
• /
• pp.46-50
• /
• 1992

본 연구는 잣나무 간벌재를 이용한 plywood gusset plate 접합과 toothed metal plate 접합에 대하여 인장력을 가해 조사하였다. plywood gusset plate 접합에 있어서는 합판과 부재 사이를 상온 경화제(초산 비닐 수지)로 접착한 후 6d 못으로 접합한 형태와 단지 합판만을 사용한 형태의 plywood gusset plate 접합 사이의 기계적 특성 차이를 조사했다. toothed metal plate 접합은 plywood gusset plate 접합보다 인장력에서 좋은 behavior를 보였다. 또한 접착제를 가한 plywood gusset plate 접합은 접합제를 가하지 않은 형태보다 큰 하중 지지력을 보였다.

• Journal of Fisheries and Marine Sciences Education
• /
• v.27 no.4
• /
• pp.973-980
• /
• 2015

This study was done to investigate the quality characteristics of salmon frame with citric acid pretreatment. Sliced salmon frame samples were cured in soy sauce, sugar, pepper, and sodium nitrate for 12 h and then dried at 3 h and then dried at $60^{\circ}C$ for 3 h. As the autoclaving at $130^{\circ}C$ for 15 min, the pH, moisture content, crude ash, crude fat, crude protein, acid value (AV), peroxide value (POV), volatile basic nitrogen (VBN), trimethylamine (TMA), total plate count and E. coli were measured at $4^{\circ}C$, $25^{\circ}C$ and $35^{\circ}C$ of storage days. The AV, POV, VBN, TMA and total plate count for all samples significantly increased as during storage days (p<0.05). All samples of storage, for autoclaving on salmon frame, there were no growth on E.coli. In the making of autoclaving on salmon frame, technologies for more safety from microbial growth should accompany pretreatment with citric acid.

• Journal of the Korean Society of Costume
• /
• v.59 no.3
• /
• pp.82-95
• /
• 2009

The kind and the use of the fabrics for crown manufacture in the Baekje period has been studied by characterizing the imprinted fabrics on the crowns and the diadem ornaments from the old tomb. The contact region with the skin inside of the crown and the region between the bark of white birch and the gilt bronze openwork plates contained fabrics. The fabrics used in the gilt-bronze crown were all plain weave silk except that of Yongwonri tomb where loosely woven thin tabby was used. There have been 4-types of iron framed diadem of the Baekje, which comprise the inverted triangle-shaped diadem only with iron frame, the diadem with gold plate ornament in the iron frame, the diadem decorated with mica plate and gold plate, and the diadem with silver ornament in the iron frame. The fabrics used in the triangle shaped iron frame diadem include plain weave silk, irregular plain woven silk, thin tabby, complex silk gauze, twill weave on plain ground, and warp-faced compound weave. The iron frames were wrapped with the fabrics from one layer up to three layers, and the iron diadem was covered with one later of loosely woven textile such as irregular plain woven silk, thin tabby, and complex silk gauze. But in case of decorating the iron diadem with gold Plate ornaments, multiple layers of fabric were used to sustain the weight of the ornaments. The fabrics in the iron diadem frame were sewed with running stitch, overedge stitch or hemming stitch, diagonal hemming stitch, half back stitch), and overcast stitch.

• Steel and Composite Structures
• /
• v.19 no.6
• /
• pp.1403-1419
• /
• 2015

When precast concrete infill panels are connected to steel frames at discrete locations, interaction at the structural interface is neither complete nor absent. The contribution of precast concrete infill panels to the lateral stiffness and strength of steel frames can be significant depending on the quality, quantity and location of the discrete interface connections. This paper presents preliminary experimental and finite element results of an investigation into the composite behaviour of a square steel frame with a precast concrete infill panel subject to lateral loading. The panel is connected at the corners to the ends of the top and bottom beams. The Frame-to-Panel-Connection, FPC4 between steel beam and concrete panel consists of two parts. A T-section with five achor bars welded to the top of the flange is cast in at the panel corner at a forty five degree angle. The triangularly shaped web of the T-section is reinforced against local buckling with a stiffener plate. The second part consists of a triangular gusset plate which is welded to the beam flange. Two bolts acting in shear connect the gusset plate to the web of the T-section. This way the connection can act in tension or compression. Experimental pull-out tests on individual connections allowed their load deflection characteristics to be established. A full scale experiment was performed on a one-storey one-bay 3 by 3 m infilled frame structure which was horizontally loaded at the top. With the characteristics of the frame-to-panel connections obtained from the experiments on individual connections, finite element analyses were performed on the infilled frame structures taking geometric and material non-linear behaviour of the structural components into account. The finite element model yields reasonably accurate results. This allows the model to be used for further parametric studies.

• Steel and Composite Structures
• /
• v.29 no.2
• /
• pp.231-242
• /
• 2018

As a lateral load resisting component, buckling restrained steel plate shear walls (BRW) have excellent energy dissipating capacity. Similar to thin steel plate shear walls, the mechanical behavior of BRWs depends on the boundary elements (adjacent beams and columns) which need adequate strength and stiffness to ensure the complete yielding of BRWs and the emergence of expected plastic collapse mechanism of frame. This paper presents a theoretical approach to estimate the design forces for boundary elements of beam-connected BRW (i.e., The BRW is only connected to beams at its top and bottom, without connections to columns) using a fundamental plastic collapse mechanism of frame, a force transferring model of beam-connected BRW and linear beam and column analysis. Furthermore, the design method of boundary beams and columns is presented. The proposed approach does not involve nonlinear analyses, which can be easily and efficiently used to estimate the design forces of beams and columns in a frame with BRWs. The predicted design forces of boundary elements are compared with those from nonlinear finite element analyses, and a good agreement is achieved.

• 한국태양에너지학회:학술대회논문집
• /
• 2009.04a
• /
• pp.61-65
• /
• 2009

Window integrated solar collector is to simply install inside of the existing double glass window frame. Double glass window frame is consist of inner glass of Low-E coating and Silver coating, and outer glass of low iron reinforced glass. In order to secure natural lighting in a room, only 50% of window frame is covered with solar collectors. Solar absorption or transmission rate varies seasonally depending on sun angles. Part of inner glass where right behind of the solar plate is covered with silver coating to increase absorption rate of solar plate. The collector is made of a copper serpentine where aluminum fins are soldering. To improve the effect of insulation of inside of the window frame is recommend vacuum. As a result, we are making the 3th sample and will archieve below $F_RU_L=7.5W/m^2^{\circ}C$ that is the account of heat lossed, and above $F_R({\tau}{\alpha})=0.45$.