• Wind and Structures
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• v.14 no.1
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• pp.1-14
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• 2011

Open frame structures, such as those commonly found in industrial process facilities, are often densely occupied with process related equipment. This paper presents a method for estimating wind loads for high-solidity open frame structures that differs from current approaches, which accumulate wind load contributions from various individual structure components. The method considers the structure as a porous block of arbitrary plan dimension that is subject to wind from any direction. The proposed method compares favorably with wind tunnel test results for similar structures. The possibility of defining an upper bound force coefficient is also discussed.

• Structural Engineering and Mechanics
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• v.3 no.6
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• pp.583-592
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• 1995

The concept of "Saturation Impulse" for rigid, perfectly plastic structures with finite-deflections subjected to dynamic loading was put forward by Zhao, Yu and Fang (1994a). This paper extends the concept of Saturation Impulse to the analysis of structures such as simply supported circular plates, simply supported and fully clamped square plates, and cylindrical shells subjected to rectangular pressure pulses in the medium load range. Both upper and lower bounds of nondimensional saturation impulses are presented.

• Journal of the korean Society of Automotive Engineers
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• v.15 no.3
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• pp.111-119
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• 1993

In this study, the transient impact structural stress analysis of tracked vehicle structures under recoil impact load is investigated. ANSYS, ABAQUS Code are used for modelling and analytical procedures. The highest maximum Tresca stress occurs on race ring portion and its stress level is (.sigma.$_{T}$)$_{max}$ =20-40kgf/m $m^{2}$. The second highest stress occurs on upper plate of chassis and down plate of turret. The maximum stress level increases with loading direction and elevation angle. The results from liner static load analysis are very much different with impact analysis. Therefore, the practical solutions of structures under impact load can be obtained by only nonlinear transient impact analysis. The impact stress analysis of the steel vehicle structures is conducted. The maximum stress level is less than (.sigma.$_T/)$_{max}$m $m^{2}$. So, the design concept of steel structures can be adapted for new alternatives.s.s.s..s.

• Tunnel and Underground Space
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• v.17 no.5
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• pp.381-388
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• 2007

The regular RC structures have been transformed into irregular RC structures by alternate load of RC structures during explosive demolition. Numerical simulation programs have contributed to a better understanding of large displacement collapse behavior during explosive demolition, but there remain a number of problems which need to be solved. In this study, the 1/5 scaled 1, 3 and 5 stories RC structures were designed and fabricated. To consider the collapse possibility of upper dead load, fabricated RC structures were demolished by means of felling method. To observe the collapse behavior of the RC structures during felling, displacement of X-direction (or horizontal), displacement of Z-direction (or vertical) md relative displacement angle from respective RC structures were analyzed. Finally explosive demolition on the scaled RC structures using felling method are carried out, collapse behavior by felling method is affected by upper dead load of scaled RC structures. Displacement of X and Z direction increases gradually to respective 67ms and 300ms after blasting. It is confirmed that initial collapse velocity due to alternate load has a higher 3 stories RC structures than 5 stories.

• Steel and Composite Structures
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• v.27 no.5
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• pp.623-632
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• 2018

Performance-Based Plastic Design (PBPD) method has been recently developed to evaluate the behavior of structures in different performance levels. The PBPD method utilizes a base shear force and a lateral load pattern that are estimated based on energy and yielding mechanism concepts. Using of current lateral force pattern results in weak structural members in upper stories of a structure so that the values of the story drift in these stories are larger than the target drift, particularly in high-rise buildings. Therefore, such distribution requires modifications to overcome this drawback. This paper proposes a modified lateral load pattern for steel Eccentrically Braced Frames (EBFs) based on parametric study. In order to achieve the modified load pattern, a group of 26 EBFs has been analyzed under a set of 20 earthquake ground motions. Additionally, results of nonlinear dynamic analyses of EBFs have been post-processed by nonlinear regression analysis in order to derive the new load pattern. To prove the efficiency of present study, three EBFs as examples were designed by modified pattern and current PBPD distribution. Inelastic dynamic analyses results showed that the story drifts using modified lateral load pattern were well within the target values in comparison with current pattern in PBPD, particularly where the effect of the height is significant. The modified load pattern reduces the possibility of underdesigning in upper levels and overdesigning in lower levels of the frames.

• Proceedings of the Computational Structural Engineering Institute Conference
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• 1991.04a
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• pp.72-78
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• 1991

An improved procedure for earthquake resistant design of multistory building structures is proposed in this study. The effect of gravity load on seismic response of structures is evaluated through nonlinear dynamic analyses of a single story example structure. The presence of gravity load tends to initiate plastic hinge formation in earlier stage of a strong earthquake. However, the effect of gravity load seems to disapper as ground motion is getting stronger. And one of shortcomings in current earthquake resistant codes is overestimation of gravity load effects when earthquake load is applied at the same time so that it may leads to less inelastic deformation or structural damage in upper stories, and inelastic deformation is increased in lower stories. Based on these observation, an improved procedure for earthquake resistant design is derived by reducing the factor for gravity load and inceasing that for seismic load. Structures designed by the proposed design procedure turned out to have increased safety and stability against strong earthquakes.

• Journal of architectural history
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• v.16 no.5
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• pp.55-66
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• 2007

Through analysing on construction cases of stupa built in A.D. 7,8th, I have researched about these : constructive methods of inner soil of stupa, spatial compositions, characteristics of structures, arrangements of inner soil and etc. And cases analysed are six ; Mireuksajiseoktap(stone pagoda of Mireuksa Temple site), Gameunsajisamcheumgseoktap(three storied stone pagoda of Gameunsa Temple site), Goseonsajisamcheungseoktap(three storied stone pagoda of Goseonsa Temple site), Wolseong nawolliocheungseoktap(five storied stone pagoda in Nawonri, Wolseong), Guksagokseoktap(three storied stone pagoda in Guksa valley), Giamgokseoktap(three storied stone pagoda in Giam valley). Additionally we researched about inner soil of Sacheonwangsaji tapji(basement of stone stupa site in Sacheonwang Temple site) to speculate on composition of Synthetically, the foundation could be divided as core space and outer space. ; the former as structural function and the latter as ornamental function. And the core area could be divided again as center column space and buffer space. The relationship between core spaces and its formation are as belows; First, according to the area of foundation and scale of stone pagoda, formations of core are differed. As the scale of stone pagoda goes bigger, and the area of foundation goes larger, the structure of stone pagoda comprised by center column type and layered-core which endure upper load independently. On the contrary, as the scale of stone pagoda goes smaller, and the area of foundation goes lesser, the structure of stone pagoda tend to use only center column to endure upper part. Second, spatial composition of core area is comprised as two spaces, one which endure upper load and buffer space which absorb side pressure and upper pressure. The buffer space tend to be used in case of those structures which could not endure side pressure or have lots of joint. In some cases, it was located below the cover stone of foundation and gained upper load. And in case that have not gained pressure from side stone, the buffer space are comprised by smalle stone or roof tile to get structural supplement.

• Journal of Korean Association for Spatial Structures
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• v.16 no.2
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• pp.89-96
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• 2016

Cable structures are lightweight structures of flexible type, cable members have only axial stiffness related to tension, they can carry neither bending nor compression. This study is the analysis of cable truss systems are composed of upper and low cables by connecting bracing cables, the structural principle is based on a tensegrity system by using bracing tension members, discontinuous compression members and continuous tension members. A hanging roof of cable truss system is too flexible against vertical loads, most cable members are stabilized by connecting the prestressed upper and lower cable by bracing cables. A cable truss roof system is formed by adding a set of cables with reverse curvature to the suspension cables. With the sets of cables having opposite curvature to each other, cable truss is able to carry vertical load in both upward and downward direction with equal effectiveness, and then a cable truss acts as load bearing elements by the assemble of ridge cables, valley cables and bracing cables. This paper will be shown the geometric non-linear analysis result of cable truss systems with various sag ratio for deflections and tensile forces, the analytical results are compared with the results of other researchers.

• Proceedings of the Korea Concrete Institute Conference
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• 2000.10a
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• pp.623-628
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• 2000

In this paper, the behavior for transfer girder of the upper-wall and lower-frame structures was studied by the nonlinear finite element analysis. It was analyzed and compared with the experimental results. Analysis results showed that failure modes were progressed by a initial diagonal crack in the shear span between the edges of the load and intermediate support plate. The nonlinear finite element analysis could predict deformation, principal stress, ultimate load and concrete crack. Also analysis results showed good agreement the test results.

• Journal of the Society of Naval Architects of Korea
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• v.56 no.3
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• pp.187-199
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• 2019

In the case of gas carriers and oil tankers, pipes are installed on the upper deck as a moving passage to load LPG, LNG, crude oil, etc. Pipes used for loading or unloading liquid cargo in cargo holds are connected to the hull through support structures. However, many cases of hull damage have been reported where the various equipment and support structures are installed on the upper deck. It is assumed that not only the structural discontinuity where the hull and the pipe support structure meet, but also action due to the pipe loads and the hull girder bending moment are simultaneously affected. This paper deals with the design and strength evaluation of the support structure of pipes and cables installed on the upper deck of commercial ships and offshore structures. For these supporting structures, design conditions and working loads were defined. The design procedure was established through the structure analysis on the method of determining the member dimensions. A series of finite element analysis was performed on the factors to be considered in the design and the effects were discussed. The accuracy and design periods of the strength evaluation was improved and reduced by application of the automation program in the finite element analysis. It is also expected that the design reliability of the shipyard is improved.