• Structural Engineering and Mechanics
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• v.50 no.1
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• pp.73-88
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• 2014

Vibration characteristics of columns are influenced by their axial loads. Numerous methods have been developed to quantify axial load and deformation in individual columns based on their natural frequencies. However, these methods cannot be applied to columns in a structural framing system as the natural frequency is a global parameter of the entire framing system. This paper presents an innovative method to quantify axial deformations of columns in a structural framing system using its vibration characteristics, incorporating the influence of load tributary areas, boundary conditions and load migration among the columns.

• Korean Membrane Journal
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• v.10 no.1
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• pp.39-45
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• 2008

Polyelectrolyte complex based on two anionic polysaccharides, composed of sodium alginate and carrageenan, were prepared by interacting with divalent calcium ions in solution. The effects of annealing on the structural deformation of polyelectrolyte complex and on their characteristics at removing water from a methanol mixture from the point of molecular sieve were investigated and discussed. The result showed that the structural deformation of the annealed polyelectrolyte complex has an effect on the free volume between these polymer chains and the chelate segments such a shrinking of the overall morphology, which act as a molecular sieve in the separation of methanol and water mixtures.

• Structural Engineering and Mechanics
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• v.6 no.1
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• pp.63-76
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• 1998

This paper presents dynamic responses of structures with sliding base which limits the translation of external loads from ground excitation. A discrete element model based on the discontinuous deformation analysis method is proposed to study this sliding boundary problem. The sliding base is simulated using sets of fictitious contact springs along the sliding interface. The set of contact spring is to translate friction force from ground to superstructure. Validity of the proposed model is examined by the closed-form solutions of an idealized mass-spring structural model subjected to harmonic ground excitation. This model is also applied to a problem of a three-story structural model subjected to the ground excitation of 1940 El Centro earthquake. Analyses of both sliding-base and fixed-base conditions are performed as comparisons. This study shows that using this model can simulate the dynamic response of a sliding structure with frictional cut-off quite accurately. Results reveal that lowering the frictional coefficient of the sliding joint will reduce the peak responses. The structure responses in little deformation, but it displaces at the end of excitation.

• Structural Engineering and Mechanics
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• v.6 no.2
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• pp.201-215
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• 1998

The structural behavior of reinforced concrete frame infilled with a masonry wall is investigated by the method of discontinuous deformation analysis (DDA). An interface element is developed and it is incorporated into DDA to analyze the continuous and discontinuous behavior of the masonry structure. The numerical results are compared with previous research and possess satisfactory agreement. Then the structural behavior and stress distribution of a reinforced concrete frame infilled with a masonry wall subjected to a horizontal force are studied. In addition, the justification of equivalent strut is assessed by the distribution of principal stresses. The results show that the behavior of the masonry structure is highly influenced by the failure of mortar. On the basis of the distribution of principal stress of the masonry wall in the reinforced concrete frame, the equivalent strut can be approximately substituted for the masonry wall without separation and opening. However, the application of equivalent strut to the masonry wall with separation and opening needs further study.

• Journal of the Korean earth science society
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• v.34 no.5
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• pp.381-392
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• 2013

Socheong island is a unique island containing Precambrian stromatolites in South Korea. Most of Socheong stromatolites are domes and columns, occurring as 10 cm to 1 m thick stromatolite beds. Lower parts of the stromatolite beds are predominantly composed of domes, but columns increase toward the upper level of stromatolite beds. In many of the stromatolite beds, inclined columns are easily identifiable, which is generally considered as a result of heliotropism. From general lithology, sedimentary structures, inclined angles and distributional pattern, and structural deformation of sedimentary rocks of Socheong island, the inclination of Socheong stromatolites could be better interpreted as a secondary structural deformation probably after formation of stromatolite columns, rather than as a result of heliotropism. However, at this moment, we do not clearly reject heliotropism interpretation for inclined columns of Socheong stromatolites. This is because the original position of stromatolite columns could have been lost if structural deformation had affected the whole sedimentary rocks of Socheong island.

• Korean Journal of Metals and Materials
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• v.46 no.9
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• pp.572-576
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• 2008

Elastostatic compression tests were carried out on amorphous alloys to evaluate their energy absorption capability during homogeneous deformation at room temperature. Experiments demonstrated that a compressive stress below the global yield imposed on amorphous alloys for extended periods causes homogeneous plastic strain associated with the irreversible structural disordering. During the disordering process, free volume was created, dissipating the externally applied strain energy and the rate of creation was found to converge to a saturated value. We evaluated the capability of energy absorption of amorphous alloys during homogeneous deformation using recent theories on the evolution of the structural state.

• Journal of the Korea Furniture Society
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• v.22 no.4
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• pp.323-329
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• 2011

In our country, domestic species can not be used as a structural member because we have not yet grading system. So, to utilize as a basic data of grading system, bending test and numerical modelling on structural member were conducted in this study. 35 of Douglas-fir, 2" ${\times}$ 6", span 2.4 m were tested for the bending properties, and Ansys software was used to analyze the numerical modelling on the structural members. The data of knots were inspected and applied in numerical modelling. To obtain the accuracy of analysis, nonlinear numerical analysis was carried out instead of linear numerical analysis. Ultimate load had a wide range from 4883N to 11,738 N, and maximum deformation also had a range from 26 mm to 68 mm. Average of ultimate load was 8,616 N, and that of maximum deformation was 48 mm. The distinctive features of failure types were simple tension type and cross-grain tension type. Ulitmate load and maximum deformation from numerical modelling were 7,504 N and 37 mm. The numerical modelling drawn by this study is available to all species, and reasonable prediction on the bending performance is possible with only some material properties.

• International Journal of High-Rise Buildings
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• v.9 no.4
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• pp.361-368
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• 2020

The authors developed a new type of steel slit shear wall (SSSW) having the function of structural condition assessment through visually inspecting the out-of-plane deformation of the designed tapered links subjected to lateral deformation. To facilitate its practical application, this paper studies how to design dimensions of the tapered links. Two parameters, the width-to-thickness ratio of the tapered links and steel yield stress, were studied. The performance of structural condition assessment was affected by both parameters with the width-to-thickness ratio being the controlling one. Through both numerical and experimental study, the designed width-to-thickness ratio of tapered links for different levels of structural condition assessment was established considering the effect of different steel grades used. In practice, the dimensions of tapered links can be determined following the design equation provided. Finally, a design procedure for the proposed SSSW system is provided.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2007.06a
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• pp.615-616
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• 2007

• International Journal of High-Rise Buildings
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• v.8 no.3
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• pp.177-183
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• 2019

This paper describes the structural design of a 212 m tall building currently under construction in the Tokiwabashi District Redevelopment Project facing Tokyo Station. In this project there was a requirement to rationally solve many issues arising from the conditions of the redevelopment project. In particular, the following two points were considered to be important from the point of view of structural design. 1) To provide an overhang frame with the perimeter columns on the lower stories inclined, in order to enable a typical floor area that greatly exceeded the limitations of the underground structure shape. 2) To provide high grade seismic performance for the office buildings to be constructed on prime city center land. LSCVCS (Lower Stories Concentrated Vibration Control System) was proposed as the method of rationally designing the overhang frame, which is an extremely disadvantageous element in the structural scheme of the tall building with a large slenderness ratio. LSCVCS is a system to provide effective damping by arranging vibration control devices in a concentrated manner in a lower story with large story height, that produces large deformation in an earthquake. Also, the vibration control devices arranged in the lower story are limited to viscous devices, to take into consideration the residual deformation of the overhang frame after an earthquake. The results of investigations into the specific effects of the system for the seismic design are reported, including Performance-based seismic design.