• Proceedings of the Korea Concrete Institute Conference
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• 2006.05a
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• pp.306-309
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• 2006

The fully embedded composite truss beam is developed based on composite member, truss system before composite and beam system after composite. The proper design concept and method of the fully embedded composite truss beam are discussed. A bending test on the fully embedded composite truss beam with span length 25.0m is carried out to investigate the flexural behavior and ultimate strength of the developed structure up to failure. A good agreement between the measured and predicted results are observed.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.20 no.9
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• pp.2854-2865
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• 1996

The concept of variable-geometry truss structure(VGTS) is introduced as a class of actively controlled adaptive structure. VGTS can purposefully vary its geometric configurations by changing the lengths of some members of the structure. General kinematics and inverse kinematics of a statically determinate VGTS(variable geometry truss structure) are studied. The solution technique is based on the Jacobian matrix obtained via joint equilibrium equations. Pseudoinverse control method is applied to resolve the redundancy of a large VGTS. two types of actuator layout of octahedral type VGTS, VG truss and Stewart platform, are compared. Introducing the concept of performance index, Stewart platform based layout was found to has less consumption energy and manipulation time. A functional VGTS model with 3 octahedral modules is designed and manufactured for the labaratory demonstration. Six vertically located length-variable members are used to create general 6 d.o.f. motions.

• Steel and Composite Structures
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• v.52 no.1
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• pp.77-87
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• 2024

Analytical methods for assessment of the out-of-plane buckling of unbraced top chords of truss bridges may look obsolete while comparing them to finite element analysis. However they are, usually, superior when rapid assessment is necessary. Analytical methods consider the top chord as a bar on elastic supports provided by bracing (Holt, Timoshenko). Correct assessment of the support elasticity (stiffness) is crucial. In the case of truss bridge spans of traditional structural layout (cross-beams at the truss chord nodes only), the elasticity may be set based on the analysis of the, so called, U-frame stiffness. Here the analyses consider the U-frame itself (a pair of verticals and a cross-beam) or the U-frame with adjacent diagonals or the pair of diagonals (in the absence of verticals) and the members of the bottom chord in the adjacent panels. For all the cases, the stability analysis of the chord as a bar in compression is necessary. Unfortunately, the method cannot be applied to contemporary truss bridges without verticals, that usually have independent cross-beam decks (the cross-beams attached to truss chords at their nodes and between them). This is the motivation for the analysis resulting in the method of setting the stiffness of the equivalent U-frame for the aforementioned truss bridges. Truss girders of both, gussetless and gusseted, joints are taken into account.

• Journal of the Computational Structural Engineering Institute of Korea
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• v.24 no.5
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• pp.481-489
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• 2011

In this paper presents new force method by using singular value decomposition. The existing force method has some advantages about analysis of truss structures such as it is easier basic concept than finite element method, which apply to analyze truss structures. However, this method has complex formulation for analysis. Therefore, in this study proposes new force method using singular value decomposition, which is both having easy basic concept and simple computation than existing force method. The proposed method is illustrated through numerical examples.

• Journal of Korean Association for Spatial Structures
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• v.18 no.2
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• pp.69-78
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• 2018

In current research, it was attempted a preliminary design and evaluation of non-uniform ultra high-strength concrete (UHSC) truss members. UHSC used here has the compressive strength of 180 MPa, the tensile strength of 8 to 20 MPa, and the tensile strain after cracks up to 2%. By the three-dimensional finite element stress analysis as well as strut-tie approach on concrete solid beams, the non-uniform truss shape of UHSC truss was designed with the architectural esthetic concept. In a series of examples, to compare with conventional concrete members, the proposed UHSC truss members have advantages in capabilities of the slender design with minimum weight with high performances under transverse loadings as well as the aesthetically non-uniform design for spatial structures.

• Journal of Ship and Ocean Technology
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• v.5 no.2
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• pp.14-26
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• 2001

This paper presents a novel design approach that could generate structural design alternatives having different topologies and then, select the optimum structure from them with simulataneously determining its optimum design variables related to geometry and the member size subjected to the multiple objective design environments. For this purpose, a specialized genetic algorithm, called StrGA_DeAl + MOGA, which can handle the design alternatives and multi-criteria problems very effectively, is developed for the optimal structural design. To validate the developed method, method, plain truss design problems are considered as illustrative example. To begin with, some possible topological of the truss structure are suggested based on the stability criterion that should be satisfied under the given loading condition. Then, with the consideration of the given multi-criteria, several different topology forms are selected as design alternatives for the second step of the conceptual design process. Based on the chosen topolgy of truss structures, the sizing or shaping optimization process starts to determine the optimum design parameters. Ten-bar truss problems are given in the paper to confirm the above concept and methodology.

• Computational Structural Engineering
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• v.10 no.3
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• pp.195-202
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• 1997

The charateristics of stabilization for stabilized truss unit-structures with cable and truss are investigated in this paper. This unit system is composed of a central post and eight cables, and is connected by hinge joints, and stabilized by self-equilibrated stress field. As this unit structure itself is a statically closed and stabilized system individually, it can be employed to assemble structures with various configurations. In this study, for stabilization of truss structures stabilized by cable tension, the structural concept of unit structures, the range of various geometrical parameters and the relationship of governing parameters about unit systems are explained.

• Journal of the Architectural Institute of Korea Structure & Construction
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• v.35 no.7
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• pp.147-156
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• 2019

The purpose of this study is to consider structural issues and analyze construction sequences when constructing hanging floors supported by Mega truss. Since suspended structures were supported by the Mega truss, vertical load on suspended structures was needed to transfer from low to high. Deflection management of structures was the primary point under construction. The results of this study were as follows; The steel structures, which has relatively lighter self-weight, were constructed upwards after the base floor steel truss erection. Concrete Placing, which has relatively heavier self-weight, were performed in two phases to minimize structure's deflection. Slab was placed downwards from the top floor to lower floor whereas column was places upwards. Deflection measurements were carried out at every construction sequences.

• Magazine of the Korea Concrete Institute
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• v.10 no.1
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• pp.10-19
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• 1998

• Coupled systems mechanics
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• v.9 no.1
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• pp.47-62
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• 2020

In this paper we study the control for nonlinear geometric instability problem of a deep or a shallow truss or yet a frame structure. All the structural models are built with geometrically exact truss and beam finite elements.The proposed models can successfully handle large overall motion under static or dynamic conservative load.The control strategy considers adding a damping from either friction device or viscous damper.This kind of control belong to well-known concept of passivity. Different examples are presented in order to illustrate the proposed theoretical developments.