• Journal of Korean Association for Spatial Structures
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• v.10 no.4
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• pp.67-74
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• 2010

Single layer latticed domes which have a mechanics property, a functional property, a aesthetic property and so on, occupies one part of long span space structures and after this, the using parts will be extended. The frame network pattern of single-layer latticed domes can be infinitely taken into account. The typical network patterns are triangular, square, hexagon, lamella and rib etc. It would take long time and cost too much to erect large roof structures with traditional erection techniques due to require of large number of temporary bracing and supports. The erection of large roof structures requires special techniques. As one of these special techniques is the Step-Up election method that utilizes jack-up supports and this will extremely saves time and cost to erect large roof structures. The objective of this study is to analysis the buckling characteristics of single-layer lamella domes according to the support number and position. From the result of this study, we obtained the fundamental data for the structural engineers who design the temporary support of large roof structures.

• Journal of the Society of Naval Architects of Korea
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• v.59 no.1
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• pp.39-45
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• 2022

Normal strategy of structure optimization procedure has been minimum cost or weight design. Minimum weight design satisfying an allowable stress has been used for the ship and offshore structure, but minimum cost design could be used for the case of high human cost. Natural frequency analysis and forced vibration one have been used for the strength estimation of marine structures. For the case of high precision experiment facilities in marine field, the structure has normally enough margin in allowable stress aspect and sometimes needs high natural frequency of structure to obtain very high precise experiment results. It is not easy to obtain a structure design with high natural frequency, since the natural frequency depend on the stiffness to mass ratio of the structure and increase of structural stiffness ordinary accompanies the increase of mass. It is further difficult at the grillage structure design using the profiles, because the properties of profiles are not continuous but discrete, and resource of profiles are limited at the design of grillage structure. In this paper, the grillage structure design system under the constraint of high natural frequency is introduced. The design system adopted genetic algorithm to realize optimization procedure and can be used at the design of the experimental facilities of marine field such as a towing carriage, PMM, test frame, measuring frame and rotating arm.

• Journal of the Society of Naval Architects of Korea
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• v.44 no.6
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• pp.605-611
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• 2007

A ship is composed of many grillage structures especially the deck which is consists of primary girders, transverse and longitudinal members. Several holes are arranged on these primary members for pipes, vents, etc. which cause stress concentration due to the discontinuity of the member. It is not easy to get the stress values around all these holes because of the huge amount of time necessary for computations. In this paper, a simple method to compute for the stress around the holes is suggested. This method is composed of two steps which are grillage analysis for primary members and detailed stress analysis using the results of the grillage analysis. This method is made for the design of the primary members with openings supporting the deck structure.

• Journal of the Computational Structural Engineering Institute of Korea
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• v.26 no.4
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• pp.263-269
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• 2013

In this study, the strain based monitoring method to evaluate the lateral structural response of buildings is presented and an applicability of the proposed method is confirmed through the numerical study. It is assumed that the fiber Bragg grating(FBG) strain sensor is employed to measure the strain response of members due to the excellent properties such as multiplexing, and higher sampling frequency. These properties of FBG sensors is proper for buildings the a lot of sensors are required to monitor the reponses of those. FBG sensors measure the strain response of vertical members and are employed to calculate the curvatures of members using the measured strain responses. Then the lateral displacement, and lateral acceleration is evaluated based on the curvatures of vertical members. Additionally, these dynamic responses of buildings are used to evaluate the dynamic properties of buildings such as the natural frequencies and mode shapes using the frequency domain decomposition(FDD) method. Through the application of nine-story steel moment frame example structure, it is confirmed that the proposed method is appropriate to evaluate the lateral structural responses and dynamic properties of buildings.