• Steel and Composite Structures
• /
• v.30 no.2
• /
• pp.109-121
• /
• 2019

This paper presents the second part of the modeling for the strap combined footings, this part shows a mathematical model for design of strap combined footings subject to axial load and moments in two directions to each column considering the soil real pressure acting on the contact surface of the footing for one and/or two property lines of sides opposite restricted, the pressure is presented in terms of an axial load, moment around the axis "X" and moment around the axis "Y" to each column, and the methodology is developed using the principle that the derived of the moment is the shear force. The first part shows the optimal contact surface for the strap combined footings to obtain the most economical dimensioning on the soil (optimal area). The classic model considers an axial load and a moment around the axis "X" (transverse axis) applied to each column, i.e., the resultant force from the applied loads is located on the axis "Y" (longitudinal axis), and its position must match with the geometric center of the footing, and when the axial load and moments in two directions are presented, the maximum pressure and uniform applied throughout the contact surface of the footing is considered the same. A numerical example is presented to obtain the design of strap combined footings subject to an axial load and moments in two directions applied to each column. The mathematical approach suggested in this paper produces results that have a tangible accuracy for all problems and it can also be used for rectangular and T-shaped combined footings.

• Steel and Composite Structures
• /
• v.5 no.5
• /
• pp.407-420
• /
• 2005

This study presents the strength of braced and unbraced cold-formed steel wall frames consisting of several wall studs acting as columns, top and bottom tracks, and bracing members. The strength and the buckling mode of steel wall frames were found to be different due to the change of bracing type. In addition, the spacing of wall studs is a crucial factor to the strength of steel wall frames. The comparisons were made between the test results and the predictions computed based on AISI Code. The related specifications do not clearly provides the effective length factors for the member of cold-formed steel frame under compression. This paper proposes effective length factors for the steel wall frames based on the test results. A theoretical model is also derived to obtain the modulus of elastic support provided by the bracing at mid-height of steel wall frames in this research.

• Structural Engineering and Mechanics
• /
• v.30 no.6
• /
• pp.651-664
• /
• 2008

The purpose of this study is to develop a rehabilitation technique for heavily earthquake damaged masonry buildings. A full scale one storey masonry building with window and door openings was manufactured and tested on the shock table by applying increased amplitude free vibration up to the point where heavy earthquake damage was observed. Damaged test building was rehabilitated with vertical and diagonal steel straps and then tested again. The effectiveness of improvements obtained by the rehabilitation technique was investigated. Steel straps improved the lateral strength and stiffness of masonry walls and limited the lateral displacement of building. Stability of the masonry walls were also improved by the steel straps. Steel straps reduced the natural period of the earthquake damaged masonry building and prevented the failure of the building at the same amplitude of free vibration.

• Transactions of the Korean Society of Mechanical Engineers A
• /
• v.35 no.12
• /
• pp.1543-1548
• /
• 2011

Structural analysis is performed to design anchor straps for a large-scale-liquefied-natural-gas (LNG) storage tank with corner protection and an inner tank by considering structural integrity. Anchor straps made of 9% nickel steel are attached to the inner tank, corner protection, and concrete raft to prevent the failure of the inner tank during both normal and emergency operating conditions. Two finite element (FE) models were analyzed in this study. One is a stand-alone model of the anchor strap, while the other is an extended model of the substructure of the anchor strap, inner tank, and corner protection. Three-dimensional shell elements are used to effectively assess the bending and axial behavior of structures. The Tresca stress values in each part of the two models are calculated for operation under five different load-condition cases: normal operation, leakage of the LNG, hydro test, and two earthquake conditions.

• Journal of the Earthquake Engineering Society of Korea
• /
• v.9 no.6 s.46
• /
• pp.31-39
• /
• 2005

The purpose of this study was to investigate the nonlinear behavior of a cold-formed steel (CFS) shear panel, which was composed of built-up columns and tension-only diagonal straps for bracing, when excited by earthquake motions. For the purpose, shaketable tests of a full-scale two-story cold-formed steel (CFS) shear panel were conducted. in the shear panel, the diagonal strap is a major lateral force resisting system, which is a very ductile member, and the columns, which are gravity resisting members, are fabricated by wooing studs, which can't develop their full flexural strength because they may buckle locally. The test results showed that the straps dissipate most of energy of the shear panel in a tension-only and pinched way and the columns dissipate it relatively smaller than the straps but they still contribute to overall dissipation. As a result of this study, investigating real nonlinear behavior of a structure in earthquakes is a very important process by shaketable tests even though it is simple.

• Journal of the Korea institute for structural maintenance and inspection
• /
• v.22 no.2
• /
• pp.43-50
• /
• 2018

In this study, to investigate the shear connection material for the composite of steel plate and bottom plate, design standards and research cases for shear connectors in various countries around the world were analyzed and shear tests were performed on the Push-out specimens with a shear connection, which transmits the horizontal shear force developed on the contact surface between the steel plate and the concrete slab due to various vertical loads acting on the bridge deck. Through Push-out tests of shear studs, of which FRP bar instead reinforcement is placed, the shear stud evaluation formula of the steel strap bottom plate was suggested. The suggested equation suggested in this study has the safety factor of approximately three times compared to allowable strength of highway bridge design criteria. In addition, compared to existing DIN standards and Viest assessment equation, the results showed similar values(approximately, 5% error).

• Journal of Conservation Science
• /
• v.26 no.4
• /
• pp.417-427
• /
• 2010

This study is to examine the manufacturing technique based on scientific investigation and analysis on Steel-Plated Jewel Beetle's Adornment gilt-bronze openwork remains excavated from No. 100 site at Hwango-dong Gyeongju. As a result of the investigation on the manufacturing revealed that riveting was adopted to connect gilt-bronze openwork plates and steel plates, followed by mercury amalgam plating method and carving of the patterns by means of the dotted line engraving technique. There were some traces on the surface of Jewel Beetle wings that show the use of pins for fixing, which seems to be the result of recycling or processing. The sectional analysis shows the high possibilities that varnishing with lacquer was adopted for wing adhesion, and it was confirmed that varnishing with lacquer was used on the strap pendant plate to prevent corrosion.