scholarly journals Numerical Study on the Deformation Behavior of Longitudinal Plate-to-High-Strength Circular Hollow-Section X-Joints under Axial Load

2019 ◽  
Vol 9 (19) ◽  
pp. 3999
Author(s):  
Swoo-Heon Lee ◽  
Kyung-Jae Shin ◽  
So-Yeong Kim ◽  
Hee-Du Lee
Keyword(s):  
Yield Strength ◽  
High Strength Steel ◽  
Axial Load ◽  
Joint Strength ◽  
High Strength ◽  
Hollow Section ◽  
Strength Limit ◽  
Ultimate Deformation ◽  
Deformation Limit ◽  
Circular Hollow Section

This study aims to investigate the joint strength of longitudinal plate-to-high-strength steel circular hollow-section X-type joints under plate axial load. The material properties of high-strength steel with nominal yield strengths of 460, 650, 900, and 1100 MPa were used for parametric analysis. The variables for analysis were ratios of chord diameter to thickness, plate width to chord diameter, and utilization. To determine the capacity of connections, the joint strengths using a deformation limit and a strength limit were considered and compared with American Institute of Steel Construction (AISC), Eurocode 3, and ISO 14346. The joint strength determined by the ultimate deformation limit is approximately equal to the joint strength determined by the strength limit state at the yield strength of 460 MPa. The difference between both the joint strengths, however, becomes higher with increasing yield strength. The design equations estimate the joint strength based on the ultimate deformation limit approximately until the limitation of the nominal yield strength in each design code. As the nominal yield strength increases, the joint strengths are overestimated. In using high-strength steel in circular hollow-section X-type joints, the reduction factors of 0.75 and 0.62 for AISC and ISO 14346 are suggested for the nominal yield strengths of 900 and 1100 MPa, respectively. In Eurocode 3, the reduction factor of 0.67 is also suggested for a yield strength of 1100 MPa.

Behavior of plate-to-circular hollow section joints of 600 MPa high-strength steel

2012 ◽  
Vol 12 (4) ◽  
pp. 473-482 ◽  
Author(s):  
Swoo-Heon Lee ◽  
Kyung-Jae Shin ◽  
Hee-Du Lee ◽  
Woo-Bum Kim ◽  
Jae-Guen Yang
Keyword(s):  
High Strength Steel ◽  
High Strength ◽  
Hollow Section ◽  
Circular Hollow Section

INTERACTION STRENGTH FOR CHS-TO-LONGITUDINAL PLATE JOINTS UNDER AXIAL LOAD AND IN-PLANE BENDING MOMENT

2017 ◽  
Vol 4 (1) ◽  
Author(s):  
Hee-Du Lee ◽  
Swoo-Heon Lee ◽  
Da-Som Chu ◽  
Hye-Min Shin ◽  
Kyung-Jae Shin ◽  
...  
Keyword(s):  
Axial Load ◽  
Maximum Yield ◽  
Interaction Strength ◽  
Bending Moment ◽  
High Strength ◽  
Experimental Tests ◽  
Hollow Section ◽  
Plane Bending ◽  
Maximum Yield Strength ◽  
Circular Hollow Section

The circular hollow section (CHS) has lots of advantages in excellent structural properties, architecturally attractive features. Thus, CHSs are used extensively in many applications in buildings, bridges, towers, and offshore. In CHS, it is necessary to understand the various complex shape of CHS joint because loads act simultaneously according to joint type. The use of high-strength steel has been continuously increased, but the current design equation in AISC 2011 or KBC 2016 limits maximum yield strength 360 MPa. This paper studies an interaction strength of high-strength CHS-to-longitudinal plate X-joint subjected to combination of plate axial load and in-plane bending moment. For the study, numerical analysis based on experimental tests was carried out. The analysis was performed according to variables for determining shape of joint, i.e., chord slenderness, plate width-to-CHS diameter ratio, and utilization ratio. Investigations have shown that a linear summation of the ratios for axial load and in-plane bending moment may be used as conservative approximation.

High-Strength Steel Hot Forming Mechanics Performance and Characteristic Experimental Study

2016 ◽  
Vol 693 ◽  
pp. 800-806
Author(s):  
You Dan Guo
Keyword(s):  
Yield Strength ◽  
High Strength Steel ◽  
High Strength ◽  
High Energy ◽  
Absorption Capacity ◽  
Hot Forming ◽  
Gas Content ◽  
Strength Increase ◽  
Gradual Change ◽  
Forming Process

In high-strength steel hot forming, under the heating and quenching interaction, the material is oxidized and de-carbonized in the surface layer, forming a gradual change microstructure composed of ferrite, ferrite and martensite mixture and full martensite layers from surface to interior. The experiment enunciation: Form the table to ferrite, ferrite and martensite hybrid organization, completely martensite gradual change microstructure,and make the strength and rigidity of material one by one in order lower from inside to surface, ductility one by one in order increment in 22MnB5 for hot forming;Changes depends on the hot forming process temperature and the control of reheating furnace gas content protection, when oxygen levels of 5% protective gas, can better prevent oxidation and decarburization;Boron segregation in the grain boundary, solid solution strengthening, is a major cause of strength increase in ;The gradual change microstructure in outer big elongation properties, make the structure of the peak force is relatively flat, to reduce the peak impact force of structure, keep the structure of high energy absorption capacity;With lower temperature, the material yield strength rise rapidly,when the temperature is 650 °C, the yield strength at 950 °C was more than 3 times as much.

scholarly journals Research on Concrete Columns Reinforced with New Developed High-Strength Steel under Eccentric Loading

2019 ◽  
Author(s):  
Yonghui Hou ◽  
Shuangyin Cao ◽  
Xiangyong Ni ◽  
Yizhu Li
Keyword(s):  
Yield Strength ◽  
Bearing Capacity ◽  
High Strength Steel ◽  
High Strength ◽  
Concrete Columns ◽  
Lower Amount ◽  
Transverse Reinforcement ◽  
Longitudinal Reinforcement ◽  
Small Eccentricity ◽  
Failure Patterns

The use of new developed high-strength steel in concrete members can reduce steel bars congestion and construction costs. This research aims to study the behavior of concrete columns reinforced with new developed high-strength steel under eccentric loading. Ten reinforced concrete columns were fabricated and tested. The test variables are transverse reinforcement amount and yield strength, eccentricity, and longitudinal reinforcement yield strength. The failure patterns are compression and tensile failure for columns subjected to small eccentricity and large eccentricity, respectively. The same level of post-peak deformability and ductility only can be obtained with lower amount of transverse reinforcement when high-strength transverse reinforcements are used in columns subjected to small eccentricity. The high-strength longitudinal reinforcement can improve bearing capacity and post-peak deformability of concrete columns. Besides, three different equivalent rectangular stress block (ERSB) parameters in predicting bearing capacity of columns with high-strength steel were discussed based on test and simulated results. It is concluded that the Code of GB 50010-2010 overestimates the bearing capacity of columns with high-strength steel, whereas bearing capacities computed using Codes of ACI 318-14 and CSA A23.3-04 agree well with test results.

scholarly journals Research on Concrete Columns Reinforced with New Developed High-Strength Steel under Eccentric Loading

Materials ◽  
2019 ◽  
Vol 12 (13) ◽  
pp. 2139 ◽  
Author(s):  
Yonghui Hou ◽  
Shuangyin Cao ◽  
Xiangyong Ni ◽  
Yizhu Li
Keyword(s):  
Yield Strength ◽  
Bearing Capacity ◽  
High Strength Steel ◽  
High Strength ◽  
Concrete Columns ◽  
Lower Amount ◽  
Transverse Reinforcement ◽  
Longitudinal Reinforcement ◽  
Small Eccentricity ◽  
Failure Patterns

The use of new developed high-strength steel in concrete members can reduce steel bar congestion and construction costs. This research aims to study the behavior of concrete columns reinforced with new developed high-strength steel under eccentric loading. Ten reinforced concrete columns were fabricated and tested. The test variables were the transverse reinforcement amount and yield strength, eccentricity, and longitudinal reinforcement yield strength. The failure patterns were compression and tensile failure for columns subjected to small eccentricity and large eccentricity, respectively. The same level of post-peak deformability and ductility could only be obtained with a lower amount of transverse reinforcement when high-strength transverse reinforcements were used in columns subjected to small eccentricity. The high-strength longitudinal reinforcement improved the bearing capacity and post-peak deformability of the concrete columns. Furthermore, three different equivalent rectangular stress block (ERSB) parameters for predicting the bearing capacity of columns with high-strength steel are discussed based on test and simulated results. It is concluded that the China Code GB 50010-2010 overestimates the bearing capacity of columns with high-strength steel, whereas the bearing capacities computed using the America Code ACI 318-14 and Canada Code CSA A23.3-04 agree well with the test results.

Sign in / Sign up

Export Citation Format

Share Document