Recently, as the number of earthquakes has increased, the building structure standard has been revised in 2016. In order to minimize earthquake damage, steel frame is used as the most economical and efficient lateral resistance system. Also, when the steel braces are subject to Compressive load, which causes unstable behavior of the structure. In order to verify the compressive behavior of the reinforced Braces, structural performance tests were conducted with variables of slenderness ratio and the amount of reinforcement. This study investigates the structural performance of existing double - angle steel braces by reinforcing them with non- welded/assembled light-weight steel frames and proposes a suitable reinforced section.
Building hardware joints are welded in most cases, which have risks of fire and explosion. Besides, the secondary damage of the destruction of the welded parts can be caused by the horizontal displacement of the structure due to earthquake or wind load. This paper compared the horizontal displacement following abilities of welded building hardware and non-welded building hardware. To do this, We conducted actual formation shake table test, and checked on the horizontal displacement following ability of structure by comparing their responses to earthquake load. We made the 2m-high framework to examine the responses of the actually constructed building hardwares, and analyzed the displacement responses of the welded-typed, non-welded-typed, and cruciform bracket building hardwares. We conducted the test by increasing acceleration rate until displacement reached 40mm corresponding to allowable relative story displacement II. The result of the test showed that the building hardware using welding work made cracking and breakage on welded connections of welded building hardware, but non-welded building hardware with no use of welding work and cruciform bracket building hardware make no problem, and that non-welded building hardware is superior to that of the welded building hardware in the horizontal displacement following ability due to earthquake or wind load.
The dissertation is on the measurement of the strain caused by the characteristics and the temperature changes of the TIG welded zone which is used with 3D ESPI system that is functionally modified through the laser ESPI system. Experimental results have derived from the fact that the welded zone has micro crack during the various phased of the process such as rolling, alkali cleaning, air cooling and heat processing due to the repetitious up-and-down of the temperature. Especially, both 60℃ and 90℃ are selected to measure the strain on the welded zone which can be effected by these two temperatures in the manufacturing process. The flat plate differences between ESPI and the strain gage are within 2 %, and they are the exactly same with the results from the temperature changes of 60 ℃ and 90 ℃, and also within 3 % and 4 %. As the tensile load increase, the strain of aluminum material increases linearly. Also the same effect are observed as the temperature goes up with irregular-line type. The comparison of the strain by ESPI and the strain gage in the welded specimen is within the 2.6% when it is under the room temperature and low-load conditions, while it is measured within 3 % under the high load condition.
The non-welded building hardware method can reduce accidents caused by welding, and can be constructed by bolt assembly, which can reduce labor costs and shorten the construction period. The purpose of this study is to evaluate the behavior of joints of non-welded and welded of building hardware frame
If the bracket triangle are commonly used, you may issues such as withdrawal caused by mounting unstable bracket phenomena and bending wire, the eccentricity of the loading plate than steel when you change the angle of the hole during construction will occur. SM brackets adjustment of the angle of 25~40 degrees is possible adjustment of the angle of the ground anchor bracket arched surface, the change in distance between the fixing position of the line and band pieces, due to changes in the installation angle, designers from steel Unlike with the intention, it is possible if the corresponding method can be constructed. Also, For construction of temporary structure used anchor, it will be reinforced with stiffener to prevent excessive deformation of the wale. In general, the welded steel stiffener is used. Construction of welded steel stiffener is costly and time-consuming and cause the problem that wale does not reuse. In order to solve these problems, various kinds of non-weled stiffeners are being developed.
For construction of temporary structure used anchor, it will be reinforced with stiffener to prevent excessive deformation of the wale. In general, the welded steel stiffener is used. Construction of welded steel stiffener is costly and time-consuming and cause the problem that wale does not reuse. In order to solve these problems, various kinds of non-weled stiffeners are being developed. In this paper, non-welded and conventional welded stiffener for maximum strength, fracture pattern and the residual stregth due to cyclic loading is to evaluate.