Analysis of Mechanical Behavior of Doubler Plate Reinforced CHS-to-SHS T-joint

Zhishen Yuan; Yangzhi Zhao; Shuchen Gan

doi:10.6919/ICJE.202506_11(6).0019

Authors

Zhishen Yuan
Yangzhi Zhao
Shuchen Gan

DOI:

https://doi.org/10.6919/ICJE.202506_11(6).0019

Keywords:

Doubler Plate Reinforced CHS-to-SHS T-joint; Bearing Capacity; Parametric Analysis; Correction Factor; Formula Fitting.

Abstract

In order to address the issue of localised plastic damage to CHS-to-SHS T-joint, which occurs as a result of the axial pressure exerted by the branch pipe, an improvement in the bearing capacity of thejoint has been achieved through the welding of a cladding plate to the surface of the main pipe. The finite element model of CHS-to-SHS T-joint was verified based on the results of the tests conducted on the joint. The verification was carried out using the joint load-displacement curve, damage mode and bearing capacity. The verified model was reinforced with the cladding plate, and a finite element parameter analysis was conducted to ascertain the strengthening law of the cladding plate on the joint. Subsequently, a design formula for the bearing capacity of CHS-to-SHS T-joint reinforced with the cladding plate was established through linear regression. The analysis results demonstrate that increasing the thickness, width and length of the cladding plate can enhance the compressive load-bearing capacity of the joint. However, it is observed that the greatest improvement in load-bearing capacity is achieved when the thickness of the cladding plate is increased.When the thickness and width of the cladding plate remain unchanged,the reinforcing effect of the cladding plate with a length ratio of the cladding plate to the main pipe of 1.2 is the best.For the reinforced joints with the same cladding plate size,the enhancement ratio of joint will improve more while the width ratio of branch to main tube (β) is smaller.The CHS-to-SHS T- joint,reinforced by the cladding plate,may be over-reinforced because of a small or large branch-to-main pipe width ratio (β) .The results of the formula presented in the paper are in close alignment with the parameter analysis results.

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