EXPERIMENTAL INVESTIGATION OF THE BEHAVIOR OF COLUMN BASE CONNECTIONS WITH CONCENTRICALLY WELDED ANCHOR RODS USING DIGITAL IMAGE CORRELATION METHOD

Base plate connections are one of the most important connections in steel structures. Besides the moment capacity of the connection, the rotational stiffness is an equally critical property that is frequently used in design. Because of the low rotational stiffness of the column base-plate, column ba...

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Main Authors: I. Karami, S.R. Mirghaderi, A.R. Ghiami Azad, M. Ali
Format: Article
Language:fas
Published: Sharif University of Technology 2024-12-01
Series:مهندسی عمران شریف
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Online Access:https://sjce.journals.sharif.edu/article_23502_73f1cead9f4ffae7f1902fed71b0152a.pdf
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author I. Karami
S.R. Mirghaderi
A.R. Ghiami Azad
M. Ali
author_facet I. Karami
S.R. Mirghaderi
A.R. Ghiami Azad
M. Ali
author_sort I. Karami
collection DOAJ
description Base plate connections are one of the most important connections in steel structures. Besides the moment capacity of the connection, the rotational stiffness is an equally critical property that is frequently used in design. Because of the low rotational stiffness of the column base-plate, column base-plate connections do not have enough rigidity to create perfect plastic hinges. Therefore, concentrically-welded anchor rods were used under the column base plate to transfer loads properly. In this paper, four different weld types were used to connect the anchor rods to the bottom of the base plate. In this new connection, the eccentricity between anchor rods and the steel column is removed to improve the strength and stiffness of the base plate connections. The aim of this paper is to design four different weld types according to the specifications of welding standards. Five laboratory samples with different anchor rod strengths were tested to evaluate strength and ductility of each weld type under tensile loading. Anchor rods were the weakest member in transferring tensile load in each sample and expected to fail at the end of the test. Digital Image Correlation (DIC) method was used to provide force-displacement diagram and full field strain information of each laboratory sample. DIC is a non-contact and non-destructive technique in which digital images of the point of interest (POI) of a test specimen are captured continuously using a high-resolution camera all through the test. Fortunately, experimental results were similar to DIC results. Brittle failure was observed in the samples with high strength anchor rods at the softened heat affected zone (HAZ) in the anchor rods. As a result, all the anchor rods in each laboratory sample fractured at a tensile strength higher than yield strength of the anchor rod. Therefore, to prevent the failure of anchor rods in softened HAZ area, it is recommended to design the anchor rods of the column base connections to remain elastic under cyclic loads. It was also concluded that the fillet weld had a better performance in terms of executive and economy compared to the other welds.
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series مهندسی عمران شریف
spelling doaj-art-456c0b151dcb474084d27c5090e243702025-02-02T10:57:49ZfasSharif University of Technologyمهندسی عمران شریف2676-47682676-47762024-12-0140313815210.24200/j30.2024.63404.327123502EXPERIMENTAL INVESTIGATION OF THE BEHAVIOR OF COLUMN BASE CONNECTIONS WITH CONCENTRICALLY WELDED ANCHOR RODS USING DIGITAL IMAGE CORRELATION METHODI. Karami0S.R. Mirghaderi1A.R. Ghiami Azad2M. Ali3M.S., School of Civil Engineering, College of Engineering, University of Tehran, Iran.Professor, School of Civil Engineering, College of Engineering, University of Tehran, Iran.Assistant Professor, School of Civil Engineering, College of Engineering, University of Tehran, Iran.Ph.D., School of Civil Engineering, College of Engineering, University of Tehran, Iran.Base plate connections are one of the most important connections in steel structures. Besides the moment capacity of the connection, the rotational stiffness is an equally critical property that is frequently used in design. Because of the low rotational stiffness of the column base-plate, column base-plate connections do not have enough rigidity to create perfect plastic hinges. Therefore, concentrically-welded anchor rods were used under the column base plate to transfer loads properly. In this paper, four different weld types were used to connect the anchor rods to the bottom of the base plate. In this new connection, the eccentricity between anchor rods and the steel column is removed to improve the strength and stiffness of the base plate connections. The aim of this paper is to design four different weld types according to the specifications of welding standards. Five laboratory samples with different anchor rod strengths were tested to evaluate strength and ductility of each weld type under tensile loading. Anchor rods were the weakest member in transferring tensile load in each sample and expected to fail at the end of the test. Digital Image Correlation (DIC) method was used to provide force-displacement diagram and full field strain information of each laboratory sample. DIC is a non-contact and non-destructive technique in which digital images of the point of interest (POI) of a test specimen are captured continuously using a high-resolution camera all through the test. Fortunately, experimental results were similar to DIC results. Brittle failure was observed in the samples with high strength anchor rods at the softened heat affected zone (HAZ) in the anchor rods. As a result, all the anchor rods in each laboratory sample fractured at a tensile strength higher than yield strength of the anchor rod. Therefore, to prevent the failure of anchor rods in softened HAZ area, it is recommended to design the anchor rods of the column base connections to remain elastic under cyclic loads. It was also concluded that the fillet weld had a better performance in terms of executive and economy compared to the other welds.https://sjce.journals.sharif.edu/article_23502_73f1cead9f4ffae7f1902fed71b0152a.pdfbase plate connectiont-shape connectioncomponent methodgroove weldfillet weldanchor roddic
spellingShingle I. Karami
S.R. Mirghaderi
A.R. Ghiami Azad
M. Ali
EXPERIMENTAL INVESTIGATION OF THE BEHAVIOR OF COLUMN BASE CONNECTIONS WITH CONCENTRICALLY WELDED ANCHOR RODS USING DIGITAL IMAGE CORRELATION METHOD
مهندسی عمران شریف
base plate connection
t-shape connection
component method
groove weld
fillet weld
anchor rod
dic
title EXPERIMENTAL INVESTIGATION OF THE BEHAVIOR OF COLUMN BASE CONNECTIONS WITH CONCENTRICALLY WELDED ANCHOR RODS USING DIGITAL IMAGE CORRELATION METHOD
title_full EXPERIMENTAL INVESTIGATION OF THE BEHAVIOR OF COLUMN BASE CONNECTIONS WITH CONCENTRICALLY WELDED ANCHOR RODS USING DIGITAL IMAGE CORRELATION METHOD
title_fullStr EXPERIMENTAL INVESTIGATION OF THE BEHAVIOR OF COLUMN BASE CONNECTIONS WITH CONCENTRICALLY WELDED ANCHOR RODS USING DIGITAL IMAGE CORRELATION METHOD
title_full_unstemmed EXPERIMENTAL INVESTIGATION OF THE BEHAVIOR OF COLUMN BASE CONNECTIONS WITH CONCENTRICALLY WELDED ANCHOR RODS USING DIGITAL IMAGE CORRELATION METHOD
title_short EXPERIMENTAL INVESTIGATION OF THE BEHAVIOR OF COLUMN BASE CONNECTIONS WITH CONCENTRICALLY WELDED ANCHOR RODS USING DIGITAL IMAGE CORRELATION METHOD
title_sort experimental investigation of the behavior of column base connections with concentrically welded anchor rods using digital image correlation method
topic base plate connection
t-shape connection
component method
groove weld
fillet weld
anchor rod
dic
url https://sjce.journals.sharif.edu/article_23502_73f1cead9f4ffae7f1902fed71b0152a.pdf
work_keys_str_mv AT ikarami experimentalinvestigationofthebehaviorofcolumnbaseconnectionswithconcentricallyweldedanchorrodsusingdigitalimagecorrelationmethod
AT srmirghaderi experimentalinvestigationofthebehaviorofcolumnbaseconnectionswithconcentricallyweldedanchorrodsusingdigitalimagecorrelationmethod
AT arghiamiazad experimentalinvestigationofthebehaviorofcolumnbaseconnectionswithconcentricallyweldedanchorrodsusingdigitalimagecorrelationmethod
AT mali experimentalinvestigationofthebehaviorofcolumnbaseconnectionswithconcentricallyweldedanchorrodsusingdigitalimagecorrelationmethod