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The Design of Seismic Moment Connection using Extended End Plate in Smpi Al Azhar Rawamangun
Building
Syafwandi, Ganang Refadana
Faculty of Engineering, Mercu Buana Jakarta University, Indonesia [email protected], [email protected]
Abstract
A steel structure cannot be separated from elements such as beams and columns that must be connected. The connection component can be said to be the weakest part of the steel structure. The failure of steel structures can occur in the connecting components, generally due to inappropriate connection design and mismatch between the analyzed behavior and the actual behavior so that the design and detail of the connection elements is not optimal. One of the connection types that recommended by SNI is the extended end plate type connection, which is the connection made by welding the beam to an end plate and bolting the end plate to a column flange, design guide this connection type refers to SNI 7972: 2013 regulations. In this research the connection design uses 3 types of extended end plate moment connection for special moment frames for seismic applications, namely four-bolt extended unstiffened end plate (4E), four-bolt extended stiffened end plate (4ES), and eight- bolt extended stiffened end plate (8ES). The detailing of the four-bolt extended unstiffened end plate (4E) using the number and diameter of bolts of 8Ø36 and using the end plate thickness of 42 mm, for a four-bolt extended stiffened end plate (4ES) using the number and diameter of bolts 8Ø36 and using the end plate thickness of 34 mm, whereas for the eight-bolt extended stiffened end plate (8ES) using the number and diameter of bolts 16Ø25 and using the end plate thickness of 28 mm. For detailing on the column flange, it is necessary to add stiffener to the three types of connections, as the transfer of load forces on the beam elements to the column elements.
Keywords:
Extended End Plate Connections, Load Forces, Steel Structures, Steel Connections, SMRF
1. Introduction
Steel structure cannot be separated from elements such as beams and columns that must be connected.
The connection component is a major concern in steel structure design, because the connection component is the weakest part of the steel structure (Al- Ma’ruf, 2017). The failure of steel structure can occur in connections or connecting components. This failure is generally caused by inappropriate connection design and a mismatch between the analyzed behavior and the actual behavior, resulting poor design and detailing of the connection elements. Therefore the connection must be designed in such a way as to produce a safe and strong connection against the working load (Adityawarman, Sanim, 2015).
One type of connection in steel structures is the extended end plate moment connection, this connection consists of a plate that is welded to the end part of the beam and then bolted to the column structure. Extended end plate moment connection can be grouped based on the state of the outer of the end plate, namely flush (flat) or extended (expanded). The usage of the end plate connection types according to SNI 7972 : 2013, for connection design in special and intermediate steel moment frames that consider to the seismic factor is recommended using connection type of extended end plates. The behavior of this type of connection can be controlled by a number of different limit states including flexural yielding of the beam section, flexural yielding of the end-plates, yielding of the column panel zone, tension rupture of the end-plate bolts, shear rupture of the end-plate bolts, or rupture of various welded joints. The design criteria provide sufficient strength in the elements of the connections to ensure that the inelastic deformation of the connection is achieved by beam yielding (Nasional, 2015).
In this research, the author will design the connection components in the SMPI Al Azhar Rawamangun building with a structure using the I-Wide Flange profile on the beam, also using King Cross profile on the column. The connection design will use the extended end plate connection type for special moment frames in seismic applications according to Nasional, (2015).
1.1 Objectives
Based on the background that has been described, several main issues to be discussed are as follows:
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moment connections for special moment frames, namely four-bolt extended unstiffened end plate (4E), four-bolt extended stiffened end plate (4ES), and eight-bolt extended stiffened end plate (8ES). In the initial stage, it begins with collecting data consisting of general data from the building to be studied.
1. Building Name : SMPI Al Azhar Rawamangun
2. Location : Jl. Sunan Giri No. 1 Rawamangun, East Jakarta 3. Building Function : School
4. Number of Floors : 5 floors 5. Building Height : 16.8 m
6. KDS : D
7. Structure System : Special Moment Resisting Frame (SMRF) 8. Type of Soil : Moderate
9. Main Structure : I-Wide Flange Beam King Cross and Queen Cross Non-Composite Beam 10. Steel Quality : BJ 37
11. Structure Design : a. Beam Dimension
B 1 Beam (2nd – 5th floors) = IWF 600 x 200 x 11 x 17
B 2 Beam (2nd – 5th floors) = IWF 600 x 200 x 11 x 17
B 3 Beam (2nd – 5th floors) = IWF 500 x 200 x 10 x 16
B 4 Beam (2nd – 5th floors) = IWF 400 x 200 x 8 x 13
B 5 Beam (2nd – 5th floors) = IWF 350 x 175 x 7 x 11
B 6 Beam (Rooftop) = IWF 250 x 125 x 6 x 9
B 7 Beam (Rooftop) = IWF 150 x 100 x 6 x 8
b. Column Dimension
Exterior Column = QC 700 x 300 x 13 x 24
Interior Column = KC 700 x 300 x 13 x 24
After that, a literature study was carried out that related to research, starting from searching for relevant references and the regulations that became references. Furthermore, a preliminary design is carried out.
Continued with loading which includes live load, dead load, wind load and earthquake load. After loading is complete, then input the loading results into modeling and structural analysis of the design using the ETABS v.2013program. (Figure 1).
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Figure 1. Building structure modeling Source: Personal document
Next, determine the maximum load forces that work on the structural elements. After that, control the dimensions of the structural elements that will be used. If the dimensional control process does not meet the requirements, a preliminary redesign is carried out.
After the design of the structure and the dimensions of the structural elements is completed, make detailing for the extended end plate connections on the building beam and column components is in accordance with the special moment resisting frame that refers to Nasional, (2015) (Figure 2), then an output detail drawing of the design structure will be generated for the beam and column detailing using the AUTOCAD 2015 program.
Figure 2. End plate configuration extended:
a) four-bolt extended unstiffened end plate, 4E ; (b) four-bolt extended stiffened end plate, 4ES ; b) extended stiffened end plate, 8ES
Source: SNI 7972: 2013
3. Results and Discussion
In this research, connection design will be carried out using 3 types of extended end plate seismic moment connections for special moment frames, namely four-bolt extended unstiffened end plate (4E), four-bolt extended stiffened end plate (4ES), and eight-bolt extended stiffened end plate (8ES). The three types of connections are designed on the same beam and column profiles, with load of VD = 11363.14 kg and VL = 9911.38 kg which is obtained from the Etabs v.2013 program.
From the design results that refers to the Nasional, (2015) regulation, the capacity and detailing values of the three types of extended end plate connections are as follows:
(a) (b) (c)
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Figure 3. Detailing of four-bolt extended unstiffened end plate, 4E Source: Personal document
Figure 4. Approximate plastic joint in four-bolt extended unstiffened end plate, 4E Source: Personal document
Figure 5. Detailing at the column structure in four-bolt extended unstiffened end plate, 4E Source: Personal document
END PLATE
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Figure 6. Detailing of four-bolt extended stiffened end plate, 4ES Source: Personal document
Figure 7. Approximate plastic joint in four-bolt extended stiffened end plate, 4ES Source: Personal document
Figure 8. Detailing at the column structure in four-bolt extended stiffened end plate, 4ES Source: Personal document
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Figure 9. Detailing of eight-bolt extended stiffened end plate, 8ES
Figure 10. Approximate plastic joint in eight-bolt extended stiffened end plate, 8ES Source: Personal document
Figure 11. Detailing at the column structure in eight-bolt extended stiffened end plate, 8ES Source: Personal document
From the design results, it is known that the usage of the connection type in the extended end plate type connection will affect to the details used, such as the number of bolts used, the diameter of the bolts and the thickness of the end plate used.
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Table 1. Detailing of extended end plate connection
Extended End Plate Connection Type Four-Bolt
Unsiffened (4E)
Four-Bolt Stiffened (4ES)
Eight-Bolt Stiffened (8ES)
Detailing on Beam Structure Number and Diameter of
Bolts Used 8 Ø36 8 Ø36 16 Ø25
Stiffener Plate Thickness - 12 mm 12 mm
Stiffener Plate
Dimensions - 150 x 260 mm 190 x 330 mm
End Plate Thickness 42 mm 34 mm 28 mm
Detailing on Column Structure, Thickness of Stiffener Plates on
Column Flange
35 mm 35 mm m
Source: Personal document
From the design results, the results obtained regarding the load forces that meet with the conditions of the strong column-weak beam according to SNI 7972: 2013.
Table 2. Internal forces at the extended end plate connection Extended End Plate
Connection Type
Shear Rupture Strength At Compression Flange
Moment at The Face of The Column
Status
Ru (Kg) фRn (Kg) Mf (Kgm) Mnp
(Kgm) Four-Bolt Unstiffened
(4E) 45231.46 113595 125457.44 147168.6 OK
Four-Bolt Stiffened
(4ES) 45136.65 113595 124751.9 147168.6 OK
Eight-Bolt Stiffened
(8ES) 45468.23 109563 127210.8 141945 OK
Source: Personal document
4. Conclussion
From the results of the design analysis of the extended end plate seismic moment connection at the SMPI Al Azhar Rawamangun building, the following conclusions can be drawn:
1. The usage of the connection type in the extended end plate connection type will affect the details of the connection such as the number and diameter of the bolts used, the thickness of the stiffener plate, the dimensions of the stiffener plate, the thickness of the end plate and the detailing of the column elements used.
2. Connection design using the largest load forces that available on one floor, and design on beams with I Wide Flange profiles 600 x 200 x 11 x 17 and on column with King Cross profiles 700 x 300 x 13 x 24.
3. The calculation of the connection using 3 types of end plate extended seismic moment connection for the special moment reisisting frame that refers to the SNI 7972: 2013 regulation, namely four-bolt extended unstiffened end plate (4E), four-bolt extended stiffened end plate (4ES), and eight-bolt extended stiffened end plate (8ES).
4. Based on the strength analysis of 3 types of extended end plate seismic moment connections, there are results that meet the requirements, in other words the connection components are able to withstand loads that work well against shear forces, and the combination of normal forces and moments obtained.
5. In the four-bolt extended unstiffened end plate (4E), it is known that the shear rupture strength at compression flange is Ru = 45231.46 kg while the nominal shear rupture strength at compression flange capacity value resulting from the connection is Rn = 113595 kg. Then, the results of the moment at the face of the column is Mf = 125457.44 kgm while the nominal moment capacity value result from the connection is Mnp = 147168.6 kgm. So that four-bolt extended unstiffened end plate (4E), is able to withstand the loads that work.
6. In the four-bolt extended stiffened end plate (4ES), it is known that the shear rupture strength at compression flange is Ru = 45136.65 kg while nominal shear rupture strength at compression flange capacity value resulting from the connection is Rn = 113595 kg. Then, the results of the moment at the face of the column is Mf = 124751.9 kgm while the nominal moment capacity value resulting from the connection is Mnp = 147168.6 kgm. So that the four-bolt extended stiffened end plate (4ES) is able to withstand the loads that work.
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stiffened end plate (4ES) and four-bolt extended unstiffened end plate (4E) connection that is a bolt with a diameter of 25 mm, while others use a bolt with a diameter 36 mm.
10. Another detailing design for the four-bolt extended unstiffened end plate (4E) is to use a 35 mm thick stiffener plate on the column flange as the transfer of load forces on the beam elements to the column elements.
11. Another detailing design for the four-bolt extended stiffened end plate (4ES) is to use a stiffener plate thickness on a beam of 12 mm thick with dimensions of 150 mm x 260 mm. Then on the column flange of the connection using a stiffener plate thickness of 30 mm as the transfer of load forces on the beam elements to the column elements.
12. Another detailing plan for the eight-bolt extended stiffened end plate (8ES) is to use a stiffener plate thickness on a beam of 12 mm thick with dimensions of 190 mm x 330 mm. Then on the column flange of the connection using a stiffener plate thickness of 35 mm as the transfer of load forces on the beam elements to the column elements.
References
Adityawarman, Sanim, S. (2015). Pengaruh Beban Kerja Terhadap Kinerja Karyawan PT. Bank Rakyat Indonesia (persero) Tbk Cabang Krekot. Manajemen Dan Organisasi, VI.
Al- Ma’ruf, A. I. dan F. N. (2017). Pengkajian Sastra Teori dan Aplikasi. CV Djiwa Amarta Press.
Nasional, B. S. (2015). “Spesifikasi Untuk Bangunan Baja Struktural, SNI 1729:2015". Jakarta: Badan Standardisasi Nasional.
Biography
Prof. Dr. Syafwandi, M.Sc. Born in Jakarta on October 13, 1956. He is a lecturer at the Faculty of Civil Engineering, Mercu Buana University. Bachelor’s degree education was obtained from the University of Indonesia in 1984. Master's education was obtained from the Bandung Institute of Technology and University College London in 1988. Doctoral education was obtained from Satyagama University in 2005. He has experience as a Technical Consultant in the Department of Public Works; Underdeveloped Village Department;
Regional Development Planning Agency, and as Director of the Postgraduate Program at the Menara Siswa College of Administrative Sciences.
Ganang Refadana. Born in Jakarta on November 1, 1997. He will receive a Bachelor's degree in Civil Engineering at Mercu Buana University in 2021. He obtained an Associate Engineering degree from the Jakarta State Polytechnic in 2018. He is currently working at PT Shimizu Corporation on the construction of several projects on Java Island.
