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To enhance the seismic performance of traditional eccentrically braced frame structures, this study introduces an innovative mid-splice replaceable link. Compared to conventional welded links, this novel link uses high-strength bolted splices to effectively prevent the premature loss of energy dissipation capacity caused by weld tearing. The replaceable link is available in two variations, distinguished by the types of holes in the web and web splicing plates: standard holes and slotted holes. Cyclic loading tests indicate that the detailed splicing of the replaceable link results in full hysteretic curves and robust energy dissipation capacities. Additionally, this design minimizes deformation of the end plates, allowing for easy disassembly. The high-strength bolts in the web and web splicing plates dissipate energy through slipping, which is the primary mechanism in slotted hole specimens and differs from conventional link methods. Using low-yield-point steel (LYP160), the replaceable link achieves a plastic rotation range from 0.19 to 0.21 rad, which significantly surpasses the 0.08 rad required by AISC 341–16, indicating superior plastic deformation capacity. Furthermore, the overstrength factor of the replaceable link ranges from 3.33 to 5.22, showcasing excellent overstrength performance. • Cyclic response and failure mode of mid-splice replaceable link constructed of LYP160 is verified by cyclic loading tests. • The link exhibits stable and complete hysteresis loop, excellent plastic rotation and ductility. • High overstrength of mid-splice replaceable link, indicated reliable seismic performance and energy dissipation capability • Using unique hole types in the web and splicing plate, energy dissipation by high-strength bolt slippage is viable mechanism [ABSTRACT FROM AUTHOR]

The study introduces an innovative design for enhancing the energy-dissipating capacity and replaceability of eccentrically braced steel frames using a two-segment replaceable shear link. This design features a 10 mm gap in the mid-length, providing an installation tolerance for easy disassembly. The two segments are connected through channel splicing plates and side plates, emphasizing concentrated plastic deformation in the energy-dissipating region. Fully bolted connections involve non-energy-dissipating components, allowing efficient elastic design and focused plastic behavior. To evaluate seismic performance, two types of replaceable links were designed for cyclic loading tests: one with standard holes and the other with slotted holes in the side plate and channel splicing plate. Test results highlight localized plastic deformation in the energy-dissipating region, with failures such as broken welds, severe flange buckling, and web plate tearing. Stable hysteresis curves exhibit good ductility, energy dissipation, and plastic deformation. The ultimate plastic angle exceeds 0.13 rad, surpassing the AISC 341–16 limit of 0.08 rad. Ductility coefficients range from 6.10 to 7.99, and overstrength coefficients range from 1.82 to 2.09, exceeding the AISC 341–16 limit of 1.5. Furthermore, a two-stage design method for bolted connections, accounting for bolt slip, is proposed. This method enhances the overall understanding and utilization of these innovative replaceable shear links, providing a comprehensive solution for improving the seismic performance of eccentrically braced steel frames. • The seismic performance of two-segment replaceable link with channel splicing plate is evaluated by cycle loading test. • The hysteresis curves of the replaceable link are full and the specimens have a strong plastic deformation capacity. • The experimental study showed that the overstrength coefficient (Ω) for the replaceable link ranged from 1.82 to 2.09. • The bolts slip in the channel splicing plate dissipate more energy due to the slotted hole. [ABSTRACT FROM AUTHOR]

Traditional I-beam sections connected with end plates face challenges related to end bolts and excessive residual deformation. In response to these challenges, this study introduces an innovative concept: two-segment replaceable links with separated splicing plates. Two variations of replaceable links have been designed - one with separated splicing plates featuring standard bolt holes, and another with short slotted bolt holes. Cyclic loading tests has been conducted to study their seismic performance. The test results reveal that the failure modes of the links include flange buckling and tearing at the welds connecting the flange and end plate. The hysteresis curves of the specimens are complete and stable. The average overstrength coefficient of the links is 1.75, meeting the specified limit requirement for an overstrength coefficient greater than 1.5 for the link. The ultimate plastic rotation reaches up to 0.19 rad. Notably, specimens with short slotted bolt holes exhibit a relatively significant energy dissipation ratio due to bolts slip during test and they demonstrate optimal replaceability in terms of minimized replacement time and residual shear rotation. Furthermore, the two-stage design method for high-strength bolts in splicing plate is proposed considering bolts slip. • To evaluate the seismic performance of the two-segment replaceable link with separated splicing plates. • The hysteresis curves of the replaceable link are full and the specimens have a strong plastic deformation capacity. • The experimental study showed that the overstrength coefficient (Ω) for the replaceable link ranged from 1.52 to 2.00. • The bolts slip in the splicing plate dissipate more energy due to the long circle holes. [ABSTRACT FROM AUTHOR]

This paper presents an innovative design for replaceable shear links, incorporating a variable cross-section that emphasizes concentrated plastic deformation in the energy-dissipating region. The design employs fully bolted connections involving non-energy-dissipating components, enabling both efficient elastic design and focused plastic behavior. To evaluate the seismic performance of this variable cross-section replaceable link, three section configurations were developed for cyclic loading tests: a low-yield-point (LYP160) specimen with an unchanged energy-dissipating region, a Q235 steel specimen with circular holes in the energy-dissipating region, and a Q235 steel specimen with elongated holes in the same region. Experimental results emphasize that plastic deformation is primarily localized in the energy-dissipating region, with failures characterized by buckling and tearing around the region's holes. Notably, the low-yield-point specimen exhibits an overstrength coefficient of up to 3.65, displaying a complete hysteresis curve, exceptional energy dissipation capacity, and a plastic rotation of 0.18 rad. Conversely, the elongated-hole specimen demonstrates notable overstrength exceeding 1.70, but its energy dissipation is compromised due to the weakened section. In contrast, specimens with circular holes exhibit an initial elastic stiffness similar to low-yield-point steel specimens, outperforming elongated-hole specimens by around 84% in stiffness. Additionally, a two-stage design method for bolted connections, accounting for bolt slip, is proposed. This approach enhances the overall understanding and utilization of these innovative replaceable shear links. • To evaluate the seismic performance of the variable cross-section replaceable link by cyclic loading test. • The hysteresis curves of the replaceable link is full and the specimen has a strong plastic deformation capacity. • The overstrength coefficient (Ω) for the variable cross-section replaceable link ranged from 1.70 to 3.65 • Plastic deformation primarily occurs within the energy-dissipating region in variable cross-section link • The two-stage design method for bolts connection considering bolts slip is proposed. [ABSTRACT FROM AUTHOR]

This paper proposes a prefabricated beam–column joint with L-shaped stiffeners based on the traditional semi-rigid joint and end-plate connection. The joint is suitable for multi-story prefabricated steel frames and a fully bolted assembly construction. To study the seismic performance and failure modes of the joints, cyclic loading test were conducted on three full-scale specimens of prefabricated beam–column joints with L-shaped stiffeners. Furthermore, the rotation stiffness and bearing mechanism of the joint were obtained by an improved component method proposed in this paper. The results of the tests indicated that the failure modes of the joints were buckling and tearing of the flange and web of the beams. Additionally, the load-carrying capacity as well as ductility and energy dissipation capacities of the joints under cyclic loading can be improved by increasing the length and thickness of the L-shaped stiffeners. The rotation stiffness of the joint satisfies the Eurocode 3 moment–rotation model requirements and is suitable to improving the seismic performance analyses of prefabricated steel structures. • The mechanical properties of prefabricated beam–column joints with L-shaped stiffeners were investigated in this paper. • The Moment–rotation curves of joints were established, and the specimen has a strong plastic deformation capacity. • The bearing mechanism is calculated, and the theoretical values agree well with the test values. • The rotation stiffness of joint is established by component method and the initial stiffness is divided into four parts. [ABSTRACT FROM AUTHOR]

Assembled steel structure is widely used as in green building structure with life cycle significance. As the key link in steel structure design, the beam-column joint design has been studied. This paper proposes a new assembled beam-column joint with cantilever beam splicing, four specimens with full sizes were designed. The influence of beam cantilever splicing, the stiffener, and joint direction on seismic performance of the joints were discussed by cyclic loading tests and numerical simulations. Then the sensitivity of key parameters is carried out. The results indicate that the joint with double stiffener in the cantilever beam splicing did not significantly improve the seismic performance of the specimen compared to using a single stiffener; and the initial stiffness was not significantly affected when increasing the length of the L-shaped member. In addition, the stiffness, bearing capacity, and the ductility and bearing capacity of the specimen with weak connection were lower 28.3% and 11.8%, respectively, compared with the joints with strong connection. Parameter analysis showed that increasing the length and thickness of the L-shaped member can effectively improve the seismic performance of the joint, However, the thickness of cantilever beam splices had a small impact on mechanical property. Changing the number of bolts on the flanges of beam had a greater effect on the bearing capacity of the joint. Substituting the initial stiffness of the joint into the EC3 moment-rotation model, the results show that the calculated results are in good agreement with the simulation results and the experimental results. • The seismic performance of a newassembled beam–column joint with cantilever segment is studied by experiment and FEM. • The hysteresis curves are full and plastic deformation is isolated in the beam ends out of the L-shaped members. • The use of a double stiffener in the joint did not significantly improve the seismic performance of the specimen. • The limb thickness and the length of L-shaped member had a significant influence on the load-bearing capacity of the joint. • The min number of bolts in the length of L-shaped member should be 6 to ensure the mechanical properties of joints. [ABSTRACT FROM AUTHOR]

This paper presented the seismic performance of self-centering energy-dissipating link beams that rotate around the vertex. The effects of the connection types of NiTi shape memory alloy (SMA) bar and the material of energy-dissipating steel angle on the self-centering performance, energy-dissipation capacity, bearing capacity, ductility, rotation mode, and strain distribution of link beams were explored through tests. It was verified through theoretical calculation and finite element analysis method, and the specimens were improved in design. The results show that the self-centering link beams have typical flag-shaped hysteretic curves and have excellent self-resetting performances and energy dissipation capabilities. Plastic deformations were concentrated on the steel angles. LY160 steel angle can enable the link beam to obtain better self-centering performance, while the Q235 steel angle can improve the energy dissipation capacity. The full-length SMA bars link beam has better self-centering performance and energy dissipation capacity than the partition SMA bars link beam. The theoretical calculation and finite element analysis results are consistent with the testing results. The self-centering performances of the improved design specimens were improved, but the energy consumption capacities were slightly reduced. The steel angles of the self-centering link beam after an earthquake are easy to replace and can quickly restore the structural function, which effectively solves the post-earthquake large residual deformation and difficulty of repair of traditional link beam. • The self-centering link presented, which solve the large residual deformation and difficult repair of traditional link after earthquakes. • A quasi-static test was conducted, finite element and theoretical calculations verified the test results, an improved design was proposed. • The self-centering performance, energy-dissipation capacity, bearing capacity, ductility, rotation mode, and strain distribution were analyzed. • The connection types of SMA bars and steel angles suitable for self-centering link beams were derived. [ABSTRACT FROM AUTHOR]

Plate-reinforced composite (PRC) coupling beams are manufactured by embedding a vertical steel plate into conventionally reinforced concrete coupling beams to enhance their strength and ductility. This study presents a series of quasi-static tests conducted to examine the seismic behavior of PRC coupling beams and provide a scientific basis for the analysis of the shear bearing capacity of PRC coupling beams. The experimental results of seven PRC coupling beam specimens with low span-to-depth ratio tested under reversed cyclic loading are discussed. Particle image velocimetry technology is used to accurately measure the deformation performance of PRC coupling beams. The influence of span-to-depth ratio, sectional steel plate ratio, and the slab on the seismic behaviors of specimens were investigated. The experimental results indicate that, compared with PRC coupling beams without slab, PRC coupling beams with slab can increase horizontal cracking displacement and significantly improve the shear capacity and energy dissipation capacity of PRC coupling beams without slab. Embedded steel plates can improve the limited values of the shear compression ratio of coupling beams. Nonlinear finite element analysis was also carried out to model the PRC coupling beams. The numerical results indicate that the tension-softening property of concrete was more accurately simulated by the stress-crack width relationship of concrete. The internal force distribution of concrete stress, steel plate shear force, bending moment, and axial force of PRC coupling beams with low span-to-depth ratios were further analyzed. This study will benefit engineers designing PRC coupling beams. • The limited values of the shear compression ratio of coupling beams were significantly improved. • Particle image velocimetry technology is used to accurately measure the deformation performance of PRC coupling beams. • The PRC coupling beam with slab has a greater energy dissipation capacity. • The steel plate along the beam span was under tension, and the distribution of the tension is in M-mode. [ABSTRACT FROM AUTHOR]

The suitability of external integrated lightweight thermal insulation decorative wall panels as a fully bolted prefabricated steel frame enclosure system was studied. The test on the fully bolted prefabricated steel frame with the external integrated lightweight thermal insulation decorative wall panels was completed under quasi-static cyclic loading, and the impact of the beam-column joint types were investigated. The failure mode, lateral stiffness, bearing capacity, energy dissipation capacity, ductility, and strain distribution were analyzed, and the internal forces of the steel frame were calculated. Experimental results show that the external integrated wall has minimal effect on the stiffness and bearing capacity of the fully bolted prefabricated steel frame. Furthermore, the L-shaped angle joints can increase the bearing capacity, energy dissipation capacity, and lateral stiffness evidently and move the joint plastic hinge outwards. The differences between the experimental bearing capacity and the theoretical value of the steel frame were minimal. Significant buckling deformation was observed at the beam-end, and progressive full-field strain at the plastic hinge were distributed in a band shape. The corresponding improved design was proposed. In addition, the failure mode and hysteretic behavior of the structures were studied by finite element analysis, and the influence of the main parameters, such as the number of horizontal and vertical plate bolts, the types of L-shaped angle stiffeners, and the height-span ratio and axial compression ratio of steel frame were discussed. The finite element analysis results were consistent with those of the test. It provided theoretical evidence for the design and application of fully bolted prefabricated steel frame with external integrated lightweight wall panels. • A low-cyclic loading tests of fully bolted prefabricated steel frame with external integrated lightweight wall panels. • The influence of the beam-column joints types on the fully bolted prefabricated steel frame with external integrated lightweight wall panels was studied. • The failure modes, bearing capacity, hysteretic behavior, lateral stiffness, ductility, energy dissipation capacity and strain distribution were analyzed. • The L-shaped angles joints can remarkably increase the structural capacity, stiffness and energy dissipation capacity, it moved the plastic hinge outwards of joints. • The parameter analysis is carried out for fully bolted prefabricated steel frame by finite element analysis. [ABSTRACT FROM AUTHOR]

A shaking table test was carried out on 1:2 scale three-storey K-shaped eccentrically braced frames with high-strength steel (K-HSS-EBFs). The acceleration, displacement, and strain responses of the specimen under different peak acceleration ground motions were measured and analyzed. The natural frequency, acceleration amplification factor, storey drift, and distribution of horizontal seismic actions for the model structure were investigated. Finite element models were established for elastoplastic time history analysis on the model structure. Finite element analysis showed that the links were the weakest part of the structure, especially the webs of the links and welds near the connections between the links and frame beams. The results showed that K-HSS-EBFs may absorb excessive seismic energy, enter the elastoplastic state, and even fail under strong earthquakes owing to shear deformation of the links during vibration. The PBPD method is found to be suitable for use in the design of K-HSS-EBFs. In addition, the K-HSS-EBFs can fulfill the seismic requirements under limiting state. These findings will be helpful for the future design of K-HSS-EBFs. [ABSTRACT FROM AUTHOR]