Limit state behavior and response sensitivity analysis of endplate steel connections with shape memory alloy bolts

2020 ◽  
Vol 31 (18) ◽  
pp. 2071-2087
Author(s):  
Majid Mohammadi Nia ◽  
Saber Moradi
Keyword(s):  
Shape Memory Alloy ◽  
Shape Memory ◽  
Numerical Study ◽  
Slenderness Ratio ◽  
Limit State ◽  
Local Buckling ◽  
Limit States ◽  
Response Sensitivity ◽  
Cyclic Response ◽  
Steel Connections

Shape memory alloys have been used in developing self-centering steel moment connections. This article presents a numerical study aiming at evaluating the cyclic response sensitivity and limit states of extended endplate steel connections with shape memory alloy bolts. Three-dimensional finite element models are developed and validated against a recent experimental study. Using a statistical design-of-experiment method, the effects of 21 design factors and their interactions on the cyclic response of shape memory alloy connections are assessed. The sensitivity of six response parameters is studied. In addition, four limit states for shape memory alloy connections are discussed, including beam local buckling, bolt excessive axial strain, endplate yielding, and column flange yielding. Results show that endplate thickness, shape memory alloy bolt diameter, beam web slenderness ratio, and shape memory alloy maximum transformation strain are the most influential factors. Furthermore, endplate yielding is found to be the governing limit state in almost 80% of the analyzed connections, whereas shape memory alloy bolt excessive strain and column flange yielding are observed in less than 20% and 5% of the connections, respectively. Beam local buckling is not governing in the analyzed shape memory alloy connections designed as per the AISC 358-16 and AISC 341-16 seismic design requirements for extended endplate connections and highly ductile members.

Numerical Study of the Column Reinforced with Shape Memory Alloy

2021 ◽  
pp. 1061-1071
Author(s):  
Gisha George ◽  
K. R. Bindhu ◽  
Anagha Krishnan Nambissan
Keyword(s):  
Shape Memory Alloy ◽  
Shape Memory ◽  
Numerical Study

Thermal Buckling of Laminated Composite Beams with Embedded Shape Memory Alloy Actuators

2000 ◽  
Vol 34 (18) ◽  
pp. 1529-1547 ◽  
Author(s):  
Sup Choi ◽  
Jung Ju Lee ◽  
Dong Chun Lee
Keyword(s):  
Shape Memory Alloy ◽  
Shape Memory ◽  
Composite Beam ◽  
Shape Recovery ◽  
Slenderness Ratio ◽  
Laminated Composite ◽  
Thermal Buckling ◽  
Lateral Deflection ◽  
Temperature Load ◽  
Laminated Composite Beams

In this paper, the thermal buckling and postbuckling behaviours of a composite beam with embedded shape memory alloy (SMA) wires are investigated experimentally and analytically. For the purpose of enhancing the critical buckling temperature and reduction of the lateral deflection on thermal buckling and postbuckling, the characteristics of thermal buckling are investigated through the use of the shape recovery force. The results of thermal buckling tests using uniformly heated and clamped composite beam specimens with embedded SMA wire actuators are discussed. The temperature-load-deflection behaviour records present quantitatively how the shape recovery force affects the thermal buckling behaviour. For this experiment, we considered the initial geometric imperfections, the slenderness ratio of the beam and the embedding position of the SMA wire actuators. The experimental results show that the shape recovery force reduces the thermal expansion of the composite laminated beam. This results in an increase of the critical buckling temperature and a reduction of the lateral deflection of the beams.

Experimental Study on a Beam-to-Column Connection Using Shape Memory Alloy

2011 ◽  
Vol 374-377 ◽  
pp. 2176-2179 ◽  
Author(s):  
Hong Wei Ma ◽  
Michael C. H Yam
Keyword(s):  
Shape Memory ◽  
Local Buckling ◽  
Hysteresis Loops ◽  
Seismic Behaviour ◽  
Static Tests ◽  
High Deformation ◽  
Steel Connections ◽  
End Plate ◽  
Extended End Plate ◽  
Plate Connections

For ductile beam-to-column connectiosn in steel frame, beam local buckling is difficult and very costly to repair in any post-disaster reconstruction. Shape memory alloys (SMAs) in their austenite states have the ability to recover their original shape after experiencing large deformations. Steel connections retrofitted using SMAs can be endowed with intelligent characteristics. This paper investigates extended end-plate connections using long shank SMA bolts. The SMA connection is designed using a new methodology of avoiding beam local buckling and adopting the strong end-plate. The connection deformations are supposed to concentrate on the SMA bolts. In order to study the seismic behaviour of the connections, quasi-static tests were conducted on both the SMA connection specimens. The test results indicate that the connection can show high deformation capacity with the maximum interstory drift angles beyond 0.02 rad. However, the beam was remained elastic during test and the deformations of the SMA connection were recoverable upon unloading. The load-drift hysteresis loops are flag-shaped for the SMA connection. This indicates that the connection has moderate energy dissipating capacity.

Actuation of a carbon/epoxy beam using shape memory alloy wires

2018 ◽  
Vol 30 (2) ◽  
pp. 186-197 ◽  
Author(s):  
Reza Damansabz ◽  
Fathollah Taheri-Behrooz
Keyword(s):  
Phase Transformation ◽  
Shape Memory Alloy ◽  
Shape Memory ◽  
Shape Memory Effect ◽  
Memory Effect ◽  
Hybrid Composite ◽  
Epoxy Composite ◽  
Numerical Study ◽  
Cohesive Zone Modeling ◽  
Host Structure

Shape memory effect of NiTi wires is utilized to design various smart composite structures. In these systems, smart wires can induce strains in the host structure by their inherent shape memory effect and phase transformation at elevated temperatures. This article presents an experimental and numerical study on the actuation capability of shape memory alloy wires embedded in the carbon/epoxy composite. In the experimental part, hybrid shape memory alloy/carbon/epoxy composite specimens are fabricated and examined to measure induced strains in the host structure by the phase transformation of the shape memory alloy wires. Hybrid composite specimens were clamped at one end, and the shape memory alloy wires were activated using electrical resistive heating. Numerical simulations were carried out using ABAQUS software to simulate the actual thermomechanical behavior of the hybrid composite specimens. A three-dimensional finite element model based on cohesive zone modeling is used to predict interfacial debonding in hybrid composite plates. The results of the parametric study suggest that by increasing Young’s modulus of the host composites, the amount of the induced strain decreases rapidly. However, for Young’s moduli more than 20 GPa, the induced strain will stay almost constant. Moreover, it was confirmed that increasing the shape memory alloy pre-strain without controlling the actuation temperature may result in the reduction of induced strain in the host composites.

Effects of Changing Double Angles Configuration Used as Braces in Seismic Resisting Systems

2018 ◽  
Vol 763 ◽  
pp. 279-286
Author(s):  
Carlos Bermudez ◽  
Oscar Gutierrez
Keyword(s):  
Compressive Strength ◽  
Slenderness Ratio ◽  
Limit State ◽  
Experimental Results ◽  
Limit States ◽  
Torsional Buckling ◽  
Critical Limit ◽  
Flexural Buckling ◽  
Flexural Torsional Buckling ◽  
Buckling Length

Seismic resisting systems consisting of double angles are used in many parts of the world. Generally, these double angles are arranged in the shape of a T, with a very small distance between them. However, sometimes these angles are distanced and faced in order to improve their mechanical characteristics about the axis of symmetry. In the past, their design was made in the same way as the double angles arranged in a T shape, that is, considering the limit states of flexural buckling and buckling by flexural-torsional, but ignoring the properties of the connectors and their effect on the modified slenderness ratio, as well as the fact that in this case the warping constant is not negligible. These parameters are taken into account in this research in order to study the effects of increasing the distance between the connectors and their possible use as braces in seismic resisting systems. The theoretical results were compared with the experimental results of fifty-seven specimens tested in the laboratory of structures of the Universidad Nacional de Colombia – Sede Manizales. The models were classified according to the main angles, the connectors, the total lengths, and the width of separation. All of them were subjected to axial compressive stress, with free rotation at both ends. Three identical specimens of each model were constructed. The flexural buckling length about x-axis was limited to two meters in all specimens tested whereas the flexural bucking length about y-axis and flexural-torsional buckling length were not limited, i.e. these lengths are equivalent to the total length of each specimen tested. This in order that the critical limit state was to be the flexural-torsional buckling as a function of the torsional buckling term in Z, except in the models of class 2 in which this induced condition was not reached. This was proposed to better evaluate the torsional buckling term in Z. The experimental results show that the nominal compressive strength for the flexural-torsional buckling limit state, when it is governed by torsion, is undervalued. A new methodology is proposed for the calculation of the nominal compressive strength for the flexural-torsional buckling limit state, when it is governed by torsion.

FEA of a Laminate Internal Buckle Arrestor for Deep Water Pipe-in-Pipe Flowlines

2009 ◽  
Author(s):  
Haoyu Wang ◽  
Jason Sun ◽  
Paul Jukes
Keyword(s):  
Deep Water ◽  
Mechanical Design ◽  
Limit State ◽  
Local Buckling ◽  
Design Parameters ◽  
Limit States ◽  
Element Analysis ◽  
Operational Lifetime ◽  
Buckle Propagation ◽  
Buckle Arrestors

Development of deepwater oil reservoirs has been undertaken in the Gulf of Mexico (GoM) where flowlines are installed in water depths in the vicinity of 2,740m (9,000ft). Preventing the propagation of local collapse/buckle failures is one of the key engineering design limit states that is defined in the industry codes to ensure the pipeline integrity. Deep-water buckle propagation is almost unavoidable as the wall thickness selection cannot be directly driven by the buckle propagation limit state. Field data indicates that once a buckle happens, the flowline could collapse for many kilometers instantly. Buckle propagation could cause substantial economic impact if left uncontrolled. For Pipe-in-Pipe (PIP) flowline, due to lack of pressure differential, the jacket pipe is a fragile component in terms of buckle propagation. It is crucial to prevent any possible local buckling during the flowline installation and during the entire operational lifetime. One way to stop buckle propagation is to utilize buckle arrestors of various types. Successfully designed buckle arrestors can contain such disasters to a limited pipeline section. Internal buckle arrestors are a relatively new solution for PIP systems being investigated by the industry. As it is installed in the annulus of PIP, it becomes a preferred choice since it fits all types of installation methods. The objective of this paper is to present the design and finite element analysis (FEA) of a laminate type internal buckle arrestor, and to investigate the effectiveness of this innovative buckle arrestor design for deepwater flowline. Sensitivities of key design parameters are explored with the purpose of guiding detailed mechanical design.

scholarly journals Numerical Study of RC Beams Strengthened with Fe-Based Shape Memory Alloy Strips Using the NSM Method

2021 ◽  
Vol 11 (15) ◽  
pp. 6809
Author(s):  
Yeong-Mo Yeon ◽  
Ki-Nam Hong ◽  
Sugyu Lee ◽  
Sang-Won Ji
Keyword(s):  
Shape Memory Alloy ◽  
Shape Memory ◽  
Control Method ◽  
Numerical Study ◽  
Fe Analysis ◽  
Flexural Behavior ◽  
Fe Model ◽  
Rc Beams ◽  
Near Surface ◽  
Fiber Element

This paper presents a finite element (FE) analysis for predicting the flexural behavior of reinforced concrete (RC) beams strengthened with Fe-based shape memory alloy (Fe-SMA) strips using a near surface mounted (NSM) method. Experimental results reported in the literature were used to verify the proposed FE model. FE analyses were conducted using OpenSees, a general-purpose structural FE analysis program. The RC beam specimens were modeled using a nonlinear beam-column element and a fiber element. The Concrete 02 model, Steel 01 model, and Pinching 04 model were applied to the concrete, steel reinforcement, and Fe-SMA strip in the fiber element, respectively, and the FE analysis was carried out in a displacement control method based on the Newton-Raphson method. The FE model of this study accurately predicted the initial crack load, yield load, and ultimate load. From parametric analyses, it was concluded that an increase in the compressive strength of the concrete increases the ductility of the specimen, and an increase in the level of recovery stress on the Fe-SMA strip increases the initial stiffness of the specimen.

Sign in / Sign up

Export Citation Format

Share Document