A Study on the Buckling and Postbuckling Control of Composite Beams with Embedded NiTi Actuators

Choi, Sup; Lee, Jung Ju; Seo, Dae‐Cheol

doi:10.1106/h30n-6tmj-71e7-95k2

Cited by 11 publications

(4 citation statements)

References 14 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…These applications were mainly based on the two properties of SMA: one is the shape change with temperature, where SMA fibers are pre-strained during the curing process and prevented from a transformation to austenite, if the temperature rises during the operational cycle, the fibers transform into austenite and tend to contract, and the recovery tensile stresses develop due to the constraint of the matrix; the other is the mechanical characters variation, where unstrained SMA fibers are embedded within the composite, increase or decrease of the temperature alters the elastic modulus or the damping property of SMA, consequently changing the property of the composite. Owing to these properties, SMA is usually used to generate bending (Chaudhry and Rogers, 1991;Lagoudas and Tadjbakhsh, 1992), control bucking and postbucking (Baz and Tampa, 1989;Choi et al, 1999Choi et al, , 2000, induce or depress vibration (Anders et al, 1990;Baz et al, 1990Baz et al, , 1995Lau et al, 2002), and isolate seism (Graesser and Cozzarelli, 1991). Jonnalagadda et al (1997) investigated the interaction between SMA wires and a host polymer matrix by correlating local displacements and stress fields induced by the embedded wires with SMA-polymer adhesion.…”

Section: Sma Smart Structurementioning

confidence: 99%

Behavior of Smart Concrete Beams with Embedded Shape Memory Alloy Bundles

Zhang³

2007

Journal of Intelligent Material Systems and Structures

View full text Add to dashboard Cite

The behavior of smart concrete beams with embedded shape memory alloy (SMA) bundles is investigated in this study. Two beams measuring 1996 × 99 × 85 cm3, which will be integrated into a smart bridge in a freeway, are manufactured and examined. Each beam contains six trusses of SMA bundles used as actuators to achieve recovery force. The SMA bundles are connected with pre-stressing steel strands and separated from the concrete matrix, so that temperature interaction between SMA bundles and the matrix can be reduced to as low as possible. Some temperature sensors, reinforcement meters, and displacement sensors are used to monitor the active control effect of SMA bundles, all the data are acquired through a 16-channel dynamic data-acquisition system, and each beam is examined several times with different activating current intensity. Experimental results indicate that the recovery force induced by SMA bundles is significant and controllable, the deflection generated by the SMA bundles at the middle span of the beam is about 0.44 mm, and the capability of resisting overload of each beam is about 2.98 kN (average). A relationship between SMA temperature and activating/inactivating time is also formulated. The conclusion is that SMA can be used in civil engineering structures either from a technological or economic aspect.

show abstract

Section: Sma Smart Structurementioning

confidence: 99%

Behavior of Smart Concrete Beams with Embedded Shape Memory Alloy Bundles

Zhang³

2007

Journal of Intelligent Material Systems and Structures

View full text Add to dashboard Cite

show abstract

“…Let ε and k denote the strain and change of curvature-twist vectors, respectively, and let u designate the displacement vector; then the linear kinematic relation can be expressed as (3) and (4) where s represents the length coordinate along the rod; and t is the unit tangent vector.…”

Section: (2) Kinematic Relationsmentioning

confidence: 99%

“…Optical fibers have been used to detect the buckling event in cylindrical shells [2]. Experimental investigation has been carried out on the buckling control of composite beams with embedded Shape Memory Alloys (SMA) [3,4]. This work aims at a theoretical treatment of the stability control of axially compressed elastic rods with the help of metallic or polymeric SMMS.…”

Section: Introductionmentioning

confidence: 99%

Stability Control of Active Compressed Rods with Shape Memory Polymers

Farshad

2001

Journal of Thermoplastic Composite Materials

View full text Add to dashboard Cite

In structural systems, applied compressive force fields cause second-order effects that may not only influence the buckling behavior, but also enhance the internal stress and the deformation field in the structure. Specifically, slender and thin-walled structural elements subjected to compressive force fields may experience buckling instability, which may affect their service life. In the case of imperfection-sensitive systems, loading and geometric imperfections may drastically affect the buckling response and reduce the buckling resistance. This behavior may be positively influenced by a structural adaptation to bending effects. In this connection, an attempt is made to use the potentials of the adaptive systems to influence the second-order as well as the buckling response of the slender compression elements by means of the actuator components. To this end, the stability control problem of adaptive slender rods with embedded Shape Memory Polymer (SMP) actuators is theoretically treated. The main goal of this investigation was to explore the possibility of minimizing the end deflection of a cantilever rod under eccentrically applied force via actuation of an SMP fiber. First, the stability theory of spatial rods is outlined, and the non-linear governing equations of straight rods are derived. The specific case treated is the problem of a cantilever rod with a single eccentric SMP fiber under eccentrically applied end compressive force. Numerical calculations were carried out with the help of the Runge-Kutta method. It is shown that the response of the rod can be effectively controlled by the appropriate action of the SMP actuator. Specifically, the goal of minimizing the end deflection of the eccentrically loaded cantilever rod through the action of the SMP actuator is achieved. In carrying out the computations, the second-order effects arising from the action of SMP fiber as well as the axial force were taken into consideration. Moreover, the follower action of the SMP force was considered.

show abstract

“…This shows that there is a hope to solve one of the unresolved problems in wind turbine blades that is deformation of the plate. Choi etal [9] solved how buckling control reached the post buckling of the beam with the reactive moment. The study is performed experimentally on a laminated composite beam with SMA embedded eccentrically.…”

Section: Introductionmentioning

confidence: 99%

Transformation of Conventional Mechanical Elements to Smart by Adding Sensors and Actuators to Composite Materials

Alhasan

2023

SVU-International Journal of Engineering Sciences and Applicati

View full text Add to dashboard Cite

Adding sensors and actuators to machine elements will make them more active and useful. The idea is elaborated by combination adding these elements to machine elements manufactured of composite materials as well. With this, the properties of composites are supported by the traits of sensing, monitoring as well as actuating. In this study the evidences supporting this idea was presented and generalized to include all machine elements in order to be smart. For more confidence a mathematical model of the most popular engineering elements namely beam is implemented without implanted wires compared with a second one that implanted with two rows of SMA wires, Nitinol. The two models are solved and analyzed with the finite element method; Ansys package software. The results, deflections, stresses, showed how the beam isn't degraded when implanted with wires and still retains its strength. The advantages of this idea are focused mainly on the quality enhancement as well as pre warning failure.

show abstract

A Study on the Buckling and Postbuckling Control of Composite Beams with Embedded NiTi Actuators

Cited by 11 publications

References 14 publications

Behavior of Smart Concrete Beams with Embedded Shape Memory Alloy Bundles

Behavior of Smart Concrete Beams with Embedded Shape Memory Alloy Bundles

Stability Control of Active Compressed Rods with Shape Memory Polymers

Transformation of Conventional Mechanical Elements to Smart by Adding Sensors and Actuators to Composite Materials

Contact Info

Product

Resources

About