Bond strength in wood filled rectangular hollow steel tubes Bharatesh Adappa Danawade a,⇑ , Ravindra Rachappa Malagi a,b a Department of Mechanical Engineering, Gharda Institute of Technology, Lavel University of Mumbai, 415708, India b Department of Product Development and Manufacturing, Visvesvaraya Technological University, Belagavi 590 014, India article info Article history: Received 7 January 2020 Accepted 13 February 2020 Available online 21 March 2020 Keywords: Bond strength Mechanical bond Adhesive bond Interference fit Confinement Pull out tests abstract The objective of this paper is to present experimental work on bond strength of mechanical and adhesive bonded teakwood filled rectangular sectioned hollow steel tubes. Bond between the wood and steel tube interface is due to interference fit between wood and steel tube, confinement of teakwood due to steel tube and friction between teakwood and steel tube. To enhance the bond strength multipurpose epoxy adhesive for structural application was used. Pull out tests were carried out on universal testing machine to study the bond behaviour. Load Vs slip curves were drawn for both mechanical and adhesive bonded wood filled steel tubes. Use of adhesive at wood steel interface changed bond behaviour significantly. It was observed that bond strength of adhesive bonded wood filled steel tube was 2.58 times greater than that of mechanical bonded wood filled steel tubes. Ó 2019 Elsevier Ltd. All rights reserved. Selection and peer-review under responsibility of the scientific committee of the 10th International Con- ference of Materials Processing and Characterization. 1. Introduction In wood filled steel tube bonding between wood and steel is due to simple interlocking effect between two surfaces. Steel tube is providing framework to hold wood press fitted inside. The mechanical gripping of wood by steel tube is sufficient to cause effective reinforcement. This bonding is efficient in load transfer when applied force is parallel to wood-steel interface. Surface roughness also contributes to the bond strength. Mechanical bond- ing is low energy bonding vis a vis adhesive bonding. Pullout and push out tests measure interfacial characteristics. They frequently result in peak load corresponding to fiber/matrix debonding and frictional load corresponding to the fiber pull out from matrix. The mechanics of pullout tests are complicated [1– 4]. In pullout test fiber is pulled out of the matrix in tensile testing machine and a load vs. displacement record is obtained to study the characteristics bond. There are two mechanisms through which bonds develop at interface of matrix and fiber, namely mechanical (i.e. interlocking) and physiochemical (adhesion and friction) [5]. Series of experimental pull-out tests were carried out [6] using different types of steel fibers with inclinations extracted from various matrix to study the effect of anchorage. It is observed that fiber inclination affects fiber pull-out strength and leads to fiber breakage. Interfacial bond strength of steel rein- forcing bars embedded in high performance fiber-reinforced cementitious composite to study the effect of heating temperature and observed that bond strength decreases with heating tempera- ture [7]. Statistical analysis shows that the interfacial interaction of carbon fiber/epoxy composites could be significantly reinforced with microwave heating to increase interfacial shear strength [8]. Good interfacial bonding is essential to ensure efficient load trans- fer from matrix to reinforcement which helps to reduce stress con- centration and improves overall mechanical properties [9]. There are many experimental results from pull out tests. The wood filled steel tubes are getting evolved various structural applications [10–14]. Hence bond strength studies of wood-steel interface in such applications are require to be conducted to understand bond behaviour and strength. The main objective of this experimental investigation is to understand behaviour of bonding between the wood-steel inter- faces in wood filled steel tubes and evaluate the bond strength. 10 mechanical bonded and 10 adhesive bonded specimens were prepared and pull out tests were carried out on universal testing machine. It is observed that use of adhesive at interface signifi- cantly enhances the bond strength and mechanism of bond behaviour. https://doi.org/10.1016/j.matpr.2020.02.512 2214-7853/Ó 2019 Elsevier Ltd. All rights reserved. Selection and peer-review under responsibility of the scientific committee of the 10th International Conference of Materials Processing and Characterization. ⇑ Corresponding author. E-mail address: bharatesh23@gmail.com (B. Adappa Danawade). Materials Today: Proceedings 26 (2020) 2395–2399 Contents lists available at ScienceDirect Materials Today: Proceedings journal homepage: www.elsevier.com/locate/matpr