Contents lists available at ScienceDirect Structures journal homepage: www.elsevier.com/locate/structures Assessment of axial load carrying capacity of GFRP funicular shells with steel mesh Khalid Bashir a, ⁎ , Arif Ahad b , P. Sachithanantham b , Chaidul Haque Chaudhuri c a Department of Earthquake Engineering, Indian Institute of Technology Roorkee, Uttrakhand 247667, India b Department of Civil Engineering, Bharath Institute of Higher Education and Research, Chennai, Tamil Nadu-600073, India c Department of Civil Engineering, Indian Institute of Technology Bombay, Maharashtra-400076, India ARTICLEINFO Keywords: Funicular shells GFRP Failure loads Specimens Rise ABSTRACT This paper presents the test results of an experimental program to investigate the load-bearing capacity of twenty-seven Glass Fibre Reinforced Polymer GFRP funicular shells under pure compression load. The test parameters include the number of glass fiber layers, the rise of shells and the effect of inclusion of steel mesh as an additional reinforcement to the glass fiber. Comparisons between the experimental test results of various parameters are performed in terms of the ultimate load-carrying capacity. A parametric study was conducted which showed the significant effect of the increasing rise on the load bearing capacity of GFRP shells. In general, the results of this study revealed that the ultimate load-carrying capacity gets increased by nearly 58% by increasing the number of normal glass fiber layers from two to four. Moreover, an increase in the ultimate load- carrying capacity of nearly 15% to 26% was observed with the inclusion of steel mesh as an additional re- inforcement to the glass fiber. In the latter case, the deflections were comparatively lesser than the former. The failure loads of all the specimens were found and two equations were proposed to express the relation between rise, span to rise ratio, with ultimate load. It is concluded that the ultimate loads are a function of the rise of the shell and the number of fiber layers. The addition of steel mesh increases stiffness of shells, there by reduces total deflection. 1. Introduction Shells belong to the class of stressed skin structures which, because of their geometry and small flexural rigidity of the skin, tend to carry loads primarily by direct stresses acting in their plane. In the design of new forms of composite shell structures, the conventional practice is to select the geometry of shell first and then making the stress analysis. Hence it is advantageous to select the shape of shell in such a way that, under this condition of loading, the shell is subjected to pure com- pression without bending. “Shell structures are widely used in the fields of civil, mechanical, architectural and marine engineering” [1]. Several researchers [24,23,25,28] have reported that shells are usually lighter in weight, economical and from aesthetic point of view more superior than other type of structural shapes. Based on earlier researches [25,17] it has also been revealed that funicular shells having a negligible bending effect. Instead of bending, load is transferred through axial forces. Vafai [23,24] conducted a study on pointed domes loaded at vertex. Vafai [25] studied the behavior of concrete funicular shells subjected to vertical loads. Weber [28] studied the effect of rise and reinforcement on the ultimate load-carrying capacity of concrete shallow funicular shells. It was seen that with the increase in rise and thickness of the shell, the load-carrying capacity increases. Analytical and experimental studies carried out by Vafai [1] on concrete funicular shells subjected to concentrated point load at the apex revealed that with an increase in the rise of shell ultimate load-carrying capacity also gets increased. As per the author’s knowledge, there has no study been carried out to study the behavior with GFRP and the effect of steel mesh as reinforcement within the fiber layers on ultimate load-carrying ca- pacity. Several other researchers Ramaswamy [15], Ramaswamy [16], Farshad [5] and others, have studied the potential use of shells in construction. Almost all the past studies are based on concrete shells no study on GFRP shells has been done as per the author's knowledge. “Shells of different material, size and shape usually in metal, concrete and composite materials are used for many different structural pur- poses” [1]. Many older structures of national importance, usually constructed in domes or shells can be seen worldwide. Many structures https://doi.org/10.1016/j.istruc.2019.12.013 Received 13 May 2019; Received in revised form 28 November 2019; Accepted 9 December 2019 ⁎ Corresponding author. E-mail addresses: kbashir@eq.iitr.ac.in (K. Bashir), er.arifahad@gmail.com (A. Ahad), sachugcivil@gmail.com (P. Sachithanantham), chaudhuri.ch@iitb.ac.in, chaidul.kdl@gmail.com (C. Haque Chaudhuri). Structures 24 (2020) 974–983 Available online 14 February 2020 2352-0124/ © 2019 Institution of Structural Engineers. Published by Elsevier Ltd. All rights reserved. T