Experimental bond behaviour of GFRP and masonry bricks under impulsive loading

Abstract

Fibre Reinforced Polymers have become a popular material for strengthening of masonry structures. The performance of this technique is strongly dependent on the bond between the FRP and the substrate. Understanding the strain rate effect on these materials and strengthening techniques is important for proper design and proper modelling of these systems under impacts or blast loads. This work aims to study the behaviour of the bond between GFRP and brick at different strain rates. A Drop Weight Impact Machine specially developed for pull-off tests (single shear tests) is used with different masses and different heights introducing different deformation rates. The strain rate effect on the failure mode, shear capacity and effective bond length is determined from the experimental results. Empirical relations of dynamic increase factors (DIF) for these materials and techniques are also presented.

The Bond-Slip Relationship at FRP-to-Brick Interfaces under Dynamic Loading

“…The dynamic FRP stiffness and dynamic brick strength at a given slip rate can be calculated by combining Equations ( 9), ( 10) and (13). Then, the bond-slip parameter at a given slip rate can be calculated by substituting the dynamic FRP stiffness and dynamic brick strength into the empirical formulas (11) and (12). The maximum bond stress and the corresponding slip calculated by the empirical formulas were compared with the test and numerical results.…”

“…The masonry structure is likely to be subjected to dynamic loads such as earthquakes, explosions and impacts. Experimental studies of the FRP-to-substrate interface show that the dynamic interfacial strength is significantly higher than that of static [ 10 , 11 , 12 , 13 ], and the dynamic bond–slip relationship is naturally different from that of static [ 14 , 15 , 16 , 17 , 18 ]. An accurate bond–slip relationship can be used for strength calculations of FRP-reinforced structures, helping to design safer and more economical FRP-reinforced solutions.…”

Computational Applications in Masonry Structures: From the Meso-Scale to the Super-Large/Super-Complex

“…Experimentation is, in the field of fast dynamics, still at a higher level with respect to numerical modeling (Buchan and Chen 2007). Some laboratory tests have been performed to evaluate the response of the masonry under such extreme loads, see for (Pereira and Lourenço 2016b;Pereira et al 2015;Pereira and Lourenço 2016a;Hao and Tarasov 2008;Dennis et al 2002;Baylot et al 2005). In converse, few numerical studies on the response of masonry under blast or impact actions are found in the literature; one may recall the contributions by (Wu et al 2005;Zapata and Weggel 2008;Macorini and Izzuddin 2014;Burnett et al 2007).…”

Global database of FRP-to-masonry bond strength tests

“…Through an extensive literature review, an experimental database of 1583 individual shear pull-tests on masonry specimens was compiled from across 56 published studies [1] , [2] , [3] , [4] , [5] , [6] , [7] , [8] , [9] , [10] , [11] , [12] , [13] , [14] , [15] , [16] , [17] , [18] , [19] , [20] , [21] , [22] , [23] , [24] , [25] , [26] , [27] , [28] , [29] , [30] , [31] , [32] , [33] , [34] , [35] , [36] , [37] , [38] , [39] , [40] , [41] , [42] , [43] , [44] , [45] , [46] , [47] , [48] , [49] , [50] , [51] , [52] , [53] , [54] , [55] , [56] .…”

“…The data therefore excludes the following: Specimens subjected to effects such as temperature and moisture [5] , [25] , [29] , [33] , [41] , [46] , [51] , [52] ; Tests in which additional anchorage between the FRP and substrate was provided. For example those with nails, fans or cogs [9] , [18] , [24] , [30] , [32] , [55] ; Tests in which the FRP was bonded to plaster instead of directly to the masonry substrate [9] , [39] , [42] , [55] , [56] ; Non-quasi-static loading conditions such as impulse loads [54] ; and Plates manufactured from textile-reinforced mortars or fibre-reinforced cementitious mortars. …”