Abstract:
The structural rehabilitation of historic/traditional rubble masonry wall constructions
requires consolidation and retrofitting solutions to be employed in order to withstand dynamic loads,
high vertical loads, and differential settlements. One of these strengthening techniques is based
on the use of steel bar connectors perpendicular to the wall, considered individually or integrated
into more complex strengthening techniques. The aim of this study is to evaluate numerically the
strengthening effect of transverse steel connectors on rubble masonry walls. With this purpose, a 2D
particle-reinforced model (2D-PMR) was devised and applied to model uniaxial compression tests.
The results presented show that predictions calculated using the proposed 2D-PMR model are very
close to known experimental results, particularly in the corresponding failure modes, the increase of
the maximum uniaxial compression value, and ductility. Parametric studies are also conducted by
varying the diameter of the steel bars and the level of strengthening to assess the influence of the
bar-bond effect and lateral plates. The presented parametric numerical studies show that (i) a two-
level strengthening solution guarantees a similar response to the three-level strengthening solution
adopted in the experiments; (ii) it is not relevant to apply a grout injection during the application
process of the steel connectors if lateral plates are adopted; and (iii) the 2D-PMR model can be used
in the definition of the steel bar diameter and properties; as shown, a smaller (8 mm) bar diameter
predicts a similar strengthening effect to the (12 mm) bar size adopted in the experiments. Given the
performance of the proposed 2D-PMR model, further work is underway that will allow the 2D-PMR
model to numerically assess other reinforcement techniques, namely, reinforced micro-concrete layers
and textile reinforced mortar.
