Unreinforced masonry is the construction system of most of historic structures and a
considerable percentage of existing residential buildings in Egypt. One of the important
disadvantages of unreinforced masonry construction is its low resistance to tensile stresses and
lateral loads, so there is frequently need for appropriate strengthening for such structures. Fiber
reinforced polymer (FRP) composites have been successfully applied as externally bonded
reinforcement for strengthening of reinforced concrete and masonry structural elements as well.
Their excellent strength-to-weight ratio and easy installation make them an attractive alternative for
traditional strengthening methods.
This paper presents experimental investigation of strengthening masonry walls and vaults
using FRP composites, as well as other traditional methods such as steel reinforcement bars, ferrocement
layers and polymer mortar layers. The experimental program is explained and the maximum
capacity and failure mode associated with each strengthening technique are presented and compared.
The experimental results showed that FRP gave higher strengthening level and better failure mode
than using traditional steel reinforcement bars or ferro-cement layers. Use of glass fiber composites makes it also as cheap as other techniques. Using polymer mortar was the least effective technique.
Also, strengthening of masonry wall specimens using confining FRP layer was found to be a very
efficient method, where the failure load was double that of the unstrengthened specimens. |
