URM Building Retrofit Applications
Explore Retrofit Applications
Lateral Shear Resistance
Where existing walls lack sufficient shear strength to resist seismic loading, a traditional reinforced shotcrete method may be utilized to increase the in-plane shear strength of URM structures. Although effective, this method takes up space and adds a lot of weight to the structure which increases the seismic load on the structure. An option for increasing the in-plane shear strength of the URM wall assembly, without significantly increasing the structure weight and adding to the seismic demand, is to utilize Fiber Reinforced Polymer (FRP) material.
Special detailing is required when attaching an impermeable element, such as FRP, to a porous URM wall.
Another option is to use Fabric-Reinforced Cementitious Matrix (FRCM). FRCM consists of a carbon grid which is adhered to the existing wall with a cementitious matrix. Although installation is similar to shotcrete, the layers are much thinner and no rebar is required resulting in a quicker and lighter installation.
In areas where there is little wall space (such as retail frontage with large openings), one should consider the installation of a Special Moment Frame (SMF). These frames can be designed to resist large forces and have minimal impact on open space.
Simpson Strong-Tie Products for Lateral Shear Resistance

AT-XP® is a fast-cure, all-weather, high-strength anchoring adhesive and may be used to anchor threaded steel rods or deformed steel reinforcing bars in unreinforced masonry.
AT-XP High-Strength Adhesive
ET-HP® is an epoxy-based system for use as a high-strength, non-shrink anchor-grouting material and may be used to anchor threaded steel rods or deformed steel reinforcing bars in unreinforced masonry.
ET-HP Epoxy Adhesive
Screen tubes are used in hollow base material applications to contain adhesive around the anchor and prevent it from running into voids.
Steel Adhesive-Anchoring Screen TubesThe Heli-Tie helical wall tie is a stainless-steel tie used to anchor building façades to structural members or to stabilize brick walls. The Heli-Tie helical stitching tie provides a unique solution to the preservation and repair of damaged brick and masonry structures.
Helical Wall and Stitching Ties
FX-263 Rapid-Hardening Vertical/Overhead Repair Mortar is a cementitious, single-component, fiber-reinforced, polymer-modified, silica fume-enhanced, structural repair mortar with integral corrosion inhibitor designed for vertical and overhead applications.
FX-263 Repair MortarThere are a number of epoxy solutions that may be used to repair structural concrete and masonry that cover a wide range of crack widths and applications.
Structural Epoxy RepairComposite Strengthening Systems (CSS) provide efficient solutions for the structural reinforcement and retrofit of aging, damaged or overloaded masonry structures.
Composite Strengthening SystemsThe Yield-Link® special moment frame connection provide optimal moment transfer solutions for both new and retrofit projects. Our Yield-Link structural fuse technology ensures the resilience of the frame during seismic events.
Yield-Link Special Moment Frame