ABSTRACT
This chapter describes several solutions and the most promising one are tested on a smaller scale in bending using wallettes and larger inplane loaded walls. Worldwide several materials and techniques are being used to improve the seismic performance of existing unrein-forced masonry walls. These include: stitching and grout/epoxy injection, re-pointing, bamboo reinforcement, post-tensioning using rubber tires, and various types of mesh reinforcement. The strengthening process starts by milling deep and shallow grooves with a pre-calculated center to center distance, based on the required seismic strengthening of the building. The majority of buildings in the North-East of the Netherlands is composed of unreinforced single leaf masonry, only designed to withstand wind loads. The challenge is to find and develop a suitable seismic retrofitting system for the single leaf masonry buildings in Groningen. In Groningen, an area in the North-East of the Netherlands, earthquakes occur as a result of the subsidence of the ground at relatively shallow depth beneath the earth's surface.
