Page 449 - Advanced Design Examples of Seismic Retrofit of Structures
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Examples of Nonengineered Buildings Chapter  6 395


             approach which was proposed by Tolles et al. [5] attempts to mobilize adobe’s
             favorable post-cracking, energy-dissipation characteristics while limiting rela-
             tive displacements between adjacent cracked blocks. The purpose of this
             approach is, while accepting a level of damage in moderate to high earthquakes,
             to prevent severe structural damage and collapse. Thick adobe walls are inher-
             ently stable and have great potential for absorbing energy. These stability and
             energy-absorption characteristics can be enhanced by the application of a num-
             ber of simple seismic improvement methods, as described in the following
             section.


             6.3 RETROFIT METHODS
             In this part, a brief review is made on the commonly used retrofit methods for
             seismic performance improvements of adobe buildings around the world. The
             more comprehensive review on various retrofit methods for masonry construc-
             tion can be found in Chapter 2.

             6.3.1 Bond Beam on Top of the Walls

             Perhaps the most widely proposed method of strengthening adobe houses is the
             placement of bond beams in the upper perimeter of the walls [7] (Fig. 6.4) and
             confinement [8], as shown in Fig. 6.4. Nonetheless, this method requires severe
             intervention and sophisticated execution for the existing buildings, which
             makes it suitable for construction of new earthquake-resisting houses, not as
             a retrofitting solution.


             6.3.2 Mesh on Walls Surfaces
             Reinforcing adobe walls with mesh grids has proved an effective technique for
             seismic retrofit of adobe buildings in the past earthquakes and by many


















             FIG. 6.4 Construction of bond beam. (Permission from Ms. Rachel Chapman (Ethnos 360))
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