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))