The results of the tests on two masonry specimens in tuff elements bonded by pozzolanic mortar and retrofitting by jointed jacket, in unfavourable conditions, are described. The first test is deruled on originally wall «no jacket», by monotonic shear charge below limit service normal stress. The second test is evolved by cyclic quasi-static shear on masonry improvement with «jointed jacket» steel grid of the limitated surface and no blinded with adjacent ones, connected by tightening bolts for induced triaxial strength.
Emphasize the isotropic and homogeneous behaviour of the original masonry, in the service state limit in sintony to similar constitutive bond mortar/tuff; in particular the mortar resistance is measured by a new in situ torsional test compared with traditional test. The analysis of experimental data is developped principally by eurocode EC6 for masonry. The stiffness of fissured jacked wall is similar original masonry, and ultimate shear is 40% superior to original monotonic cracking test. The return to the pseudo elastic behaviour after improvement the first cracking, is emphasized from the absence of the permanent displacement and reduced isteretic phenomena in cyclic service state limit, while increase toward the ultimate limit state. The important role in bearing capacity of the friction Coulumbian model and specially cohesion value is back analysed from SLU and SLE before parzialitiation of the wall section, in particular in presence of the foundations settlements and revolution of the collapse moment/shear mechanism.
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