Experimental Study On Compression And Seismic Performance Of Perforated Brick Masonry Strengthened With HPFL

Perforated brick has features such as saving energy, saving land resources, lightweight and good heat insulation,etc, which is a new wall materials having developedwith wall material innovation. Since the1950s, our country has been encouraging touse perforated brick. There are many perforated brick masonry in Chinese cities and ruralarea. Perforated brick is produced by vacuum extrusion production process, so that ithas high strength and more brittleness than solid clay brick. In the process of buildingand using, there are variety of reasons which could cause perforated brick masonryunsafe, especially that in rural areas most perforated brick masonry buildings haven’tseismic fortification measures and are easily damaged even collapsed in earthquake.The fact gave us a painful lesson that there are large numbers of perforated brickmasonry collapsed in Tangshan earthquake in1976. Therefore, looking for a kind ofeconomic and effective reinforcement perforated brick masonry method has the vitalsignificance.High-Performance Ferrocement Laminate(HPFL) is used more and more widelyas a new reinforcement method which has advantages such as good effect, littleinfluence to original structure, low expenses, good durability and convenientconstruction. We had done the axial compression and pseudo-static testing of theHPFL reinforcement perforated brick masonry to research the effect of thereinforcement.First of all, we putted three group reference specimens and five groupstrengthened specimens (a total of24) to the axial compression tests, and did thecomparative analysis the specimens’ test results such as the failure process and form,compressive capacity, crack load and stress strain curve, etc. The test results showthat: the reinforcement method with HPFL can effectively increase the crack load andcompressive capacity of perforated brick masonry, improve the brittleness, improvethe ability of deformation and ductility of perforated brick masonry. On the basis ofthe theoretical analysis and test results, we fitted the calculation formula of thecompressive capacity of perforated brick masonry strengthened by HPFL.Then, we did the pseudo-static testing of one group reference specimens and fivegroups specimens strengthened by HPFL (a total of12pieces wall),and did thecomparative analysis the specimens’ test results such as the failure process and form,seismic shear capacity, crack load, the horizontal displacement of the wall crown，hysterrisis curve and stiffness degradation curve, etc. The test results show that: the reinforcement method with HPFL stripe can effectively increase the seismic shearcapacity of perforated brick masonry. The seismic shear capacity and rigidity of thespecimens strengthened by HPFL scissors-brace were significant improved, but theirdeformation capacity, ductility and energy dissipation capability improved little. Theincreases of the seismic shear capacity of the specimens strengthened by HPFLstructural column-ring beam are less than those strengthened by HPFL scissors-brace,but the deformation capacity, ductility and energy dissipation capability of thespecimens strengthened by HPFL structural column-ring beam were very signallyimproved. Finally, On the basis of the theoretical analysis and test results, we fittedthe calculation formula of the seismic shear capacity of perforated brick masonrystrengthened by HPFL. The results of the formula calculation coincide with the testresults. The formula can be reference for the strengthening engineering design.