Proposed Shear Strength Calculation Method On Perforated Brick Masonry Along Through Joint Under The Action Of Shear And Compressive Stress And Test Validation

After the wall’s reform policies implemented limit clay brick and solid brick wall isprohibited in China, perforated brick masonry structure become one of the main structuresinstead of solid clay brick masonry. In order to explore the mechanical mechanism ofperforated brick masonry shear composite, seeking through joint shear strength calculationmethod for the study.From through joint of perforated brick wall passed ladder （including dentate crackfailure） feature to make reason analysis, then puts forward the shear strength hypotheticalcalculation formula under the action of shear-compressive stress. Analysis the imaginaryformula of parameters and design experiments to measure the specific values.Constructedtest wall as the same requirements as the actual wall. Tentative cutting method to find thecutting line from the mortar joint suitable distance of the upper and lower edges, then cutthe wall with cutting machine. Statistics mortar cotter efficient η from the cutting sectionof round and rectangular hole of perforated brick wall. Designed three brick-two boardmortar key shear specimen which were only complete mortar keys without the interferenceof the shear component of the contact surface’s mortar and the mortar key force close tothe state of pure shear. Through a total of12shear specimen of mortar key of two passmeasured shear strength τ_ssof round and rectangular hole perforated brick masonry. Andfound that the round hole brick specimen shear strength τ_ssthan the rectangular hole brickspecimen. Designed a14brick shear-pressure resist shear specimen which simulated240mm thick brick wall and the specimen constructed in such a manner in accordancewith a cis-1Ding construction. The specimen ensured the middle brick and mortarcompletely in a state of uniform compression in the axial pressure. Through a total of48shear-pressure specimen of two pass measured shear strength τ₂of round and rectangularhole of perforated brick masonry. The shear-pressure specimen test also found that the gapis narrowing between τ_y2mand τ_j2m, when the axial compression ratio improved. Doubleshear failure of the specimen was significantly more than the number of single shearspecimen, but does not affect the final result. These reasons are all proven. With solidbrick test fitting formula replace the same shear nature of the entity mortar shear strengthτ_szto arrive at the proposed formula. Revise the basic type of calculation results τ_1mwiththe measured average value of shear-pressure composite shear strength τ_2mof perforatedbrick masonry. Obtain adjustment coefficient λ is0.7, and then get shear strength formulaof perforated brick masonry of through joint under shear-pressure composite. A total of12mortar keys shear specimen by two grooved test values are substituted into the proposed formula, which to compare the experimental results with the24composite shearspecimens. Preliminary tests verified the proposed formula calculation results are reliable.Hope the study of test methods and superficial conclusions can be widely discussedin order to further explore porous brick masonry shear mechanism to provide thereference.