Test And Theoretical Research On Antiseismic Behavior Of Masonry Structure With Thermal–insulation Sandwich And Core Columns Inside

Rural houses are required to be low in cost and good in anti-seismic behavior and thermal-insulating performance, and therefore how to design a low-cost anti-seismic and energy-saving rural house structure has always been an urgent issue and received a lot of attention in the engineering circle. In this dissertation, The paper presents a omposite masonry structure with thermal-insulation sandwich and core columns inside. In this structure, bricks were inlaid with fly ash blocks to achieve the thermal-insulation performance, and core columns were arranged in sandwiches of the wall; the core columns were made from timbers,square steel tubes or circular steel tubes; the bricks were made of clay bricks or recycled bricks,using clay brick and recycled brick as the material of brick. The brick walls, core columns and the thermal-insulation blocks work together to bear the vertical load and resist the horizontal earthquake action. In order to study the anti-seismic behavior of the novel composite masonry structure, systematical experimental and theoretical analysis was carried out. The main contents and contributions are as follows:1. The composite masonry structure with thermal-insulation sandwich and core columns inside was proposed; sixteen specimens with different test parameters were tested under axial compression load; the“load-deformation”curves were compared; the bearing capacity, the damage characteristics and the compressive deformation process were analyzed; the corporative working mechanism of the core columns and bricks was revealed; the compression bearing capacity computation formula of the brick masonry was obtained, and the calculated results fit the test results well.2. The low cyclic loading test on three typical specimens of brick masonry structure with thermal-insulation sandwich and core columns inside was carried out. In the test, tis novel wall technology was combined with the glass beads-graphite foundation seismic isolation and deformation limit device technology proposed by our research group. Each specimen was provided with upper and lower foundation beams, and the places between the upper and lower foundation beams were paved with the glass beads-graphite. After the lower foundation beams were fixed, the walls were in the elastic state before the upper …were slid to the limited state, and then the anti-seismic behavior test was started. The “Load-Deformation” curves in the anti-seismic isolation phase werecompared; the bearing capacity, the damage characteristics, the ductility and hysteretic behavior were analyzed; the proportional relation between the isolation starting load and ultimate load was obtained; the inherent law about how the core columns and bricks cooperate to enhance the seismic behavior was revealed; the shear bearing capacity computation formula of the brick masonry was obtained, and the calculated results fit the test results well.3. Based on the test, further theoretical study was conducted. The study includes the finite element modeling, the FEM analysis of the compression behavior, the strain-stress characteristics, and optimization of the design parameters.4、The anti-seismic design method and construction measures of the brick masonry structure with thermal-insulation sandwich and core columns inside were proposed, this new structure was applied to the real construction and the application effects turned out to be good.Main conclusions:(1) The seismic isolation masonry structure with glass beads-graphite has the advantages of low cost, easy construction and stable behavior, the slippage can be started under low load, and the effects proved to be good.(2) The clay bricks, recycled concrete bricks, clay bricks-fly ash blocks and recycled concrete bricks-fly ash blocks were similar in the compression damage progress, all in a typical brittle damage manner. While as to the specimens with built-in timbers, square steel tubes and circular steel tubes, the compression capacity and ductility can be obviously enhanced.(3) In the brick masonry structure with thermal-insulation sandwich and core columns inside, bricks were inlaid with fly ash blocks to achieve the thermal-insulation performance, and light steel tubes were built in the wall sandwiches to achieve the anti-seismic effect. The bricks were used the clay bricks or recycled brick. The brick walls, core columns and the thermal-insulating blocks can work together to bear the vertical load and resist horizontal earthquake. The shear resistance and seismic behavior were enhanced compared with the common brick walls.(4) As a new thermal-insulation and load-bearing wall structure, the brick masonry structure with thermal-insulation sandwich and core columns inside has good thermal-insulation performance and integrated anti-seismic behavior and energy-saving function, and can be applied to be used in the anti-seismic and energy saving house design in the rural area. The construction measures, the calculation model of load bearing capacity and design method can be used as a reference in the real design work.