| In recent years, China has been vigorously carrying out a reform for wall materials. Solid clay bricks are forbidden to be used and new wall materials are being developed. In this respect, China is going toward the direction of being environmentally-friendly. In accord with the state policy, baked bricks made from non-clay materials such as coal gangue, fly ash and others have been promoted for extensive applications. Especially coal gangue combining solid, fluid, gaseous industrial waste will become a new engine for economic growth through waste recycling. It will benefit economy, environment and society. The extensive application of coal gangue perorated bricks can not only solve the environmental pollution caused by tons of coal waste from coal mines but also contribute greatly to energy conservation in China's domestic architecture.In the Design of Masonry Structures, there are inadequate experimental studies and data about this new type of building material. The application of the original data from the experiment concerning the clay bricks cannot match the material requirements of the coal gangue porous bricks, especially in the construction of the seismic fortification. In order to improve the seismic performance of the masonry of new building material, particularly the deformability in the earthquake, to make the coal gangue bricks of new building material safely and widely used, and to enrich the Design of Masonry Structures with more reliable scientific basis, this issue studies the bond anchorage mechanism and bond stress distribution of the rebar and proposes its anchorage length in the ash crack of porous bricks through pull-out experiment.Based on the full understanding and master of the foreign and domestic theories and experiments of bar anchorage, testing programs were planned and samples were made in this program with reference to relevant articles and materials. After the accomplishment of the testing programs, a theoretical analysis was made based on the results of the testing programs with a method similar to that of studying the bar anchorage in reinforced concrete structure. Experiments were done on the basis of the analysis in order to make out the working mechanism. To make a comparison, other research results were studied as a reference and thus the general law was deduced. Finally, finite elements simulation was done according to the results using the finite element software.The contents of this thesis are as follows:1. Theoretical Analysis: Through the bonding mechanism of steel bars and concrete, the bonding and anchoring mechanism of steel bars and mortar is analyzed; according to the anchorage formula of the reinforced concrete, for the staight steel bars with no hooks, conclude the anchorage length formula of of steel bars in the ash crack of the masonry joints is concluded.2. Through test, the impact of normal stress, anchorage length, diameter of the steel bar and mortar intensity on the cohesion of steel bars and its degree are analyzed. The features of destruction, its mechanisms and causes by comparative analysis of destructive cohesion of coal gangue perorated bricks with square holes and that with round holes are analyzed.3. The average cohesion and limit anchorage length of steel bars through analysing the result of test are calculated. The approximate anchorage length of steel bars, which meet the current specifications, in structures built by perorated bricks by reliability theory is calculated. Analyse the impact of construction factors on the anchorage of steel bars, and propose the anchorage length to meet the engineering requirements.4. Based on the test, using ABAQUS finite element analysis software, it was carryed out finite element simulation, then further analyze the mechanical properties between the steel bars and the masonry.Finally, the paper summarizes the work and put forward the future research.
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