Experimental Study On Basic Mechanical Properties Of Basalt Fiber-Modified Clay Lime Mud Brick Masonry

Before the large-scale use of cement,clay lime slurry was widely used as a raw material-rich and low-cost cementitious material.At present,there are a large number of blue-brick masonry structures in China that use clay-lime slurry as a cementitious material.Since there is no specification for such buildings,their seismic performance is unknown.Therefore,the mechanical properties of such cementitious materials and the use of this kind of The mechanical properties of masonry structures built with cement-like materials have become a top priority.Clay lime slurry is a mixed cementitious material with certain plasticity that is mixed with clay and slaked lime without adding any aggregates and modified materials,and then directly mixed with water.In this paper,clay and calcium hydroxide are used as raw materials to prepare clay-lime slurry,and basalt fiber is used to modify it with performance enhancement as an innovation.In this paper,the mechanical properties of clay-lime slurry and modified clay-lime slurry under the influence of different volume ratios are studied,and the curing reaction mechanism is analyzed through microscopic experiments.The mechanical properties of the masonry structure were concluded as follows:（1）In the mechanical properties test of clay-lime slurry,the maximum compressive strength and flexural strength can be obtained when the volume ratio of clay and slaked lime is 1:1;the maximum tensile strength can be obtained when the volume ratio of clay and slaked lime is 1:2.value.（2）In the microscopic test,the hydration reaction of the sample with a volume ratio of clay-lime slurry of 1:1 is the most complete,and its 28d hydration product is mainly C2ASH8 hydrated kaffirite,and the XRD diffraction peak and FTIR absorption peak of the corresponding position In the SEM observation,the microstructure of the samples with a volume ratio of 1:1 is denser than that of the samples with other volume ratios.（3）In the research on the compressive and tensile properties of basalt fiber-modified clay lime slurry,the maximum compressive strength can be obtained when the basalt content is 0.3%,and the flexural strength and flexural strength can be obtained when the basalt content is 0.2%.The maximum tensile strength,when the fiber content is greater than or equal to 0.6%,the compressive,flexural,and tensile strengths of the modified clay-lime slurry decreased significantly.（4）In the shear test of the masonry structure through joints,whether it is the three-brick method or the nine-brick method shows the same law,that is,the shear strength increases with the increase of the volume of slaked lime;in the compressive test of the masonry structure,when the volume ratio of clay and slaked lime is 1:1,the maximum compressive strength of masonry can be obtained;the shear resistance and compressive properties of masonry structures built with modified clay-lime slurry are enhanced to a certain extent.（5）By comparing the shear strength data of the three-brick method and the nine-brick method and performing linear fitting,it is concluded that the shear strength of the three-brick and the nine-brick method has a strong correlation;by analyzing the compressive and shear strengths Combined with the data in GB50003-2011 "ode for Design of Masonry Structures",the formula of the average shear strength and design value of the clay lime mortar blue brick masonry structure was deduced.