Study On Impact Performance Of Basalt Fiber Reinforced Concrete Under Low Temperature

As it is known,concrete is one of the most widely used building materials in modern architectures.However,in civil engineering,all kinds of concrete structures inevitably encounter dynamic load during the design lifetime,except in the case of static load.For example,ocean flats encounter impacting of ocean waves,airport runways must withstand repeated dynamic loads due to aircraft takeoff and landing,protective structures subjected to projectile or aircraft impact,and structures sustaining impact loads during earthquakes.Dynamic loads(such as those loads)can cause the damage and collapse of buildings,which can lead to casualties and property losses.Because of their unpredictability and destructive capacity,these kinds of loading always become important factors in controlling structural design.In addition,the impact resistance is a very important parameter for evaluating the dynamic performance of concrete,thus it is very necessary to study concrete under impact load.The impact resistance of basalt fiber reinforced concrete in low temperature environment was measured using U-shaped concrete specimens in a drop-weight test.The Basalt fibers of 15μm diameter used in the test were of two different lengths(6mm and 18 mm)and four different volume fractions including 0%,0.4%,0.6%and0.8%.The statistical analysis and probability of failure of the test results were analyzed by Weibull distribution.The analysis results indicate that the impact resistance of the basalt fiber reinforced concrete can be statistically analyzed by the Weibull distribution.The natural logarithm of initial and final crack impact frequency is used to evaluate the impact resistance of basalt fiber reinforced concrete.On the condition of the equal failure probability,the impact resistance of basalt fiber reinforced concrete is in proportion to the content of basalt fiber.The basalt fiber reinforced concrete with 18 mm diameter fiber performs better impact resistance than that with 6 mm diameter fiber,when the equal volume of fiber is used.