Preparation And Properties Of Fiber Bead Chain Reinforced Cementitious Composites

A new way of fiber reinforced cement products---Fiber bead chain reinforced cement products is put forward in the subject.Its preparation method is that: First,the continuous fiber is made into fiber bead chain,That is,the resin is dropped to continuous fiber on the specific length,the fiber-resin bead chain is made after resin curing,Bead chain of a specific length is taken and then it is paved into slurry layered directionally according to specific laws in the process of filling the slurry.The way of fiber bead chain reinforcement can solve the problem of fiber content restricted in fiber reinforced concrete at this stage,the working performance of concrete becomes worse and the mechanical property declines when a large amount of fiber is added.It can also solve the problem of poor interfacial properties between fiber and cement,fibers tend to slip and cannot coordinate with the cement matrix when fiber reinforced cement products are subjected to external forces.This subject explores the fundamental reason why traditional fiber reinforcement methods can not improve the mechanical properties of composite materials effectively.The agitated short fiber reinforced mortar slurry and the short fiber reinforced mortar section at the end of initial condensing were observed through ultra depth microscope.Results found: The short fiber is distributed disorderly in the paste and some fibers are not effectively wrapped up by the slurry,The phenomenon of aggregation of fibers often appear.There is obvious weak interface between fiber and cement matrix after mortar forming.there is obvious weak interface between fiber and cement matrix after mortar forming;The internal force distribution of fiber reinforced concrete under external force is simulated by ANSYS.Results found: Fiber reinforced concrete has high shear stress concentration at both ends when subjected to external force,This is the main reason why fibers tend to slip and cannot coordinate with matrix deformation.The conclusion is drawn through through the working performance and mechanical properties comparison between glass fiber reinforced cement-based composites and basalt fiber reinforced cement-based composites under three kinds of fiber reinforcement methods: By the method of laying the fiber into the slurry layered directionally,the fiber is distributed evenly in the slurry,therefore the fiber bead chain enhancement technology improves the fiber content in the fiber reinforced cement matrix composite;It can also solve the interface weakness problem of fiber reinforced concrete through mutual fixation between bead and cement matrix which changes the interface constraints between two-phases into structural constraints.When the volume fraction of fiber is 1%,Compared with the benchmark group mortar,the glass fiber bead chain reinforced mortar 28 days flexural strength increased by 202% and the compressive strength increased by 50%,the basalt fiber bead chain reinforced mortar 28 days flexural strength increased by 204% and the compressive strength increased by 17%,The crack resistance of two kinds of fiber reinforced mortar has been significantly improved.Compared with the benchmark group concrete,the glass fiber bead chain reinforced concrete 28 days flexural strength by 121% and the compressive strength only decreased by 8%,Concrete cracks were small when concrete was destroyed,the higher flexural strength was achieved at early stage and the long-term growth of compressive strength did not be affected.So it can be informed of that: Although there are differences between two kinds of fiber material characteristics,between mortar and concrete aggregate composition,fiber bead chain reinforcement technology is not only suitable for glass fiber reinforced cement-based composites,but also for basalt fiber reinforced cement-based composites;It significantly improves the mechanical properties of cement mortar,but also performs well in concrete;Only by raising 10% of the total cost,the various mechanical performance of the test piece can be improved.Therefore,the technology of fiber bead chain reinforcement is practical,feasible and Good prospects for development.