The objective of this EAGER project is to conduct a proof-of-concept study related to the use of inexpensive, abundant and benign bio-based materials to enhance the performance of concrete that is currently used as transportation infrastructure material. In particular, the research will combine wheat fiber and lignin with cement concrete. Lignin acts as a water reducer controlling the water-cement ratio and improving strength and durability. Wheat fiber, on the other hand, acts as a micro-cracking barrier controlling the microstructure crack growth under early age and fatigue conditions. More sustainable concrete, which exhibits higher durability and higher resilience against cracking and fatigue, will be produced by using agricultural waste materials combined with bio-fuel co-products. The proportions of cellulose fibers and lignin, which optimize the performance of the sustainable concrete under short term loading will be determined.
The research is driven by the ultimate goal to benefit the society. Specifically, the use of inexpensive, renewable and environmentally friendly bio-based materials for improved performance, durability and economy of the transportation infrastructure. One M.S. student along with the PI and Co-PIs will be directly involved in the research. The results of the proposed research will be integrated into education through inclusion of various research findings in undergraduate courses. The proposed research will take place in the state of Kansas, an EPSCoR state, thus broadening the participation of geographically underrepresented regions in scientific research and education.
By: Mohammed Albahttiti, Hayder Rasheed, Dunja Peric and Lawrence Davis Green and sustainable building materials have been on the top of agendas for researchers all over the world. The notion of recycling and using materials from the nature is welcomed in some countries or rather required in others. In order to investigate one of the most common natural materials; wheat fibers, as reinforcement, 156 mortar specimens and 99 concrete specimens were tested. The specimens were tested in either compression or bending. The compression test included 2 in (50.8 mm) mortar cubes and 4x8 in (101.6 x 203.2 mm) concrete cylinders. As for the bending test, they were either 40x40x160 mm mortar prisms or 6x6x21 in (152.4x152.4x533.4 mm) concrete prisms. The main objective of this research was to determine if these natural fibers increase the loading capacity of the specimen tested and what is the optimum amount to do so. Also to compare specimens reinforced by wheat fibers with those reinforced by polypropylene fiber. As a result of these tests the compression loading capacity for 0.5% wheat fiber-reinforced mortar cubes exceeded that of polypropylene-reinforced cubes by 15%. Whereas for the 0.75% wheat fiber-reinforced concrete cylinders; their loading capacity exceeded that of the polypropylene-reinforced concrete cylinders by 5% and that of the control by 7%. The bending capacity of the .75% wheat fiber-reinforced mortar prisms exceeded that of polypropylene-reinforced mortar prisms by 27%. Meanwhile, concrete prisms reinforced with both wheat fiber and polypropylene fiber showed reduction in bending capacity of up to 17%. Finally, ABAQUS models were developed for concrete cylinders and prisms to simulate the effect of inclusion of the wheat fibers.
