1. Carl MontgomeryJr. Faculty Mentor: Dr. Sergio Mendez
Chemical Engineering Department
California State University, Long Beach
Fabrication and Testing of Green Composite Materials for Concrete
Reinforcement
It is becoming popular to reinforce concrete structures with carbon fiber material that is
versatile and extremely strong. However, there are concerns that this carbon fiber material can
lead to adverse environmental toxicity as the materials decompose with age. We aim to create a
sustainable green alternative for the application of concrete reinforcement.
In this research project, we used both the hand lay-up and vacuum resin infusion
chemical processes to fabricate composites made from woven hemp or flax fabrics, along with
purely synthetic resin as well as a “bio-resin”. Hemp and carbon fiber fabrics were chosen

2. because of their lightweight and exceptional mechanical properties. Briefly, for the chemical
procedure we employed to prepare the composite panels, first swaths of fabric were measured,
cut and set on a hard surface that was the mold. In the hand lay-up process, the resin and
hardener were poured over the fabric and a plastic trowel was used to evenly distribute and
remove excess resin and unwanted air pockets. After the resin was infused in the fabric, another
fresh piece of cut fabric was laid on top of the wet one, and the aforementioned steps were
repeated until the desired blade thickness was achieved. The wet panels were then sealed in
plastic sheeting and a vacuum was applied at room temperature. The vacuum served to remove
unwanted pockets of gas within the plies of fabric, and to compress the panel. After curing
overnight under vacuum, the panels were then ready to be trimmed to the specified dimensions.
For the vacuum-infusion process, all the fabric swaths were simultaneously infused with the
resin, and then left under vacuum overnight for room-temperature curing. The hardened panels
were consequently adhered to concrete beams, and we measured the force-versus-displacement
curves. Our preliminary results indicate that the green composite panels do impart additional
mechanical strength to concrete beams.
The introduction of green composites to the concrete will be beneficial to the
environment because for one, you will not have to worry about it being environmentally toxic
and it is cost much less than carbon-fiber materials. Although carbon-fiber has the advantage of
being stronger than green composites, the disadvantage is potential toxic exposure to humans. In
the future, we will further refine the chemical process to fabricate the concrete reinforced
structures with green composites, and hope to apply green composite to concrete structures.