Experimental Study on Tensile Mechanical Properties and Reinforcement Ratio of Steel–Plastic Compound Geogrid-Reinforced Belt

The steel–plastic compound geogrid has been widely used as a new reinforcement material in geotechnical engineering and other fields. Therefore, it is essential to fully understand the mechanical properties of steel–plastic compound geogrid-reinforced belts to utilize steel–plastic compound geogrids efficiently. In this study, tensile mechanical tests of steel wire, polyethylene geogrid belt, and steel–plastic compound geogrid-reinforced belt were conducted with respect to the tensile mechanical properties of steel–plastic compound geogrid-reinforced belts. In addition, the minimum reinforcement and optimal reinforcement ratios of steel–plastic compound geogrid-reinforced belts were summarized. The results showed that the steel–plastic compound geogrid-reinforced belts possessed an incongruent force of the internal steel wire during the tensile process. The tensile stress–strain curve of the steel–plastic compound geogrid-reinforced belt can be divided into the composite adjustment, steel wire breaking, and residual deformation stages. The tensile strength of the steel–plastic compound geogrid-reinforced belt is proportional to the diameter and number of steel wires in the reinforced belt. The minimum and optimum reinforcement ratios of steel wire in the steel–plastic compound geogrid-reinforced belt were 0.63% and 11.92%, respectively.

Effect of Aminosilane Concentrations on the Properties of Poly(Lactic Acid)/Kenaf-Derived Cellulose Composites

To reinforce the use of kenaf-derived cellulose as a compatible plastic filler, the cellulose (C) was thermally grafted with various concentrations (5, 8, and 11 wt.%) of hydrolysed 3-aminopropyltriethoxysilane (APS). The silane-grafted cellulose (SGC) were named as SGC5, SGC8 and SGC11. C (30 wt.%) and all of the SGC were respectively melt-compounded into poly(lactic acid) (PLA) before being hot-pressed into ∼0.3 mm sheets, which is the approximate thickness of clamshell packaging. The intermolecular interaction between SGC and PLA, which was absent with C, was confirmed via Fourier Transform Infrared Spectroscopy (FTIR). PLA filled with SGC5 or SGC8 showed significant improvement in thermal, tensile, physical, and barrier properties compared with the PLA/C composite. In contrast, adverse effects were observed with the PLA/SGC11 composite. 8 wt.% of APS was concluded as the critical concentration to be thermally-grafted onto the kenaf-derived cellulose as PLA/SGC8 composite showed optimum reinforcement in tensile strength (52 MPa), crystallizability (16% crystallinity), water resistance (5.3%) and dimensional stability (3.3%), and significantly shifted oxygen barrier from medium-low range to medium range (3.2 ×10−17 m3 m/m2 s Pa). Overall, the variation in the properties of these biocomposites may extend PLA's range in food packaging applications.

A computational and experimental study for the optimum reinforcement layout design of an RC frame

Purpose Compared with conventional design methods, strut-and-tie modeling is a more suitable and even a superior method for the reinforcement layout design of structural members with uncommon geometrical shapes and/or regions essentially subject to shear effects. Because the determination of the optimum strut-and-tie model for each of the members is an important task, the implementation of a topology optimization method could be useful before the detailing stage. Design/methodology/approach Optimum reinforcement layout of a concrete frame was designed by an integrated approach, which consists of the topology optimization and strut-and-tie modeling methods. Subsequently, an experimental comparison of the new model with the conventional model was performed based on their structural behaviors. Findings Depending on the experimental results, it was concluded that the new integrated design method presents more successful results than does the conventional method for the design of reinforced concrete (RC) members. Originality/value The preference of the new method will facilitate the design process by eliminating the experience required of design engineers.