Experimental and numerical study on improving mechanical properties of new polyurethane-emery thin polymer overlay (TPO) structure using three-point bending test

Abstract

The thin polymer overlay (TPO) is a new type of road surface treatment layer for high traffic pressure and high road performance requirements. Therefore, it is not only widely used on highways but also has more and more applications in the field of bridge deck pavement. In this work, a new type of TPO—the polyurethane-emery TPO composite material was proposed, and a reasonable material mixing ratio is determined. In addition, the flexural and compressive behaviors of the polyurethane-emery TPO reinforced with the steel fiber and cement materials are investigated, and a comparison is made for the development of a numerical model to simulate the behavior of the reinforced-new-TPO using the Finite Element (FE). The experimental tests include three-point bending and compressive tests to evaluate the ultimate capacity of the new-TPO material in flexural and compression and its modulus of elasticity. Moreover, the flexural and compression performance of polyurethane-emery TPO containing different reinforcement configurations was evaluated in three-point bending and compression tests, and the reinforcing effects of different steel fibers and cement contents were investigated. The use of steel fiber and cement-reinforced thin polymer overlay in reinforced bridge surface treatment construction was found to be able to significantly offer several advantages, such as excellent corrosion resistance, and flexural and compression strength. Through experimentation, it can be seen that the new type of polyurethane-emery TPO proposed in this paper can completely replace the existing TPO, however, the effect of the dosage of steel fiber and cement needs to be considered during the design. Meanwhile, a three-dimensional nonlinear finite element model was established by using ABAQUS, which incorporated the second development model of steel fiber based on python and CDP models and can be used to predict the flexural and compression behaviors. The numerical model was experimentally validated by using the three-point bending and compression test results and was used for parametric studies. The parameters investigated in this study were steel fiber content, fiber length, and polyurethane-cement ratio of the polyurethane-emery TPO reinforcement. The proposed new polyurethane-emery TPO system was revealed to be promising for the development of the bridge surface treatment reinforcement formwork and can be used in superstructure construction for the extension of the bridge service life. The numerical and the experimental results were generally in good agreement.