Hydraulic Abrasion-Resistant Elastic Epoxy Resin Materials

Liqun Xu,Yanhui Liu,Kai Zhang

doi:10.1155/2019/9358139

Abstract

The abrasion of hydraulic concrete structures caused by the washing action of flowing water is a common problem and cannot be solved by simply increasing the strength of the concrete. To ensure safe operation, increase in service life and reduction of maintenance costs of hydraulic concrete structures and the development of abrasion-resistant materials are required. In this work, polyurethane-modified epoxy resin was synthesized using the interpenetrating network technology (IPN). After many mixing experiments, the ratio of polyether amine to alicyclic amine in Component B was determined to be 29 : 14 and the ratio of Component A to Component B was 7 : 3. With these ratios, elastic epoxy achieved a tensile strength of more than 15 MPa and an elongation rate of more than 20%, thus balancing strength and toughness. The effects of the curing conditions, the ratio of Component A to Component B, and diluents and fillers on tensile strength and elongation of the elastic epoxy resin were analyzed. The results of the analysis indicated that the curing duration should be over 7 days, the optimal proportion of Component A to Component B should be 7 : 3, and the diluent of the elastic epoxy material should be the bifunctional butanedioldiglycidyl ether (622). The reliability of this material was determined by pull-out testing, adhesion, and tensile strength testing. The underwater steel ball test and ring test were adopted as the abrasion-resistance tests for the elastic epoxy resin material. The results showed that the abrasion-resistance performance of elastic epoxy coating improved hundreds of times over that of common concrete. Although the wearing strength was reduced with pressure, the elastic epoxy coating still retained excellent abrasion-resistance performance. At last, future application prospects of elastic epoxy improvement products are introduced and need further reach.

Highlights

The elastic epoxy material was synthesized by applying the method of polyurethane-modified bisphenol A epoxy resin, which has an elongation rate of over 20%, and a tensile strength close to polyurea. is synthesis is a breakthrough over traditional epoxy toughening
Based on the elastic epoxy material, after several adjustments of color, thixotropy, and aggregate gradation, an elastic epoxy coating material that can be directly used in the form of spraying or coating has been developed, and it can be used as a permanent protection layer attached to the protected surface of concrete in order to resist abrasion. e detailed conclusions are as follows: (1) After many mixing experiments, the ratio of Component B, composed of polyether amine and the alicyclic amine compound in the proportion of 29 : 14, and Component A at the ratio A : B 7 : 3 was determined to be optimal
In the ratio mentioned above, polyurethane-modified epoxy resin synthesized by the interpenetrating network technology (IPN) technology achieved a tensile strength greater than 15 MPa and the elongation rate greater than 20% so that it achieved the balance of strength and toughness

Summary

Introduction

Outlet structures, such as overflow dams and spillway tunnels, are commonly subjected to abrasion, and damage to concrete caused by cavitation erosion and grinding is quite common, when high-velocity water carries sediments and rocks. E abrasion and cavitation erosion may affect safety, so repair or reinforcement of these outlet structures is necessary [1]. Hydropower stations, such as Baihetan (China), Jinping (China), and Laxiwa (China), have high water heads (over 200 m) and high flow velocities (up to 40–50 m/s), while the discharge volumetric flow rate of a single spillway tunnel can reach 3000 m3/s to 4200 m3/s. High flow velocities with solid particles have high kinetic energy, which leads to increased erosion damage; it is necessary to improve the antiabrasion performance of the material of the outlet structures

Methods

Findings

Discussion

Conclusion