Investigation on the Debonding Failure Model of Anchored Polyurea Coating under a High-Velocity Water Flow and Its Application

Abstract

The debonding failure of a polymer-based coating seriously affects the safe operation of buildings under the action of a high-velocity flood discharge flow. In order to achieve a healthy and sustainable operation of hydropower stations, the debonding failure between polyurea coating and concrete was described by the cohesive zone model, and a debonding failure model was proposed and verified. The results obtained from the model were basically consistent with the test results. Accordingly, the influence of the performance of different anchoring types, the material mechanics of polyurea-based coating and the bonding on debonding behavior were analyzed, and engineering application research was also carried out. The impact resistances of polyurea-based coating under different anchoring conditions are obtained, which provide a reference for the anti-shock and wear-resistant design of flood discharge infrastructure. The elastic modulus and Poisson’s ratio of the polyurea-based material have a significant influence on the impact resistance of polyurea-based coatings. When the elastic modulus and Poisson’s ratio of a polyurea-based material are 25 MPa and 0.45, respectively, the impact resistance is optimal. The greater the fracture energy of the bonding material, the better the impact resistance. The engineering application results show that the seepage prevention and anti-wear characteristics of flood discharge infrastructure all meet the engineering requirements.

Modeling of success factors of using PU coats in concrete construction projects

“…It is indicated that the accepted significance exists between the majority of the items because the empirical correlation leads to the acceptability of the items in the model and further justifies their presence in the formative side of the model. That is important to consider because most of the coordination observed from the analysis is greater than 0.2, which is the minimum criteria for accepting a correlation [ 26 ]. Minor deviations also exist from the accepted value of correlation, but they are still acceptable because all the constructs are contributing well to explaining the change in the model and equally justifying their involvement in the structure model.…”

“…Following is the algorithm for calculating HTMT: where r_ij is the correlation between constructs i and j, and ave (r_i,r_j) is the average of the correlations of constructs i and j with themselves. In general, the HTMT threshold value is set at 0.9 or less, suggesting that the constructs are sufficiently dissimilar from one another to have discriminant validity [ 26 , 39 ]. The cross-loading of an item on a structure may be described mathematically as follows: For construct j, the loading of item i is given by λ_ij and the residual variance of item i is given by ξ_i (Eq.…”

“…The study indicated that polyurea coatings considerably enhanced the concrete's fracture toughness, hence boosting its resistance to crack propagation. Che et al (2019) and B. Li et al (2019) examined the effect of polyurea coatings on the fire resistance of concrete in their study [ 26 , 27 ]. Benmokrane & Ali (2018) and J. Zhang et al (2019) revealed that using polyurea coatings considerably enhanced the fire resistance of the concrete, hence boosting its overall longevity.…”

A review on the applications of polyurea in the construction industry

“…Failure of this polymer coating can seriously influence the safe performance of the structures against the high‐speed flood flows. Li et al 65 studied the anchored polyurea coating failure model under high‐velocity water flow concerning its applications. They described the fracture and failure between the polyurea coating and the concrete using the cohesive zone model (CZM).…”

Preparation and Formula Analysis of Anti-Biofouling Titania–Polyurea Spray Coating with Nano/Micro-Structure

“…In the meantime, vacuumed mixer obtained by the spraying equipment could contribute to realize suitable mixing and remove the waste product and carbon dioxide shortly [29]. Besides, different drying methods, air-drying and oven-drying, were also tried under Group 3, would have an impact on the curing time of TiO 2 -SPUA coating surface in the mould [30]. As for foam inside such a coating, both technology-based methods (e.g., vacuum degree inside the spraying equipment) and chemical-based prescription (e.g., defoamer, such as PDMS and IPA) have been conducted to address this issue [10].…”