Fatigue Analysis for Void Repair of Cement Concrete Pavement with Under Slab by Polymer Grouting

Abstract

After the appearing of voids beneath cement concrete slabs, the pavement loses a continuous and uniform lower support structure, and the stress state of the road panel is extremely unfavorable. The polymer grouting repair is timesaving, efficient and pollution-free. In order to verify the performance improvement and fatigue damage evolution of cement concrete pavement before and after grouting repair, a material damage constitutive model was established. The UMAT subprogram was introduced into the finite element software ABAQUS to analyze the structure under the action of moving cyclic loading, stress response and fatigue damage evolution process before and after regional grouting repair. The results show that the Mises stress and vertical displacement of the grouting repairing slab are very close to the normal state, which indicates that the grouting repair has a prominent influence on the bottom void of the slab. With the rise of loading time, the fatigue damage of the pavement structure is increasing, but the trend is gradually reduced, and the number of load times and the degree of fatigue damage are nonlinear. From the long-term cyclic loading and comprehensive analysis of the construction period, the polymer grouting repair is better than cementitious grout.

Research on Mechanical Response of Polymer Grouting Repair for Longitudinal Cracks in Reconstructed and Expanded Expressway Pavement

“…e polymer grouting material used in this paper was mainly composed of polyether polyol, polyisocyanate, foaming agent, catalyst, foam stabilizer, and various other auxiliary agents. e chemical polymerization reactions that take place mainly include foaming reactions and gelling reactions [11][12][13]. e foaming reaction refers to the chemical reaction between polyisocyanate groups and hydroxyl groups, mainly generating carbon dioxide and urea, and generating a large amount of heat.…”

Surface Free Energy Theory for Evaluating Moisture Damage in Expandable Polyurethane Grouting Materials

“…The produced PU matrices are also characterized by fast setting and high strength, by virtue of which, they have been widely adopted as raw materials in the rehabilitation of roadbeds, pipelines, and the sealing of dam leakage field with the grouting method. [1][2][3][4][5] Figure 1 shows the application of polymer grouting technology in the roadbed rehabilitation project. [6] As shown in Figure 1, this grouting method refers to the pressurized injection of polyurethane (PU) matrices directly into the semirigid base material cavities.…”

An Experimental Study on the Reinforcement of Silt with Permeable Polyurethane by Penetration Grouting

“…Due to characteristics such as low viscosity, low density, short gelation time, and high strength and strong chemical stability after solidification [23], polyurethane materials have been widely used in the grouting repair of highways [24,25], dams [26], tunnels [27], and other infrastructures. However, the main material used is polyurethane, which is able to quickly react and expand.…”