Bond Properties of Carbon Fiber Reinforced Polymer and Corrosion-Cracked Reinforced Concrete Interface: Experimental Test and Nonlinear Degenerate Interface Law

Existing experimental research on bond properties of the interface between Carbon Fiber Reinforced Polymer (CFRP) and damaged concrete is limited, although CFRP strengthening technology has been widely used for corroded reinforced concrete structures. This work investigated the bond behavior of CFRP to the corrosion-cracked concrete interface, in which three factors were considered for experimentation, including corrosion degree, concrete strength and concrete cover thickness. The tests were conducted by developing a self-balancing double shear lap test device. In addition, a corrosion scene was provided simultaneously to simulate the external corrosion environment. The results showed that three peeling modes of CFRP sheets were observed with respect to corrosion degrees of the steel bars. The effects of the three factors on the stripping bearing capacity and effective bond length of CFRP sheets were discussed by systematic parametric analysis. Finally, a nonlinear degenerate law of CFRP-to-concrete interface considering the corrosion degree was improved and verified in this study.

An oscillation theorem for the nonlinear degenerate elliptic equation in the Heisenberg group

The aim of this paper is to study the oscillation of solutions of the nonlinear degenerate elliptic equation in the Heisenberg group $H^{n}$ H n . We first derive a critical inequality in $H^{n}$ H n . Based on it, we establish a Picone-type differential inequality and a Sturm-type comparison principle. Then we obtain an oscillation theorem. Our result generalizes the related conclusions for the nonlinear elliptic equations in $R^{n}$ R n .

Radon Measure-valued Solutions for Nonlinear Strongly Degenerate Parabolic Equations with Measure Data

In this paper, we prove the existence of Radon measure-valued solutions for nonlinear degenerate parabolic equations with nonnegative bounded Radon measure data. Moreover, we show the uniqueness of the measure-valued solutions when the Radon measure as a forcing term is diffuse with respect to the parabolic capacity and the Radon measure as a initial value is diffuse with respect to the Newtonian capacity. We also deduce that the concentrated part of the solution with respect to the Newtonian capacity depends on time.