This paper presents the results of an experimental investigation of the effect of wetting-drying cycles on the surface cracking and swell-shrink behavior of modified expansive soils. An image processing technique was employed to understand this effect by quantifying the surface crack area density, crack number, crack length, mean crack width, and absolute shrinkage. Parameters such as height, the relative rate of expansion, and linear shrinkage were used to characterize the effect of wetting-drying cycles on the swell-shrink behavior of the specimens subjected to various overburden pressures. The results showed that the increase in the number of wetting/drying cycles accelerated the crack growth and led to the increased crack number, total crack length, and surface crack area density. Moreover, as the number of wetting/drying cycles increased, the absolute shrinkage to be on the rise, and the mean crack width exhibited fluctuation characteristics. Furthermore, the moisture content was inversely related to the crack extent. For the specimens subjected to various overburden pressures, the height and the moisture content showed a good linear relationship. With the increase in wetting/drying cycles, the relative rate of expansion of the specimen decreased. Additionally, a larger overburden pressure resulted in a lower relative rate of expansion; however, as the number of wetting/drying cycles increased, the relative rate of linear shrinkage increased and then decreased.
Life Prediction Method Under Creep-Fatigue Loading for Gas Turbine Combustion Transition Piece of Ni-Based Superalloy N263
