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The logical coherence macro–micro experiments about the anti‐swelling performance of polyetheramine‐230 (PEA‐230) on expansive natural soil are presented in this paper. Further, the expansion of the soil in the solution and water system is considered. Great significance in treating the expansive soil broadens the applied range of polyetheramine‐230. The mechanism is assessed by X‐ray diffraction (XRD) in the state of wet and dry montmorillonite (Mt), XRD of dry clay extracts from the soil, zeta potential measurement, thermogravimetric analysis, and scanning electron microscopy. The results prove the significant effect of controlling the expansion of expansive soil. PEA‐230 strongly adsorbs on the surface of soil particles and intercalates into the layer structure. Further, the PEA‐230/soil hybrids can be judged as usable engineering soil with low expansion characteristics. Additionally, the concentration of PEA‐230 controls the treatment effect, and 1 wt% PEA‐230 is a proper concentration to treat the expansive soil. In particular, PEA‐230 has excellent characteristics such as small molecular weight, good water solubility, and good stability. Thus PEA‐230 can be regarded as a great agent to treat in‐situ expansive soil.

The dynamic vibrations of airport runways induced by moving aircraft loads are semi-analytically studied in this paper. The airport runway consists of an infinite Kirchhoff plate, an elastic base course, and an unsaturated poroelastic half-space. The aircraft loads are modeled according to the mechanical properties of the main landing gear of the A380 civil airliner. The governing equations of the whole system are solved in the wavenumber domain using the double Fourier transform. Then the results in the spatial domain are obtained by applying the inverse double Fourier transform. Various parameters including the observation location, soil saturation, load speed, load frequency, and pavement rigidity on the vibration characters of the whole system are investigated. It is found that all these effects are crucial, and the increase of soil saturation leads to a larger maximum vertical displacement and lower critical speed.