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This paper presents results from a numerical study performed to examine thermal effects on cylindrical cavity expansion response. In order to highlight thermomechanical behaviour of soils, limit pressure, stresses and strains around the cavity are presented. A finite difference analysis, which accounted for large strains and thermal effects, was carried out using Flac V 7.00 (Itasca Consulting Group). The model assumed the soil as a homogeneous elastic perfectly plastic material with a Mohr–Coulomb yield criterion. The results of the numerical simulation are compared with an analytical one and showed a good agreement. Numerical results suggest a significant influence of the soil temperature on the limit pressure, stresses and displacements. The limit pressure of the soil around the cavity increases with heating by 18% at a temperature variation of 40 °C and decreases by 14% when cooling at a temperature variation of − 40 °C. Results are applicable in the interpretation of pressuremeter tests, waste disposal problem and geothermal piles which represent an efficient and reliable solution using the geothermal source for heating and cooling buildings.

Purpose: This paper investigates the vibration control of a stay cable using passive superelastic shape memory alloys (SMA) damper. Methods: The control of one vibration mode of a stay cable by optimized SMA damper parameters attached transversely to the cable is considered. A parametric study on two parameters, specifically, cross-sectional area and length of the damper, is conducted numerically. Results: Results show that optimized SMA damper can achieve significant damping improvement. The considered damper exhibits superior control performance over Magnetorheological damper for the target mode. However, designing the damper for a specific mode leads to vibrating other modes, revealing that optimized SMA damper is unable to provide sufficient supplemental modal damping to the stay cable. To achieve coupled multi-modal control an optimization criterion was developed through an analytical and numerical approaches. Conclusion: The optimization results indicate that the SMA damper is potential to reach a significant control performance, mitigating simultaneously the vibration of three coupled modes which looks promising for practical applications.

This paper aims at presenting an analytical solution to the problem of an expanded cylindrical cavity submitted to temperature variation. In this analytical model, the elastoplastic behavior is governed by Mohr–Coulomb’s strength criterion. The problem is formulated by incorporating temperature variation into the theoretical framework of cavity expansion. The results led to the development of a relationship between the limit pressure and the temperature variation which suggest a significant influence of the soil temperature on the limit pressure. The influence of temperature variations on the mechanical response of saturated soils is highlighted through several numerical applications, confirming the effectiveness of the proposed formulation. Such a constitutive model, which predicts the thermoelastoplastic soil behavior around the cylindrical cavity is applicable in many geotechnical engineering problems related to soil mechanics; such as the interpretation of pressuremeter tests in saturated soils, geothermal piles and nuclear waste disposal problems.