During the recent decades, the design and construction of underground spaces into rock salt have been particularly regarded for storing petroleum fluids, natural gas, and compressed air energy, and also for disposing nuclear and chemical wastes. The rock salt hosting such spaces will be subjected to various types of monotonic/cyclic, short-term/long-term stresses during the construction and/or ...

During the flood development in an oil field, the creep characteristic of mudstone is one of the important factors causing casing damage. In this study, based on the theory of fractional order differential and taking into account the creep damage evolution rules, a fractional nonlinear creep-damage model is proposed to reflect the instantaneous deformation in loading processes and the accelerat...

The tensile creep and creep-recovery behavior of a unidirectional Sic-fiher/Si,N,-matrix composite was investigated at 1200°C in air. A primary objective of the study was to determine how various sustained and cyclic creep loading histories would influence the creep rate, accumulated creep strain, and the amount of strain recovered upon specimen unloading. The key results obtained from the inve...

Some exploratory work on creep and inverse creep in nylon 6 monofilament, polyester multifilament yarn and wool and cotton spun yarns has been presented. It is observed that the extent of creep and inverse creep differs from material to material and depends on the initial stress. Cotton shows minimum inverse creep while nylon shows maximum inverse creep. Wool and polyester have intermediate inv...

Abstract Metamaterials have attracted wide scientific interest to break fundamental bounds on materials properties. Recently, the field has been extending coupled physical phenomena where one physics acts as driving force for another. Stimuli-responsive or 4D metamaterials demonstrated thermo-elasticity, magneto-optics piezo-electricity. Herein, a soft, ultra-compact and accurate microrobot is ...

The 60 min creep data from National Type Evaluation Procedure (NTEP) tests performed at the National Institute of Standards and Technology (NIST) on 65 load cells have been analyzed in order to compare their creep and creep recovery responses, and to compare the 60 min creep with creep over shorter time periods. To facilitate this comparison the data were fitted to a multiple-term exponential e...