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CRTS III (China Railway Track System III) slab ballastless track structure is one of the high-speed railway ballastless track structures which has Chinese independent intellectual property rights. The mechanical performance of CRTS III slab ballastless track structure under temperature load has not been clear yet. Therefore, through temperature field model and temperature load values selected by statistics analysis based on long-term meteorological data, the mechanical performance of ballastless track structure is studied under two typical working conditions with different safety probability. It is found that the daily extreme values of monthly axial uniform temperature and the daily maximum temperature gradient obey certain statistical laws. In addition, the maximum tensile stress of the self-compacting concrete layer is located in the middle and edge of the slab bottom and the side of the slab. The maximum tensile stress of the base plate is located at the edge of the surface of the layer and the inner edge of the limiting groove. The interface normal tensile stress is located at the end and corner of the interface. Furthermore, maximum stress increases with the increase of safety probability.

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Microbial‐induced carbonate crystallization is a natural biological process in which microbes produce inorganic materials as part of their basic metabolic activities. Herein, the influence of the bacterial somatic solution and secretion solution on the crystal growth behavior of strontium carbonate (SrCO3) is studied. The mineralization mechanism of carbonate mineralizing bacteria on simulated radionuclides (Sr2+) is also demonstrated. The results reveal that the morphology of SrCO3 crystal formed by involvement of microbes is greatly different with chemical method, which means that microbes play a critical role during the SrCO3 crystallization process. Briefly, bacterial somatic provides nucleation sites for SrCO3 during both the nucleation and growth processes. In addition, bacterial secretions play a vital role in regulating the morphology of mineralized products. This work unveils the mineralization process of strontium nuclides, providing reference for the control of crystal morphologies and structural properties of the SrCO3.

In this paper, nano-montmorillonite (nano-MMT) was introduced into the microbial mineralization system of strontium carbonate (SrCO3). By changing the nano-MMT concentration and the mineralization time, the mechanism of mineralization was studied. SrCO3 superstructures with complex forms were acquired in the presence of nano-MMT as a crystal growth regulator. At low concentrations of nano-MMT, a cross-shaped SrCO3 superstructure was obtained. As the concentration increased, flower-like SrCO3 crystals formed via the dissolution and recrystallization processes. An emerging self-assembly process and crystal polymerization mechanism have been proposed by forming complex flower-like SrCO3 superstructures in high concentrations of nano-MMT. The above research indicated that unique bionic synthesis strategies in microbial systems could not only provide a useful route for the production of inorganic or inorganic/organic composites with a novel morphology and unique structure but also provide new ideas for the treatment of radionuclides.