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We present a new method for synthesizing cold‐resistant laminated anti‐fire glass using a K2O·nSiO2‐based ultrathin flexible membrane, which is prepared by vacuum surface treatment method with ball‐milled core–shell SiO2 emulsion (55 wt%). We systemically characterize the mechanical, optical, rheological, cold‐resistant, fire‐resistant, and weather‐resistant performances of this glass. The formation mechanism of K2O·nSiO2‐based ultrathin membrane is studied in detail using multispeckle diffusing–wave spectroscopy and scanning electron microscopy. Then, the tensile strength, plasticity, and rheological behavior of the materials with different moduli are characterized. Combined with thermal gravity analysis, we characterize the compositions of K2O·nSiO2‐based materials with different moduli. For the K2O·nSiO2‐based ultrathin flexible membrane, the appearance of air‐conducting microchannels is designed, resembling the Wu Zhu coin morphology (a square hole circular coin in ancient China) or honeycomb wall morphology. These structures endow the visible region of the anti‐fire glass with a reduced presence of microbubbles. As a type of building safety glass, the spongelike microporous insulation layer can increase the heat‐insulating time in the event of a fire. Furthermore, the weather‐resistant performance of this glass is demonstrated to be more than 3000 h through an ultraviolet test. This work also provides a new routine for synthesizing high‐quality anti‐fire glass with different shapes, including curved surfaces. [ABSTRACT FROM AUTHOR]

• Completed graded upper stress limit interval fatigue (GUIF) tests and graded lower stress limit interval fatigue (GLIF) tests, comparing the effects of different time intervals and stress amplitudes on the fatigue failure characteristics of mudstone. • The fatigue life of mudstone shows an increasing trend with increasing time intervals. • The study found that the residual strain cycles before and after the time intervals exhibited opposite patterns in the GUIF tests compared to the GLIF tests. • In discontinuous graded fatigue tests, the impact of the fatigue stage on the damage to mudstone was smaller than the impact of the interval stage. During the operation of an underground salt cavern gas storage, Fatigue failure occurs in the surrounding rock of gas storage reservoirs under non-continuous gas injection and extraction loading. Due to the special layered salt rock structure in China, the mudstone interlayer is the weak part of the gas storage. It is necessary to study the effect of stress magnitude and interval time on the fatigue mechanical properties of mudstone. Graded upper stress limit interval fatigue (GUIF) test and graded lower stress limit interval fatigue (GLIF) test were carried out on mudstone respectively. And different interval times were set to investigate the effect of interval time on the mechanical properties of mudstone. With the increase in the interval time, the fatigue life and peak strain of the mudstone increased. Under the same interval time, the lower-limit interval test result showed a significantly higher fatigue life than the upper-limit interval test result. The stress–strain curve exhibited three stages: scattered–dense–scattered. During the unloading phase, the modulus of elasticity increased with increasing stress levels, indicating that the internal structure of the mudstone is extremely sensitive to the stress. In the (GUIF) test, the average residual strain increased with the increase in the interval time, and the residual strain during the cycle after the time interval under different grades was lower than the residual strain before the time interval; the results of the (GLIF) test showed the opposite trend. In the (GUIF) test, the average creep strain increased with increasing interval time under the same stress level, and the average creep strain was greater than the average residual strain, and the creep stage had a greater effect on mudstone damage than the fatigue stage. The post-fatigue creep strain was significantly greater than the pre-fatigue creep strain. The research results can be useful in ensuring the stable operation of gas storage in salt caverns. [ABSTRACT FROM AUTHOR]

Most soft interlayers tend to be key factors affecting rock slope stability due to their low strengths. A series of ring shear tests is conducted on reconstituted overconsolidated soft interlayers to investigate the influences of remolded water content and normal stress on shear behavior under drained conditions. The soft interlayer raw samples taken from a potential landslide site in China are first remolded into overconsolidated samples with different water contents but the same dry density and further drained under different normal stresses. The peak strength, residual strength, corresponding shear displacement of the soft interlayers and the loss rate of water content are positively correlated with water content and normal stress. Transformation of strain softening to strain hardening occurs for samples under higher normal stresses. Variations in water contents have notable effects on the shear strengths. Meanwhile, displacements, fragmentations and orientations of samples differ, showing strain softening and hardening behaviors of soft interlayers. • Stress-strain characteristics of soft interlayers are systematically investigated. • Ring shear test is utilized successfully for shear behavior studying. • Variation in compaction moisture content has an obvious effect on shear strength. • Shear behaviors are closely related to the microstructure of soft interlayers. [ABSTRACT FROM AUTHOR]

• Sand impact loading was the primary factor causing the laminated glass damage. • Crack initiation was driven by the reflected tensile and Rayleigh surface waves. • Size of sandstone and impact angle were sensitive to the impact scratch velocity. China has built high-speed railways in desert areas. When high-speed trains run in wind-sand flows, wind pressure and sand impact increase the fracture probability of side-window laminated glass. This paper aims to explore the dynamic response and impact resistance performance of laminated glass in high-speed trains subjected to windborne sand particles loading using full-scale experimental tests. Dynamic pressure tests were carried out using an air cannon on the laminated glass to evaluate the glass response under wind dynamic pressure loading. Sandstone impact tests were conducted to study the laminated glass dynamic behavior during particle impact loading. The study results demonstrate that sand impact loading was the primary factor causing the laminated glass damage. The mixed-mode crack initiation and propagation were driven by the reflected tensile waves and Rayleigh surface waves under sandstone impacts. In addition, a statistical analysis of the scratch velocity of the laminated glass suggested that the size of sandstone and impact angle were sensitive to the scratch velocity in the sand particles impacts. This research provides practical help for designing crack-resistant laminated glass structures for high-speed trains. [ABSTRACT FROM AUTHOR]

• One ultra-thin antiskid surface layer (UTASS) was designed and evaluated. • A cold-mixed epoxy resin binder was selected as the binder material of UTASS. • The UTASS can improve the skid resistance of epoxy asphalt concrete (EAC) pavement. • The developed EAC-UTASS composite structure performed good performances overall. To improve the skid resistance of epoxy asphalt-based concrete (EAC) pavement, a cold-mixed ultra-thin antiskid surface layer (UTASS) was developed and incorporated into the EAC pavement in this study. The performances of four types of epoxy resin-based binders were assessed. The best binder type was selected and UTASS preparation procedures were determined. Subsequently, the skid resistance, high-temperature rutting resistance, low temperature cracking resistance, and interlayer bonding properties of the EAC-UTASS composite structure (with the UTASS on the top of the EAC) were evaluated using a series of tests, and the performances of EAC-UTASS were compared with several other composite structures that are commonly used in the steel bridge deck pavement (SBDP) in China. The results showed that the texture depth of EAC-UTASS is almost 10 times of that of the pavement composite structures with an EAC surfacing structure. In addition, EAC-UTASS has excellent high-temperature rutting resistance, low-temperature cracking resistance and interlayer bonding stability. Finally, a stripping resistance test was utilized to evaluate the UTASS based on a third-scale Model Mobile Loading Simulator (MMLS3). The service life of UTASS was determined based on the anti-stripping coefficient threshold value of 80%. Based on the results in this study, the use of the UTASS was found to be a feasible strategy for enhancing the skid resistance of EAC pavement. [ABSTRACT FROM AUTHOR]