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Determination of the mechanical strength of stones after freeze–thaw action is important for evaluating the durability of natural building stones used in cold regions. In this research, we proposed a novel physico-mechanical parameter (PMP) for estimating the mechanical strength of travertines after a freeze–thaw test, which is based on initial mechanical strength, effective porosity, and mean pore size of the stones. For this purpose, 12 samples of travertines were selected and their initial mechanical strengths (uniaxial compressive, Brazilian tensile and point load strengths), effective porosity, and mean pore size were determined. Then a freeze–thaw test was conducted up to 60 cycles on samples, and their mechanical strengths were measured. The results showed that PMP is in good accuracy for estimating the mechanical strengths of stones after a freeze–thaw test, and thus making a rapid durability assessment. As a result, the PMP avoids performing a freeze–thaw test, which is laborious and time-consuming.

This paper presents the influence of freeze–thaw cycles on physical and mechanical properties of Alvand granitoids hard rocks, in the west of Iran. For this purpose, three different types of Alvand granitoid rocks were selected and studied. For assessment of freeze–thaw weathering effects, a long-term freeze–thaw test was carried out for 300 cycles. P-wave velocity, porosity, water absorption, dry density, uniaxial compressive strength, and tensile strength of specimens were determined prior to doing the test and after every 50 cycles. The results of this study show that, by increases in the number of freeze–thaw cycles, uniaxial compressive strength, tensile strength, dry density, and P-wave velocity decreases, whereas the water absorption and porosity increases. P-wave velocity and tensile strength were also suggested as the best indicators to assess the effects of freeze–thaw cycles on the physical and mechanical properties of the studied granites.

The effects of wet–dry, freeze–thaw, and heat–cool cycles on the physical and mechanical properties of Upper Red Formation sandstones located southwest of Qom, central Iran, were determined. Five different types of sandstones were selected, and freeze–thaw, wet–dry, and heat–cool cyclic tests were performed. The freeze–thaw test was carried out for 30 cycles, and the P-wave velocities, porosities, and uniaxial compressive strengths of the specimens were determined after every five cycles. Heat–cool and wet–dry cycles were repeated for 40 cycles. Based on the strength deterioration ratio, it was found that freeze–thaw cycles degrade the physical and mechanical properties of sandstones more strongly than heat–cool and wet–dry cycles do. The results also show that the presence of zeolite cement has a significantly effect on sandstone resistance to freeze–thaw cycles. Further, it was found that sandstone strength as well as petrographic properties such as grain size and grain contacts do not have the expected effect on sample deterioration during freeze–thaw cycles. Finally, it was concluded that pore size plays an important role in sandstone resistance to freeze–thaw cycles.

Uniaxial compressive strength (UCS), which is one of the most important engineering properties of natural building blocks, exhibits a decrease at various rates under the effect of freeze–thaw (FT) cycles. In this study, practical estimation of UCS loss of 21 groups of carbonate building stones exposed to 4, 7, 10, 14, 20, 28, 35, 56, 70 and 84 FT cycles is aimed by proposed estimation models. In all models, the Leeb hardness (HLD), which is practically determined by a dynamic surface hardness test method, was used as major input parameter. Other basic stone properties and number of FT cycles were also used as additional input parameters in developed models. The test results indicated that HLD and UCS values decreased up to 13 and 40%, respectively, at the end of 84 FT cycles. Proposed equations are reliable and beneficial in estimation of deteriorated UCS values of carbonate building stones in practical engineering applications and scientific studies.

To exploretheeffects of physical, mechanical, anti-deterioration properties of graphene oxide (GO) on cement-based cementitious materials, GO sheet dispersions areprepared by the improved Hummers method and ultrasonic dispersion method. The influence of theGO content on the compressive and flexural strengths of cement paste is investigated, and the penetration process of chloride ions in graphene oxide concrete is discussed by the electric accelerated erosion method. Combined with the rapid freeze-thaw test, the deterioration of graphene oxide concrete ismethodically analyzed. Theobtained results reveal that an appropriate amount of GO improves both the compressive and flexural strengths of cement pastev. In the chloride environment, the chloride diffusion coefficient of 0.03% GO concrete is 18.75% less than that of ordinary concrete.Under the action of freeze-thaw cycles, with the increase of salt freezing times, the deterioration mode of GO concrete is a combination of mortar shedding, micro-crack expansion, denudation, and block shedding; The stress-strain curve of the specimen tends to be flat with the growth of salt freezing times. The peak stress gradually lessens, the peak strain gradually grows, and the elastic modulus remarkably reduces. Compared with ordinary cement paste, theGO is capable of promoting the growth of cement paste hydration crystals, changing the size and shape of crystals, and realizingthe regulation of cement paste microstructure. Incorporating an appropriate amount of theGO could promote the cement hydration process and enhance the chemical water-binding amount in the cement paste. The optimal GO content is reported to be 0.03% of the cement mass.

The integration of palm fiber with Microbially Induced Calcite Precipitation (MICP) technology offers a sustainable and bio-based approach to enhance the mechanical performance and durability of sandy soils, particularly under freeze-thaw conditions. In this study, a systematic experimental investigation examines the effects of varying palm fiber contents (0%−0.30%) on the bearing capacity, crust thickness, calcium carbonate deposition, and freeze-thaw resistance of MICP-treated sand. Results indicate that mechanical performance improves with increasing fiber content, peaking at 0.15%, beyond which the benefits diminish due to fiber agglomeration. At the optimal dosage, the bearing capacity increases by 24%, crust thickness by 70.5%, and calcium carbonate content reaches 16.8% compared to fiber-free MICP samples. Freeze-thaw tests demonstrate higher mass and strength retention, indicating improved durability. Microstructural analyses using SEM, XRD, EDS, and FTIR reveal enhanced microbial attachment and uniform CaCO₃ precipitation along fiber-sand interfaces, which strengthens matrix cohesion. These findings uncover a hybrid bio-mechanical reinforcement mechanism and highlight the trade-offs between fiber dosage and pore connectivity. This study provides novel insights into fiber-assisted biomineralization and offers a viable pathway for environmentally friendly soil reinforcement. Furthermore, potential directions such as predictive modeling, biodegradability assessments, and field-scale application are proposed to support long-term geotechnical and ecological engineering deployment.

This paper aims to investigate the effects of zeolite and palm fiber on the strength and durability of cement soil. Based on the findings of previous research, optimal proportions of zeolite, palm fiber, and cement, as well as the appropriate curing age, were determined. Subsequently, unconfined compressive strength tests, dry-wet cycle tests, and freeze-thaw tests were conducted, utilizing NaCl and Na 2 SO 4 solutions over the specified curing period. The strength and durability characteristics of the samples were evaluated by assessing mass and strength loss, taking into account the combined effects of NaCl and Na 2 SO 4 solution erosion. The test data also provide a fitting relationship between strength and the number of cycles under the influence of different solutions, thereby offering a basis for theoretical predictions without the need for additional experiments. Finally, the microscopic mechanisms were analyzed using scanning electron microscopy (SEM). The results indicate that the cement soil composite of zeolite and palm fiber, when combined in optimal proportions, exhibits the best durability and minimal loss of strength and mass, irrespective of whether exposed to clean water or salt erosion, as well as during dry-wet or freeze-thaw cycles.

Damages to natural building stones induced by the action of frost are considered to be of great importance. Commonly, the frost resistance of building stones is checked by standardised freeze–thaw tests before using. Corresponding tests normally involve 30–50 freeze–thaw action cycles. In order to verify the significance of such measurements, we performed long-term tests on four selected rocks over 1,400 freeze–thaw action cycles. Additionally, numerous petrophysical parameters were analysed to compare the behaviour of rocks in the weathering tests according to the current explanatory models of stress formation by growing ice crystals in the pore space. The long-term tests yield more information about the real frost sensibility of the rocks. A clear deterioration cannot be determined in most cases until 50 weathering cycles have been completed. In the freeze–thaw tests, the samples are also stressed by changing temperature and moisture, indicating that different decay mechanisms can interfere with each other. Thus, thermohygric and moisture expansion are important damage processes.

Gastric ulcer is a common disorder of the digestive system. The combination of turmeric and honey is known to treat stomach ulcers. However, curcumin, an active component in turmeric, has limitations, i.e., poor water solubility and low oral bioavailability. Therefore, turmeric and honey were formulated into a nanoemulsion with black pepper to enhance curcumin bioavailability. The study followed a systematic approach to optimize the nanoemulsion formula, determine stability, and evaluate ulcer healing activity in rats with ethanol-induced gastric ulcers. Nanoemulsion was prepared using a low-energy emulsification method called emulsion phase inversion (EPI). Two stability evaluations were carried out, i.e., storage and freeze-thaw stability tests. The organoleptic, droplet size, polydispersity index, pH, viscosity, and curcumin content of the nanoemulsion were evaluated. Male Wistar albino rats were induced with 96% ethanol for six days. The rats were divided into six groups, i.e., healthy control, ulcerated control, omeprazole, two different doses of turmeric, honey, and black pepper nanoemulsion (NTBH1 and NTBH2), and turmeric and honey nanoemulsion (NTH). The antiulcer activity was determined by measuring the ulcer area, ulcer index, curative index, ulcer severity score, and histology. The best formula with the smallest droplet size, i.e., 144.6±3.8 nm, was obtained from the nanoemulsion using Tween 80 as surfactant, glycerin as cosolvent, and sodium alginate as viscosity enhancer. The result showed that the nanoemulsion was stable after being stored at 25 and 40°C for four weeks and after six cycles of freeze-thaw test. The ulcer index of the ulcerated rats from the lowest to the highest, i.e., NTBH2, omeprazole, NTH, and NTBH1. In conclusion, the nanoemulsion developed in this study containing turmeric, honey, and black pepper holds promising potential in treating gastric ulcers, offering a hopeful outlook for future treatments.

This study aims to promote the effective utilization of moderately weathered tunnel slag, preserve the ecological integrity of construction sites, and support sustainable development. An orthogonal experimental design was used to examine the effects of aggregate gradation, cement content, and curing age on the uniaxial compressive strength (UCS) of Cement-Stabilized Macadam (CSM) containing tunnel slag. Range analysis showed that CSM made with moderately weathered slag exhibits favorable mechanical properties. The optimal condition combination was Gradation C, 6% cement, and a curing age of 28 days. Analysis of variance (ANOVA) indicated that cement content and curing age significantly influenced UCS, with cement content having the greatest effect, followed by curing age. Gradation showed no statistically significant effect. Based on these findings, a series of UCS tests, indirect tensile strength (ITS) tests, and freeze-thaw tests were conducted to evaluate the impact of basalt fiber (0.07% by mass, 12 mm in length) reinforcement on the mechanical properties and frost resistance of CSM. The addition of basalt fibers slightly reduced UCS, from 7.08 MPa to 6.97 MPa, but significantly increased ITS, from 0.337 MPa to 0.374 MPa. Frost resistance also improved significantly. Post-freeze–thaw mass loss decreased from 0.121 to 0.095%, and residual compressive strength increased from 88.28 to 96.99%. Compared to existing studies, this research takes an initial step in exploring the reuse of moderately weathered tunnel slag and the synergistic effects of fiber reinforcement and slag on CSM performance. The findings contribute to cost-effective infrastructure development and provide notable ecological benefits, offering a useful reference for future engineering applications.