Content
- Mechanical properties and damage characterization of cracked granite after cyclic temperature action
- Freeze-Thaw Study in Drug Products
- Wrapping It Up With a Bow: The Gift of Protected Concrete
- Triaxial tests on soil samples experiencing freezing–thawing cycles
- Numerical analysis of stress and deformation on soil slope subjected to thawing–thawing actions
- Effects of Freezing and Thawing on the Consolidation Settlement of Soils
- Tip #4: Keep Snow Clear to Minimize Moisture
- 2 Expansion mechanism of natural geomaterials
Additionally, investigating how different rock types respond to freeze–thaw cycles will offer a broader perspective on the impact of these processes on various geological materials. Advanced models incorporating dynamic loading conditions and real-world stress scenarios should also be developed to enhance the prediction and mitigation of freeze–thaw damage in engineering applications. In general, the compressive strength of rock materials is much greater than the tensile strength, and in most cases, the damage behavior of engineering rock masses indicates their tensile damage characteristics52. The tensile strength is an important index to evaluate the mechanical properties of rock masses, while the tensile damage is the main form of damage to rock masses.
Mechanical properties and damage characterization of cracked granite after cyclic temperature action
- The prepared specimens were placed in an environmentally controlled desiccator, with water placed underneath to facilitate wetting through vapour adsorption till it reached the lower suction.
- Liu et al. (2017) identified frost heave in coarse-grained soils when specific combinations of clay content (the mass fraction of the particle with a diameter less than 0.075 mm), initial moisture, and temperature occurred in seasonal frozen regions.
- SF values closer to 1 indicate a more regular pore shape (i.e., closer to a spherical shape), and smaller values refer to more irregular or elongated pore shapes (Zhou et al., 2012).
- By preventing the propagation of microcracks and reducing permeability, these NRL films provide a robust barrier against freeze-thaw cycles (Udomchai et al., 2021; Hoy et al., 2023).
- Such high electrolyte concentrations disrupt the hydration shell around protein molecules by causing water around them to move into the bulk solution and thereby exposing the hydrophobic regions.
Most existing research on freeze–thaw conditions in rocks focuses primarily on compression or shear characteristics, while studies on the coupled tension–compression–shear (T–C–S) state remain relatively limited. This becomes particularly important in complex stress environments, such as those involving repeated freeze–thaw cycles, where the stress state of rock masses requires careful evaluation. Developing a T–C–S joint strength model is crucial for evaluating the stress state of slopes under long-term freeze–thaw conditions, especially in high-locality landslides. The results validate that the UCS of biochar-amended soils declines significantly following one or third cycles of freeze-thaw action, with subsequent cycles showing a minor influence. The decrease in the UCS value of BAS was observed because it underwent microstructural changes due to ice expansion and contraction during F-T cycles.
- A sustainable solution is recycling waste materials, such as bamboo waste, into biochar would be essential, advantageous, cost-effective, and beneficial for the environment4.
- This information will have implications for the larger, global ecosystem that will become immediate as the climate warms.
- Variation of GWC under unconfined and confined condition at different suctions levels of (a) CL soil and (b) SM soil, mixed with increasing BB content.
- Experimented on the pore morphology of clay minerals and concluded that the swelling phase did not only relate to the clay mineral type, but also to the pore morphology.
- The compressive strength of both CL and SM soils decreased with increasing freeze-thaw cycles, with 2% BB-amended soils showing strength reductions of 29.32–40.22% for CL and 28.52–43.76% for SM soils from the first to the third freeze-thaw cycle.
- These changes include increasing variability in winter air temperature and the resulting increase in freeze-thaw cycles.
Freeze-Thaw Study in Drug Products
The strength behaviour under prolonged curing periods and increasing freeze-thaw cycles is missing for BAS specimens. There is also a notable lack of studies exploring the correlation between compaction efforts and the soil-water retention characteristics of BAS. Hence, this study focused on the existing research gap and significant contribution to the potential utilization of BAS in geo-environmental engineering applications. Studies have discussed the osmotic pressure theory, which involves specific salt ions in concrete (Powers, 1949; Powers et al., 1953; Powers, 1975; Hudec, 1991; Valenza and Scherer, 2007).
Wrapping It Up With a Bow: The Gift of Protected Concrete
These trends were similar to the curing results, wherein the addition of BB resulted in a notable increase in UCS of CL soil upto 2% BB content and decreased after that. Thus, the results showed that smaller (1% and 2%) BB-amended CL soil experiences a milder impact from F-T cycles than non-amended and soil amended with higher BB concentrations (3.5% and 5%). In contrast, biochar-amended SM soil showed a consistent decrease in UCS value with the addition of BB ranging from 1 to 5%, for all F-T cycles. In BB-amended SM soil, the UCS was higher at lower BB content and lower at higher BB content for the same F-T cycle. These patterns imitate those observed in the curing tests, where the addition of BB led to a significant reduction in UCS of SM soil. Moreover, in all scenarios, the UCS of biochar-amended soils diminishes after being subjected to F-T action.
Triaxial tests on soil samples experiencing freezing–thawing cycles
If your gutters are overflowing or downspouts direct water toward concrete surfaces, it can increase the moisture available to freeze inside and under your slabs. Freeze-thaw cycles don’t just affect the concrete slab itself—they can also disrupt the soil or sub-material below, causing your concrete to shift and settle as it loses the solid support beneath it. When temperatures rise again, that water thaws, leaving larger empty pockets within the concrete where the pores have popped. The stability data available to-date demonstrate that the high protein concentration and reduced sodium chloride formulation continues to meet the target criteria for the quality attributes tested at the long-term storage conditions (Table 7). No significant changes in the purity of the mAb-1 has been observed by chromatographic and electrophoretic methods of SE-HPLC, CE-SDS, and peptide mapping over time when stored at the intended long-term storage condition. The structural integrity of the glycans, the potency, appearance, pH, and content of mAb-1 were also maintained.
Numerical analysis of stress and deformation on soil slope subjected to thawing–thawing actions
We are comparing soil aggregate stability, carbon quality, microbial activity, and mineral composition in samples that were frozen versus samples that underwent freeze-thaw. Our team hopes to gain insight into how freeze-thaw cycles increasing in both frequency and intensity on soil will impact the soil ecosystem. This information will have implications for the larger, global ecosystem that will become immediate as the climate warms. The freeze-thaw defect in concrete occurs when water within the concrete freezes and expands, leading to the formation of ice crystals. When temperatures drop, the water within the concrete freezes and expands, exerting pressure on the surrounding concrete matrix and causing microcracks to form. Upon thawing, the ice melts, but the concrete may not fully return to its original state, leaving behind residual stresses and weakened areas.
Effects of Freezing and Thawing on the Consolidation Settlement of Soils
The GWC at lower suctions (500 kPa) and higher suctions (180 × 103 kPa) also plays a role in determining the overall water availability and plant growth in soil ecosystems. The fluctuations in GWC of BAS at lower suctions (500 kPa), PWP (1500 kPa), and higher suction (180 × 103 kPa) were also observed, as illustrated in Fig. Strength variation under freeze thaw condition of BB-amended CL UCS specimens cured for 30 days with varying (a) BB percentage and (b) the number of freeze-thaw cycles. The alteration in pores size and development of bonding between soil-BB in the UCS specimen cured for 30th day for (a, c) non amended CL, SM soil; and (b, d) CL, SM soil mixed with 2% (w/w) biochar content. https://progorki.com/engineering-perspectives/advantages-of-modular-pools/ were collected from two distinct locations within the Patna district in Bihar, India. Have you ever seen a heavy, solid rock that’s been seamlessly broken into thin plates by some invisible force? Or have you observed those eerily perfect circular patterned rock formations along mountain slopes? Maybe you’ve noticed mysterious, repetitive mounds scattered through the countryside in the middle of fields. Figure 6 presents the XRD results for non-amended and 2% BB-amended CL and SM UCS specimens cured for 30 days. The mineralogical analysis of CL and SM soils showed no significant changes after the 30-day curing period (Fig. 6a and b). However, after this curing period, the 2% BB-amended CL and SM UCS specimens exhibited new peaks of carbonate minerals, as shown in Fig. The mineralogical analysis confirms that the CHS compounds observed in the FESEM images were due to the formation of carbonate minerals in the BAS, which contributed to the increase in UCS strength over the curing period in both soils. In conclusion, the existing literature suggests that the strength and water retention characteristics vary with biochar types5, and the application of bamboo biomass-based biochar for landfill cover layer remains underexplored, highlighting a significant gap in research.
Tip #4: Keep Snow Clear to Minimize Moisture
This expansion can enlarge fractures and void spaces in geomaterials and concrete structures during the thawing process, which can contribute to structural instability in these regions. Natural expansive geomaterials with high shrink-swell potential play a crucial role in geotechnical engineering. These materials exhibit unique properties that can significantly affect infrastructure stability and environmental concerns. Therefore, this section discusses the significance and implications of clay minerals and sulfate minerals in geotechnical engineering, drawing upon relevant research and findings. To mitigate cracking in concrete due to freeze-thaw cycles, an effective method will be to reduce hydrostatic pressure by decreasing the spacing between pores. This may be accomplished through the use of air-entraining agents, which introduce tiny air bubbles into the concrete mix.
2 Expansion mechanism of natural geomaterials
Physicochemical properties of soils, BB and BAS
The measured samples were accurately compressed to their 0.9MDD level, as presented in Table 2. These approaches will enable geotechnical engineers to predict material behavior, identify internal mechanisms, and develop strategies to minimize the impact on geo-infrastructure, resulting in safer and more resilient construction. There is a knowledge gap regarding how the expansion, shrinkage, and chemical reactions of sulfate minerals in geomaterials and cemented infrastructures can induce significant reinforcements under varied loading and environmental conditions. The influence of expansive natural materials on geo-infrastructures can be profound, often resulting in foundation cracks, structural tilting, and compromised integrity. The waste generated by the agricultural sector is commonly found in many regions worldwide1. Bamboo plays a vital role as a structural and load-bearing element in various applications, including fencing, construction, roofing, and craftsmanship, particularly in developing countries such as India, China, and Malaysia. Despite its extensive use, only 30–40% of the global bamboo supply is effectively utilized, leading to the disposal of the remaining portion as waste through burning or burial3. A sustainable solution is recycling waste materials, such as bamboo waste, into biochar would be essential, advantageous, cost-effective, and beneficial for the environment4.
