Freeze-Thaw Effects on Steel Structures

Content

• Understanding Freeze-Thaw Stability Testing
• Mechanical properties and damage characterization of cracked granite after cyclic temperature action
• 2.2 Sulfate mineral expansion behavior
• 2 Impact of sulfate attack on cemented structures
• Eng-Tips is the largest forum for Engineering Professionals on the Internet.
• Freeze-Thaw Damage in Concrete: Causes and Mitigation Methods
• Soil temperature changes during the freeze-thaw period and the carry-over effects of freeze-thaw on soil nutrients
• Analysis on test results

These cycles have exaggerated volume fluctuations in BAS, resulting in internal stresses that reduce the UCS. The pores and voids generated by biochar particles in BAS facilitated ice penetration and expansion during freezing, compromising the matrix structure and damaging strength. Table 5 provides a summary of various natural expansive materials, highlighting how their expansion behavior can affect geo-infrastructure. The analysis indicates that clay mineral expansion, influenced by factors such as moisture content and volume increase, leads to shrink-swell behavior and can cause significant damage to foundations. Additionally, solutions available at ProGorki in cemented structures causes concrete expansion and deterioration through reactions with hydration products like gypsum and ettringite.

It was identified that mAb-1 was susceptible to F/T stress and significant aggregation was observed when subjected to fast freezing and slow thawing as compared to slow freeze and fast thaw. The extent of aggregation increased multifold after additional cycles of fast freeze and slow thaw (Table 2). Based on our extensive understanding of the molecule, it was hypothesized that it is most likely that slow thawing is contributing to aggregate formation.

Mechanical properties and damage characterization of cracked granite after cyclic temperature action

The movement of both rocks and soil are controlled by freeze and thaw, creating mounds, organizing rock circles, and cracking the rocks themselves. These phenomena are macro views of the freezing and thawing that naturally occurs in soil. Expansive clay minerals (notably montmorillonite) are widespread in both humid and arid regions which pose significant geotechnical hazards, surpassing damages caused by natural disasters. The expansion mechanism of clay minerals, driven by hydration energy and water absorption into interlayer spaces and crystal lattices is complex which makes it difficult to control water movement in underground excavation and foundation engineering. Gypsum plays a crucial role in cement manufacturing by preventing or slowing down the rapid setting of cement particles, a phenomenon known as flash setting (Aakriti et al., 2023).

• The detailed procurement procedure for soils and biochar are presented in the past article19.
• If the lateral displacement was kept constant, the height of the soil sample experiencing freezing–thawing cycles may become larger, and soil samples have large volumetric expansion.
• The procedure for image analysis was similar to that described by Wang and Hu (2023) (Fig. 3).

However, the number of comprehensive studies exploring the efficiency of gypsum in soil stabilization remains relatively limited, with notable contributions from researchers (Yilmaz and Civelekoglu, 2009; Kiliç et al., 2015). In contrast, combining gypsum with other materials offers a wide range of applications in the construction industry. For instance, fly ash-lime-gypsum bricks are used as a substitute for traditional clay bricks in construction, and their application contributes to soil conservation, pollution reduction, and an increase in the consumption of fly ash and gypsum (Jayasudha and Niranjan, 2014). Alonso (2012) conducted softening and swelling experiments of clay-containing anhydrite rocks under the effect of water evaporation and studied the effect of sulphate concentration in solution on swelling. Pore morphology substantially influences the swelling behavior of clay minerals (Sarman et al., 1994).

2 Impact of sulfate attack on cemented structures

Particularly, protein Aggregation is an issue that can be detrimental to data quality. Determining protein stability and quality first can therefore save both time and money e.g. in subsequent screening campaigns. NanoTemper’s instrument Tycho NT.6 (see Tycho NT.6 on nanotempertech.com) can be used to determine optimal handling conditions by quantifying the fraction of unfolded protein in a sample within seconds.

Based on the peak strengths obtained from the Brazilian test, uniaxial compression test, and triaxial compression tests, the tensile–compressive–shear (T-C-S) Mohr–Coulomb (M-C) strength envelope was constructed for granite under various freeze–thaw conditions. Assuming a linear strength envelope, the shear strength parameters (cohesion c and internal friction angle φ) and the theoretical tensile strength (σt) of granite were determined. This was achieved through linear backward extrapolation of the T–C–S M-C strength envelope (represented as a dashed line) to its intersection with the horizontal axis, thereby obtaining the corresponding theoretical tensile strength values (Fig. 10). A notable discrepancy was observed between the empirically measured tensile strength and the theoretical predictions based on the linear extension of the M-C strength envelope.

Freeze-Thaw Damage in Concrete: Causes and Mitigation Methods

If water can’t seep in, it can’t freeze inside your concrete, which causes damage as it freezes and expands. Freezing water that expands within concrete pores forces small cracks to form, and over time, these cracks widen and spread. Without proper care, these changes could turn your concrete surfaces into a winter wonderland of damage. While you’re sipping hot cocoa and watching the snow fall, your concrete is expanding and contracting, potentially paving the way for cracks, spalling, and settling from relentless freeze-thaw cycles.

Soil temperature changes during the freeze-thaw period and the carry-over effects of freeze-thaw on soil nutrients

The crucial requirement of molecular genetic methods is high-quality input material. The key question is "how to preserve DNA during long-term storage." Biobanks are recommended to aliquot isolated DNA into provided volumes. The aim of this study was to analyse the effect of repeated freezing and thawing on the genomic DNA integrity, quality and concentration. The aliquoted DNA isolated from blood cells using the automatic MagNA system and manual salting out method underwent freeze/thaw cycles at different storage conditions (-20 °C, -80 °C and liquid nitrogen). The average initial concentrations were 270.6 ng/μl (salting out method) and 125.0 ng/μl (MagNA).

It can also be applied to nitrogen management and productivity improvements in wetlands. Initial formulation development studies demonstrated that mAb-1 was susceptible to F/T stress resulting in soluble aggregate formation. The aggregates are likely the result of protein unfolding during freezing and subsequent association of unfolded molecules via covalent linkages.

The displacement-based loading mode was utilized at a constant rate of 0.5 mm/min. Test data was acquired at an interval of 1 s, which well facilitates the analysis of peak strength and stress–strain curves of the granite after freeze–thaw cycles. Rocks are normally in a compressed state, and rock damage is commonly understood to be compression-shear failure, in which shear force primarily causes rock grains to slide over the damaged surface40. Nevertheless, damage appears differently in rocks affected by freeze–thaw cycles, especially those that are 50 cm or less below the surface41,42. In some high-locality landslides on the Eastern Tibetan Plateau, cracks extending up to 200 m are often observed along the edges, indicating a combination of shear and tensile failure. Identifying the failure state becomes particularly challenging under the influence of repeated freeze–thaw cycles and complex stress conditions43.

Mitigating Delayed Ettringite Formation in Concrete Buildings and Structures

When soil layers freeze, pore water movement is transferred from unfrozen areas to negative regions, which leads to the expansion of the soil’s volume and the development of negative pressure (Beskow, 1991; Black and Hardenberg, 1991; Osokin et al., 2000). In these cold regions, pore water crystallizes and forms ice in the pores, sometimes forming ice lenses (Konrad and Morgentern, 1980; Kozlowski and Nartowska, 2013; Schreiber, 2014). This phenomenon can lead to significant frosts and a decrease in the engineering properties of the soil. In cold climates, the cyclic freezing and thawing processes strongly influence the durability and performance of geo-infrastructures (Tian et al., 2019).