Moisture Damage Research Articles (Page 1)

The asphalt industry is increasingly urged to adopt sustainable practices by utilizing bio-based and recycled resources. This study evaluates the performance of warm mix asphalt (WMA) modified with chitosan derived from shrimp shell waste (SSPCH). Chemical characterization of modified bitumen was conducted using SEM and FTIR, while mechanical performance was assessed through Marshall stability, repeated load axial, indirect tensile strength (ITS), and semi-circular bending tests. Results identified an optimal SSPCH content of 6%. This modification significantly enhanced rutting resistance, reducing permanent strain by 38% compared to the control. The modified mixtures also met ASTM D4867 requirements, showing a 24.5% increase in ITS and a 23% improvement in Tensile Strength Ratio (TSR), indicating superior moisture damage resistance. The enhancement is attributed to SSPCH's physicochemical properties, which promote a stronger bitumen-aggregate bond. This research confirms SSPCH as a viable bio-additive for developing more durable and sustainable asphalt pavements.

This study investigates the freeze-thaw (F-T) durability and mechanical performance of Slurry Infiltrated Mat Concrete (SIMCON) produced with two different binders, Portland cement (CEM I 42.5R) and calcium aluminate cement (CAC). SIMCON composites were fabricated by infiltrating cement pastes into randomly oriented steel wool mats, aiming for improved fiber distribution and matrix-reinforcement interaction. Specimens were subjected to 0, 15, and 30 F-T cycles and evaluated on the basis of unit weight, ultrasonic pulse velocity (UPV), flexural strength, and compressive strength. The results showed that all properties deteriorated with increasing number of cycles; however, CAC-based composites consistently outperformed their CEM I counterparts. After 30 cycles, CAC specimens retained 54% higher compressive strength and exhibited slower deterioration rates in UPV and flexural strength. The superior performance of CAC is attributed to its denser, more stable microstructure and its improved resistance to internal cracking and moisture damage. These findings demonstrate that CAC is a promising binder for SIMCON in infrastructure and retrofit applications exposed to harsh environmental conditions where long-term durability is critical.

Enhancing Interfacial Adhesion and Moisture Damage Resistance in Asphalt Mixtures via Silane Coupling Agent: Moisture Damage Separation and Quantization

Due to the construction industry, the climate crisis had deepest environmental impact. In addition to consuming scarce mineral-based materials, the building industry is responsible for up to 39% of global carbon dioxide emissions and the accumulation of solid waste in landfills, rivers, and seas. To cut carbon dioxide emissions and mitigate the effects of climate change on the construction industry, a new, more sustainable, and renewable production matrix must be considered. An approach is using seaweed and seagrass as bio-based materials matrix, from macroalgae or microalgae stranded on the shore or sustainable crops. Transforming algae into usable construction materials involves a process of harvesting, processing, and refining. This article has systematically reviewed the literature about advances and the potential of using marine species as construction materials matrix. To this end, this paper explores the existing literature on architectural projects and research on various species of seagrass and seaweed worldwide. This review concludes that numerous case studies of dwellings around the world have demonstrated and validated the use of seaweed for applications such as coatings, thermal insulation, and construction additives. Among the most important construction related properties of seaweed are fire resistance, low thermal conductivity, and resistance to moisture and insect damage. For instance, prototypes incorporating Neptune grass (Posidonia oceanica) exhibited a thermal conductivity of 0.044 W/m·K comparable to that of expanded polystyrene, which typically ranges between 0.035 and 0.037 W/m·K. The availability of seaweed, considered the waste that pollutes an essential part of the world's coastline, is increasing every year. Nevertheless, not all types of seaweed can be used as construction materials. For this reason, there are some challenges in creating sustainable cultivation of seaweed species, like the need for efficient methods, harvesting, and its processing. In consequence, these costs must be incorporated into the selling price. However, these difficulties do not diminish the seaweed and seagrass's potential as a renewable substitute in the production matrix of the construction industry. These challenges must be overcome before the industrial use of marine species as building materials becomes a reality. Governments must provide financial support to get these initiatives off the ground, especially in the crucial pre-competitive phases. At the same time, the development of prefabrication systems is of vital importance. These systems will enable certification and compliance with building materials regulations and pave the way for a more sustainable future for the industry. It is also necessary to establish seaweed and seagrass cultivation methods that will make the initiative sustainable in the long term, incorporating the costs associated with cultivation, harvesting, and processing into the selling price.

Moisture damage of asphalt pavement has always been one of the major concerns for researchers in the pavement engineering field. Mitigating this moisture-induced damage is essential for improving pavement performance, extending service life, and reducing lifecycle costs. Several studies have reported that waste plastic can potentially increase the cohesion between asphalt and plastic molecules and enhance the adhesion between asphalt and aggregate, improving the moisture damage resistance of asphalt pavements. The present study aims to understand the effect of incorporating different waste plastics as modifiers on a binder’s fundamental properties, such as cohesive bond energies. To achieve this goal, three different waste plastics—high-density polyethylene (HDPE), polypropylene (PP), and polyethylene terephthalate (PET) in 2%, 4%, 6%, and 8% by weight of the total binder—were used to modify the conventional asphalt binder (PG 58-28). The surface free energy (SFE) was determined by depositing one polar and one non-polar liquid on the solid samples by using the liquid needle drop deposition technique while adopting three different theories. Finally, the cohesive bond energies of the modified asphalt binders were calculated. The results showed that waste plastics significantly increased the total SFE and cohesive bond energy of the asphalt binder up to 4% plastic addition and then dropped. Besides, the comparative analysis revealed that PP modification was most effective for improving moisture damage resistance among the three plastics. Therefore, the use of plastic waste for asphalt binder modification was found to be a promising approach for enhancing moisture damage resistance.

In response to global warming, climate change risk assessments for cultural heritage should be applicable not only to iconic sites but to all historic buildings. Risk assessments should function at the material, site, and regional scale. Increasing days of heavy precipitation will have severe impacts for historic buildings, for example stressing rain-water goods. To evaluate this hazard, changing occurrences of extreme precipitation events have been calculated for the UK with 1.5 °C and 3 °C of warming using the National Severe Weather Warning Service thresholds. By integrating the materials of the over 380,000 listed buildings in England, this assessment explores how moisture damage processes can be translated to thousands of sites, informing regional prioritisation.

Abstract This study provides a comprehensive evaluation of the performance of hot mix asphalt concrete incorporating sulfur waste (HMAS) as a partial replacement for bitumen binders during extended curing times, aiming to investigate the evolution of strength in asphalt concrete containing sulfur after paving and determine the effect of sulfur waste on the mechanical properties and performance of HMAS at later ages. The optimal binder content in asphalt concrete containing sulfur waste was determined for HMAS mixtures incorporating 30% and 40% sulfur as a replacement for the bitumen binder by weight. The optimal bitumen content used in HMAS using sulfur bitumen binder (SBB) was found to be within the range of 3.15–4.5% for SBB containing 40% sulfur and 3.5-5% for SBB containing 30% sulfur, which is lower than that in HMA without sulfur. Experimental results revealed that the Marshall stability of HMAS consistently increases over time and stabilizes after 14 days, whereas HMA does not exhibit this behavior. Recrystallized sulfur crystals formed a lattice in the pores and binders, reinforcing the structure and increasing the density and stiffness of the HMAS samples after 14 days, which led to improving the mechanical properties of HMAS at later ages. However, HMAS exhibits sensitivity to moisture even at later ages, and HMAS containing 30% sulfur demonstrates higher moisture resistance compared to that containing 40% sulfur. The moisture sensitivity of HMAS containing a high amount of sulfur is attributed to the agglomeration and recrystallization of sulfur crystals in asphalt concrete at later ages. Based on the experimental results, an engineering solution was proposed for using HMAS in flexible pavements to prevent moisture damage. The HMAS layer is sandwiched between two layers of hydrophobic (waterproofing) materials in the flexible pavement structure and the HMAS layer should be placed beneath the wearing course (surface course). The performance calculation of the pavement structure with the HMAS layer demonstrates a superior load-bearing capacity compared to the structure using only HMA. The proposed pavement structure has the potential to incorporate a large amount of sulfur in asphalt concrete pavement, contributing to sustainability in pavement engineering.

Moisture damage is a critical issue that deteriorates the asphalt pavement, diminishes the road's longevity, and increases the likelihood of road failure. This study investigates the impact of epoxy resin, recognized for its strong adhesive properties, on the moisture resistance of asphalt mixtures by incorporating three ratios: 5%, 10%, and 15%. The Marshall, Tensile Strength Ratio (TSR), and Index of Retained Strength (IRS) tests were conducted to assess the influence of the epoxy resin on the asphalt performance. The results indicated that the Marshall characteristics, as well as the asphalt mixture's water resistance were enhanced. A 10% epoxy resin ratio was found to be the optimum content. The Marshall stability improved by 37.86 %, the TSR by 9%, and the IRS by 6.58%, relative to the original mixture. Epoxy resin supports the environmental sustainability by increasing the pavement resilience, which reduces the maintenance and reconstruction needs, lowers the carbon emissions, minimizes waste, and encourages the efficient use of resources.

The current study assessed the effectiveness of five conventional and three hermetic storage facilities for extended storage of wheat grains under ambient storage conditions during two storage seasons (2023 and 2024). The findings indicated that hermetic storage facilities outperformed conventional ones throughout the six-month storage period. For instance, GrainPro PHB exhibited the minimal increase in grain moisture contents (0.50 and 0.33%), resulting in the least grain damage (2.38 and 2.44%) and weight loss (0.93 and 0.93%) during both years, respectively. Additionally, GrainPro PHB recorded the highest seed germination (90.50 and 90.33%) for both years. Compared to conventional storage methods, GrainPro PHB exhibited a lower number of storage insects. The proximate composition analysis revealed significant nutritional differences between polypropylene bags and GrainPro PHB. GrainPro PHB successfully maintained proximate composition, with minimal decreases in protein (1.03 and 0.71%), fat (16.88 and 14.95%), and starch content (0.8 and 0.5%) and minimal increases in ash (25.00 and 23.33%) and fiber contents (18.33 and 16.80%) in both years. Moreover, results revealed a positive correlation between grain moisture contents and damage parameters, suggesting that the higher moisture contents may aggravate the percent grain damage and weight loss. There were also better rheological properties in flour made from grains stored in GrainPro PHB, like a lower minimum water absorption capacity (WAC), a longer dough development time (DDT), and a maximum dough stability time (DST). Furthermore, texture profile analysis (TPA) of bread made from flour of grains stored in GrainPro PHB showed improved texture, with higher chewiness, cohesiveness, springiness, and resilience, and lower hardness, resulting in superior overall quality compared to bread made from conventionally stored grains. Eventually, these findings underscore the effectiveness of hermetic storage facilities in maintaining grain moisture contents, reducing losses, preserving seed quality, and enhancing food and nutrition security.

This study evaluated the relative effect of different modifiers and antistripping additives on the rheological properties of asphalt binder PG 58-28, commonly used in Newfoundland and Labrador, Canada. Four antistripping additives: ZycoTherm SP2, Kling Beta 2914, Pave Bond Lite, and AD-Here were used at different dosage rates for laboratory investigations. These antistripping additives were blended to a styrene-butadiene-styrene (SBS) polymer and Gilsonite modified binder. Later, all binders were aged using rolling thin film oven (RTFO) method. The rutting and cracking parameters, such as the Superpave rutting parameter, Shenoy’s rutting parameter, non-recoverable creep compliance, crossover frequency, rheological index and Glover-Rowe parameter were evaluated for SBS and Gilsonite modified binders. Comparative rutting parameters analysis showed that both SBS and Gilsonite modified binders enhance the rutting performance of the asphalt binder. Additionally, the moisture damage test from the surface free energy test and cracking test revealed that the antistripping agent with SBS-modified binder performed better than the Gilsonite-modified binder.

Effect of amine-based and chemical WMA additives on moisture damage resistance of asphalt mixtures at different conditioning protocols

The open-graded friction course, called FC-5, is widely used in Florida to enhance safety. However, the FC-5 layers on suburban roads are prone to premature raveling as a result of increased lateral stresses from turning, braking, and rapid acceleration. This study, therefore, aimed to develop a more durable alternative friction course (AFC) for suburban roads that would have minimal impact on permeability and surface friction. The AFC mixture was designed based on the FC-5 and 12.5 mm stone matrix asphalt (SMA) mixtures. Specifically, the gradation of AFC was designed to be finer than the FC-5 to improve durability but coarser than the SMA to ensure permeability. All three mixtures (FC-5, AFC, and 12.5 mm SMA) were prepared with two aggregate types (limestone and granite) and two asphalt binders (PG 76-22 and high polymer modified binder). Laboratory tests, including the Cantabro, Hamburg wheel tracking, overlay, Florida permeability, outflow meter, circular track meter, and dynamic friction tests, were performed to comprehensively evaluate the durability and functionality of the three mixtures. The laboratory results showed that AFC mixtures demonstrated better friction, durability, and resistance to cracking, rutting, weathering, and moisture damage than FC-5 mixtures while maintaining adequate permeability and drainability. Notably, AFC mixtures showed comparable durability and cracking resistance to SMA mixtures. Based on these laboratory findings, the preliminary AFC design requirements were proposed, including a gradation band, an air void range of 10% to 15%, and a maximum Cantabro loss of 10%.

This research investigates the influence of waste mask fabric scraps (WMFSs) and nano-carbon-modified filler (NCMF) on the mechanical characteristics and durability of hot mix asphalt, aiming to improve pavement performance concerning tensile stress, fatigue, and moisture damage using recycled materials. Asphalt mixtures were created with aggregate and WMFS/NCMF at 0.3% and 0.5% weight percentages (relative to aggregate), with fiber lengths of 8, 12, and 18 mm, utilizing a ‘wet mixing’ method where fibers were incrementally added to aggregates during mixing. The samples underwent indirect tensile strength, moisture susceptibility, and Marshall stability testing. The results demonstrated that incorporating WMFSs and NCMF initially enhanced tensile strength, moisture susceptibility resistance, and Marshall stability, reaching an optimal point; beyond this, further fiber addition diminished these properties. Data analysis identified the sample containing 0.3% fibers at a 12 mm length as the superior performer, showcasing the highest ITS and Marshall stability values. Statistical t-tests revealed significant differences between fiber-containing samples and control groups, verifying the beneficial impact of WMFSs and NCMF. Design-Expert software (Design-Expert 12.0.3) was used to develop functional models predicting asphalt properties based on fiber percentage and length. The optimal combination—12 mm fiber length and 0.3% WMFS/NCMF—demonstrated a 33% increase in tensile strength, a 17% improvement in moisture resistance, and a 70% reduction in fatigue deformation. Safety protocols, including thermal decontamination of WMFSs, were implemented to mitigate potential health risks.

This research provides useful insights into sustainable and cost-effective pavement rehabilitation by evaluating the combined effects of both Reclaimed Asphalt Pavement (RAP) and Crumb Rubber (CR) modification on flexible pavement performance using actual motorway sections. Pavement rehabilitation and maintenance can enhance the design and serviceable life of the pavement. Additionally, modification of asphalt with Crumb Rubber (CR) and Reclaimed Asphalt Pavement (RAP) not only proves to be economical but can also increase the resistance of flexible pavement concerning rutting, fatigue, and moisture damage. Four different pavement sections were selected, which were rehabilitated and modified with Reclaimed Asphalt Pavement (RAP), Crumb Rubber (CR), and a combination of both, along the Islamabad-Lahore motorway (M-2), Pakistan. The first pavement section consists of Asphalt Concrete Wearing Course (ACWC) with 60/70 grade bitumen as a binder (RAP 0%, CR 0%), the second pavement section was a mixture of asphalt concrete with crumb rubber modified bitumen as a binder (RAP0%, CR7%), the third pavement section was a blend of 15% RAP with 60/70 grade bitumen as a binder (RAP15%, CR 0%), the fourth section was a mixture of 15% RAP and 7% crumb rubber modified bitumen (RAP 15%, CR 7%). Pavement cores were extracted from the selected four pavement sections, which were experimentally explored in the laboratory to find the impact on the performance of highway pavement employing Reclaimed Asphalt Pavement (RAP) and Crumb Rubber (CR), partially replacing bituminous binder in the asphalt. The results show notable improvements in rutting resistance, tensile strength, and resilience. It was concluded that the performance of the section employing either RAP, CR or combined RAP and CR modified bitumen better enhanced the performance of pavement in terms of rut depth, indirect tensile strength and modulus of resilience. For instance, rutting depth was reduced by 41.35% and indirect tensile strength of pavement was increased by 17.93% by employing 15% RAP and 7% CR in modified bitumen binder for asphaltic mix. Likewise, the modulus of resilience was increased by 38.23% for the section employing 15% RAP and 7% CR in pavement.

Abstract Failures of structural elements in historical roof trusses pose a significant challenge in the preservation and restoration of a cultural heritage. These trusses, traditionally constructed from wood, are exposed to various factors that contribute to their degradation and damage. The most common factors include moisture, insect activity, fungal decay, and mechanical damage caused by geometric deformations or unprofessional alterations. These defects can compromise the structural integrity of an entire roof truss construction and jeopardize the stability of the building. The restoration and conservation of historical roof trusses require a specialized approach involving detailed diagnostics, modern technologies, and the preservation of original construction elements. This paper focuses on identifying the most common structural defects in historical roof trusses, analysing their causes, and presenting possible repair methods aligned with the protection and care principles of a heritage.

Assessing and enhancing moisture damage resistance of tuff-asphalt interface: A hydrodynamic fatigue pull-off test approach

Predictive modeling of moisture damage in recycled asphalt mixtures: evaluating chip content and rejuvenating agents

Asphalt pavement performance is based on several parameters and properties of the materials’ element. surface free energy that the modifier and the asphalt binder both displays. The resistance of the modified asphalt binder to stresses and moisture damage is largely determined by the bond energies. Asphalt binder qualities may be altered by either technical or natural processes, which subsequently impact on the chemical and mechanical characteristics. In addition, a correlated investigation revealed that surface free energy values may be used to assess the compatibility of a binder in relation to moisture-induced damage. Data demonstrates that the incorporation of soft clay into the asphalt binder resulted in a favorable coating and bonding capacity, as compared to the control asphalt binder. moisture-induced damage in HMA is a combined effect of loss of cohesion of asphalt binder and loss of adhesion between asphalt binder and aggregate. It was indicated that the modified binders of BPSC ratios would delay and weaken the oxidation reaction asphalt binder which can enhance the aging process. Based on absorbance peaks of carbonyl and sulfoxide bonds, the addition of BPSC would delay the aging process of asphalt binder.

The current Ethiopian policy is to strengthen mechanization to improve crop production. The economy depends on agriculture, and the technology imported challenges Ethiopian inducers. The best option is the strength of local manufacturers and artisans. The purpose of this training was to strengthen the artisan and youth groups to improve fabrication quality. The training was conducted on fabrications of maize sheller and metal silo at Melkassa Agricultural Research Centre. The parts of Sheller are: supporter, drum, engine, shaft, chain, and sprocket. The sheller parameters are: speeds, moisture, shelling capacity, efficiency, and grain damage. Metal silo designs parameters: diameter of silo, height, thickness, and density of crop. The material used was galvanized sheet metal (28 gauge), lead, acid, and benzene. The trainers come from Oromia, Amhara, Central Ethiopia, Sidama, and the South Ethiopia region. They equally participated in maize sheller and metal silo fabrication. Oromia and Amhara (28%), Central and South Ethiopia (17%), and Sidama (10%) of the artisans successfully participated. They cover theoretical and practical sessions, and they can fabricate quality sheller and metal silos. After the training, they can develop their business, and it results in the minimizing of crop as it improves the accessibility of the technologies. Ethiopia's policy aims to improve crop production through mechanization, focusing on local manufacturers and artisans. A training program was conducted at the Melkassa Agricultural Research Centre to improve fabrication quality of maize shellers and metal silos. The training involved trainers from various regions, with 28% of participants successfully participating. The training helped artisans improve their skills, leading to business development and reduced crop loss, thereby enhancing technology accessibility.

To further improve the asphalt performance, polyurethane (PU) prepolymer and SBS were used in this paper to prepare modified asphalt through physical–chemical composite modification. The physical performance and rheological properties of the modified asphalt was tested to evaluate the improving effect. And the asphalt mixtures performance was evaluated. The results indicated that the physical–chemical composite modification could significantly improve the physical performance and rheological properties with the recommended dosage of 5% SBS and 4% PU prepolymer. The modified asphalt exhibited excellent rutting resistance and elasticity recovery and good cracking resistance. In the composite modification process, PU could improve the compatibility of the modified asphalt system, which in turn improved the mechanical performance and storage stability. The PU-SBS composite modified asphalt mixture had good high-temperature and low-temperature performance, and moisture damage resistance. These results provided valuable theoretical insights for further research and application of physical–chemical composite modified asphalt.