Capillary Water Research Articles

Rapid assessment of water phase trapping on gas permeability reduction in typical tight gas reservoirs in China

Water phase trapping (WPT) is one of the primary formation damage issues which can cause a steep drop in tight gas production. This paper presented a rapid assessment of the damage potential of WPT in Daniudi, Nanpu 5th, and Keshen 9th tight gas reservoirs involving shallow to ultra-deep layers in China. Typical core samples of the three tight gas reservoirs were selected to perform water imbibition and drainage experiments to mimic the WPT occurrence. After that, the damage degree to core gas permeability induced by WPT was evaluated. Results showed that, for a 16-h vertical water imbibition experiment, the core samples of Daniudi gas reservoir experienced the fastest water imbibition process while the core samples of Keshen 9th gas reservoir established the highest water saturation. After water removal, the ranges of damage degree to core gas permeability induced by the incremental water saturation were 36.07%–78.13%, 36.06%–56.21%, and 61.00%–76.30% in Daniudi, Nanpu 5th, and Keshen 9th tight gas reservoirs, respectively. It found that with the increasing formation depth, tight gas reservoirs can suffer greater damage from WPT not only because of the decline in rock permeability but also the salting out of high salinity formation water. In general, it holds that strong water capillary imbibition phenomenon, low water removal capacity, and high gas permeability damage degree are found to be the striking features of WPT potential on these typical tight gas reservoirs in China.

Additive construction using enhanced earthen-based composites: Improvement of the mechanical strength and water durability using chitosan and agave fibers

3D printing has emerged as a revolutionary technology with potential applications in the construction industry. However, the prevalent use of ordinary cement in most 3D printing formulations results in significant greenhouse gas emissions during 3D printing construction. In contrast, earthen-based composites are an eco-friendly alternative for building materials. However, as a construction material, earth presents poor mechanical strength and low durability against water erosion. This study aims to obtain earthen-based composites with suitable mechanical and durability properties to investigate their extrudability and buildability in tests. It also explores the effects of incorporating short sisal fibers (l/d ratio = 138.7) and chitosan (DD = 91%, Mw = 598 kDa) to improve strength and water durability in earthen-based composites for 3D printing purposes. Chitosan is a natural macromolecule derived from a waste product from the food industry, whereas sisal fibers are obtained from the Agave sisalana plant. The change in compressive strength was analyzed through uniaxial compression. Water durability was evaluated by measuring the water contact angle, total and capillary water absorption, and accelerated erosion tests. The results indicate that the use of 3.0% (w/v) aqueous solution of chitosan and 1.0% (w/w) of sisal fibers have an important effect on the hardening and water durability properties of earthen-based composites. This study suggests that these materials could serve as natural additives to enhance the mechanical properties and water durability of new eco-friendly construction materials for 3D printing. In conclusion, this study demonstrates that appropriate formulations with natural and eco-friendly additives can lead to stabilized earthen-based composites with suitable printing, mechanical and durability properties for 3D printing applications in construction materials.

Suitability of Vetiver straw fibers in improving the engineering characteristics of compressed earth blocks

Although conventional earth construction has been replaced by modern materials in industrialized nations over the last century, interest in earthen materials has surged in industrialized countries due to their economic, social, and environmental sustainability benefits. Compressed earth blocks (CEBs) have gained popularity for their energy efficiency and lower greenhouse gas (GHG) emissions compared to fired clay bricks or cement concrete (CC) blocks. This research explores the potential of Chrysopogon zizanioides, commonly known as Vetiver, a perennial grass found in tropical and subtropical regions, to enhance the engineering properties of CEBs. While the use of Vetiver roots for soil erosion prevention and slope stabilization is well documented, the impact of Vetiver straw fibers on CEBs has not been sufficiently researched. Here, CEBs were manufactured with varying Vetiver straw fiber contents (0%, 0.5%, 1%, 1.5%, 2%, 2.5%, and 3% by dry soil mass). The physical properties of the Vetiver straw fiber-reinforced CEBs revealed a reduction in bulk density and volumetric shrinkage. As for the strength-ductility behavior, the Vetiver straw fibers noticeably increased the ductility of the CEBs. However, the rise in strength was not significant, and it showed little change over time. Durability characteristics were assessed through capillary water absorption and wear resistance tests, indicating reduced water absorption and enhanced wear resistance in CEBs with Vetiver straw fibers. Microstructural analysis through scanning electron microscopy reveals a more uniform and isotropic soil matrix with fewer voids, indicating stronger bonding between the fibers and the soil. Overall, Vetiver straw fiber has demonstrated its potential as a valuable reinforcement material for CEBs, making them more sustainable and resilient.

Properties of ultra-high-performance self-compacting fiber-reinforced concrete modified with nanomaterials

Abstract Utilizing waste materials to produce sustainable concrete has substantial environmental implications. Furthermore, understanding the exceptional durability performance of ultra-high-performance concrete can minimize environmental impacts and retrofitting costs associated with structures. This study presents a systematic experimental investigation of eco-friendly ultra-high-performance self-compacting basalt fiber (BF)-reinforced concrete by incorporating waste nanomaterials, namely nano-wheat straw ash (NWSA), nano-sesame stalk ash (NSSA), and nano-cotton stalk ash (NCSA), as partial substitutes for Portland cement. The research evaluates the effects of varying dosages of nanomaterials (ranging from 5 to 15% as cement replacements) in the presence of BFs. Rheological properties were analyzed, including flow diameter, L-box, and V-funnel tests. Additionally, the study investigated compressive, splitting tensile, and flexural strengths, load-displacement behavior, ultrasonic pulse velocity, and durability performance of the ultra-high-performance self-compacting basalt fiber (BF)-reinforced concrete (UHPSCFRC) samples subjected to sulfate attack, freeze-thaw cycles, autogenous shrinkage, and exposure to temperatures of 150, 300, 450, and 600°C. Microstructural characteristics of the mixtures were examined using X-ray diffraction (XRD) analysis. The findings reveal that self-compacting properties can be achieved in the UHPSCFRC by incorporating NWSA, NSSA, and NCSA. The presence of 10% NWSA significantly improved the mechanical properties of the UHPSCFRC, exhibiting more than 27.55% increase in compressive strength, 17.36% increase in splitting tensile strength, and 21.5% increase in flexural strength compared to the control sample. The UHPSCFRC sample with 10% NWSA demonstrated superior performance across all extreme durability tests, surpassing both the control and other modified samples. XRD analysis revealed the development of microcracking at temperatures of 450 and 600°C due to the evaporation of absorbed and capillary water and the decomposition of ettringites.

Assessment of Water Transport and Chemical Attack of Meta-Illite Calcined Clay Blended Cement in High-Performance Concrete.

Rapid urbanisation causes a rise in the need for infrastructure, which in turn fuels the creation of additional concrete and further increases cement supplies. Activation of illite-based clay mineral and usage in concrete production is one of the sustainable ways to address the cement industry anthropogenic issues. This study evaluates the durability properties of water transport (water absorption, and capillary water absorption), and resistance to aggressive environments (5% solutions of hydrochloric acid, HCl; sodium sulphate, Na2SO4; and calcium chloride, CaCl2) of meta-illite calcined clay (MCC)-based high-performance concrete (HPC). For this purpose, concrete was produced with 5, 10, 15, 20, 25 and 30% MCC content in partial substitution of CEM II. Results from the water absorption tests indicate an average percentage value of 3.57%, 3.35% and 2.52% for all the observed mixes at 28, 56 and 90 days, respectively, with MCCC-10 HPC having an average best value of 2.23% across the curing ages. On all observed days, the 5 to 15% cement replacements had very close average water sorptivity value of 0.125 ± 0.001 mm/min0.5 with the control mix (0.113 ± 0.011 mm/min0.5). The aggressive environments exposure findings of the hardened MCC-based HPC specimens of 10 to 20% recorded an approximately 15% compressive strength loss in HCl, Na2SO4 and CaCl2 solutions over the 90 days of curing. In all, the HPC mixes of 5 to 15% MCC content obtained an average durability performance factor of 89%. As a result, these findings imply that MCC can replace cement in up to 15% of HPC production.

Effect of the use of retardant chemical additive in concrete on rebar corrosion

Reinforced concrete (RC) is one of the most widely used building materials. However, RC, especially in coastal seaside or humid environments, can suffer reinforcement corrosion with the result that the reinforcement fails to perform its function over time. The effect of a retarder additive used to eliminate loss of consistency in hot, windy and humid weather on the corrosion of RC elements was investigated in this work. Four different concrete types were assessed, with 0%, 1%, 1.5% and 2% additions of the chemical additive. Along with accelerated corrosion and pressure tests, physical properties such as electrical resistivity, water absorption, porosity, unit weight and capillary water absorption were also determined. The results of this work indicate that the use of up to 2% of the setting retarder did not pose a problem in terms of the physical and mechanical properties of the concrete. However, in terms of the frequently encountered corrosion problem, the use of 1.5% is more appropriate. Many chemical additives are used for different purposes in concrete and it is suggested that, alongside physical and mechanical properties, durability characteristics should also be examined when determining the suitable ratios of these additives.

Mapping Capillary Infiltration-Induced Potential in Water-Triggered Electric Generator Using an Electrical Probe Integrated Microscope.

Power generation from water-triggered capillary action in porous structures has recently geared extensive attention, offering the potential for generating electricity from ubiquitous water evaporation. However, conclusively establishing the nature of electrical generation and charge transfer is extremely challenging arising from the complicated aqueous solid-liquid interfacial phenomenon. Here, an electric probe-integrated microscope is developed to on-line monitor the correlation between water capillary action and potential values at any desired position of an active layer. With a probe spatial resolution reaching up to fifty micrometers, the internal factors prevailing over the potential distribution across the whole wet and dry regions are comprehensively identified. Further, the self-powered sensing capabilities of this integrated system are also demonstrated, including real-time monitoring of wind speed, environmental humidity, ionic strength, and inclination angle of generators. The combination of electric potential and chemical color indicator suggests that charge generation is likely correlated with ion-selective transport in the nanoporous channel during the water infiltration process. And unipolar ions (for instance protons) should be the dominant charge-transfer species. The work reveals the fundamental principles regulating charge generation/transfer during the water-triggered electric generation process.

Characterisation of new sustainable gypsum composites with low-density polyethylene waste from single-use bags

The main objective of this research is to determine the feasibility of using Low-Density Polyethylene (LDPE) waste as secondary raw material in the production of new eco-friendly gypsum composites. For this purpose, LDPE waste in crumb form has been incorporated as a partial replacement by weight of the plaster material powder at percentages of 1%, 2% and 3%. Additionally, the gypsum binder in traditional gypsum composites has been replaced for LDPE waste in granulated form, at percentages of 2.5%, 5.0% and 7.5%. The experimental campaign has involved a detailed physical and mechanical characterisation of the gypsum compounds produced to study their potential applications in the construction sector. The results show that more efficient materials are obtained with the addition of these plastic wastes, significantly reducing bulk density and thermal conductivity coefficient compared to traditional gypsum-based materials. Additionally, a considerable reduction in capillary water absorption coefficient and open porosity has been observed. Moreover, the mechanical strengths in flexion and compression surpassed the limits established by current regulations for all the prepared mixtures. In this way, these innovative gypsum composite materials can be useful for application in the production of prefabricated elements, promoting the reincorporation of these plastic wastes, which currently present a challenge from the perspective of sustainability and circular economy.

Matrix decomposition methods for accurate water saturation prediction in Canadian oil-sands by LF-NMR T2 measurements

This article presents a novel method for quantifying water saturation in oil-sand reservoirs by employing 1D low-field nuclear magnetic resonance (LF-NMR) spin-spin relaxation and bulk density measurements as indicators of pore volume variations. One of the challenges in accurately determining the volumes of bitumen and water in oil-sands is the effective separation of their overlapping T2 signals, attributed to similar spin-spin relaxation decay times and diffusive coupling. Conventional methods require deconvolution of T2 peaks and or experimentation to determine T2 cutoff values, differentiating between bitumen and water signals, notably capillary and clay-bound water. In contrast, our approach predicts the proportion of water by utilizing matrix decomposition methods to compress the T2 relaxation distribution and extract significant components. These components subsequently train the regression model, facilitating the accurate estimation of relative water saturation percentages.The NMR dataset was obtained by benchtop LF-NMR T2 measurements from 82 oil-sand samples, with preserved bitumen and water saturations at both reservoir and ambient temperatures (6 °C and 25 °C), yielding 164 observations. We examined four matrix decomposition methods, including principal component analysis, its variation integrating a kernel function, canonical correlation analysis, and partial least squares regression. X-ray CT measurements and Dean-Stark extraction ascertained the respective sample bulk densities and fluid-solid volume proportions.The PCA model prediction statistics (RMSE = 0.86%, R2 = 0.84), indicate its application can be extended for saturation prediction from NMR and bulk density well logs. Moreover, we underscore the importance of incorporating bulk density measurements and establish the statistical and physical correlations between these measurements and NMR T2 relaxation, providing insights into the approach's efficacy and causality.

A novel slide-like cotton-based evaporator with gradient evaporation strategy for seawater resource acquirement

Solar-Driven Interfacial Evaporation (SDIE) is a promising green technology with great potential for seawater desalination. In this study, a novel slide-like cotton-based solar evaporator is designed using Carbon Nanotubes (CNTs) and Musou Black (MB) in an inclined mode, achieving a fast capillary force-induced gravity-assisted water transport. The evaporator achieved a stable desalination of the concentrated brine (10.0 wt% NaCl solution) at the evaporation rate of 1.44 kg m-2 h−1 under one simulated sunlight (1 KW m−2). Adequate water supply facilitated a superior self-cleaning property without salt aggregation at the evaporation surface and its periphery. In the 10-day long-term evaporation (3.5 wt% NaCl solution), a stable water evaporation rate (1.77 kg m-2 h−1) and a light-to-heat conversion efficiency (95.47%) were obtained without salt aggregation. The evaporation rate could even reach 1.88 kg m-2 h−1 in a closed evaporation system outdoors under the practical light. Then, the gradient evaporation strategy was applied by combination of the slide-like solar evaporator consecutively in three stages, in-between which two collection tanks for the concentrated seawater were present. As the concentrated seawater can be used to extract Li, Mg, etc., and the mineral salts of the sea can be used for nutrients, bathing products, etc., the gradient evaporation strategy has realized the simultaneous derivation of the condensed pure water, the concentrated seawater with different concentrations, and the mineral salts at the last stage as industrial raw materials. This study provides new insights into the design of high-efficiency solar evaporators that can comprehensively realize the utilization of seawater resources.

The effect of nano SiO2 on mechanical properties of underwater geopolymer mortar

This study examined the effect of nano SiO2 on the mechanical properties of underwater geopolymer mortar. The granulated blast furnace slag (GGBS) was selected as the binder in this study. The nano SiO2 was used at 0, 0.5 %, and 1 % by weight of GGBS in the mixtures. Two different casting methods were used in this study. The first casting method was to produce underwater geopolymer mortar samples using the tremie funnel method. The second method was chosen as the method of producing geopolymer mortar samples at room temperature (20 ± 2 °C). The pH test for the wash-out and the slump-flow test for the self-compacting of the underwater geopolymer mortars were carried out. Geopolymer mortar samples were cured underwater and at room temperature for 3, 7, and 28 days at 20 ± 2 °C. Then, ultrasonic pulse velocity, capillary water absorption, and compressive strength tests of the specimens were applied. The results showed that the highest compressive strength among underwater geopolymer mortar samples was obtained from underwater geopolymer mortar containing 0.5 % nano SiO2 with 85.95 MPa. Also, this study found that the underwater geopolymer mortar containing 0.5 % nano SiO2 retained 97.02 % strength of the geopolymer mortar at room temperature.

Characteristics and neutron imaging of capillary water absorption for metakaolin and steel fiber reinforced slag based-geopolymer mortars

The manufacturing of cement consumes energy and natural resources of raw materials, and emits large amounts of CO2. Geopolymers are eco-friendly building materials that have the potential to replace cement-based building materials. We used neutron radiography to report new data on water absorption and distribution in metakaolin (MK) and steel fiber reinforced slag-based mortars for the first time. Due to contradictory studies on the influence of adding steel fibers to slag-based geopolymers on compressive strength and the limited research on water permeability, workability and sorptivity, new results were presented. Alkaline-activated MK and steel fiber reinforced slag -based geopolymer mortars were prepared. The neutron radiography (NR) technique was used to investigate capillary water absorption in the mortars. The fresh and mechanical strengths of the mortars, as well as their permeability, workability and sorptivity, were determined. The compressive, flexural, and splitting tensile strengths, as well as the water permeabilities, increased, whereas the workability decreased as the steel fiber percentage in slag-based mortars increased. The results showed that the addition of steel fiber at volume fractions of 1%, 2%, and 3% increased the −7 and 28 days compressive strengths for the slag-based mortars by 44.7%, 50.7%, and 57.1% and 41.9%, 50.2%, and 55.1%, respectively. The NR results revealed that the resistance to water penetration in reinforced slag-based mortars is greater than that of MK. The addition of steel fiber introduced inhomogeneity in the matrix of the reinforced samples and created water-accumulating regions. Water proceeded regularly in the Mk samples but irregularly in the slag-based mortars. The capillary absorption factors k for Mk and slag-based mortars with steel fiber at volume fractions of 1%, 2%, and 3% were found to be 0.37 cm min−1/2, 0.2 cm min−1/2, 0.17 cm.min−−1/2, 0.19 cm min−1/2, and 0.2 cm min−1/2, respectively. According to NR, the optimal percentage of steel fibers in the slag-based mortar impeding water flow is 1%–2%. Steel fiber used at a high proportion to slag-based mortars increased sorptivity. To best fit the results at high absorption times, the second Fick's law of diffusion can be used.

An experimental study on mechanical behaviour of concrete by partial replacement of sand with brick fines

ABSTRACT Heat is one of the primary factors that causes concrete structures to deteriorate over time and enhance concrete’s structural properties. In an experimental investigation, brick fines were substituted for sand at different percentages of 5%, 10%, 15%, and 20% to test the mechanical behaviour of concrete exposed to high temperatures. At 15% replacement of brick powder, the maximal strength at standard temperatures had attained. An optimal concrete and ordinary concrete had then been exposed for 2 h at temperatures ranging from 100°C to 600°C at 100°C intervals. The quality check and strength characteristics of replacement and conventional concrete were evaluated, including weight loss, Ultrasonic Pulse Velocity (UPV), rebound hammer, and compressive, tensile, and flexural strengths at ambient and high temperatures. The quality of concrete decreased with temperature increase because of crack development and incompatible deformation between aggregate and cement paste. The strength decreased with increased temperature because of calcium silicate hydrate (CSH) breakdown and capillary water evaporation. Furthermore, a particular temperature at which cracks appear in concrete specimens exposed to high temperatures had determined using Scanning Electron Microscopy (SEM) and Energy Dispersive Spectroscopy (EDS) analyses. The brick powder performed better in enhancing the concrete’s strength characteristics after being heated.

Study on the Nonlinear Permeability Mechanism and Pore Structure Characteristics of Deep Confined Aquifers

The study of deep soil mechanics is the basis of deep shaft construction. Exploring the nonlinear permeability mechanism of deep confined aquifers in depth is the prerequisite and foundation for carrying out calculations of the hydrophobic consolidation settlement of thick alluviums and preventing and controlling deep-well-damage disasters. Against the background of shaft damage caused by hydrophobic consolidation settlement of the bottom aquifer of thick alluviums, a joint HPLTC-HPPNP (high-pressure long-term consolidation and high-pore-pressure nonlinear permeability) test was carried out on the bottom aquifer of thick alluviums based on the ETAS test system. This paper studied the evolution law of the permeability coefficient (kv) of bottom aquifers under different heads of confined water, confining pressures (σr), permeability hydraulic gradients (i) and loading–unloading methods. The internal pore structure characteristics of clayey sand were obtained by using low-field nuclear magnetic resonance (NMR) technology to explore the clayey sand’s nonlinear permeability micro-mechanism. The research results showed that the bottom aquifer seepage volume (ΔQi) under high stress is affected by the head pressure difference and pore water dissipation, and kv decreases with an increasing σr according to the power function relationship. The influence of the hydraulic gradient (i) on kv is significantly influenced by σr. When σr < 4 MPa, kv decreased with an increasing i, and when σr > 4 MPa, kv increased with an increasing i first, then decreased, before then tending to be stable. Under different stress states, the T2 spectrum of clayey sand showed a bispectrum peak type, and the adsorbed water content decreased linearly with an increasing σr, while the capillary water decreased according to the power function. The content of capillary water in the permeable pores plays a key role in the permeability of clayey sand, and it has a power function relationship with σr. The research results of this paper provide a good experimental method for the study of deep soil permeability characteristics and parameter determination, provide a theoretical basis for deep alluvial hydrophobic consolidation and settlement, and further make up for the shortcomings of existing deep soil mechanics in permeability characteristics.

Magnesium oxychloride cement with hydrophobic pore network for utilizing as oil well cement

Magnesium oxychloride cement (MOC) possesses some excellent characteristics, which can be used as oil well cement, to deal with the complex environmental conditions in oil and gas wells. However, the water resistance property of MOC is poor. In this study, a new type of magnesium oxychloride cement (MOC) with improved water resistance was developed by modifying the pore structure of pure MOC using hydrophobic admixtures. To assess the performance of the new MOC, a range of tests were performed, including compressive strength, softening coefficient, capillary water absorption, pore size distribution, mineral composition and microstructure analysis. The results showed that the pore size distribution of the MOC was altered from a large pore-dominant structure to a small pore-dominant one. The hydrophobic admixture and the gel substance formed on the strength-providing phases prevented them from water erosion, resulting in enhanced strength and water resistance. This new type of MOC has the potential to be used in challenging environments, such as oil and gas wells and underwater structures.

A quantitative theory integrating solid surface hydrophilicity and pore structure features for non-phase-change drying of sewage sludge through gradient increase of ultrahigh filtration pressure

The sustainable application of thermal sludge drying process is limited by the high energy consumption due to the phase-change latent heat of moisture. This study proposed that the ultrahigh pressure filtration could realize the non-phase-change sludge drying. The lowest water content of 28.12 wt.% was realized by the filtration pressure of 21 MPa for the excess sludge with polyaluminium chloride as the conditioning agent. With the stepwise increase of filtration pressure employed (5-21 MPa), the diameter of solid pores was gradually narrowed to the same order of magnitude with the thickness of vicinal water film (i.e., 1-10 nm). As a result, the capillary water was transformed into the vicinal water, and the solid-water interface interaction played more crucial roles in water occurrence states. However, Hagen-Poiseuille equation was introduced to estimate the pore water outflow based on the pore wall hydrophilicity and the external filtration pressure, which implied that there can be always a sufficiently large driving force to maintain the water outflow rate no matter how the pore diameter is small and the sidewall is hydrophilic. Typically, the fitting results of excess sludge (R2=0.985, p-value<0.01) indicated that the pressure gradient of 2.11 × 109 Pa/m was required to maintain the pore water flow rate of 1.38 × 10−15 m3/s with the median pore diameter of 5.33 × 10−7 m. All these findings broke through the conventional cognition that only thermal drying process can decrease the sludge water content below 60 wt.%, and facilitated energy saving of sludge dewatering process through non-phase-change separation, i.e., ultrahigh pressure filtration.

Hybrid regression models: predicting of the capillary water absorption properties of construction stones

Hybrid regression models: predicting of the capillary water absorption properties of construction stones

Durability and Mechanical Properties of Granulated Blast Furnace Slag Based Geopolymer Concrete Containing Polyolefin Fibers and Nano Silica

In the current study, the improvement of granulated blast furnace slag (GBFS) based geopolymer concrete (GPC) applying 0 – 2% polyolefin fibers (POFs) and 0 – 8% nano-silica (NS) is investigated. After curing the specimens, they are subjected to compressive strength, tensile strength, elastic modulus, Ultrasonic Pulse Velocity (UPV), and impact resistance tests to evaluate their mechanical properties and durability. Moreover, the permeability of specimens is also assessed using water absorption. The compressive strength, tensile strength, and elastic modulus of the concrete increase by up to 22%, 14%, and 24%, respectively. The addition of the POFs to the GPC significantly increases the tensile strength (by up to 9%) and the absorbed energy due to the impact. By adding NS to the GPC composition, the results of the permeability and water capillary absorption test were improved. These results are evaluated through microstructure analysis, along with ultrasonic, X-Ray diffraction (XRD), X-Ray fluorescence (XRF), and scanning electron microscope (SEM) tests.

Environmentally Friendly Masonry Mortar Blended with Fly Ash, Corn Cob Ash or Ceramic Waste Powder.

Implementing a circular approach through waste valorization in mortar production with environmentally efficient mix design is a viable pathway for relieving the ecological burden of greenhouse gas emissions, resource depletion and waste management. The main objective of this paper is to evaluate the feasibility of using fly ash (FA), corn cob ash (CCA), and ceramic waste powder (CWP) as supplementary cementitious materials (SCM) in cement-lime masonry mortars. As part of an extensive experimental study, twelve mortar mixtures were made: three reference and nine blended, with mixing ratios of 1:1:5, 1:0.7:4.2, and 1:1:4 ((cement + SCM)/lime/sand), by volume. The examined properties include workability, compressive and flexural strengths, dry bulk density, capillary water absorption, adhesive bond strength, and water vapor permeability. The compressive and flexural strengths of tested mortars were notably impaired, with reductions of up to 60%, while the capillary water absorption coefficient rose by 100% compared to the reference values. The adhesive bond strength of some blended mortars exceeded the strength of the reference mortars. Nevertheless, all blended mortars fulfilled the requirements for general-purpose mortars, while the majority met the criteria for structural masonry applications. In addition, a performance-based index and weighting triangle were used for the comparison and ranking of all analyzed mortar mixtures. The findings of this study may herald a novel use of FA, CCA, and CWP as more eco-friendly binding materials in contemporary construction leading to the reduction in the process's carbon footprint, the improvement in cost efficiency, and the mitigation of the detrimental environmental impact of waste disposal.

COOT–SVR model: estimation of the capillary water absorption of building stones

COOT–SVR model: estimation of the capillary water absorption of building stones