Water Permeability Of Concrete Research Articles

Reusing Ceramic Waste as a Fine Aggregate and Supplemental Cementitious Material in the Manufacture of Sustainable Concrete

A viable strategy for promoting sustainable development and a cleaner environment is the reuse of demolition-related ceramic waste and ceramic manufacturing byproducts in the production of concrete. The purpose of this study is to assess the possibilities for using ceramic waste in the production of concrete as a fine aggregate and cementitious material. The effectiveness of concrete mixtures incorporating 20–100% ceramic waste fine (CWF) as a replacement for natural fine aggregate and 10–30% ceramic waste powder (CWP) in place of cement was evaluated. Their influence was assessed with respect to workability, mechanical performance, durability, and elevated temperature resistance. The results were analyzed via energy dispersive x-ray (EDX) and scanning electron microscopy (SEM). The findings illustrated that the increase in the replacement levels of CWP and CWF decreases the concrete workability. The mechanical performance of concrete mixtures is enhanced under compression and flexural tests as the replacement ratios of CWF and CWP increase up to 50% and 10% as replacements of sand and cement, respectively. The increases in compressive and flexural strength were 5.33% and 8.14%, respectively, at age 28 days. The concrete water permeability significantly increases as the CWF replacement ratio increases, and the incorporation of CWP reduces this negative impact. After exposure to 200, 400, 600, and 800 °C, the residual compressive strengths of concrete mixtures incorporating CWF and CWP were up to 95.02%, 89.66%, 74.33%, and 51.34%, respectively, compared to control mixtures, which achieved 84.25%, 76.03%, 59.36%, and 35.84% of their initial strength. Microstructure analysis revealed that combining CWP and CWF significantly improves cement hydration when compared to the reference mixture. Thus, the use of CWF and CWP in the production of masonry mortar might be an economical alternative that would aid in raising the recycling rate of demolition and construction debris and supporting sustainable growth in the building sector.

Permeability study of water-proofing admixture and fly ash incorporated concrete using standard and own built test

One of the most important factors influencing concrete's age is its permeability. Many commercially available water-proofing chemicals claim to be helpful in water-proofing concrete while improving other attributes such as compressive strength, modulus of rupture, durability, and density. Furthermore, the mineral admixtures also improve concrete's mechanical and durability properties. DIN 1048 (Part 5), EN 12390 – 8, and IS 516 (Part 2): 2018 are standard codes for determining the water permeability of concrete. These codes lack information on the drying conditions of concrete samples between the pressure cycles of water permeability tests and leads to an inability to evaluate the effectiveness of using admixtures in concrete. Some more limitations of these codes are fixed duration of testing and bulky apparatus. In this study, the one- and four-cycle test with oven drying and the air-drying combination is carried out. The present study also focuses on evaluating the effectiveness of fly ash and waterproofing admixture as an additive in concrete to reduce the water permeability of concrete. Further, limitations of the previous test are taken into consideration, and the own built apparatus is developed. The own-built apparatus (water penetration test) works at the same pressure (5 kg/cm2) as the standard method. The own-built apparatus reduces the testing duration, and a more significant number of samples can be tested at a time compared to the traditional method. The results of water penetration depth for the different samples prepared at a common effective w/c ratio have given an insightful effect, as the concrete with similar strength was compared for permeability evaluation. Therefore, the present paper will enlighten the testing procedure, duration, and comparison of (0, 15, 25, and 35%) fly ash and (0.8 and 1.2%) waterproofing admixture concrete. The 15%, 25% and 35% fly ash incorporated concrete was found effective by 18 to 27% in reducing the penetration depth, whereas 0.8 and 1.2% water proofing admixture concrete reported 9 and 14% effective compared to control concrete. This study will help researchers to evaluate the comparative effectiveness of the ability of water-proofing and mineral admixtures in improving the permeability of the concrete and ultimately enhancing the durability of the concrete structure.

Porcelain Tile Polishing Residue in Concrete as an Additive or Replacement for Portland Cement

In this study, 10–50% of porcelain tile polishing residue (PPR) was used as an additive or as partial replacement of cement in concrete. The cement consumption was kept constant by correcting the amount of sand for each mixture. Concrete workability (slump) was reduced by up to 88.72% when PPR replaced the cement by up to 30%, while it was reduced by only 4.10% when PPR was added to the concrete at the same levels. Compressive strength at 28 days increased up to 92.22% with 50% PPR as additive, reducing the equivalent emission of CO2 per m³ of concrete up to 38.18%. PPR incorporation reduced the water permeability of concrete by up to 30.70% and 17.54% when used in addition and in cement replacement, respectively. Overall, PPR as an additive up to 50% and in cement with substitution levels up to 10–40% presented themselves as viable solutions for developing more resistant and durable concretes than the reference mixture (without incorporation of PPR).

Effect of CO2 surface treatment on penetrability and microstructure of cement-fly ash–slag ternary concrete

Permeability is an important indicator of the durability of cement-based materials. Surface treatments are effective in reducing permeability, and thus improving durability. In this study, CO2 surface treatment, as a new method, was investigated explore the efficiency on cement-fly ash-slag ternary concrete. The results show that the CO2 surface treatment densified surface microstructure and reduced both air and water permeability of concrete. With increase in fly ash and slag contents, the efficiency of CO2 surface treatment in reducing concrete permeability was enhanced. The results of thermogravimetric analysis (TGA), X-ray diffraction (XRD), environmental scanning electron microscopy (SEM) and energy dispersive X-ray spectroscopy (EDX) indicated that CO2 surface treatment consumed calcium hydroxide (CH) and formed calcium carbonate (CaCO3). Moreover, the calcium-to-silicon ratio (Ca/Si) of calcium silicate hydrate (C–S–H) decreased after surface treatment and CaCO3 was covered by C–S–H during further hydration.

Improvement of Bond Strength and Durability of Recycled Aggregate Concrete Incorporating High Volume Blast Furnace Slag.

This paper aims to experimentally investigate the effects of high volume cement replacement of blast furnace slag (BFS) on the bond, strength and durability of recycled aggregate concrete (RAC). Concrete mixtures were prepared containing 0%, 15%, 30%, 45%, 60% and 75% BFS with each of recycled aggregate and natural aggregate. Measurements of the compressive and bond strength, the resistance to chloride-ion penetration and the water permeability of concrete are reported. In addition, a microhardness test was also performed to evaluate the quality of interfacial transition zone (ITZ) in concrete. Test results of the bond strength and the compressive strength of RAC mixtures, in spite of the cement replacement amount with BFS, show that the concretes result in reduced strength when compared to natural aggregate concrete (NAC) mixtures, while the strength gains for the BFS-based concrete are higher than that of the reference mixtures without BFS at long-term ages. Incorporating BFS in concrete can inherently improve the durability properties by increasing higher resistance to chloride-ion penetration and lower water permeability. This improvement in the mechanical and durability properties of the BFS-based RAC mixture may be due to the additional pozzolanic reaction of BFS, which enhances the properties of ITZ in concrete, resulting in an improvement of the strength of concrete.

Effect of Recycled Concrete Aggregates on Compressive Strength and Water Permeability of Concrete

This paper discusses the effects of recycled concrete aggregates (RCA) on compressive strength and permeability of recycled aggregate concrete (RAC) by using recycled concrete aggregates as a replacement of natural coarse aggregates (NCA). Four replacement percentages were used to study the effect of replacement. Replacement percentages used were 30%, 50%, 70% and 100% with 0% replacement was used as control. Mix design of 1:1.24:2.6 was used in the study with water to cement ratio of 0.43. Influence of RCA on compressive strength was determined for all the mixes as per ASTM C39 standard. The permeability of all the mixes was determined by measuring absorption, sorptivity and Darcy’s coefficient. Results of compressive strength indicated that concrete with 30% replacement of NCA can be successfully used in structural concrete without compromising too much on strength. Whereas, the replacement of natural aggregates with RCA has a negative impact on the permeability of concrete at all replacement levels. Absorption, sorptivity and permeability of natural aggregate concrete is lower as compared to RAC with 30% replacement showing the better performance as compared to other replacement ratios.

An Experimental Assessment of the Water Permeability of Concrete with a Superplasticizer and Admixtures.

This study presents a flow pump technique usually used for evaluating the permeability of soils, which was, for first time, applied to measure the water permeability of concrete. Additionally, a new easy-to-apply method to determine permeability is proposed, based on a modification of Valenta’s formula. In the calculations, the apparent air content of concrete mixes was taken into account. An additional purpose of the conducted research was to determine the influence of a new generation of polycarboxylate superplasticizer and chemically active admixtures on the permeability, compressive strength, and other properties of concrete. The following four types of concrete were tested: concrete without admixtures, concrete with an admixture to increase the compressive strength, concrete with a superplasticizer, and concrete containing two admixtures simultaneously. The results showed that the proposed method allows to obtain reliable measurements within a very short period of time. The obtained results confirmed that new method may be very useful in engineering practice, particularly in terms of the watertightness of hydrotechnical concretes and the properties of the concretes used in bridge construction, underground parts of office buildings, or sealed tanks.

A meso-scale model toward concrete water permeability regarding aggregate permeability

The permeability of natural aggregate is close to cement mortar with relative lower w/c ratios, therefore when calculating the overall concrete water permeability, the effect of aggregate permeability cannot be neglected. This paper presents a sophisticated 3D three phase meso-scale model based on an efficient method of generating random ellipsoidal particles within confined cylindrical space. The meso-scale model considers concrete as the combination of mortar, aggregate and interfacial transition zone, and is used to characterize the permeability of concrete. Furthermore, a series of permeation experiments of concrete with different w/c ratios and aggregate volume fractions are conducted to exemplify the effects of aggregates on concrete water permeability and provide parameters and verification for numerical models. The effects of aggregate permeability on concrete water permeability is evaluated based on both experimental and numerical results. And the permeability coefficient of aggregate adopted in the experiment is estimated reasonably and incorporated into further numerical predictions of concrete water permeability. By comparing the experimental and numerical results, the applicability of meso-scale model proposed here is validated and the effects of aggregate on water permeability of concrete with different w/c ratios vary from each other, depending on the ratio of water permeability of aggregate and mortar.

Cylindrical Chamber: A New In Situ Method for Measuring Permeability of Concrete with and without Admixtures

Abstract Because the permeation of water through concrete causes both physical and chemical deterioration, the durability of concrete structures is mainly dependent on the concrete permeability. According to the literature surveyed by the authors, the only reliable test that measures the water permeability of concrete is the laboratory standard test of BS EN 12390-8, Testing Hardened Concrete. Depth of Penetration of Water under Pressure. Therefore, having realized the need for an in situ method for measuring the water permeability of concrete, this article introduces the newly developed method of “cylindrical chamber,” which is proposed and developed by M Naderi. In order to be able to prove the acceptability of this new method, a total of 102 concrete cubes with dimensions of 150 mm and different compressive strengths and mixtures were prepared, and their water permeability were measured using both the laboratory standard test of BS EN 12390-8 and the cylindrical chamber method. The concrete mixtures employed contained 5, 10, 15, and 20 % of silica fume, plus fly ash, zeolite, and limestone powder. The results obtained tend to show a very good agreement between the corresponding water penetration depths associated with the two methods. In this regard, a linear relationship is seen to exist between the two comparative sets of results with a determination coefficient of 0.9489. It is also seen that the addition of the previously mentioned admixtures decreases the water permeability of the concrete when compared with the permeability of concrete containing portland cement alone. The optimum replacement level of zeolite and limestone powder was also found to be around 10 %. Meanwhile, no optimum content was seen for silica fume and fly ash.

Impact of Chemically Treated Waste Rubber Tire Aggregates on Mechanical, Durability and Thermal Properties of Concrete

Studies have shown that the incorporation of waste tire rubber aggregates reduces the strength, increases permeability and decrease thermal conductivity of concrete. However, only a few studies have investigated the effect of surface-modified rubber aggregates on the properties of concrete. This study investigates the effect of the surface treatment of waste tire rubber as coarse aggregates with different oxidizing solutions and different treatment durations on the mechanical, durability and thermal properties of concrete. The properties of concrete incorporated with 8% rubber coarse aggregates (by volume of natural aggregates) which were treated with three different solutions: water (H2O), 20% sodium hydroxide (NaOH) and 5% calcium hypochlorite [Ca(ClO)2] (both as% weight of water) for durations of 2, 24, and 72 h, respectively. The effect of these treatments on the compressive strength, splitting tensile strength, water permeability, thermal conductivity and diffusivity of concrete was investigated. Results show that Ca(ClO)2 has a more positive effect on the strength and permeability compared to NaOH solution and water. Experimental results were statistically analyzed using ANOVA and Post Hoc tests. The analyses showed that the improvement of concrete strength is only significant when the treatment with NaOH and Ca(ClO)2 is prolonged to 72 h. Furthermore, the microstructural analysis of concrete showed that the improvement in the strength is due to the improved bonding between cement paste and rubber aggregates as a result of surface treatment. This microstructural improvement also resulted in lower water permeability of concrete. However, the thermal conductivity and diffusivity increased when the surface treatment duration increases as there are less air voids in the samples. This study shows that, with appropriate pretreatment, a certain percentage of natural aggregates can be safely replaced with waste tire rubber aggregates while maintaining sufficient quality of the resulting concrete.

Effects of active waste powder obtained from C&D waste on the microproperties and water permeability of concrete

Using waste powder (WP) derived from construction and demolition (C&D) waste as supplementary cementitious materials in the preparation of waste powder concrete (WPC) provides a new way of reclaiming C&D waste. This paper focuses on investigating the microproperties and the water permeability of the WPC. A series of micro experiments and water permeability related tests were conducted. The results show that the elements and compound compositions of WP are similar with those of cement and fly ash. The addition of high fineness WP promotes the hydration rate and improves the pore structure of WPC due to its microaggregate filling effect. The incorporation of WP decreased the workability and drying shrinkage behavior of WPC, and the WPC with up to 30%WP has a satisfied compressive strength. The water permeability of the WPC, under capillary absorption and pressure, is lower than that of the control group, and the WPC with approximately 30%WP has the lowest water permeability. Subjected to the harsh environment of freeze-thaw cycles and applied loading, the addition of WP increases the sensitivity of the WPC to the imposed damage and water permeability. Although the imposed damage increases the water permeability of the WPC, incorporating appropriate content of WP leads to a lower water permeability of WPC than that of the control group when the exposure condition is the same.

Effect of Mill-Rejected Granular Cement Grains on Healing Concrete Cracks.

The effect of mill-rejected granular cement (MRGC) on enabling concrete to autogenously heal its cracks was investigated. The crack-healing efficiency of concrete containing 5%, 10%, 15%, and 20% wt. of MRGC as a replacement for natural fine aggregate was investigated at the age of 28 days. Concrete specimens were induced with artificial cracks and placed in water or air at 20 ± 2 °C to cure and heal the cracks for an additional 28 days. Compressive, flexural, and tensile strengths and water permeability tests were carried out to evaluate crack-healing by evaluating the strength to regain and the reduction in water permeability of concrete. For the air-cured specimens, the gain in compressive strength was between 45% and 79%, the flexural strength was between 74% and 87%, and the tensile strength was between 75% and 84% of the reference specimens for the MRGC content was between 0% and 20%, respectively. For the water-cured specimens, the gain in compressive strength was between 54% and 92%, the flexural strength was between 76% and 94%, the tensile strength was between 83% and 96% of the reference specimens for the MRGC content between 0% and 20%. The water permeability coefficients of the concrete specimens cured in water after cracking decreased by one order of magnitude, while those of the specimens cured in the air increased by the same order of magnitude. The crack-healing efficiency of concrete could be enhanced by increasing the MRGC content of concrete and hydration water.

The influence of steel fiber on water permeability of concrete under sustained compressive load

In order to investigate the influence of steel fibers on the water permeability of concrete at serviceability stage, a self-designed device was adopted and the permeability test was conducted on hollow cylindrical specimens under a sustained compressive load. The combined effect of steel fiber and compressive load on water permeability of concrete was analyzed. Ultrasonic pulse velocity was also measured to verify the damage of the concrete caused by the compressive load. The results demonstrated that the water permeability of the concrete was affected by the compressive load, a significant increment in the permeability coefficient occurred when the applied load exceeded the threshold value. The addition of steel fiber demonstrated positive effects on permeability of concrete under compressive load. The threshold value corresponding to permeability properties of the concrete under compressive load was improved with the increasing of fiber content. The ultrasonic pulse velocity of the concrete under compressive load was also influenced by addition of steel fiber. The variation of the ultrasonic pulse velocity has a certain similarity with the variation of the permeability coefficient of the specimen under compressive load. Ultrasonic pulse velocity test may be an efficient method to evaluate the permeability of concrete at service load.

Relating water permeability to electrical resistivity and chloride penetrability of concrete containing different supplementary cementitious materials

Electrical test methods for predicting concrete penetrability have been widely accepted for use in assessing quality and durability of concrete; however, these methods are indirect and have not been related to concrete water permeability. This research compares three standardized electrical test methods, AASHTO T 358, AASHTO TP 119, and ASTM C1202, to hydraulic/water permeability. As no consensus standardized water permeability test method is available, a uniaxial, steady-flow permeameter test that has generally been used within the research community was employed for this research. The results demonstrate that the electrical test methods investigated for predicting concrete penetrability are not necessarily appropriate for concrete mixtures containing alternative supplementary cementitious materials. Materials with electrically conductive components in pore solution or bulk matrix perform poorly in electrical testing such as surface or bulk resistivity, or chloride ion penetrability testing, although water permeability indicates comparable performance to traditional supplementary cementitious materials.

Influence of cellulose fiber addition on self-healing and water permeability of concrete

Crack formation under tensile forces is a major weakness of concrete. Cracks make concrete vulnerable to extreme environment due to ingress of water and harmful compounds from surrounding environment. Even though concrete is susceptible to cracking it has ability to seal its cracks by itself to some extent due to autogenous self-healing. So far only few studies have been done on autogenous healing of fiber reinforced concrete. So, this study aims to evaluate the self-healing potential and water permeability of cellulose fiber reinforced concrete (CeFRC). The two types of composites; control and cellulose fiber reinforced concrete have been investigated. Compressive strength and flexural tests were performed to measure the mechanical properties of the composites, water permeability test was used to evaluate the coefficient of permeability and the self-healing performance was investigated by using ultrasonic pulse velocity (UPV) and a patented self-healing test. The results indicate that the water permeability coefficient decreased by 42 % whereas the healing ratio increased at a higher rate for the initial days of healing when cellulose fibers were added in the mix. CeFRC also results in a 7.8 % increase in the flexural strength and demonstrate a higher self-healing ratio based on the UPV test.

Macro polypropylene fiber influences on crack geometry and water permeability of concrete

In order to study the effect of macro polypropylene fiber on crack geometry (tortuosity, surface roughness) and water permeability of concrete, the independently designed laser scanner was adopted to obtain the surface coordinates of the crack, the coefficients of crack tortuosity and surface roughness were introduced and the crack tortuosity and surface roughness were evaluated quantitatively through the MATLAB programming, the crack geometry of the specimens reinforced with macro polypropylene fibers and specimens without any reinforcement were compared. A self-designed device was adopted to the water permeability test, the influence of macro polypropylene fibers on water permeability of cracked concrete was studied. The Poiseuille law was modified regarding to the tortuosity factor and surface roughness factor. The results showed that: the coefficients of variation of the tortuosity factor and surface roughness factor were relatively small for all kinds of samples and could be used to verify the crack geometry of concrete. The crack geometry of the concrete was affected by the macro polypropylene fiber and the tortuosity and surface roughness of the crack increased with the increasing of fiber dosage. The modified Poiseuille law could be adopted to predict the water permeability of the cracked concrete.

Experimental Study on Water Permeability of Rubber Aggregate Concrete

In this paper, the water penetration resistance of rubber aggregate concrete is studied by using the water penetration height method. The experiment results show that: Under the condition of the same dosage, the greater the fineness module, the better the impermeability. Under the condition of the same particle size, the higher the dosage, the better the impermeability. Moreover, the strength of rubber aggregate concrete cannot determine its impermeability. The impermeability of rubber aggregate concrete is analyzed by binary regression analysis. The results show that: Rubber aggregate content and fineness module have obvious influence on the water permeability of concrete. The established permeability regression equation can estimate the permeability height of rubber aggregate concrete, which has certain guiding significance for practical engineering.

Effectiveness of two field methods of saturating near surface concrete on the water permeability of in situ concrete

Determining the water permeability of concrete in structures remains a challenge because of difficulties in removing the influence of its moisture content. Saturating concrete with water could be one option, but this is not easy to achieve on site. This paper reports a testing programme carried out to assess the reliability and effectiveness of two field saturation methods, viz. vacuum saturation and ponding. The water permeability test results after applying the vacuum saturation and ponding were compared with that obtained after incremental immersion. It was found that ponding was unable to remove the influence of moisture, whilst vacuum saturation was effective for wet concretes. The results obtained from the electrical resistance measurements after incremental immersion suggested that the water permeability of concretes can be accurately determined by carrying out in situ permeability tests if the near surface region up to a depth of 25 mm is fully saturated.

Modeling the effects of microcracks on water permeability of concrete using 3D discrete crack network

In order to better understand the transport mechanism associated with the microstructural heterogeneity of cracked concrete composite, a modeling scheme is proposed and employed to assess the effects of microcracks on water permeability of concrete. Numerical samples containing 3D discrete crack network (unpercolated and percolated) with different geometric parameters (including crack density, width, length and roughness) are generated to represent the cracked concrete composite, and the effective permeability is estimated using finite element method (FEM). Extensive numerical simulations for more than 8600 concrete samples are carried out to extract the effects of microcracks on the water permeability. The results indicate that crack percolation is a determinant factor for increasing the transport properties of concrete. In addition, for concrete composite with unpercolated crack network, the influential factors to water permeability are crack density and length, while the effect from crack width is negligibly small; and for the percolated case, crack density, width and roughness are more closely correlated with the permeability of cracked composite.

Electrical Indication of Modified Concrete´s and Mortar´s Ability Resist Chloride Ion Penetration

This article describes the ability of concrete and mortar mixtures with different fly ash contents to resist chloride ion penetration 14 and 28 days after casting. The Rapid Chloride Permeability Test (RCPT) in accordance to the norm ASTM C1202 was used in order to obtain qualitative indications of the chloride ion penetrability depending on the electrical conductance of concrete respectively mortar samples. Furthermore, the Automatic Concrete Water Permeability Apparatus at Four Cells C430X from Matest was used to measure the water permeability 28 days after casting. Finally, the uniaxial compressive strength was measured 28 days after casting. The following conclusions can be made. The results of the Chloride Permeability Test (RCPT) did not show a clear correlation between the ash content, the a/c ratio and the Chloride Ion Penetrability. However, the chloride diffusion coefficient for the hormone and mortar at 28 days tends to increase with increasing a / c ratio and decreases with the age of hydration. As for permeability, an increase in the permeability was found at 28 days of age with an increasing ratio of a/c ratio.