Porous Concrete Mixtures Research Articles

A machine-learning based approach to estimate acoustic macroscopic parameters of porous concrete

Porous concrete with expanded clay inherent porosity makes it an interesting and effective acoustic material, applied in numerous scenarios such as highways, airports and architectural structures, due to its capacity to mitigate noise pollution, by absorbing and damping sound waves. It is usually accepted that macroscopic properties such as open porosity, tortuosity or airflow resistivity of such materials play a fundamental role in the definition of the internal absorption process. This study explores the application of tailored artificial neural networks (ANNs) for predicting first the macroscopic properties (open porosity, tortuosity and airflow resistivity) and then the sound absorption coefficient (α) of these porous concrete mixtures, using only two input parameters (size class of the expanded clay and density of the test specimens). The results demonstrate the efficacy of the proposed ANN approach in accurately predicting macroscopic properties and the sound absorption coefficient of these mixtures, making it possible to obtain such important parameters in an effective and much simpler way.

The effect of adsorbent-containing nanoparticles on the efficiency of porous concrete

For the past decade, porous concrete has been applied to surface pavements and sidewalks to control urban runoff. The effects of including mineral adsorbents and nanoparticles in porous concrete for improving structural properties were investigated in this study. The porous concrete mixture had two levels of nanoparticles (2 and 5 % w/w) as well as zeolite, travertine, scoria, and pumice in amounts of 5, 10, and 15 %. The permeability, compressive strength, and porosity of porous concrete samples were measured. According to the findings, adding nanoparticles to porous concrete increased the compressive strength but reduced the permeability and porosity. On the other hand, samples without nanoparticles did not show a consistent trend. The incorporation of additives up to a particular limit decreased the compressive strength and then increased it as the pores filled. The applied additives performed almost identically regarding the compressive strength; however, the samples containing pumice and zeolite performed better in terms of permeability and porosity. The results also revealed that employing nanoparticles in conjunction with adsorbents increased the physical characteristics of porous concrete, with 5 % nanoparticles that increased the compressive strength by 84 % in the control sample. Furthermore, this sample's permeability and porosity were reduced by 50 % and 13 %, respectively. The sample containing 15 % travertine and 5 % nanoparticles had the most significant effect on the compressive strength with a 122 % improvement. Furthermore, by increasing the concentration of nanoparticles in the concrete, its compressive strength also increased. However, the inclusion of nanoparticles reduced permeability and porosity, so that the sample containing 15 % pumice and 5 % nanoparticles exhibited the highest change, with a 44 % reduction compared to the sample without adsorbent and nanoparticles.

Optimal Constituent Mix Ratio for Improved Fresh Properties of Cementitious and Alkali-Activated Porous Concretes

This study focuses on the ideal mix of constituents (aggregate, binder, liquid phase, and admixtures) for porous concrete (PC) with optimal fresh properties to be used in pervious road pavements. Ordinary portland cement (CEM-I) and alkali-activated blast furnace slag (AA-BFS) were used as binders. This experimental investigation focused on finding the mix proportion that can best produce a consistent fresh mixture in which the mortar attaches strongly to the coarse aggregates. CEM-I and AA-BFS mortars and concretes were designed to meet the consistency criteria for PC mixtures and then tested to assess their volumetric and mechanical properties. The effect of mix composition on the consistency of fresh mixtures was adjudged through statistical analyses. In the case of AA-BFS mixtures, latex admixture (LA) and a polycarboxylate-ether-based superplasticizer (SP) both helped to achieve a higher level of consistency, and the addition of a viscosity-modifying admixture was necessary for CEM-I PC mixtures only. In terms of hardened properties, AA-BFS mortars exhibited slightly higher strengths than CEM-I ones independently of curing time. Although neither LA nor SP increased strength values at the mortar scale, in PC mixtures, the use of LA proved fundamental in the production of AA-BFS concrete with adequate strength values. This study recognizes that the optimization method as per the consistency assessment of fresh mixtures can be applied to PC with both cementitious and AA-BFS binders.

The Effect of Variations of Fly Ash Filling Materials on Porous Concrete Using Local Aggregates from South Borneo

South Kalimantan has local aggregates that can be used as porous concrete making materials, which is one of the innovations in the infrastructure of environmentally friendly road pavement that serves to drain surface water into the ground. Porous concrete produces a lot of empty space as an air cavity that is 15%-25% of its total volume and also has a slump value that is close to zero. This study uses fly ash filler material as one of the efforts to reduce cement in porous concrete making materials. This research aims to find out the characteristics of the material, the composition of variations of porous concrete mixture, compressive strength and porosity of porous concrete. Testing uses the SNI method which consists of testing cement, fly ash, coarse aggregates and concrete. Concrete testing is done, namely the compressive strenght and porosity of concrete. Based on theresults of research characteristics of cement and fly ash materials have met the specifications of SNI and the results of rough aggregate testing have met the specifications. In porous concrete the fly ash variation of EM0% is obtained the compressive strength is 20.37 MPa and its porosity is 2.34%; in porous concrete the variation of fly ash EM15% obtained the compressive strength of 21.44 MPa and porosity 2.07%, and porous concrete variation fly ash EM30% obtained the compressive strength of 6.05 MPa and porosity by 6.80%. From the results of the analysis, it is found that there is an inverse relationship between compressive strength and porosity. More higher the porosity of the porous concrete, more lower the compressive strength. This happens because the void ratio affects the compressive strength of porous concrete, more greater the void value making higher the porosity value and causes the compressive strength to decrease.

Pengaruh Penambahan Serat Polypropylene terhadap Kuat Tekan dan Nilai Permeabilitas pada Beton Berpori

The infrastructure growth has an impact on reducing green areas, which will be followed by reduced water catchment areas. Porous concrete is one of the porous materials that can be used on a pedestrian walk, which is able to drain water. The porous concrete has a limitation strength. This research aims to determine the effect of using various content of chemical additive and polypropylene fibers for porous concrete mixtures related to the compressive strength and permeability values. This experimental method referring to ACI 522R-10 Standard. That specimens using chemical additives and variations of polypropylene fibers: 0.05%, 0.1%, 0.15%, 0.2%, and 0.25% by weight of cement. The results showed that the specimen which had the highest compressive strength was 16.9 MPa, which was added 0.25% polypropylene fiber. The addition of polypropylene fibers increases the compressive strength value by 5.6%. Based on the compressive strength and permeability graphs, it can be estimated that the optimal content of polypropylene fiber is 0.17% by weight of cement.

Mechanical strength and hydraulic properties of modified porous concrete mixtures

This study presents a comprehensive experimental investigation on the behavior of porous concrete mixtures intended to be used as surface road layer containing mineral admixture. Silica fume and/or fly ash were used to formulate modified concrete mixes at ratios ranged from 10% to 20%. A systematic change in 50% of the 9.5 mm aggregate particles size was adopted throughout single size coarse aggregate of 5mm. This in turn produces two groups of concrete mixes and eight individual mixtures. The compressive and tensile strengths, voids content and permeability characteristics were measured and the obtained results were compared with relevant guide of porous concrete. The results showed that a moderate strength of 24 MPa can be obtained at early ages. For the same concrete mixture, the values of voids content and permeability were 21.7% and 19.3 mm/s, respectively. Such kind of concrete can be used in construction of roads and it helps in water draining purposes.

Effective microorganisms composite scupper drain (EM-CSD) as a new revolution in drainage system: A preliminary study

Effective microorganisms composite scupper drain (EM-CSD) system, which is designed using eco-composite in porous concrete with the concrete mixture and a cement replacement, consists of the waste material elements that being recycled, such as wood waste ash, egg shells, rice husk ash (RHA), and many more, for the purpose of managing stormwater quantity and quality, and also for ecologically sustainable development. The numerous ecocomposite materials researches have been conducted, specifically for the building materials. In addition, several impermeable surfaces including sidewalks, secondary roads, and also parking lots in several countries have used the porous concrete materials, as it is good quality in terms of the concrete strength, the porosity, the workability, and also the maintenance cost reduction. Besides, previous researches related to effective microorganisms (EM) as an admixture in concrete have been done, as a part of construction materials. However, the previous researches of eco-composite, specifically using RHA and EM did not focus on the drainage systems. Therefore, this paper presents a preliminary study of EM-CSD system using RHA and EM as a cement replacement, as a green technology and sustainable development in urban drainage systems. This kind of technology is a new revolution to replace the existing drainage systems, with high cost effective consideration, high concrete mixture strength and workability, and low temperature. For the part of the research, Shah Alam, Selangor as the main study area to implement this kind of the new drainage system technology for the purpose to reduce the flash flood phenomenon, to overcome the dengue fever issues due to stagnant water in the drainage system, and also vandalism of the drainage cover, which cause a safety issue for public. This preliminary study using EM-CSD as a new revolution in the drainage system indicates the ecocomposite porous concrete mixtures are expected able to overcome the drainage system problems with low cost maintenance and high on concrete strength and workability.

Laboratorial investigation on sound absorption property of porous concrete with different mixtures

Porous concrete (PC) is considered as an environmentally friendly pavement material due to its internal porosity. It has good functions such as: mitigate stormwater runoff, removal water pollutants, noise reduction, and mitigate urban heat island benefits. Many parameters have an effect on the sound reduction of PC, especially the porosity was often considered as the main factor affecting the sound absorption ability of PC. Therefore, thirty-six groups of porous concrete were selected to obtain different porosities of PC samples in this study. These groups include twelve kinds of aggregate gradation and three kinds of cement to aggregate (C/A) ratios. The selected concrete materials are mixed and cast on different thicknesses to study the influence of different mixtures on the sound absorption ability of PC using impedance tubes method with varied sound frequency (200 ~ 2000 Hz). In addition, the correlation between the sound absorption ability and the porosity of mixtures was investigated. The results show that the porosity, aggregate gradation, C/A ratio and pavement thickness have significant effects on the sound absorption performance for the examined PC mixtures.

Treatment of domestic wastewater using the combination of porous concrete and phytoremediation for irrigation

Phytoremediation method, in combination with porous concrete and some additives, has been examined in order to reduce the contamination of unconventional water resources. This treatment system is economically cost-effective and easy to apply, compared to other treatment methods. The current study was focused on evaluating the effects of arrangement of vetiver grass and porous concrete specimens (four types of grass-specimens arrangements), vetiver grass layout on polystyrene sheets (5 × 5 and 10 × 10 cm spacing), porous concrete mixture (basic design as control, basic design + 5% zeolite, basic design + 10% zeolite, basic design + 5% pumice), temperature of the test room (10 ± 2, 20 ± 2 and 30 ± 2 °C), type of the unconventional water (domestic wastewater effluent and urban runoff) and Portland cement type (2 and 5) on the reduction of biochemical oxygen demand (BOD), chemical oxygen demand (COD), total suspended solids (TSS), and fecal coliforms. Taguchi method (robust design) and Qualitek-4 software were used to optimize the combination of aforementioned factors. Results indicated that temperature was the most effective parameter on reducing the BOD, COD, and fecal coliforms. The vetiver grass layout on the polystyrene sheets and porous concrete mixture design were more effective than vetiver grass-porous concrete arrangement. Effect of vetiver grass roots was significant in reducing the TSS content. The cement type had minimum impact on reducing the qualitative parameters of the wastewater samples. Based on the results, combination of 10 × 10 cm spacing of vetiver grass on polystyrene sheets, third type of vetiver grass-porous concrete arrangement, porous concrete mixture with 10% zeolite, Portland cement Type 2, and room temperature of 30 ± 2 °C was the best for improving the quality of wastewater effluent as compared to urban runoff. The treated effluents can be used with caution for urban green spaces or irrigation purposes, and the difficulties of the proposed combined system should be taken into consideration.

Evaluating the Effect of Porous Concrete Pavement Characteristics on Beneath Pavement Layers

The significance of the porous concrete pavement arises from the fact that it has the dual function of supporting traffic and stormwater management, in addition to many other characteristics such as minimizing noise and minimizing reflected heat. The goal of this study is to reveal more understanding of the stress-strain ratio of the porous concrete pavement and the layers beneath it. This process was done through two stages namely: laboratory stage by characterizing porous concrete mixtures (normal, and others sustainable mixtures comprised Reed Fly Ash and/or Silica Fume), and simulation stage by using a simulation program (ABAQUS) to identify the stress-strain induce an according traffic load within pavement layers. However, within the scope and materials used, the obtained results showed that the stresses within pavement layer are highly related to upper layer thickness, material types, and stiffness. Also, the main conclusion is demonstrated where there is optimum thickness (20 cm) of the porous concrete layer, which induces the minimum stress-strain in various layers of the pavement system.

Municipal Wastewater pretreatment using porous concrete containing fine-grained mineral adsorbents

Municipal and industrial wastewaters are serious threats for surface water and groundwater resources, and this threat can be converted to an opportunity by enhancing their quality, which then can be used for agricultural and landscape purposes. In the present study, the performance of porous concrete (PC) containing mineral adsorbents was investigated to improve the municipal wastewater quality. Firstly, the performance of adding fine grains (2.36–4.75 mm) in different portions (0, 10, and 20 % w/w of coarse aggregates) as well as mineral adsorbents (0.6–1.2 mm), namely zeolite, pumice, perlite, and LECA, in different portions (0, 5, 10 and 15 % w/w of coarse aggregates) on compressive strength, porosity and permeability coefficient of porous concrete was pursued. After evaluating these parameters, three samples from each percentage of fine-grains that had the highest compressive strength were selected for wastewater qualitative tests due to the fact that there was no significant difference between the other two factors. The experimental setup was next to the wastewater treatment plant of Semnan University, Semnan, Iran, which included a 200-L barrel and six canals to perform the quality tests. Six 100 × 100 × 100 mm PC specimens were positioned in each canal, in a zigzag pattern, to slow down the wastewater flow through the specimens. Inlet discharge for each canal was fixed at 0.5 L/min and total test time was 31.2 h. Qualitative parameters such as total suspended solids (TSS), chemical oxygen demand (COD), biochemical oxygen demand (BOD), and turbidity were measured before and after running the experiment. Results revealed that adding fine grains and the adsorbents increased the compressive strength, while they reduced the permeability coefficient and porosity. Also, the specimens containing zeolite and pumice had the highest compressive strength and permeability coefficient, respectively. Furthermore, mineral adsorbents reduced average concentration of TSS, BOD and COD by 40 %, 48 % and 30.5 %, respectively. The only factor that affected average turbidity level (49 NTU) was porosity, and not the mineral adsorbents. Finally, zeolite had the highest physical characteristics as well as high pollutant-reduction potential. However, it is recommended to perform further tests on different porous concrete mixtures and other adsorbents.

Multi-criteria optimum mixture design of porous concrete pavement surface layers

ABSTRACT Research has been done to obtain a Porous Concrete (PC) mixture capable of bearing heavy traffic loads while maintaining sufficient air voids (AV) to percolate water into the ground. This research aims to establish several design parameters in PC mixture dosage in order to generate a multi-criteria methodology that helps to obtain a final product, which is beneficial for both citizens and environment. Compression strength, indirect tensile strength, permeability, skid resistance, and stiffness modulus were evaluated, employing different aggregate gradations (AG), water to cement (w/c) and sand to cement (s/c) ratios, designing with the Porous Concrete that the right addition of sand and AG can improve mechanical capacity Design (PCD) methodology. Results demonstrated by around 10% and permeability rates by around 25%. This investigation provides a starting point for the use of additives in PC mixtures that helps to bring multifunctional properties such as heat island mitigation, air purification (photo-catalysis) and noise reduction, among others.

Physical and Mechanical Characterization of Sustainable and Innovative Porous Concrete for Urban Pavements Containing Metakaolin

Alternative materials to replace cement in pavements have recently been widely studied with the purpose of decreasing the environmental impacts that the construction industry generates. In this context, the implementation of sustainable urban drainage systems has grown, especially with porous pavements, with the intention to reduce water and environmental impacts. In the present investigation, the addition of alternative materials to minimize the use of cement in porous concrete pavements is evaluated. Starting from a partial substitution of Portland cement with metakaolin, experimental geopolymer concretes were produced with metakaolin and waste basalt powder according to several dosages. Two sets of mixtures were analyzed to evaluate the Porous Concrete Design (PCD) methodology for porous concrete mixtures with alternative materials. A deep analysis was proposed for the evaluation of the mechanical and volumetric properties of the mixtures. Results demonstrated that replacing 5% of cement with metakaolin can increase both permeability and indirect tensile strength. Geopolymer mixtures can achieve permeability significantly higher than the traditional porous concrete, but this decreases their indirect tensile strength. However, considering the promising results, an adjustment in the mix design of the geopolymer mixtures could increase their mechanical properties without negatively affecting the porosity, making these materials a suitable alternative to traditional porous cement concrete, and a solution to be used in urban pavements.

Design of a porous concrete mixture for drainage coverslab in pedestrian walkways

A novel design of a drainage coverslab in pedestrian walking areas has been developed as a composite section of reinforced concrete and a porous concrete layer. Porous concrete exhibits a reduction in permeability due to clogging by particulates, which severely limits the functional level of the coverslab. Slabs were tested for sever clogging mechanism in the laboratory. Samples of new coverslabs with various sizes of aggregates were cast using various compaction methods. Strength was tested using 3 point load test and clogging potential of cover slab was determined by infiltration test (ASTM C1701). Infiltration was tested on a series of coverslab samples which were clogged with top soil mixture collected from the field, landscape fine compost and silt clay slurry to simulate worse case clogging in the field. Comparison of surface textures of the porous surface was made based on sand patch test and proposed clay patch test. This paper focuses on discussing the design of porous concrete layer of coverslab, construction methods and practical issues related to application and mitigation techniques.

Proposal of a New Porous Concrete Dosage Methodology for Pavements.

Although porous concrete pavement design methods are mainly focused on maintaining high permeability rates in order to improve their ability to manage stormwater runoff, the mixture strength is paramount for its durability and service life. This paper proposes a new mixture design method for porous concrete, named PCD (porous concrete design), derived from the ACI 522R-10 and ACI 211.3R-02 standards. The aim is to improve mechanical strength in porous concrete mixtures, while ensuring enough permeability for its use in urban roads. With PCD methodology it is possible to obtain mechanical strengths 30% higher than those produced with ACI methodologies, while maintaining permeability rates close to 2 cm/s, lower than those obtained with ACI methods but still enough to manage extreme storm events. Finally, with the analytical Hierarchy Process (AHP) multi-criteria decision-making methodology and also bearing in mind safety variables, the best porous concrete mixtures are the ones produced with PCD methodology.

Porous concrete basic property criteria as rigid pavement base layer adjusting field gradation

Porous concrete has been widely used for many purposes in this couple of days. In reality, it might be difficult to create an ideal uniform graded porous concrete mixture proportion with the field gradation circumstances. The aim of this study was to find a porous concrete mix-design proportion that could adjust field gradation and meet Specifications requirements by utilizing continuous graded aggregate. Compressive strength and vertical permeability produced by porous concrete using continuous graded aggregate stayed above the minimum limit for base layer required by Specifications. Continuous graded porous concrete from mix-design variation II produced higher compressive strength, but lower void content and vertical permeability compared to mix design variation I at the age of 28-days. It was found that continuous graded porous concrete from both mix-design variations had an optimum basic parameters in specific value as well. Porous concrete that adjust the field gradation gave a better basic property criteria compared to ideal gradation. The relationship between void content and vertical permeability from continuous graded porous concrete had a similar behavior with uniform graded porous concrete. Overall, the use of continuous graded porous concrete would be very helpful in Indonesia because it can adjust the gradation on the field.

Porous concrete basic property criteria as rigid pavement base layer in indonesia

Base layer with grained material tend to occur in saturated condition at the moment of rainfall or after rainfall. In that condition, the present of traffic might also create movement below the foundation layer and reduce its bearing capacity. Nevertheless, the foundation material that contain large fine creates base layer with low permeability and slow water movement. This paper presented the procedure and result of laboratory experimental study to obtain basic property criteria for rigid pavement base layer.The porous concrete mixture was successfully designed and surpassed the minimum requirements required by Directorate General of Highways [11] [12]. It was found that there was very strong correlation between void content and permeability which created fine likelihood to use void content to represent porous concrete permeability behavior. High void content with good connection resulting weaker aggregate interlocking inside the mixture so that permeability rose whereas compressive strength fell. Solid fresh density and more filled by cement paste created a smaller void that would reduce permeability and improve compressive strength. Strong correlation between fresh density towards void content and permeability opened potency to use the fresh density as a reference to set the desired porous concrete void content on the field.

Characteristics of Pervious Concrete with Environmental Friendly Based Binder

In general, the use of massive flexible and rigid pavement for road construction causing green land reduction that have an impact on the reduction of the catchment area. Therefore, the use of porous concrete is an environmentally friendly alternative. Its usage is expected to absorb water into the ground. Permeable pavements have different design goals if compared to the conventional pavement, due to the ability to infiltrate the storm water through the pavement surface. The purpose of this research is to get the optimum proportion of porous concrete mixture using a friendly environment binder material. Fly ash (FA) and silica fume (SF) were used to replace a certain part of the Portland Cement Composite (PCC). The maximum FA replacement referred to the proportions of the FA percentage in the massive paving industry (25%) and the maximum SF replacement (6%) as recommended by ACI 225R-10. The highest 90-day compressive strength gained by specimens of 12% PCC replacement by FA (5.87 MPa), which is 10.2% higher compared to the porous concrete compressive strength which binder composed of 12% FA and 6% SF replacement. The permeability varies at 28 days, but at the age of 90 days, the porous concrete permeability almost evenly, so that the influence of the 6% silica fume in the mixture is not indicated. The ratio of 6% replacement of cement by silica fume with no fly ash gave the highest permeability of 1.4 cm/s, approaching the previous research conducted by Schaefer, et al (2006), while at the age of 90 days the permeability of porous concrete (1.11 cm/s) closed with the results done by Montes (2006).

Optimization of Concrete Porous Mix Using Slag as Substitute Material for Cement and Aggregates

In recent years, sustainability and environmental effect of concrete became the main concern. Substituting cement with the other cementitious material without decreasing mechanical properties of a mixture could save energy, reduce greenhouse effect due to mining, calcination and limestone refining. Therefore, some industrial by-products such as fly ash, silica fume, and Ground Iron Blast Furnace Slag (GIBFS) would be used in this study to substitute cement and aggregate. This substitution would be applied on the porous concrete mixture to minimize the environmental effect. Slag performance will be optimized by trying out variations of fly ash, silica fume, and slag as cement substitution material in mortar mixture. The result is narrowed into two types of substitution. First, reviewed from the fly ash substitution effect on binder material, highest compressive strength 16.2 MPa was obtained from mixture composition 6% fly ash, 3% silica fume and 17% grinding granular blast-furnace slag. Second, reviewed from slag types as cement substitution and silica fume substitution, highest compressive strength 15.2 MPa was obtained from mortar specimens with air-cooled blast furnace slag. It composed with binder material 56% Portland composite cement, 15% fly ash, 3% silica fume and 26% air-cooled blast furnace slag. Considering the cement substitution, the latter mixture was chosen.

Laboratory Assessment of the Infiltration Capacity Reduction in Clogged Porous Mixture Surfaces

Permeable pavements have been used widely across the world to manage urban stormwater. The hydrological behaviour of permeable surfaces is a complex process affected by many factors, such as rainfall intensity, rainfall duration, pavement geometrical conditions, and clogging level of the permeable surface, amongst others. This laboratory study was carried out to assess the influence of clogging level and rainfall intensity on the infiltration capacity of porous mixture surfaces used in Permeable Pavement Systems (PPS). Porous Concrete (PC) and Porous Asphalt (PA) mixtures with different air void contents (15%, 20%, and 25%) were subject to different clogging scenarios by using varying sediment loads (0, 500, and 1000 g/m2). Permeability experiments were carried out for each clogging scenario through a new rainfall simulator specially developed, tailored, and calibrated for the laboratory simulation of a wide range of rainfall events. Permeability measurements were taken under all different scenarios as a result of the combination of the different rainfall events (50, 100, and 150 mm/h) simulated over the specimens of porous mixtures and the sediment loads applied to them. The results showed that the PC mixtures tested perform better than the PA ones in terms of infiltration capacity, showing less potential for clogging and being more easily cleaned by the wash-off produced by the simulated rainfall events.