Showing papers on "Pervious concrete published in 2013"

Use of washed municipal solid waste incinerator bottom ash in pervious concrete

Abstract: Washed municipal solid waste incinerator bottom ash (MSWIBA) was used in this study as a substitute for natural aggregate in pervious concrete. The mix proportions of the concrete were first determined using a vertical flow test. Other tests, including permeability, compressive strength, bending and split tensile strength tests, were also performed. The test results show that the unit weight of the fresh pervious concrete made with MSWIBA was approximately 1653–2080 kg/m 3 and increased with the ratio of cement paste filling. In specimens with the same water–cement ratio, the compressive, bending and split tensile strengths all increased with the ratio of filling paste. The split tensile and bending strengths were approximately 1/9 and 1/4 of the compressive strength, respectively. The connected porosity and permeability coefficients are linearly correlated; both decrease as the filling ratio is increased.

Quantifying Evaporation from Pervious Concrete Systems: Methodology and Hydrologic Perspective

Abstract: Permeable pavements underlain by infiltration beds have been used as storm-water control measures (SCMs) for several decades As a design practice, runoff volume reduction in those systems is attributed exclusively to subsurface infiltration Neglecting evaporation in the hydrologic cycle of permeable pavement systems is based on the perceived insignificance of this factor rather than on scientific evidence This paper presents research designed to fill the knowledge gap in the evaporation behavior of pervious concrete SCMs A laboratory simulation was conducted to identify parameters affecting evaporation from pervious concrete systems and to obtain the evaporation rates typical for summer months in the Philadelphia area Considerations used in the experiment design, methodology, the experimental program, and the results are presented here The depth to water surface and the time since rainfall event were both found to be significant terms in predicting the evaporation rate The concept of influe

Examination of the Material Found in the Pore Spaces of Two Permeable Pavements

Abstract: Clogging of pore space is the leading cause of failure of permeable pavements. A study conducted at Villanova University on two permeable pavements, porous asphalt and pervious concrete, endeavored to answer the question of what materials were depositing in the pore spaces. In 2007, an existing parking lot at Villanova University was retrofitted with a 30 by 9 m section of permeable pavement. Half of the section (15 by 9 m) consisted of pervious concrete, whereas the other half was porous asphalt. The 270 m2 porous pavement area had a drainage area of 730 m2, which was 100% traditional dense-graded (impermeable) asphalt. A stone infiltration bed underlaid the permeable pavements. Intensive vacuuming was performed using an industrial strength vacuum cleaner to extract the material contained in the pore spaces of the pavement surface layer. The material collected was analyzed to determine the grain size distribution, percentage of organic matter, and concentration of metals (copper, lead, and zinc...

Mimicking Bone Healing Process to Self Repair Concrete Structure

Abstract: To repair concrete cracks in difficult or dangerous conditions such as underground structures or hazardous liquid containers, self healing mechanism is a promising alternative method. This research aims to imitate the bone self healing process by putting porous concrete internally in formed and detected by sensors, healing agent can be infused into the porous network so as to fill up voids and seal a crack or cracks in the concrete body. This idea was tested using cylindrical samples. A porous concrete core was placed in the center of the concrete cylinder. Uniaxial direct tensile load was applied to create cracks close to the notch of the sample. A healing action was performed by injecting healing agent manually. The results show that a macro-crack is sealed and strength of concrete is regained. Therefore, the concept is considered as to be feasible for self repair mechanism in concrete.

Pervious Concrete: New Era For Rural Road Pavement

Abstract: Pervious concrete is a relatively new concept for rural road pavement, with increase into the problems in rural areas related to the low ground water level, agricultural problem. Pervious concrete has introduced in rural road as a road pavement material. Pervious concrete as a paving material has seen renewed interest due to its ability to allow waterto flow through itself to recharge groundwater level and minimize storm water runoff. This introduction topervious concrete pavements reviews its applications and engineering properties, including environmentalbenefits, structural properties, and durability.In rural area cost consideration is the primary factor which must be kept in mind. So that in rural areas costly storm water management practices is not applicable. Pervious concrete pavement is unique and effective means to meet growing environmental demands. By capturing rainwater and allowing it to seep into the ground. This pavement technology createsmore efficient land use by eliminating the need for retention ponds, swell, and other costly stormwater management devices.

Cleaning Methods for Pervious Concrete Pavements

Abstract: Pervious concrete paving systems increasingly are being applied as environmentally friendly alternatives to traditional impervious pavements. Pervious concrete (PC) systems have been shown to effectively reduce negative environmental impacts associated with impervious pavements, including stormwater pollution, noise, heat island effects, and soil erosion. Keeping PC pavements viable requires maintaining their ability to infiltrate water. The porous nature of PC invites solids such as soil particles and organic matter carried in storm runoff to become trapped in the surface over time, gradually decreasing infiltration rate (IR). The pavement, if left unmaintained, will become increasingly clogged. Since no standardized recommendation for cleaning PC currently exists, water management agencies in some states do not provide stormwater management credit for using PC systems. This research studied the effectiveness of power blowing, pressure washing, and vacuuming, as well as a combination of these methods for...

Dynamic behavior of porous concretes under drop weight impact testing

Abstract: Porous concrete is used as a construction material in various applications mainly as a permeable cementitious material. However, its response under impact loading is generally not considered. Due to the high percentage of its intentional meso-size air pores, porous concrete has a moderate static strength compared to normal concrete while its dynamic performance is distinctive. Owing to its characteristic of forming multiple cracks, it fractures into small fragments when exposed to impact loading. Therefore, with the aim of designing a special type of concrete to be used in protective structures, porous concrete was investigated. In this study, the impact strengths of different types of porous concretes were analyzed in correlation with their mixture compositions and production technique. The dynamic experiments were performed using a drop weight impact test set-up while the measurements were taken through Laser Doppler velocimetry. According to the results obtained, the aggregate properties and compactive effort, which are coupled to porosity, are the main factors that affect the dynamic performance of porous concrete. © 2013 Elsevier Ltd. All rights reserved.

Pervious concrete and preparation method thereof

Abstract: The invention relates to a pervious concrete and a preparation method thereof. The pervious concrete mainly comprises cement, aggregate, mineral admixtures, water, adhesive, and concrete additive. The pervious concrete is prepared from the components through slurry wrapping and vibration press forming, so that the pervious concrete greatly improves strength, durability and water permeability and prolongs the service life. The strength grade of the pervious concrete achieves C30, the permeation coefficient thereof is more than 2mm/s, antifreeze grade is F150, and the pervious concrete has excellent anti-blocking performance. The problem that the existing pervious concrete cannot be widely popularized due to poor self performances is solved, so that the pervious concrete can be widely used in projects such as squares, sidewalks, road isolation strips, parks and supporting roads.

Correlation between low-order probability distribution functions and percolation of porous concrete

Abstract: Concrete is a multi-phase material whose material properties are strongly affected by phase distribution. It is important to identify the spatial distribution of voids in concrete because voids have a significant effect on mechanical behaviour and percolation. Therefore, a proper method to describe the void distribution of the material is needed. This paper describes how computed tomography (CT) was used to examine and quantify the void distribution of porous concrete specimens. Virtual three-dimensional porous concrete specimens were created using CT. Then, low-order probability distribution functions such as two-point correlation, lineal-path and two-point cluster functions were used to characterise the void distribution. Based on CT image analysis, the correlation of hydraulic conductivity between experiment results and probability distribution functions of porous concrete is examined. It is confirmed that low-order probability functions and percolation of porous concrete are correlated and that the lo...

Fast-curing pervious concrete mix

Abstract: A fast-curing pervious concrete mix made by combining : water; a cementitious material comprising portland cement and a supplementary cementitious material; aggregate sized to form a pervious concrete; a water reducer; a quantity of fibers; and a polymeric bonding agent, the mix curing to a compressive strength of at least 2,000 psi within 24 hours of placement. Also, a method of forming a pervious concrete structure by forming the fast-curing pervious concrete mix, placing the mix in a desired formation, and curing the placed mix, and a pervious concrete obtained by placing and curing the fast-curing pervious concrete mix.

Effect of Mix Proportion on Strength and Permeability of Pervious Concrete for Use in Pavement

Abstract: A study to achieve high-strength, high porosity and permeability pervious concrete pavement was carried out. Mix proportions in terms of cement content, coarse aggregate-cement ratio (CA/C) and water-cement (W/C) ratio were varied. A mix proportion providing the optimal combination of strength and porosity was chosen, and polymer superplasticizers were added to examine their effect on the strength and porosity. Results showed that a water-cement ratio of 0.2 resulted in a dry and brittle mix that led to compressive strength less than 15MPa but a high permeability rate of approximately 20mm/s. A mix with w/c ratio of 0.3 and CA/C ratio of 4.25 resulted in compressive strength of 13.9MPa, flexural strength of 3MPa and high porosity of more than 20%. The use of high cement content of 495kg/m3 in the mix resulted in high compressive strengths of 51.8MPa, flexural strength of more than 4MPa, however permeability was reduced to approximately 1mm/s.

The sustainable use of concrete

Abstract: Introduction References Sustainability Natural History Human Beings and Concrete Genealogy of Sustainability Pillars of Sustainability References Sustainability in Concrete and Construction Environmental Aspects Social and Economic Aspects References Evaluation Systems of Sustainability Life Cycle Assessment (LCA) Environmental Standards for Buildings Systems of Environmental Impact Evaluation Environmental Standards for Concrete Sector Evaluation of Social and Economic Aspects Tools of Environmental Effect Evaluation for Buildings References Technologies for Concrete Sustainability General Concrete Concrete Structures References Sustainable Concrete Technologies: Case Studies CO2 Negative Concrete in Japan Low Carbon High-Flowable Concrete High-Performance Shotcrete Closed-Loop Concrete System on Construction Site Concrete Pavement Ultra-High Strength Fiber Reinforced Concrete Adaptable Super High Rise Residential Buildings Utilization of Thermal Mass of Concrete Pervious Concrete References Future Perspectives Existing Perspectives New Perspectives Wishful Thinking References Index

Evaluation of surface textures and skid resistance of pervious concrete pavement

Abstract: Surface textures had long been recognized as primary factors to provide the skid resistance on pavements; however, no measurement of skid resistance on pervious concrete pavement with various surface texture parameters had been made. Fractal geometry was introduced in the present work to accurately simulate transect contour curves of pervious concrete specimens through fractal interpolation. It is proved that its fractal dimension (D) can be adopted to measure the skid resistance on pervious concrete pavement, overcoming the shortcomings of both macrotexture depth (DT) and British portable pendulum number (NBP). Combined with Fujikawa-Koike tire/road contact model, the optimization method of all surface textures was recommended for designing and constructing excellently skid-resistant and noise-absorptive pervious concrete pavement. In addition, evaluating of the abrasion process and attenuation of the surface textures on concrete pavement slabs was also the focus of this work based on accelerated abrasion test. Results show that the surface textures on pervious concrete pavement slabs is extremely durable, compared to those on conventional grooved or exposed aggregate concrete pavement slabs.

Clogging mechanism of permeable concrete: A review

Abstract: Urbanization results in the conversion of pervious spaces to areas of impervious (paved) surface which creates numerous problems such as erosion, flash floods, pollution of rivers and hot island in city. A sustainable solution to this problem is to use permeable pavements which only began to find application in Australia recently. Permeable pavements can facilitate biodegradation of oils from cars and trucks, help rainwater infiltrate into soil, replenish groundwater, allow tree roots to breathe, and reduce flash flooding, but they have not been widely adopted in Australia due to concerns mainly over reduced structural capabilities and clogging. A research project is being carried out at USQ aiming at understanding the influence of pore structures features and particle deposition on clogging resistance and permeability reduction. Clogging is perceived as a major problem for any type of permeable pavement. Even with vigorous maintenance clogging is common. In the paper, some common types of clogging are discussed first, followed by the clogging effect on the performance of porous concrete mainly related to the change of the porosity and the pore structure properties. Testing methods for measuring porosity and hydraulic conductivity which include both physical testing and image analysis are reviewed in detail.

The Use of Seashell by-Products in Pervious Concrete Pavers

Abstract: Pervious concrete is a green alternative to conventional pavements with minimal fine aggregate and a high void content. Pervious concrete allows water to infiltrate through the pavement, thereby reducing the runoff and the requirement for stormwater management systems. Seashell By-Products (SBP) are produced in an important quantity in France and are considered as waste. This work investigated to use SBP in pervious concrete and produce an even more environmentally friendly product, Pervious Concrete Pavers. The research methodology involved substituting the coarse aggregate in the previous concrete mix design with 20%, 40% and 60% SBP. The testing showed that pervious concrete containing less than 40% SBP had strengths, permeability and void content which are comparable to the pervious concrete containing with only natural aggregate. The samples that contained 40% SBP or higher had a significant loss in strength and an increase in permeability and a void content from the control mix pervious concrete. On the basis of the results in this research, it was found that the natural aggregate can be substituted by SBP without affecting the delicate balance of a pervious concrete mix. Additional, it is recommended that the optimum replacement percentage for SBP in pervious concrete is 40 % direct replacement of natural coarse aggregate while maintaining the structural performance and drainage capabilities of the pervious concrete. Keywords—Seashell by-products, pervious concrete pavers, permeability and mechanical strength.

Non-radioactive environment-friendly energy-accumulation luminous pervious concrete pavement and construction method thereof

Abstract: The invention relates to a non-radioactive environment-friendly energy-accumulation luminous pervious concrete pavement which structurally comprises a soil matrix, a base layer, a reinforced pervious concrete structure layer, a luminous pervious concrete surface layer and a protection layer from bottom to top. The pavement disclosed by the invention has a good ornamental value in daytime, can absorb and storage light energy, can emit light at night to play a role in illumination and indication, has a favorable decoration property and a good energy saving effect and can be widely applied to sidewalks on two sides of courtyards, public areas, scenic spots and driving roads.

Development of High Quality Pervious Concrete Specifications for Maryland Conditions

Abstract: One of the main objectives of this research was to develop preliminary specifications for high quality pervious concrete suitable for use in Maryland State Highway Administration (SHA) projects. The study utilized aggregates that are used in SHA projects and the durability studies that were conducted assumed Maryland weather conditions. Investigations were conducted to enhance the structural and durability characteristics of pervious concrete through the use of different admixtures. The admixtures included cellulose fibers, a delayed set modifier and a viscosity modifier. Pervious concrete specimens were tested for density, void content, compressive strength, split tensile strength, permeability, freeze-thaw durability, and abrasion resistance. Three different types of freeze-thaw durability tests were conducted to mimic potential field conditions including the possibility of clogged pavement. The freeze-thaw durability tests included: fully saturated tests, 50% saturated tests, and 0% saturated dry hard freeze tests. The study found that of the different admixtures tested, cellulose fibers had the largest impact in improving durability. Including cellulose fibers in the pervious concrete mix resulted in significant increases in resistance in all three freeze-thaw durability tests. It also resulted in significant increases in abrasion resistance. By bridging the gap between the coarse aggregates, the cellulose fibers bound the pervious concrete mixture with an interwoven matrix of fibers. This also improved the tensile strength of the pervious concrete. The delayed set modifier resulted in a more fluid mix and in large gains in compressive strength at seven and fourteen days. This admixture may inhibit some of the cement from setting around aggregates and may result in some cement settling to the bottom and forming a less pervious layer. The viscosity modifying admixture created a more workable and easier to mold mix. Its effect on strength and durability were minimal.

Mixture Proportioning Considerations for Improved Freeze-Thaw Durability of Pervious Concrete

Abstract: Recent U.S. Environmental Protection Agency (EPA) Clean Water Act and Energy and Security Act amendments require stormwater management at private, public, and federal installations. Pervious concrete is a highly permeable material used for stormwater management where detention/retention areas can be placed underneath the pavement for increased site utilization. Although pervious concrete has been successfully utilized in the U.S. for over 40 years, the applications in cold climates only began in earnest around 2006. There still is hesitance to use pervious concrete in cold climates from the perceived lack of freeze-thaw durability. The authors have extensive experience using pervious concrete in cold climates and this paper will discuss the mixture requirements and options for good freeze-thaw performance. Since the freeze-thaw durability of pervious concrete is affected by both the mixture and the installation, a companion paper Installation and Maintenance Considerations for Improved FreezeThaw Durability of Pervious Concrete provides a discussion of topics related specifically to installation, construction, and maintenance. The two papers provide a comprehensive discussion of pervious concrete for cold climates.