Showing papers on "Pervious concrete published in 2010"
TL;DR: In this article, the authors focused on the balance between permeability and strength properties of polymer-modified pervious concrete (PMPC) mixtures, which included natural sand and fiber to enhance the strength properties.
332 citations
TL;DR: In this paper, the pore size distribution in pervious concretes is modeled using a Weibull probability distribution function and pore connectivity factor is used to predict the permeability of pervious concrete.
292 citations
TL;DR: In this article, a new type of permeable concrete with enhanced structural strength was developed and various mix designs were attempted and their effects on the compressive strength and permeability of the new concrete were investigated.
217 citations
25 Nov 2010-Materials Science and Engineering A-structural Materials Properties Microstructure and Processing
TL;DR: In this paper, the pore structure features such as pore area fractions, pore sizes, mean free spacing of the pores, specific surface area, and the three-dimensional pore distribution density are extracted using image analysis methods.
Abstract: Properties of a random porous material such as pervious concrete are strongly dependent on its pore structure features, porosity being an important one among them. This study deals with developing an understanding of the material structure–compressive response relationships in pervious concretes. Several pervious concrete mixtures with different pore structure features are proportioned and subjected to static compression tests. The pore structure features such as pore area fractions, pore sizes, mean free spacing of the pores, specific surface area, and the three-dimensional pore distribution density are extracted using image analysis methods. The compressive stress–strain response of pervious concretes, a model to predict the stress–strain response, and its relationship to several of the pore structure features are outlined. Larger aggregate sizes and increase in paste volume fractions are observed to result in increased compressive strengths. The compressive response is found to be influenced by the pore sizes, their distributions and spacing. A statistical model is used to relate the compressive strength to the relevant pore structure features, which is then used as a base model in a Monte-Carlo simulation to evaluate the sensitivity of the predicted compressive strength to the model terms.
196 citations
TL;DR: In this article, a pore size to clogging particle size ratio is found to be the most conducive to particle retention, and an idealized three-dimensional geometry obtained from two-dimensional planar images of pervious concrete sections is used, along with a probablistic particle capture model to predict particle retention associated with clogging material addition and simulated runoff.
Abstract: The ability of in-place pervious concretes to effectively drain storm water runoff gradually reduces as it becomes clogged due to the ingress of fine particles into its pore structure. This study systematically investigates several pervious concrete mixtures propor- tioned using different size aggregates and their blends on their propensity to clogging so as to bring out the influence of pore structure features on particle retention and the consequent permeability reduction. A finer and a coarser sand are used as clogging materials and the experimental study on permeability reduction as a result of particle retention is carried out using a falling head permeability cell. Significant permeability reductions are observed when finer sand is used as the clogging material. A certain effective pore size to clogging particle size ratio is found in this study, that is most conducive to particle retention. Thus pervious concrete specimens of similar porosity, having very large 5-6 mm or very small 1-2 mm pore sizes are found to be less susceptible to clogging under the conditions of this study. An idealized three-dimensional geometry obtained from two-dimensional planar images of pervious concrete sections is used, along with a probablistic particle capture model to predict particle retention associated with clogging material addition and simulated runoff. The trends in the predicted particle retention and the experimentally determined permeability reduction agree well. A "clogging potential" is defined in this paper, either as a ratio of the porosity reduction because of clogging to the initial porosity, or as a ratio of the permeability reduction to the permability in the unclogged state. DOI: 10.1061/ASCEMT.1943-5533.0000079 CE Database subject headings: Concrete; Clogging; Porosity; Permeability; Experimentation. Author keywords: Pervious concrete; Pore structure; Clogging; Porosity; Permeability; Clogging potential; Particle capture model.
152 citations
TL;DR: In this article, a series of tests designed to determine the specific role coarse aggregate has on the freeze-thaw durability of pervious concrete using the ASTM C666A procedure is described.
Abstract: Pervious concrete is becoming more common as a storm-water management tool in freeze-thaw climates. One of the main concerns or obstacles preventing a more widespread application is the aspect of freeze-thaw durability, whether perceived or actual. This paper describes a series of tests designed to determine the specific role coarse aggregate has on the freeze-thaw durability of pervious concrete using the ASTM C666A procedure. 17 different coarse aggregate samples were obtained from locations across the United States and Canada. Pervious concrete mixtures were placed using a mixture proportion previously determined as freeze-thaw durable. The range of durable aggregate gradations clearly defined a gradation specification and suggestions are made for optimizing the gradation with a small portion of sand. Mixtures with excellent freeze-thaw performance contained either granite or highly durable river gravel. The impact of aggregate angularity on mixture proportions and ultimate yield is also discussed.
114 citations
TL;DR: In this article, the influence of aggregate type on the mechanical and acoustic characteristics of porous concrete is systematically investigated, and a sound absorbing porous concrete with a maximum absorption coefficient of approximately 1.00 is developed, and the minimum absorption coefficient is shown to be more than 0.60 with a frequency of 400-Hz or above.
111 citations
TL;DR: In this article, a field test device, called the embedded ring infiltrometer, was developed for evaluating the infiltration rates of newly installed pervious concrete pavements and the usefulness of rejuvenation methods in restoring their hydraulic performance.
Abstract: Pervious concrete pavements in low-traffic urban areas such as parking lots reduce storm water runoff and also minimize water pollution. However, there are concerns about their expected clogging and consequential reduction of hydraulic performance in the long run. The pervious concrete pavements can be declogged using rejuvenation methods such as vacuum sweeping, or pressure washing, or a combination of both. This paper presents the results of our study that focused on the hydraulic performance of pervious concrete pavements. The study included field and laboratory investigations to evaluate the infiltration capacities of the pervious concrete cores and the underlying soils and the usefulness of rejuvenation methods in restoring their hydraulic performance. As a result of this research program, a new field test device, called the embedded ring infiltrometer, was developed for evaluating the infiltration rates of newly installed pervious concrete pavements. The results of this study indicate that the rejuvenation methods can substantially restore the performance of pervious concrete pavements for better management of storm water.
111 citations
TL;DR: In this article, the results of acoustic absorption modeling of porous concrete considering the gradation and shape of aggregates and void ratio are presented, and the predicted acoustic absorption spectra are compared with experimental results to verify the proposed acoustic absorption modelling approach.
86 citations
TL;DR: In this article, a parking lot in eastern North Carolina consisting of four types of side-by-side permeable pavement and standard asphalt was monitored from January 2007 to July 2007 for water quality differences among pavement types.
Abstract: A 1 year-old parking lot in eastern North Carolina consisting of four types of side-by-side permeable pavement and standard asphalt was monitored from January 2007 to July 2007 for water quality differences among pavement types. The four permeable sections were pervious concrete (PC), two different types of permeable interlocking concrete pavement (PICP) with small-sized aggregate in the joints and having 12.9% (PICP1) and 8.5% (PICP2) open surface area, and concrete grid pavers (CGP) filled with sand. The site was located in poorly drained soils, and all permeable sections were underlain by a crushed stone base with a perforated pipe underdrain. Composite, flow-weighted samples of atmospheric deposition and asphalt runoff were compared to those of permeable pavement subsurface drainage for pH, TN, NO2,3 –N , TKN, NH4 –N , and ON concentrations and loads. All pavements buffered acidic rainfall pH ( p<0.01 ) . The pH of permeable pavement subsurface drainage was higher than that of asphalt runoff ( p<0.01 ...
76 citations
TL;DR: In this paper, the authors present a laboratory procedure mimicking a series of catastrophic clogging cycles with clay laden runoff, and the results indicate that extreme events with substantial deposition of clay on a pervious concrete pavement will substantially reduce its service capability, even temporarily fully clogging the pavement.
Abstract: Pervious concrete is a novel paving material with macropores that aid in maintaining natural hydrologic infiltration rates on developed properties. There is a concern that the pores in the pervious concrete might clog due to long-term deposition of fine materials in runoff, or due to a catastrophic event(s) such as the failure of upstream erosion control measures or flooding. This research focuses on these extreme events and presents a laboratory procedure mimicking a series of catastrophic clogging cycles with clay laden runoff. It is predicted that the clay materials would tend to remain near the surface of pervious concrete systems since most placements have a vertical porosity distribution with the smaller pores near the top. The cores used were from actual field placements and the results indicate that extreme events with substantial deposition of clay on a pervious concrete pavement will substantially reduce its service capability, even temporarily fully “clogging” the pavement. However, most of the...
TL;DR: In this paper, a computational procedure is employed to predict the permeability of 12 different pervious concrete mixtures from three-dimensional (3D) material structures reconstructed from starting planar images of the original material.
Abstract: The permeability of pervious concrete is discussed in this paper. Transport properties of porous materials such as pervious concretes are inherently dependent on a variety of pore structure features. Empirical equations are typically used to relate the pore structure of a porous material to its permeability. In this study, a computational procedure is employed to predict the permeability of 12 different pervious concrete mixtures from three-dimensional (3D) material structures reconstructed from starting planar images of the original material. Two-point correlation (TPC) functions of the two-dimensional (2D) images from real pervious concrete specimens are employed along with the measured volumetric porosities in the reconstruction process. The pore structure features of the parent material and the reconstructed images are found to be similar. The permeabilities predicted using Darcy’s law applied to the reconstructed structures and the experimentally measured permeabilities of pervious concretes are found to be in reasonably good agreement. The 3D reconstruction process provides a relatively inexpensive method (instead of methods such as X-ray tomography) to explore the nature of the pore space in pervious concretes and predict permeability, thus facilitating its use in understanding the changes in pore structure as a result of changes in mixture proportions.
TL;DR: In this article, a research study was conducted to incorporate Recycled Concrete Aggregate (RCA) into pervious concrete to create a very sustainable concrete product for paving.
Abstract: Pervious concrete with minimal fine aggregate and a high void content is a green alternative to conventional pavements. Pervious concrete allows water to infiltrate through the pavement and thereby reduces the requirement for storm water management systems. Virgin aggregate sources within Canada are limited, and other sources need to be evaluated for use. Recycled concrete aggregate (RCA) is obtained from decommissioned curbs and gutters, sidewalks, and parking lots. Using RCA in new concrete offers several environmental advantages: reducing dumping at landfill sites, reducing gravel mining, and reducing hauling of virgin aggregate and therefore reducing emissions. The purpose of a research study was to incorporate RCA into pervious concrete to create a very sustainable concrete product for paving. The research methodology involved substituting the coarse aggregate in the pervious concrete with 15%, 30%, 50%, and 100% RCA. Cylinders were cast in the laboratory for each percentage of RCA and a control mix ...
TL;DR: In this paper, the effectiveness of pervious concrete pavement in environmental site design requires consistent design procedures integrating the structural and material properties of the pavement with hydrologic performance of the pervious pavement system.
Abstract: The effective use of pervious concrete in environmental site design requires consistent design procedures integrating the structural and material properties of the pervious concrete pavement with hydrologic performance of the pervious concrete system. Design procedures to size pervious concrete storm-water systems are presented based on criteria for freeze-thaw protection and drawdown reliability. Hydrologic performance criteria are quantified by an effective curve number, estimated from simulated routing of design storm hydrographs using standard storm-water computations. Combining operational design criteria with the evaluation of hydrologic perfor- mance criteria, as an effective curve number, integrates pervious concrete systems with traditional storm-water management practice and emerging standards for environmental site design.
TL;DR: In this paper, the effects of aggregate size and gradation on the unit weight, strength, porosity, and permeability of pervious concrete mixtures were determined, and the results indicated that as the porosity increased, strength decreased, and a range of uniformity coefficients C u.
Abstract: The purpose of this research was to determine the effects of aggregate size and gradation on the unit weight, strength, porosity, and permeability of pervious concrete mixtures. The water-cement ratio (w/c) and cement-aggregate ratio (c/a) were kept constant at 0.29 and 0.22, respectively, with a design unit weight of 2002 kg/m 3 (125 lb/ft 3 ). Fifteen different aggregate gradations were tested and categorized according to nominal maximum aggregate sizes (NMASs) of 9.5, 12.5, and 19.0 mm (0.38, 0.49, and 0.75 in.) and had a range of uniformity coefficients C u . The results indicated that as the porosity increased, strength decreased and permeability increased. In general, as the C u of the aggregate increased-that is, the gradation became less uniform or single-sized and more well-graded-the strength also increased, whereas the porosity and permeability decreased. There appeared to be an optimum/pessimum C u range in which the strength of the pervious concrete reached a maximum and the permeability reached a minimum.
TL;DR: Temperature was the most closely correlated weather factor with the level of the water stored within the pervious pavements tested, and the researchers observed certain trends in the water storage.
TL;DR: In this article, the physical and mechanical properties as well as the seawater purification characteristics of water-permeable concrete using recycled aggregate, granular artificial zeolite, silica fume and glass fiber were investigated and analyzed.
Abstract: This study investigated and analyzed the physical and mechanical properties as well as the seawater purification characteristics of water-permeable concrete using recycled aggregate, granular artificial zeolite, silica fume and glass fiber in order to present effective utilization of waste concrete aggregate and derive a method to improve the performance and seawater purification characteristics of water-permeable concrete. The strength test result showed that the strength increased as the mixing ratio of the recycled aggregate was increased. However, it demonstrated the characteristics of greater compressive strength and flexural strength than plain concrete by 50 and 75%, respectively. The result of measurement for the dissolved oxygen consumption amount as well as T-N (total nitrogen) and T-P (total phosphorous) after the water-permeable concrete was immersed in the artificial water channel indicated that as the target void ratio was greater, the seawater purification performance was more excellent. In addition, it was found that the mixing of the granular artificial zeolite is effective for seawater purification. Therefore, it was discovered that even though the aggregate was replaced with recycled aggregate when making water-permeable concrete for seawater purification, if an appropriate amount of admixture was mixed, the recycled aggregate was effective for the physical and mechanical properties as well as the seawater purification characteristics. It was thought that the appropriate mixing ratio of the recycled aggregate was approximately 50% when the target void ratio was set to 20%.
TL;DR: In this article, the authors evaluated the resistance of pervious concrete to degradation during freeze-thaw cycling under different soil clogging and water saturation conditions, and found that specimens that were clogged with soil or completely submerged in water, or both, were damaged at a significantly faster rate than those specimens that remained unclogged and unsaturated.
Abstract: The objective of this research was to evaluate the resistance of pervious concrete to degradation during freeze-thaw cycling under different soil clogging and water saturation conditions. Laboratory testing of freeze- thaw durability involved two levels of soil clogging and two water saturation conditions in a full-factorial experimental design, and field testing involved measurements of stiffness and compressive strength on clogged and unclogged locations of an experimental pervious concrete slab placed in northern Utah. Both experimental factors, together with their interaction, were determined to be statistically significant in this research. Specimens that were clogged with soil or completely submerged in water, or both, were damaged at a significantly faster rate than those specimens that remained unclogged and unsaturated. The average number of freeze-thaw cycles to failure was 93 for clogged specimens compared with 180 for unclogged specimens, and 80 for saturated specimens compared with 193 for un...
01 Jul 2010
Journal Article•
TL;DR: Pervious concrete is a special high porosity concrete used for flatwork applications that allows water from precipitation and other sources to pass through, thereby reducing the runoff from a site and recharging ground water levels as mentioned in this paper.
Abstract: Pervious concrete is a special high porosity concrete used for flatwork applications that allows water from precipitation and other sources to pass through, thereby reducing the runoff from a site and recharging ground water levels. Its void content ranges from 18 to 35% with compressive strengths of 400 to 4000 psi (28 to 281 kg/cm). The infiltration rate of pervious concrete will fall into the range of 2 to 18 gallons per minute per square foot (80 to 720 litres per minute per square meter). Typically, pervious concrete has little or no fine aggregate and has just enough cementitious paste to coat the coarse aggregate particles while preserving the interconnectivity of the voids. Pervious concrete is traditionally used in parking areas, areas with light traffic, pedestrian walkways, and greenhouses and contributes to sustainable construction.
TL;DR: The damaging impact of deicing chemicals on portland cement pervious concrete materials was investigated in this paper, where two concrete mixes (with and without latex modification) were subjected to three deicing agents (sodium chloride, calcium chloride, and calcium-magnesium acetate) under a freezing-thawing or drying-wetting condition.
Abstract: The damaging impact of deicing chemicals on portland cement pervious concrete materials was investigated. Two concrete mixes (with and without latex modification) were subjected to three deicing chemicals (sodium chloride, calcium chloride, and calcium-magnesium acetate) under a freezing-thawing or drying-wetting condition. Two deicing chemical application methods (saturated and drained) were employed. The impact of deicing chemicals on the concrete was evaluated based on concrete mass and strength losses. Of the deicing chemicals studied, the calcium chloride solution caused the most damage, while the calcium magnesium acetate caused the least. The saturated scaling test method, followed according to ASTM C672, provided much higher mass loss of tested concrete samples when compared with a modified, more realistic drained test method.
TL;DR: In this article, the construction and performance of a PCPC overlay constructed at the Minnesota Road Research Project low-volume roadway test facility to determine the effectiveness of pervious concrete as an overlay.
Abstract: Portland cement pervious concrete (PCPC) has shown great potential to reduce roadway noise, improve splash and spray, and improve friction as a surface wearing course. A study is under way at Iowa State University and the National Concrete Pavement Technology Center to develop mix designs and procedures for PCPC overlays for highway applications. A report is produced on the construction and performance of a PCPC overlay constructed at the Minnesota Road Research Project low-volume roadway test facility to determine the effectiveness of pervious concrete as an overlay. Issues related to construction of the overlay are described, as are results of field tests to characterize the condition of the pavement 7 months following construction, to determine flow characteristics of the overlay, and to characterize the tire-pavement noise of the overlay. Results of these studies show that effective PCPC overlays can be designed for wearing course applications.
Journal Article•
Patent•
22 Dec 2010
TL;DR: In this article, a stone-simulating pervious concrete floor and a construction method for constructing a pervious road surface is described. But the pervious floor is not considered in this paper.
Abstract: The invention relates to a stone-simulating pervious concrete floor and a construction method thereof. The concrete floor includes a tamped foundation, a crushed stone layer, a pervious concrete structural layer and a pervious concrete surface layer from bottom to top; the pervious concrete surface layer is a stone-simulating pervious concrete surface layer, which adopts the following materials and weight ratio: 2100-2300kg/m of river sand; 325-335kg/m of cement; 39-41kg/m of silicon power; 24-26kg/m of Grade I coal ash; 3.4-3.6kg/m of water reducer and 78-80kg/m of tap water. The invention leads the pervious concrete road surface to have water permeability and decoration simultaneously, and improves the water-permeable and air-permeable effect of the concrete road surface on the premise of ensuring the strength of the road surface and having the texture of the concrete road surface.
26 Jul 2010
TL;DR: In this article, an electrically conductive porous asphalt concrete used for induction heating and subsequently healing of cracks is prepared by adding conductive materials (steel fibers and steel wool) in this research.
Abstract: An electrically conductive porous asphalt concrete used for induction heating and subsequently healing of cracks is prepared by adding conductive materials (steel fibers and steel wool) in this research. In this paper, the optimization of steel fiber used for induction heating is reported based on the electrical resistivity, induction heating speed and particle loss resistance of porous asphalt concrete. It is found that porous asphalt concrete containing steel fiber with smaller diameter or longer steel fiber is more electrically conductive and induction heatable than that containing the same content of steel fiber with bigger diameter or short steel fiber. It is also found that steel wool type 00 with length of 9.5 mm is more effective than short steel fiber type 1 and steel wool type 000 to improve the particle resistance of porous asphalt concrete. Finally, 8% (by volume of bitumen) of steel wool type 00 is considered as the best option used for induction heating in porous asphalt concrete.
Patent•
22 Dec 2010
TL;DR: In this paper, a method for performing foundation treatment by using permeable concrete pipe piles was proposed, which comprises the following steps of selecting a soft soil foundation or a liquefiable foundation for the arrangement of the pipe piles, and arranging the piles along narrow sides in a site, connecting the centers of each row of pipe piles into a straight line and paving a cushion along the straight line.
Abstract: The invention discloses a method for performing foundation treatment by using permeable concrete pipe piles, which comprises the following steps of: selecting a soft soil foundation or a liquefiable foundation for the arrangement of the permeable concrete pipe piles, wherein the permeable concrete pipe pile is a closed pipe pile of which two ends are closed and a pile body is made of permeable concrete; and arranging the piles along narrow sides in a site, connecting the centers of each row of permeable concrete pipe piles into a straight line and paving a cushion along the straight line, wherein the cushion is made of sands or gravels; and the cushion has a width equal to the diameter of the pipe pile and is 20 to 40cm thick. The permeable concrete pipe piles not only function as reinforcement bodies of composite foundations, but also are good drainage channels per se. As the advantages of the composite foundations treated by a drainage consolidation method and a composite foundation method are integrated, the method has the advantages of improving foundation treatment effect, shortening a construction period and saving the engineering construction cost.
06 Apr 2010
TL;DR: In this article, the authors present the results of the infiltration testing on these pervious pavement systems and also present results of these rejuvenation techniques on the performance of the pavements.
Abstract: Pervious pavement systems are being studied for stormwater quality and quantity control and as a major component of low impact development (LID). To assess the potential of several types of pervious pavement systems, the Stormwater Management Academy at the University of Central Florida is studying the behavior of these systems at its field laboratory. These pervious pavements are also considered as part of the new Stormwater Rule in the state of Florida. Research is being conducted on five types of pervious pavements, namely pervious concrete, Flexipave, porous asphalt, and two types of brick pavers. One more pavement system called Filterpave has recently been installed and is currently undergoing testing. This paper will present the results of the infiltration testing on these systems. Keeping in mind the long-term performance and maintenance requirements, these pavements are intentionally being loaded with sediment (sand and fine grained crushed limerock) to simulate clogging as indicated by significant reduction in their infiltration capacity. The pavements are then subjected to a rejuvenation technique using a vacuum sweeper truck. This paper will also present the results of these rejuvenation techniques on the performance of the pavements. This paper aims to update the water resources community on the new developments with these types of pavements.
TL;DR: In this article, the authors developed a computational model to simulate the behavior of pervious concrete under compression, and the results of calculations based on particle flow analysis are compared to the experimental data.
Abstract: With the increasing popularity of pervious concrete as a pavement material, researchers and concrete manufacturers have paid more attention to research needs. Pervious concrete is currently used in low traffic volume areas such as parking lots, footpaths and driveways. This is because it generally has lower strength than conventional concrete. This paper aims at developing a computational model to simulate the behaviour of pervious concrete under compression. Since compressive strength is one of the most important properties for concrete, a virtual model will provide a better understanding of its mechanical performance, which in turn will improve both the mix design and the material strength in the future. The discrete element method was applied and the results of calculations based on particle flow analysis are compared to the experimental data.
01 Jan 2010
TL;DR: In this article, the results of an experimental investigation into the physical and engineering properties of pervious concrete having varying amounts of low calcium fly ash as the cement replacement material were presented.
Abstract: Pervious concrete has an interconnected pore structure that freely allows the passage of water to flow through. This concrete is being used as paving material in the United States for the construction of parking lots, sidewalks and secondary roads. The use of pervious concrete was found to reduce the stormwater runoff to the drainage system and minimising flooding under heavy storm. The production of good quality pervious concrete is necessary to meet specification requirements for the construction of durable concrete pervious pavements. This paper reports and discusses the results of an experimental investigation into the physical and engineering properties of pervious concrete having varying amounts of low calcium fly ash as the cement replacement material. The properties of concrete studied were: porosity, unit weighty, compressive strength, weight loss on drying, free drying shrinkage and water permeability under constant head. The results showed that porosity has significant effect on compressive strength and permeability of pervious concrete. Replacement of cement with fly ash up to 50%, by mass of binder, had no significant effect on the water permeability and shrinkage of the pervious concrete, although marginal effect on strength was noticed.
06 Apr 2010
TL;DR: In this paper, the authors present the findings from 2 pervious pavements, a pervious concrete and a porous asphalt parking lot, studied at the University of New Hampshire Stormwater Center.
Abstract: In northern climates, runoff from standard pavements has varying seasonal effects on the surrounding environment. Year-round runoff carries transportation associated contaminants into surface waters. During the winter and spring, deicing practices for pavements result in high levels of chloride-laden runoff that is both toxic to aquatic biota and degrades drinking water supplies. The use of pervious pavements for parking lots for new and redevelopment projects are one watershed-based strategy that can both mitigate impacts for new development and reverse impacts in areas with redevelopment. This study presents the findings from 2 pervious pavements, a pervious concrete and a porous asphalt parking lot, studied at the University of New Hampshire Stormwater Center. Winter in particular places great demands on pavements however it was observed that due to the well-drained nature of the reservoir base that freeze thaw was limited. Surface infiltration rates, frost penetration, degree of snow and ice cover, and surface friction were measured on a monthly basis to assess winter performance. Frost penetration was observed to reach depths of eighteen inches however, surface infiltration capacities remained in excess of 200-in/hr. Analysis of snow and ice cover and pavement skid resistance demonstrated that up to 75% less salt was needed for porous asphalt to maintain equivalent or better surface conditions as the reference dense mix asphalt lot. The annual median snow and ice surface cover for the porous asphalt lot was not significantly different than the reference lot with salt applications four times greater (p=0.749 @95% CI). The annual median weighted skid resistance for the porous asphalt lot was 12% greater than the reference lot with greater salt application (p=0.061 @95%CI). Pervious concrete did not demonstrate substantial salt reduction capabilities during storm events; however, `black-ice' formation did not occur during freeze-thaw conditions indicating possible annual reductions. Pavement color and shading were found to be major factors influencing the amount and duration of snow and ice cover on the pervious concrete lot.