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Pervious pavements emerge as an alternative for good management of surface runoff, providing the opportunity to quickly and efficiently reduce the potential for flooding and reuse rainwater. However, the mechanical and hydraulic performance of the material have been extensively evaluated at the laboratory level, leaving aside how the material will behave in the field and how its exposure will accelerate the loss of its hydraulic properties (clogging). In this sense, this research evaluated the mechanical and hydraulic performance of permeable concrete pavements in an experimental field that simulates the working conditions of the material, where properties such as compressive strength, tensile strength, porosity, and permeability were evaluated, as well as the loss of hydraulic efficiency due to clogging. This is to increase the knowledge of the material to provide construction and quality control guidelines that guarantee the correct functioning of this type of pavement, considering its great contribution to sustainability. [ABSTRACT FROM AUTHOR]

Highlights • The CFD-DEM model reveals the pore clogging mechanism and clogging development. • The factors that influence clogging development are researched. • Relationship between clogging depth and the sediments size distribution is studied. Abstract The most distinguished characteristic of pervious concrete is its connected porosity that allows water to percolate. And the permeable capacity will decrease rapidly once the pervious concrete is clogged by the sediments. Despite the relationship between permeability and clogging is extensively researched, there is limited information about pore clogging mechanism in pervious pavements. The aim of this paper is using the computational fluid dynamics – discrete element method (CFD-DEM) model to numerically reveal the pore clogging mechanism and clogging development taking into account of the porosity of pervious pavements, sediments size distribution, the horizontal runoff velocity, and the seepage velocity. Pore clogging is determined by the D l /D s ratio—the equivalent diameter of aggregate particles (D l) to equivalent diameter of sediments (D s). A fitted curve is utilized to depict the tendency of clogging. Sediments secondary movement is revealed. Results show that the well-graded sands is able to percolate into the depth of 30 mm in pervious pavements; coarse sands will settle on the shallow surface within depth of 20 mm in pervious pavements; and fine sands will percolate into the depth of 60–100 mm in pervious pavements. As the increase of porosity, horizontal runoff velocity, and seepage velocity, the sediments will transport into pervious pavements deeply. The cycle simulation of raining and draining shows it has limited influence to clogging. [ABSTRACT FROM AUTHOR]

Conventional impervious pavements have dark surface and large thermal inertia. During summertime they tend to absorb and store solar radiation but negate the evaporative cooling, contributing to the development of urban heat island (UHI). The idea of using cool pavements to mitigate the UHI has gained momentum recently. This review synthesizes the existing definition, physical mechanism, and typical cooling techniques of cool pavements, presenting the influence of cool pavements on the urban thermal environment. Benefits, penalties, costs and policies for the applications of cool pavements are presented with special emphasis on reflective pavements and evaporative pavements. The review suggests that the definition of cool pavements remain incomplete; that the influence of cool pavements on the air temperature in the urban canopy layer is unknown; and that the impact of cool pavements on the thermal conditions of adjacent buildings and pedestrians remains unknown. Many speculations of using cool pavements to battle the UHI effect need refinements and validations. Heat-harvesting pavements seem interesting because they not only stay cool but harness renewable energy. However, the results from the heat-harvesting pavement prototype require scrutiny on the power output, durability, and lifetime of the pavement system. Future studies are expected to understanding the impacts of cool pavements on pedestrian thermal stress, on adjacent building’s energy loads, and on the air temperature in the urban canopy layer. [ABSTRACT FROM AUTHOR]

Runoff is one of the main sources of contamination in urban areas, since water can transport pollutants from many different media, among which the hydrocarbons generated by vehicles have an especially significant relevance. Under this premise, the study of geotextiles used as water purification layers within pervious pavement structures becomes a crucial issue, since these fabrics have proved to be a suitable environment for the development of biofilms, which are groups of microorganisms capable of reducing the presence of hydrocarbons. For this reason, this paper proposes a first test to assess the capacity of ten different geotextiles by immersing them in a culture medium prepared to favour the growth of a microbial community. The results showed the major importance of geotextile thickness in the generation of biomass and its relationship to the manufacturing process of the fabric, either heat-sealing or needle-punching. Consequently, a second test was developed to measure the mechanical behaviour of a geotextile of each type when buried in a microbially active soil under different conditions. The comparison between exposed and control samples revealed the maintenance of strength-related properties of geotextiles in the presence of microorganisms. [ABSTRACT FROM AUTHOR]

Most available water resources in the world are used for agricultural irrigation. Whilst this level of water use is expected to increase due to rising world population and land use, available water resources are expected to become limited due to climate change and uneven rainfall distribution. Recycled stormwater has the potential to be used as an alternative source of irrigation water and part of sustainable water management strategy. This paper reports on a study to investigate whether a sustainable urban drainage system (SUDS) technique, known as the pervious pavements system (PPS) has the capability to recycle water that meets irrigation water quality standard. Furthermore, the experiment provided information on the impact of hydrocarbon (which was applied to simulate oil dripping from parked vehicles onto PPS), leaching of nutrients from different layers of the PPS and effects of nutrients (applied to enhance bioremediation) on the stormwater recycling efficiency of the PPS. A weekly dose of 6.23 × 10−3 L of lubricating oil and single dose of 17.06 g of polymer coated controlled-release fertilizer granules were applied to the series of 710 mm × 360 mm model pervious pavement structure except the controls. Rainfall intensity of 7.4 mm/h was applied to the test models at the rate of 3 events per week. Analysis of the recycled water showed that PPS has the capability to recycle stormwater to a quality that meets the chemical standards for use in agricultural irrigation irrespective of the type of sub-base used. There is a potential benefit of nutrient availability in recycled water for plants, but care should be taken not to dispose of this water in natural water courses as it might result in eutrophication problems. [ABSTRACT FROM AUTHOR]

Multi-criteria decision making methods (MCDM) have been widely used throughout the last years to assist project contractors in selection processes related to the construction field. Sustainable urban drainage systems (SUDS) are an especially suitable discipline to implement these techniques, since they involve important impacts on each branch of sustainability: economy, environment and society. Considering that pervious pavements constitute an efficient solution to manage urban stormwater runoff as a source control system, this paper presents a multi-criteria approach based on the Integrated Value Model for Sustainable Assessments (MIVES) method to facilitate their proper selection. Given the lack of accurate information to shape the behavior of the alternatives regarding some of the criteria defining the decision-making environment, a series of variables are modeled by executing stochastic simulations based on the Monte Carlo methods. Additionally, a group of ten experts from various sectors related to water management was requested to provide their opinions about the importance of the set of selected criteria, according to the comparison levels of the Analytic Hierarchy Process (AHP). These judgments are converted into triangular fuzzy numbers, in order to capture the vagueness that human attitude entails when making judgments. A case of study in which the three major types of pervious pavements (porous asphalt, porous concrete and interlocking concrete pavers) are evaluated is presented to demonstrate the potential of the model. [ABSTRACT FROM AUTHOR]

Five litres of lubricating oil and two 8.5 litre batches of diesel were deposited on each of two hydraulically isolated experimental enhanced pervious pavement parking bays. The 50 mm aggregate subbases of the two bays were of either recycled concrete or crushed limestone. The bays were constructed in such a way that a near-surface gravity separator was created by the arranging of the outlet pipes such that a permanent pool of water was maintained in the system and water could only enter from below the level of any floating oil. Dissolved/dispersed hydrocarbons were measured at acceptable concentrations when monitoring was carried out over a period of approximately 5 months. The maximum concentration was 7.2 mg/l and of all the samples collected only 3% exceeded the 5 mg/l limit applied in the UK for a class 1 interceptor, and the majority of samples had hydrocarbon concentrations of less than 2 mg/l. Much more significant is the fact that no free product was discharged from either system up to the time the experiment was dismantled 2 years from the first oil application despite the fact that sufficient hydrocarbon had been added to each pavement to produce a film on a water surface of over 500 hectares. [ABSTRACT FROM AUTHOR]

Pervious pavements are an effective stormwater treatment technology. However, their performance under variable drying and wetting conditions have yet to be tested, particularly under a continuous time scale. This paper reports on the clogging behaviour and pollutant removal efficiency of three pervious pavement types over 26 accelerated years. These pavements were monolithic porous asphalt (PA), Permapave (PP) and modular Hydrapave (HP). Over a cycle of 13 days, the period of which was equivalent to the average annual Brisbane, Australia rainfall (1,200 mm), the pavements were randomly dosed with four different flows. Drying events of 3 h duration were simulated during each flow. Inflow and outflow samples were collected and analysed for Total Suspended Solids (TSS), Total Phosphorus (TP) and Total Nitrogen (TN). To evaluate the rate of clogging, a 1 in 5 year Brisbane storm event was simulated in the 6th, 8th, 12th, 16th, 20th and 24th week. Under normal dosing conditions, none of the pavements showed signs of clogging even after 15 years. However, under storm conditions, both PA and HP started to clog after 12 years, while PP showed no signs of clogging after 26 years. The drying and various flow events showed no effects in TSS removal, with all systems achieving a removal of approximately 100%. The average TP removal was 20% for all flows except for low flow, which had a significant amount of leaching over time. Leaching from TN was also observed during all flows except high flow. The TSS, TP and TN results observed during storm events were similar to that of high flow. [ABSTRACT FROM AUTHOR]

Geotextiles incorporating inorganic nutrients (particularly phosphorous) to enhance the growth of oil degrading microoganisms when geotextiles are used in pervious pavement applications have been shown to be effective in the past. However the cost and manufacturing difficulties have been a barrier to their use. A polypropylene random mat geotextile incorporating an alternative polymer additive as a source of phosphorus has been investigated as a potential self-fertilising geotextile. Experiments are reported which investigate nutrient leach rates, biofilm formation and biodegradation activity. [ABSTRACT FROM AUTHOR]

Pervious pavements are drainage techniques that improve urban water management in a sustainable manner. An experimental pervious pavement parking area has been constructed in the north of Spain (Santander), with the aim of harvesting good quality rainwater. Forty-five pervious pavement structures have been designed and constructed to measure stored water quantity and quality simultaneously. Ten of these structures are specifically constructed with different geotextile layers for improving water storage within the pavements. Following the confirmation in previous laboratory experiments that the geotextile influenced on water storage, two different geosynthetics (Inbitex and a One Way evaporation control membrane) and control pervious pavements with no geotextile layers were tested in the field. Weather conditions were monitored in order to find correlations with the water storage within the pervious pavement models tested. During one year of monitoring the three different pervious pavement types tested remained at their maximum storage capacity. The heavy rain events which occurred during the experimental period caused evaporation rates within the pervious pavements to be not significant, but allowed the researchers to observe certain trends in the water storage. Temperature was the most closely correlated weather factor with the level of the water stored within the pervious pavements tested. [ABSTRACT FROM AUTHOR]

Pervious pavements in car parks and driveways reduce the peak runoff rate and the quantity of runoff discharged into urban drains as well as improve the stormwater quality by trapping the sediments in the infiltrated water. The paper focuses on presenting results from the laboratory tests carried out to evaluate water quality improvements and effects of long-term decrease in infiltration rates with time due to sediments trapping (clogging) within the pavement pores. Clogging was not found to be a major factor affecting pervious pavement performance after simulating 17 years of stormwater quality samples. [ABSTRACT FROM AUTHOR]

The city of Melbourne, Australia is experiencing a water crisis with potable water storage reservoirs at an all time low. With increasing urbanisation there is an ever increasing need to research and explore sustainable water management initiatives. There is potential to minimise the negative impacts of stormwater runoff and augment dwindling supplies of potable water through adoption of pervious paving technology. The traditional approach to stormwater management has focused on constructing drainage networks to carry stormwater away from developed areas as quickly as possible to avoid the risk of flooding. The main aim of this research project was to establish relationships between rainfall intensity, infiltration rate and pervious pavement runoff and to examine the improvement to stormwater quality after infiltrating through pervious pavements. This paper describes the laboratory experiment set-up to determine the infiltration patterns and stormwater quality improvement for simulated storms precipitating on pervious pavements. Next, the scaling-up of the experimental rig to a field-based trial is explained. Preliminary results from this work are presented to demonstrate the potential benefits of pervious pavements in the Australian landscape. [ABSTRACT FROM AUTHOR]

Pervious pavements are one of the most used construction techniques among the Sustainable Urban Drainage Systems (SUDS). The objective of this article is to analyse the energy life cycle and the life cycle cost of stormwater harvesting systems using pervious pavements models in order to compare and evaluate the differences and verify what influences the profitability and sustainability. The method proposed started with the definition of pervious pavement models based on literature review. The main characteristic of the models analysed was the use of porous asphalt with different underlying layers, i.e. thickness and material. The hydrological-hydraulic design of the pavements was also assessed. The potential for potable water savings due to harvesting stormwater from a parking lot was estimated for a public building in Florianópolis, southern Brazil. The models were compared to identify what most influences the potable water savings, the profitability and the sustainability of the systems. The maximum potable water savings found were 42%. It was also observed that the overall consumption of the building has been decreasing over the years, and the yearly rainfall has increased, which leads to a higher potential. In the current water consumption pattern, none of the systems evaluated was profitable or presented sustainability, evaluated herein as negative energy balance. However, it was verified that if analysed comparatively with non-pervious pavement, it was profitable to use stormwater harvested from the pervious pavement. Thus, it can be concluded that stormwater harvesting systems in combination with pervious pavements are promising, serving as SUDS and saving money for users. It is also noticeable that the use of porous asphalt is not recommended when aiming for systems with low embedded energy. Water consumption data, rainfall data and potential for potable water savings by harvesting stormwater from a parking lot of a public building in Florianópolis, Brazil. Image 1 • Stormwater was assessed to be harvested for non-potable uses in a public building. • The hydrological-hydraulic design of the reservoir course was assessed. • The pervious pavement system was economically feasible compared to a non-pervious one. [ABSTRACT FROM AUTHOR]