Daniel Castro-Fresno

Performance of pervious pavement parking bays storing rainwater in the north of Spain

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.

Laboratory analysis of the infiltration capacity of interlocking concrete block pavements in car parks

Interlocking concrete block pavements (ICBPs) have been widely used in car parks to reduce runoff. Researches have demonstrated that clogging is the most influential factor in the reduction of the infiltration capacity of this type of permeable pavement. Nevertheless, there is no laboratory study of the infiltration performance of ICBPs that combines clogging levels with variables related with the topography of car parks such as runoff surface length (R(SL)) and surface slope (S(S)). This paper studies the infiltration behaviour of ICBP during their operational life in a car park using an improved version of the Cantabrian Fixed (CF) Infiltrometer. This laboratory device simulates direct rainfall and runoff from adjacent impervious areas over an ICBPs surface of 0.25 m(2) for different slopes (0, 3, 5, 7 and 10%) and three scenarios of clogging (surface newly built, surface clogged and surface clogged with maintenance). This paper presents the results of the tests and a statistical analysis based on three regression models (corresponding to each clogging scenario) depending on the R(SL) and S(S) variables. All models passed a confidence level of 95%, presenting high R(2) values and showing that R(SL) is a more influential variable than the S(S) for all clogging scenarios.

Maturity Approach Applied to Concrete by Means of Vicat Tests

Contractors would be aided in planning a pavements texturing and finishing times through better knowledge of initial concrete setting time. The authors present a straightforward temperature influence on setting time evaluation method with this in mind. The Freiesleben-Hansen and Pedersen maturity function was used to accomplish this. A Vicat test series was carried out at different temperatures for cement apparent activation energy determination usage in this equation. To determine the correctness of any activation energy found, there was application to the times for a specific penetration resistance to be attained with various water-cement (w/c) ratios and at different temperatures with three different cement types. When equivalent concrete setting time ages were calculated, w/c and setting time linear relationships were obtained at the reference temperature. The authors concluded that temperature influence on concrete setting time evaluation could be performed through the apparent activation energy this method obtained.

Characterization of Infiltration Capacity of Permeable Pavements with Porous Asphalt Surface Using Cantabrian Fixed Infiltrometer

AbstractPorous asphalt is used in Permeable Pavement Systems, but it is sensitive to surface clogging, which leads to a loss in its infiltration capacity. Test methods based on the use of permeable pavement models, which are manufactured in a laboratory and assessed under different clogging conditions, such as slope, rain, and runoff, have been widely applied to the study of permeable pavements with concrete blocks but not to the study of porous bituminous mixtures. The Cantabrian Fixed (CF) Infiltrometer has been used for the study of porous asphalt with void percentages between 20 and 33%. Three clogging scenarios were studied: 1) newly placed surface, 2) surface with an average maintenance level, and 3) clogged surface. Each clogging scenario was tested with five different slopes: 0, 2, 5, 8, and 10% and three repetitions. The direct rainfall simulation was produced by five lines of bubblers over the 0.25 - m2 piece, and the runoff was simulated by one perforated pipe over a plastic ramp at the beginni...

Design and construction of an experimental pervious paved parking area to harvest reusable rainwater

Pervious pavements are sustainable urban drainage systems already known as rainwater infiltration techniques which reduce runoff formation and diffuse pollution in cities. The present research is focused on the design and construction of an experimental parking area, composed of 45 pervious pavement parking bays. Every pervious pavement was experimentally designed to store rainwater and measure the levels of the stored water and its quality over time. Six different pervious surfaces are combined with four different geotextiles in order to test which materials respond better to the good quality of rainwater storage over time and under the specific weather conditions of the north of Spain. The aim of this research was to obtain a good performance of pervious pavements that offered simultaneously a positive urban service and helped to harvest rainwater with a good quality to be used for non potable demands.

Long-term analysis of clogging and oil bio-degradation in a System of Catchment, Pre-treatment and Treatment (SCPT).

Runoff contamination has motivated the development of different systems for its treatment in order to decrease the pollutant load that is discharged into natural water bodies. In the long term, these systems may undergo operational problems. This paper presents the results obtained in a laboratory study with a 1:1 scale prototype of a System of Catchment, Pre-treatment and Treatment (SCPT) of runoff waters. The analysis aims to establish the operational behaviour of the SCPT in the long term with respect to oil degradation and hydraulic conductivity in the geotextile filter. It is concluded that bio-degradation processes take place inside the SCPT and that hydraulic conductivity of the geotextile filtration system decreases slowly with successive simulated runoff events.

Long-Term Simulation of a System for Catchment, Pretreatment, and Treatment of Polluted Runoff Water

The effects of pollutants in runoff on the environment have forced the development of several water treatment systems with the aim of reducing this kind of pollution before its final discharge. Nevertheless, many of these systems do not behave satisfactorily and, additionally, there is a low level of confidence in the treatment performance. This paper introduces the results of research on the long-term performance of a laboratory prototype of a system for catchment, pretreatment, and treatment (SCPT) designed to deal with the polluted runoff water. Solid and oil treatment efficiency were the focus of the study. After 14 consecutive simulated rain events, the treatment efficiency levels achieved by the prototype are higher than 80% of solids and 90% of oils.

Laboratory Study on the Stormwater Retention and Runoff Attenuation Capacity of Four Permeable Pavements

AbstractHydrological behavior of pervious pavements during rainfall events is a complex process that is affected by many factors such as surface type, nature of aggregates, layer thickness, rainfall height, rainfall intensity, and the preceding dry period. In order to determine the influence of construction materials on the runoff attenuation capacity of pervious pavements, 16 laboratory models were created with four different cross sections obtained by combining two pervious surfaces and two subbase aggregate materials. Successive rainfall simulations were applied over the laboratory models, measuring lag times, retained rainfalls, and times to peak, and peak outflows were registered for the simulated rainfalls. The results obtained were grouped depending on the materials used and statistically analyzed in order to compare their stormwater retention and runoff attenuation capacities. Both surface type and subbase aggregate characteristics were proven to influence the attenuation capacity of pervious pave...

Effect of Type of Compaction on Mechanical Properties in Warm-Mix Asphalts

AbstractThis paper compares the effect of type of compaction (impact and gyratory compaction) on mechanical properties (such as water sensitivity and stiffness modulus) in warm-mix asphalts. Moreover, the manufacture and laying temperatures and the use of additives for warm-mix asphalts have been taken into account. The mixes tested have a semidense aggregate gradation with a B-60/70 penetration binder and different types of warm-mix additives have been added. The mixtures compacted by gyratory compactor at different temperatures all displayed good behavior in terms of water sensitivity; in contrast, not all mixtures compacted by impact achieved this. On reducing the manufacturing temperature, the stiffness moduli decreased in all mixtures for both types of compaction, this reduction being less pronounced in the mixes manufactured with the gyratory compactor. The results have been evaluated statistically.

Comparative analysis of the outflow water quality of two sustainable linear drainage systems

Three different drainage systems were built in a roadside car park located on the outskirts of Oviedo (Spain): two sustainable urban drainage systems (SUDS), a swale and a filter drain; and one conventional drainage system, a concrete ditch, which is representative of the most frequently used roadside drainage system in Spain. The concentrations of pollutants were analyzed in the outflow of all three systems in order to compare their capacity to improve water quality. Physicochemical water quality parameters such as dissolved oxygen, total suspended solids, pH, electrical conductivity, turbidity and total petroleum hydrocarbons were monitored and analyzed for 25 months. Results are presented in detail showing significantly smaller amounts of outflow pollutants in SUDS than in conventional drainage systems, especially in the filter drain which provided the best performance.