Angel Vega-Zamanillo

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.

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...

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.

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.

Relationship between Urban Runoff Pollutant and Catchment Characteristics

Much research has been done to determine levels of contamination in runoff from urban and rural catchment areas. Some authors compare their results with other authors or look for relationships between the variations of pollutant concentration and the catchment characteristics, but they seldom focus on determining the statistical significance of their results. This paper presents a review of 37 papers selected from a total of 169 papers consulted about runoff-water quality throughout the world (America, Asia, and Europe). The results presented in these 37 papers have been reviewed and statistically analyzed to evaluate the influence of catchment-area characteristics (location, size, average daily traffic, and type of land use) on the storm water runoff pollution. For the cases studied, most of the results about the polluting agents studied are comparable and no important element of the catchment characteristics had significant influence on the pollutants’ concentration.

Laboratory analysis of a system for catchment, pre-treatment and treatment (SCPT) of runoff from impervious pavements.

This article reports the development and construction of a 1:1 scale laboratory prototype of a System for Catchment, Pre-treatment and Treatment (SCPT) of runoff polluted by contaminants washed from impervious pavements. The concept of the SCPT is an online system with an up-flow filter. The filter is composed of geotextile layers and limestone. The laboratory tests carried out were focused on determining the SCPT prototype behaviour under different working conditions. The variables studied were: inflow, pollutant loads and filtration system configuration. The results show that the system designed has a high capacity for treatment of solids and oil, with an average efficiency of 85% and 97% respectively. Moreover, the regression equations of the treatment efficiency were determined for each of the pollutants studied, for different inflow conditions and pollution loads.

EXPERIMENTAL STUDY OF BITUMINOUS MASTIC BEHAVIOUR USING DIFFERENT FILLERS BASED ON THE UCL METHOD

Abstract This research demonstrates that the use of suitable amounts of calcium hydroxide as an additive in asphalt mixtures can improve the aggregate-bitumen adhesion, forming a bituminous mixture which is more resistant to traffic loads and the action of water. The analysis was performed using the UCL method and the Cantabrian Test, taking as a case study three types of filler with different natures, mixed with 4.5% bitumen. The results are presented as state curves, which show clear differences between the three fillers, demonstrating that the hydroxide suffers small wear losses in concentrations close to 1.3%, indicating a significant reduction in the risk of plastic deformation, and an improvement in the mixture durability and/or adhesiveness.

THERMAL ANALYSIS OF GEOSYNTHETICS USED IN THE REHABILITATION OF PAVEMENTS

Resumen es: El crecimiento de la utilizacion de los geosinteticos en la rehabilitacion de pavimentos flexibles se ha visto incrementado de forma considerable desde l...

ANÁLISIS TÉRMICO DE GEOSINTÉTICOS UTILIZADOS EN LA REHABILITACIÓN DE PAVIMENTOS

Resumen es: El crecimiento de la utilizacion de los geosinteticos en la rehabilitacion de pavimentos flexibles se ha visto incrementado de forma considerable desde l...