For complex geometries, the definition of the subsystems is not a straightforward task. We present here a subsystem identification method based on the direct transfer matrix, which represents the first-order paths. The key ingredient is a cluster analysis of the rows of the powers of the transfer matrix. These powers represent high-order paths in the system and are more affected than low-order paths by damping.
Once subsystems are identified, the proposed approach also provides a quantification of the degree of coupling between subsystems. This information is relevant to decide whether a subsystem may be analysed in a computer model or measured in the laboratory independently of the rest or subsystems or not. The two features (subsystem identification and quantification of the degree of coupling) are illustrated by means of numerical examples: plates coupled by means of springs and rooms connected by means of a cavity.
Corada, M.; Candela, L.; Torres-Fuentes, N.; Pintado-Herrera, M.; Paniw, M.; González-Mazo, E. Science of the total environment Vol. 605-606, p. 770-783 DOI: 10.1016/j.scitotenv.2017.06.049 Data de publicació: 2017-12 Article en revista
This study is focused on the Guadalete River basin (SW, Spain), where extreme weather conditions have become common, with and alternation between periods of drought and extreme rainfall events. Combined sewer overflows (CSOs) occur when heavy rainfall events exceed the capacity of the wastewater treatment plants (WWTP), as well as pollution episodes in parts of the basin due to uncontrolled sewage spills and the use of reclaimed water and sludge from the local WWTP. The sampling was carried out along two seasons and three campaigns during dry (March 2007) and extreme rainfall (April and December 2010) in the Guadalete River, alluvial aquifer and Jerez de la Frontera aquifer. Results showed minimum concentrations for synthetic surfactants in groundwater (< 37.4 µg·L- 1) during the first campaign (dry weather conditions), whereas groundwater contaminants increased in December 2010 as the heavy rainfall caused the river to overflow. In surface water, surfactant concentrations showed similar trends to groundwater observations. In addition to surfactants, pharmaceuticals and personal care products (PPCPs) were analyzed in the third campaign, 22 of which were detected in surface waters. Two fragrances (OTNE and galaxolide) and one analgesic/anti-inflammatory (ibuprofen) were the most abundant PPCPs (up to 6540, 2748 and 1747 ng·L- 1, respectively). Regarding groundwater, most PPCPs were detected in Jerez de la Frontera aquifer, where a synthetic fragrance (OTNE) was predominant (up to 1285 ng·L- 1).
An integral mechanistic model describing the complex interactions in mixed algal-bacterial systems was developed. The model includes crucial physical, chemical and biokinetic processes of microalgae as well as bacteria in wastewater. Carbon-limited microalgae and autotrophic bacteria growth, light attenuation, photorespiration, temperature and pH dependency are some of the new features included. The model named BIO_ALGAE was built using the general formulation and structure of activated sludge models (ASM), and it was implemented in COMSOL Multiphysics™ platform. Calibration and validation were conducted with experimental data from two identical pilot HRAPs receiving real wastewater. The model was able to simulate the dynamics of different components in the ponds, and to predict the relative proportion of microalgae (58–68% in average of total suspended solids (TSS) and bacteria (30–20% in average of TSS). Microalgae growth resulted strongly influenced by the light factor fL(I), decreasing microalgae concentrations from 40 to 60%. Furthermore, reducing the influent organic matter concentration of 50% and 70%, model predictions indicated that microalgae production increased from (8.7 g TSS m- 2d- 1 to 13.5 g TSS m- 2d- 1) due to the new distribution of particulate components. The proposed model could be an efficient tool for industry to predict the production of microalgae, as well as to design and optimize HRAPs.
Nadal, A.; Alamús, R.; Pipia, L.; Ruiz , A.; Corbera, J.; Cuerva, E.; Rieradevall, J.; Josa, A. Science of the total environment Vol. 601-602, p. 1-15 DOI: 10.1016/j.scitotenv.2017.03.214 Data de publicació: 2017-12-01 Article en revista
The integration of rooftop greenhouses (RTGs) in urban buildings is a practice that is becoming increasingly important in the world for their contribution to food security and sustainable development. However, the supply of tools and procedures to facilitate their implementation at the city scale is limited and laborious. This work aims to develop a specific and automated methodology for identifying the feasibility of implementation of rooftop greenhouses in non-residential urban areas, using airborne sensors. The use of Light Detection and Ranging (LIDAR) and Long Wave Infrared (LWIR) data and the Leica ALS50-II and TASI-600 sensors allow for the identification of some building roof parameters (area, slope, materials, and solar radiation) to determine the potential for constructing a RTG. This development represents an improvement in time and accuracy with respect to previous methodology, where all the relevant information must be acquired manually.
The methodology has been applied and validated in a case study corresponding to a non-residential urban area in the industrial municipality of Rubí, Barcelona (Spain). Based on this practical application, an area of 36,312 m2 out of a total area of 1,243,540 m2 of roofs with ideal characteristics for the construction of RTGs was identified. This area can produce approximately 600 tons of tomatoes per year, which represents the average yearly consumption for about 50% of Rubí total population.
The use of this methodology also facilitates the decision making process in urban agriculture, allowing a quick identification of optimal surfaces for the future implementation of urban agriculture in housing. It also opens new avenues for the use of airborne technology in environmental topics in cities.
In this paper, the flexural response of extruded wrought aluminium girders is presented. This structural element is intended for usage in marine structures such as light docks, marinas and yacht ports. Ease of use, durability, reduced weight, manoeuvrability and the potential development of bespoke sections are appealing properties in such structures that are fulfilled satisfactorily by this type of aluminium elements. Both experimental and numerical analyses are presented. Experimentally, modules of the girders are tested with loading about both minor and major axes. Numerically, the tests are satisfactorily reproduced for the sake of validation and a subsequent exploitation of the model is addressed for further study of the structural response of the girders. A discussion of the results is presented with some design recommendations of these particular structural elements.
This paper presents a comprehensive study on the application of global plastic design methods, not currently allowed in European specification provisions, to stainless steel rectangular and square hollow section continuous beams. The analysis of experimental and numerical continuous beam strengths highlighted that ultimate capacity predictions calculated based on global elastic analysis result in a considerable conservatism due to strain hardening and bending moment redistribution effects. Alternatively, the assessment and reliability analyses of the traditional plastic design methods demonstrated that the Class 1 cross-section limit provided in the European specification can be safely applied for the partial safety factor ¿M0 currently provided. However, the analysis evidenced that including bending moment redistribution in capacity predictions is not enough since strain hardening effects play an important role when stocky cross-sections are analysed. Thus, the Continuous Strength Method for indeterminate structures was also assessed and it was found to provide accurate capacity predictions for all analysed stainless steel grades. Finally, an alternative Direct Strength Method design approach is proposed for stainless steel continuous beams based on the Direct Strength Method bending capacity. The proposed method, statistically validated, accounts for strain hardening effects and moment redistribution and provides the best resistance predictions among the different design methods considered
This article presents a mechanical formulation to estimate the strength of transversally stiffened steel plate girders subjected to patch loading, in this particular case, with closely space stiffeners. Steel plate girders with closely spaced stiffeners are occasionally found in bridge design and for such cases, the current EN1993-1-5 rules underestimate the strength of the webs to transverse forces. A FE-based parametric investigation is conducted to estimate the web strength to patch loading. The results are compared to the results obtained from classical beam theory in combination with the proposed formulation. A notional plate girder is analyzed to demonstrate the potential of the formulation for daily routine designs. Results indicate that the proposed formulation does a better job in predicting the web strength of transversely stiffened girders subjected to patch loading than the EN1993-1-5 specification, and thus yield a lighter and more economical design for these specific girder geometries.
The behaviour of austenitic, ferritic and duplex stainless steel Rectangular and Square Hollow Section members subjected to compression and combined loading is investigated in this paper. A full slenderness range Direct Strength Method (DSM) approach is proposed based on experimental results and numerical strengths obtained from FE parametric studies. The method accounts for local buckling effects and enhanced material properties are also incorporated for those members stable enough to allow partial yielding of the cross-sections. The proposed method is based on strength curves previously provided for cross-sections although additional limitations have been adopted. The DSM approach for columns is based on existing buckling curves and provides accurate resistance predictions for slender and stocky cross-sections. The proposed DSM approach for beam-columns also improves capacity predictions for stocky and slender cross-sections obtained from the traditional methods for different bending moment distributions. This is attributed to the fact that the beam-column behaviour is directly calculated with a unique strength curve, considering the member and section slendernesses based on the elastic instabilities of the section subjected to the actual stress distribution instead of calculating the compressive and flexural strengths independently and combining these through an interaction equation, as is the traditional uncoupled approach. Finally, a reliability study of the full slenderness range DSM approach is presented to determine resistance factors for the different stainless steel grades columns and beam-columns
Submarine groundwater discharge (SGD) has been recognized as an important supplier of chemical compounds to the ocean that may influence coastal geochemical cycles. Radium isotopes (223Ra, 224Ra, 226Ra,228Ra) and radon (222Rn) have been widely applied as tracers of SGD. Their application requires the appropriate characterization of both the concentrations of tracers in the discharging groundwater and their distribution in the coastal water column. This study evaluates the temporal evolution of Ra isotopes and 222Rn concentrations in a dynamic subterranean estuary of a microtidal Mediterranean coastal aquifer that experiences large displacements of the fresh-saltwater interface as a necessary initial step in evaluating the influence of SGD in coastal waters. We show that changes in groundwater salinities due to the seaward displacement of the fresh-saltwater interface produced large variations in Ra activities in groundwater (by a factor of ~ 19, ~ 14, ~ 6, and ~ 11 for 223Ra, 224Ra, 226Ra and 228Ra, respectively), most importantly during rainfall events. In contrast, the 222Rn activities in groundwater oscillated only by a factor of 3 during these rainy periods. The large temporal variability in Ra activities hampers the characterization of the SGD end-member when using Ra isotopes as tracers, and thus presents a challenge for obtaining accurate SGD estimates. This study emphasizes the need to understand the hydrodynamics of coastal aquifers to appropriately constrain the Ra isotopes and 222Rn concentrations in groundwater and when applying both tracers in dynamic microtidal coastal systems.
López, R.; Pujadas, P.; Pialarissi Cavalaro, S.H.; Aguado, A. Construction & building materials Vol. 153, p. 835-845 DOI: 10.1016/j.conbuildmat.2017.07.136 Data de publicació: 2017-10 Article en revista
A bonded concrete overlay consists of a concrete layer poured over a deteriorated pavement. Its mechanical performance depends on the quality of the bond between the lower and the uppermost layers. This paper reports an extensive experimental program to evaluate bond strength between Conventional Concrete (CC) and Asphalt Concrete (AC) substrates and Self-Compacting High-Performance Concrete (SCHPC) overlays. In all, 8 interface treatments are tested under Direct Tension, pure shear “LCB”, and compressive Slant Shear tests. The results show that direct pouring of the SCHPC overlay over CC and AC substrates produces similar or higher strengths than the other treatments analyzed.
The accuracy of bridge system safety evaluations and reliability assessments obtained through refined structural analysis procedures depends on the proper modeling of traffic load effects. While the live-load models specified in AASHTO procedures were calibrated for use in combination with approximate analysis methods and load-distribution factors commonly used in the United States, these existing models may not produce accurate results when used in association with advanced finite-element analyses of bridge structures. This paper proposes a procedure for calibrating appropriate live-load models that can be used for advanced analyses of multigirder bridges. The calibration procedure is demonstrated using actual truck data collected at a representative set of weigh-in-motion (WIM) stations in New York State. Extreme value theory was used to project traffic-load effects to different service periods. The results are presented as live-load models developed for a 5-year typical rating interval and for a 75-year design life. The outcome of the calibration indicates that maximum traffic-load effects can be calculated using finite-element models with the help of a single truck for short to medium one-lane multigirder bridges and two side-by-side truck configurations for multilane bridges. The proposed analysis trucks have axle configurations of the standard AASHTO 3-S2 and Type 3 legal rating trucks with appropriate factors to amplify their nominal weights. The amplification factors reflected the presence of overweight trucks in the traffic stream and the probability of multiple presence. The proposed live-load models are readily implementable for deterministic refined analyses of highway bridges and for evaluating the reliability of bridges at ultimate limit states considering the system’s behavior.
This book brings together some 20 chapters on state-of-the-art research in the broad field of computational plasticity with applications in civil and mechanical engineering, metal forming processes, geomechanics, nonlinear structural analysis, composites, biomechanics and multi-scale analysis of materials, among others. The chapters are written by world leaders in the different fields of computational plasticity.
Petracca, M.; Pelà, L.; Rossi, R.; Zaghi, S.; Camata, G.; Spacone, E. Construction & building materials Vol. 149, p. 296-314 DOI: 10.1016/j.conbuildmat.2017.05.130 Data de publicació: 2017-09 Article en revista
A novel damage mechanics-based continuous micro-model for the analysis of masonry-walls is presented and compared with other two well-known discrete micro-models. The discrete micro-models discretize masonry micro-structure with nonlinear interfaces for mortar-joints, and continuum elements for units. The proposed continuous micro-model discretizes both units and mortar-joints with continuum elements, making use of a tension/compression damage model, here refined to properly reproduce the nonlinear response under shear and to control the dilatancy. The three investigated models are validated against experimental results. They all prove to be similarly effective, with the proposed model being less time-consuming, due to the efficient format of the damage model. Critical issues for these types of micro-models are analysed carefully, such as the accuracy in predicting the failure load and collapse mechanism, the computational efficiency and the level of approximation given by a 2D plane-stress assumption.
A vehicle exposed to flooding, after losing stability, becomes buoyant and may be washed away with potential injuries and fatalities. Such vehicles cause additional disruption to traffic that is already affected by flooding, which may lead to substantial indirect economic impact, especially in urban areas. Therefore, the analysis of the stability of vehicles exposed to flooding is important in order to make decisions to reduce damages and hazards. In this research, based on an experimental campaign that included a range of twelve car models, a new methodology to obtain the stability threshold for any real vehicle exposed to flooding is developed. A stability coefficient (SCmod) is derived with which the vehicles can be sorted by stability against water flows and their stability functions may be determined. The experiments were conducted with three different model scales (1:14, 1:18 and 1:24) and involved analysis of both friction and buoyancy effects, which made this the most comprehensive research study to date. This methodology enables the definition of a stable area in the flow depth-velocity domain for any real vehicle. A tool is provided that decision-makers in the field of urban flood risk management can employ and after defining a design vehicle they can obtain its corresponding stability threshold.
The Temple of Sagrada Familia presents singularities in terms of both the original design by architect Antoni Gaudí and the duration
of the construction, which started more than 120 years ago. In fact, its design was conceived before the development of reinforced concrete. Therefore, the construction materials and processes have evolved to adapt new technologies without compromising the vision of Gaudí. This willingness to maintain the original designs has obliged the technicians to resolve details that were not defined in the project, including the issue of how to cast elements at great heights and with a high amount of reinforcement. In this context, the possibility of using self-compacting concrete (SCC) emerged. This paper describes the different experiences in the Temple of Sagrada Familia with SCC, from requirements that led to using this material to the design of the mixes and the casting of the elements in situ.
The potential impacts of tsunamis along the Catalan Coast (NW Mediterranean) are analysed using numerical modelling. The region is characterized by moderate to low seismic activity and by moderate- to low-magnitude earthquakes. However, the occurrence of historical strong earthquakes and the location of several active offshore faults in front of the coast suggest that the possibility of an earthquake-triggered tsunami is not negligible although of low probability. Up to five faults have been identified to generate tsunamis, being the highest associated possible seismic magnitudes of up to 7.6. Coastal flooding and port agitation are characterized using the Worst-case Credible Tsunami Scenario Analysis approach. The results show a multiple fault source contribution to tsunami hazard. The shelf dimensions and the existence of submerged canyons control the tsunami propagation. In wide shelves, waves travelling offshore may become trapped by refraction causing the wave energy to reach the coastline at some distance from the origin. The free surface water elevation increases at the head of the canyons due to the sharp depth gradients. The effects of potential tsunamis would be very harmful in low-lying coastal stretches, such as deltas, with a high population concentration, assets and infrastructures. The Ebro delta appears to be the most exposed coast, and about the 20% of the delta surface is prone to flooding due to its extremely low-lying nature. The activity at Barcelona port will be severely affected by inflow backflow current at the entrance of up to 2 m/s.
Pujadas, P.; Blanco, A.; Pialarissi Cavalaro, S.H.; de la Fuente, A.; Aguado, A. Construction & building materials Vol. 149, num. 15, p. 790-800 DOI: 10.1016/j.conbuildmat.2017.05.166 Data de publicació: 2017-09 Article en revista
The flexural creep of plastic fiber reinforced concrete (PFRC) is a controversial issue since significant doubts regarding the suitability of this type of fiber and its influence in the long-term behavior of the material still exist. The objective of this paper is to evaluate the post-cracking creep response of PFRC beams under flexural load in comparison with that of steel fiber reinforced concrete (SFRC) beams. The aim is to explore how the pre-crack opening and the environmental condition affect the long term behavior of each material and identify differences. An experimental program was conducted with 30 concrete beams with dimension of 150 × 150 × 600 mm reinforced with plastic or steel fibers subjected to a 4-point bending creep test for 5 months under 2 environmental conditions. Results showed that the flexural creep coefficient of PFRC is 2 times bigger than that of SFRC. Despite that, the use of plastic fibers as reinforcement should not be rejected as long as the additional creep is considered in the design and the crack widths are limited to reduce the risk of tertiary creep.
Escudero-Torres, C.; Oller, S.; Martinez, X.; Barbat, A. H. Journal of engineering mechanics Vol. 143, num. 9, p. 04017080-1-04017080-19 DOI: 10.1061/(ASCE)EM.1943-7889.0001275 Data de publicació: 2017-09 Article en revista
The construction of confined masonry buildings has become a good choice to meet the housing needs of low-income families inbig cities. Despite this, current building codes for such construction allow the use of highly simplified analysis techniques that have hardlychanged in the last 40 years. This paper is based on numerical simulation and discusses the need to combine and improve existing techniquesin finite-element method (FEM) analysis for composite materials, to assess the overall structural behavior of reinforced concrete structureswith masonry in-fills, and consequently to support the derivation of rational rules for analysis and design. Through the use of a simpleyet powerful shell finite element (FE), state-of-the-art theories of mixtures to analyze composite materials, a computational tool to generatethe volume fraction of composites, and the Mexican building code, this paper attempts to be a guide to numerical reproduction ofthe overall behavior of confined masonry structures.
The aim of this study was to assess the environmental impact of three alternatives for wastewater treatment in small communities. To this end, a Life Cycle Assessment (LCA) was carried out comparing a conventional wastewater treatment plant (i.e. activated sludge system) with two nature-based technologies (i.e. hybrid constructed wetland and high rate algal pond systems). Moreover, an economic evaluation was also addressed. All systems served a population equivalent of 1500 p.e. The functional unit was 1 m3 of water. System boundaries comprised input and output flows of material and energy resources for system construction and operation. The LCA was performed with the software SimaPro® 8, using the ReCiPe midpoint method. The results showed that the nature-based solutions were the most environmentally friendly alternatives, while the conventional wastewater treatment plant presented the worst results due to the high electricity and chemicals consumption. Specifically, the potential environmental impact of the conventional wastewater treatment plant was between 2 and 5 times higher than that generated by the nature-based systems depending on the impact category. Even though constructed wetland and high rate algal pond systems presented similar results in terms of environmental impact, the latter showed to be the less expensive alternative. Nevertheless, the constructed wetland system should be preferred when land occupation is of major concern, since it has a smaller footprint compared to the high rate algal pond alternative.
Mujal -Colilles, A.; Gironella, X.; Crespo, A. J. C.; Sanchez-Arcilla, A. Journal of waterway, port, coastal, and ocean engineering Vol. 143, num. 5, p. 1-8 DOI: 10.1061/(ASCE)WW.1943-5460.0000382 Data de publicació: 2017-09 Article en revista
Twin propellers without a rudder were studied using a physical model with a fixed clearance distance and three different rotating velocities. Experimental results were compared with results from theoretical expressions developed over the past 50 years for the efflux velocity, axial velocity, and maximum bed velocity. It was found that the efflux velocity equations overestimated the experimental results, whereas the computed axial velocities matched the experimental data reasonably well. However, when maximum bed velocity expressions were compared with experimental results, only one method was found to behave better; overestimation resulted if a quadratic superposition of single jets was used.
Eskicioglua, C.; Monlau, F.; Barakat, A.; Ferrer, I.; Kaparaju, P.; Trably, E.; Carrère, H. Water Research Vol. 120, p. 32-42 DOI: 10.1016/j.watres.2017.04.068 Data de publicació: 2017-09 Article en revista
Hydrothermal pretreatment of five lignocellulosic substrates (i.e. wheat straw, rice straw, biomass sorghum, corn stover and Douglas fir bark) were conducted in the presence of CO2 as a catalyst. To maximize disintegration and conversion into bioenergy (methane and hydrogen), pretreatment temperatures and subsequent pressures varied with a range of 26–175 °C, and 25–102 bars, respectively. Among lignin, cellulose and hemicelluloses, hydrothermal pretreatment caused the highest reduction (23–42%) in hemicelluloses while delignification was limited to only 0–12%. These reductions in structural integrity resulted in 20–30% faster hydrolysis rates during anaerobic digestion for the pretreated substrates of straws, sorghum, and corn stover while Douglas fir bark yielded 172% faster hydrolysis/digestion due to its highly refractory nature in the control. Furans and phenolic compounds formed in the pretreated hydrolyzates were below the inhibitory levels for methane and hydrogen production which had a range of 98–340 ml CH4/g volatile solids (VS) and 5–26 ml H2/g VS, respectively. Results indicated that hydrothermal pretreatment is able to accelerate the rate of biodegradation without generating high levels of inhibitory compounds while showing no discernible effect on ultimate biodegradation.
Blanco, A.; Aire, C.; Pujadas, P.; Pialarissi Cavalaro, S.H. Construction & building materials Vol. 149, p. 207-217 DOI: 10.1016/j.conbuildmat.2017.05.135 Data de publicació: 2017-09 Article en revista
The behavior of concrete subjected to shear can be significantly improved by the addition of fibers, which may partially or totally substitute the traditional steel stirrups (also known as links). Design recommendations include formulations to account for the contribution of the fibers. However, these formulations take the results of small-scale bending tests as input parameters. The main reason for that is the lack of standardized tests and the difficulty to assess direct shear in fiber reinforced concrete (FRC) both for the design and for the quality control. The present study proposes a test for the characterization of the post-cracking shear response of FRC. The test is validated through an experimental program with conventional concrete and FRC. The influence of different parameters (geometry of the specimen, the type and the content of fiber) is assessed and a comparison is made between the push-off test and the one proposed here. Results of an in-depth statistical analysis indicate that the latter is a simpler and valid alternative to evaluate the post-cracking shear response of FRC.
Etxeberria, M.; Ming-Zhi, G.; Maury-Ramirez, A.; Poon, C. Journal of Environmental Engineering Vol. 143, num. 9, p. 1-10 DOI: 10.1061/(ASCE)EE.1943-7870.0001239 Data de publicació: 2017-09 Article en revista
The day-to-day negative effect of contaminating substances on the NOx removal effectiveness of photocatalytic surfaces and their recovery capacity after undergoing cleansing is of real academic and practical interest. This paper analyzes the NOx removal effectiveness of two different types of photocatalytic concrete surface layers incorporating nano-TiO2 particles. Both types of surfaces are examined before and after being subjected to dust accumulation and oil impregnation. The recovery of their NOx removal capacity after undergoing various cleansing processes is also evaluated. The results are compared to those of their respective reference samples. The results show that the high NOx removal capacity of the spray-coated samples is partially maintained even after a high concentration of dust accumulation. However,
the water-cleansing process employed is sufficient to recover the lost NOx removal capacity. It is also discovered that the nano-TiO2 particles lose nearly all their photocatalytic capacity after being subjected to oil impregnation, and that the cleansing processes, either by an alkaline detergent or using an n-hexane solvent, fails to recover the initial NOx removal capacity.
Harbours are essential infrastructures for economic activity that are susceptible to impacts from climate change driven processes, like sea level rise (SLR), or alterations in wave patterns. In this paper, the impact of climate change on wave agitation in ports (oscillations due to wind waves) and, therefore, on port operability is analyzed. This is carried out through a numerical model suite, considering the RCP8.5 scenario to project changes in wave fields, and three values of SLR. The study is particularized for the port of Barcelona (NW Mediterranean), but the used methodology can be applied to other harbours. Results suggest that changes due only to waves will be minimal and with a general trend to slightly decrease wave agitation. On the contrary, the effect of SLR and the associated increase of water depth will favor the penetration of waves within the harbour, leading to a certain reduction of port operability, the magnitude of which will depend on the SLR value. However, the complexity of wave patterns within the harbours, due to multiple reflections of waves on port structures, implies that the reduction of operability strongly varies according to the position and orientation of the berthing zones inside the harbour.
Petit-Boix, A.; Sevigné-Itoiz, E.; Rojas-Gutierrez, L.; Paceli, A.; Josa, A.; Rieradevall, J.; Gabarrell, X. Journal of cleaner production Vol. 162, p. 601-608 DOI: 10.1016/j.jclepro.2017.06.047 Data de publicació: 2017-09 Article en revista
Stormwater management is essential to reducing the occurrence of flooding events in urban areas and to adapting to climate change. The construction of stormwater Best Management Practices (BMPs) entails a series of life cycle environmental impacts but also implies avoided burdens, such as replacing urban infrastructure after flooding. The aim of this paper is to integrate flood damage prevention into the life cycle assessment (LCA) of BMPs for quantifying their net environmental impact (NEI) and environmental payback (EP) from a consequential LCA standpoint. As a case study, the application of a filter, swale and infiltration trench (FST) in a Brazilian neighborhood was assessed considering a high-intensity rainfall event. The potential avoided impacts were related to cars and sidewalks that were not destroyed due to flooding. In terms of CO2eq. emissions, the environmental investment related to the FST was recovered when the destruction of one car or 84 m2 of sidewalk was prevented. The NEI of the FSTs resulted in significant impact reductions (up to 700%) with respect to not accounting for the avoided products. This approach can be implemented to any type of BMP, and more accurate estimations can be made with data for different events and different types of material damage.
Near-surface radar reflectivity observations meet the requirements of flash floods detection and forecasting, thanks to their capability to capture the short-term evolution of the rainfall field at high temporal and spatial resolution. Also, the improvements in national and transnational operational radar networks provide improved rainfall observations and rainfall nowcasting that can help identifying and anticipating the areas potentially affected by the hazards associated to heavy rains.
We present flash flood events occurred in Europe during 2015-2017 and identified by the real-time flash flood module of the European Rainfall-InduCed Hazard Assessment (ERICHA) system (and recently implemented in the European Flood Awareness System, EFAS). This flash-flood forecasting module is based on the rainfall inputs from the European radar reflectivity composites generated by the EUMETNET project OPERA (Operational Programme for the Exchange of weather RAdar) with resolutions of 2 km, 15 minutes.
Because the performance of the tool is critically affected by the quality of the radar quantitative precipitation estimates (QPE), the presentation will focus on the status of radar QPE using raingauge measurements throughout Europe. The impact of the QPE to the hazard identification and assessment will be illustrated through the selected events.
Attenuation due to liquid water is one of the largest uncertainties in radar observations. The magnitude of attenuation is generally inversely proportional to the wavelength, i.e. observations from X-band radars are more affected by attenuation than those from C- and S-band systems. On the other hand, X-band radars can provide precipitation fields in higher temporal and spatial resolution and are more mobile and easier to install due to smaller antennas. Dual-polarization can be used to estimate attenuation but those systems are much more expensive than single-polarized radars.
Hitschfeld and Bordan (1954) proposed an algorithm for attenuation correction in single-polarized system but it gets unstable in case of strong attenuation. Therefore, methods have been developed that restrict attenuation correction to keep the algorithm stable, using e.g. surface echo (for space borne radars) and mountain returns (for ground radars) or adjustment of the radar constant. All these methods are based on the statistical relation between reflectivity and specific attenuation. Another way to correct for attenuation in X-band radar observations, is to use additional information from less attenuated radar systems, e.g. the ratio between X-band and C- or S-band radar measurements.
We will present a comparison of the original HB algorithm and three algorithms based on the statistical relation between reflectivity and specific attenuation as well as two methods implementing C-band radar measurements. Their performance in a convective and in a stratiform precipitation event will be investigated. Furthermore, a study of five month of radar observations examines the long-term performance of each algorithm.
Hitschfeld, W. and Bordan, J.: Errors Inherent in the Radar Measurement of Rainfall at Attenuating Wavelengths, J. Meteorol., 11, 58--67, 1954
The existing methods for radar-rain gauge blending use direct rain gauge observations and detailed spatiotemporal radar measurements to produce Quantitative Precipitation Estimates (QPE). In the last years, many of these methods use kriging techniques to improve these estimates, thanks to the explicit incorporation of rainfall spatial variability characterized by the variogram function.
Velasco-Forero et al. (2009) proposed the use of kriging with external drift (KED) and non-parametric variograms. The technique uses the radar rainfall map as the drift to interpolate rain gauge observations; it also accounts for the anisotropy of the rainfall, since the variograms are two-dimensional; and, most importantly, the variograms are obtained automatically and updated every time new (radar and gauges) rainfall observations are available. As such, the technique proposed produces snapshot estimates that are independent in time.
The work presented here explores the extension of that technique to include the time dimension in the blending process, so that rainfall estimates depend, not only on current observations, but also on past observations. This extension accounts for the correlation in time, and implicitly imposes some coherence between consecutive QPE maps.
The technique has been evaluated for several rainfall events in the area of Barcelona (NE Spain), and compared with the results obtained with the original formulation of the technique, which does not account for correlation in time.
Pérez, D.; Iannone, A.; Martinez, A.; Giustozzi, F. Journal of materials in civil engineering Vol. 29, num. 8, p. 04017058-1-04017058-8 DOI: 10.1061/(ASCE)MT.1943-5533.0001831 Data de publicació: 2017-08 Article en revista
The use of reclaimed asphalt pavement (RAP) in bituminous mixtures is considerably increasing due to the environmental and economic benefits of recycled materials. However, stiffer mixes, usually resulting from RAP addition, have raised concern about long-term properties of the pavement; a mechanical characterization of these mixes is thus needed. In this study, the effect of mixing condition on bituminous mixtures containing RAP was evaluated. Volumetric and mechanical properties were analyzed. An experimental program, with the aim of measuring stiffness modulus, water sensitivity, and cracking resistance, was conducted. Cracking resistance was evaluated according to the Fénix test because it has proved to be a convenient and effective method for characterizing cracking behavior of bituminous mixtures at different temperatures. Mixtures containing 20 or 40% of RAP material were tested; virgin aggregates and RAP mixing temperatures as well as mixing time were varied and comparisons with a reference mix were conducted to characterize fracture energy and mechanical performance.
The Equivalent-Frame Method (EFM), a simplified procedure for structural modelling of masonry constructions, is having a great success for the good balance that it allows between the accuracy of the geometrical description and the simplicity of the mechanical calibration.
Despite the widespread use of EFM in scientific and professional field, some uncertainties affect its application to the specific problem of the existing unreinforced masonry (URM) buildings. For these structures, in fact, irregular geometries, the presence of deformable diaphragms and the interaction with other structures in aggregate configurations represent hard-to-model features that limit the accuracy of EFM.
The paper presents a comparative study in the linear field between EFM and the more accurate Finite Element Method (FEM), assumed as reference. The comparative analysis involves a wide set of geometrical schemes, characterized by both regular and irregular configurations, and it is aimed at providing a measure of the EFM modelling accuracy as a function of the geometry of the wall. Non-dimensional parameters allow exploring the limits of applicability of EFM for both regular and irregular walls.
Based on the parametric analyses, some recommendations are given for improving the effectiveness of the method and preserving the simplicity of application that makes EFM models so popular and widely used.
Garcia, R.; Borzacchiello, D.; Chinesta, F.; Diez, P. International journal for numerical methods in engineering Vol. 111, num. 6, p. 529-552 DOI: 10.1002/nme.5470 Data de publicació: 2017-08 Article en revista
The parametric analysis of electric grids requires carrying out a large number of Power Flow computations. The different parameters describe loading conditions and grid properties. In this framework, the Proper Generalized Decomposition (PGD) provides a numerical solution explicitly accounting for the parametric dependence. Once the PGD solution is available, exploring the multidimensional parametric space is computationally inexpensive. The aim of this paper is to provide tools to monitor the error associated with this significant computational gain and to guarantee the quality of the PGD solution. In this case, the PGD algorithm consists in three nested loops that correspond to 1) iterating algebraic solver, 2) number of terms in the separable greedy expansion and 3) the alternated directions for each term. In the proposed approach, the three loops are controlled by stopping criteria based on residual goal-oriented error estimates. This allows one for using only the computational resources necessary to achieve the accuracy prescribed by the end- user. The paper discusses how to compute the goal-oriented error estimates. This requires linearizing the error equation and the Quantity of Interest to derive an efficient error representation based on an adjoint problem. The efficiency of the proposed approach is demonstrated on benchmark problems.
Castro Alves Oliveira, T.; Sanchez-Arcilla, A.; Gironella, X.; Madsen, O. S. Journal of hydraulic research Vol. 55, num. 4, p. 538-556 DOI: 10.1080/00221686.2016.1275047 Data de publicació: 2017-08 Article en revista
Most of the coastal hydraulic studies in physical and numerical wave flumes (NWF) require the correct generation of nonlinear, long period waves at intermediate and shallow water conditions. In this paper, the ability to generate such long waves in an NWF based on the particle finite element method (PFEM) is analysed. Wavemaker theories based on the Stokes second-order wave theory, cnoidal wave theory and solitary wave theory are implemented in the NWF through piston type paddle boundary conditions. An assessment of the capability and robustness of generation and propagation of long waves in the NWF is carried out. Numerical results are compared to theoretical results and the data from physical tests. Results indicate that regular long waves of permanent form can be generated in an NWF based on the PFEM using the implemented wavemaker theories. However, when choosing a wavemaker theory a compromise has to be made between the target wave conditions and the validity range of each wavemaker theory.
The potential ecotoxicological effects of mixtures of contaminants in the aquatic environment are generating a global concern. Benthic invertebrates, such as the crustacean Gammarus fossarum, are key in the functioning of aquatic ecosystems, and are frequently used as sentinel species of water quality status. The aim of this work was to study the effects of a mixture of the most frequently detected surfactants in the bioconcentration kinetics of two pharmaceuticals in G. fossarum, evaluating their potential enhancing or suppressing effects. Laboratory exposure experiments for both pharmaceuticals and surfactants (concentration ratio 1:25) were set up for two individual compounds, the anxiolytic oxazepam and the antibiotic sulfamethoxazole. Gammarid samples were processed using microQuEChERS (Quick, Easy, Cheap, Effective, Rugged, and Safe) extraction. Pharmaceuticals concentration in the organisms was followed-up by means of nanoliquid chromatography coupled to tandem mass spectrometry (nanoLC-MS/MS). Results indicated a similar mode of action of the surfactants in the bioconcentration kinetics of both drugs, decreasing the accumulation rate in the organism. Oxazepam showed a higher accumulation potential than sulfamethoxazole in all cases. Depuration experiments for oxazepam also demonstrated the high depurative capacity of gammarids, eliminating > 50% of the concentration of oxazepam in < 6 h.
This work presents a general formulation and implementation in solid-shell elements of the refined zigzag theory and the trigonometric shear deformation theory in an unified way. The model thus conceived is aimed for use in the analysis, design and verification of structures made of composite materials, in which shear strains have a significant prevalence. The refined zigzag theory can deal with composite laminates economically, adding only two nodal degrees of freedom, with very good accuracy. It assumes that the in-plane displacements have a piece-wise linear shape across the thickness depending on the shear stiffness of each composite layer. The trigonometric theory assumes a cosine variation of the transverse shear strain. A modification of this theory is presented in this paper allowing its implementation with C0 approximation functions. Two existing elements are considered, an eight-node tri-linear hexahedron and a six-node triangular prism. Both elements use a modified right Cauchy-Green deformation tensor View the MathML source where five of its six components are linearly interpolated from values computed at the top and bottom surfaces of the element. The sixth component is computed at the element center and it is enhanced with an additional degree of freedom. This basic kinematic is improved with a hierarchical field of in-plane displacements expressed in convective coordinates. The objective of this approach is to have a simple and efficient finite element formulation to analyze composite laminates under large displacements and rotations but small elastic strains. The assumed natural strain technique is used to prevent transverse shear locking. An analytic through-the-thickness integration and one point integration on the shell plane is used requiring hourglass stabilization for the hexahedral element. Several examples are considered on the one hand to compare with analytical static solutions of plates, and on the other hand to observe natural frequencies, buckling loads and the non-linear large displacement behavior in double curved shells. The results obtained are in a very good agreement with the targets used.
This paper presents the necessary conditions to ensure a minimal profitability of carrier-led consolidation strategies in urban distribution. These conditions are shown by compact formulas obtained by continuous approximations representing the cost of the stakeholders involved: society, regular carriers, consolidation facility operator and environment. The domain of the retailer density variable that always produces negative effects on each stakeholder has been identified. The envelope of this domain does not depend on vehicle costs and other site-related parameters. On the other hand, there is a critical density of receivers that makes the carrier cost savings higher than the CF operator costs.
This paper details a semi-analytical procedure to efficiently integrate the product of a smooth function and a complex exponential over tetrahedral elements. These highly oscillatory integrals appear at the core of different numerical techniques. Here, the Partition of Unity Method (PUM) enriched with plane waves is used as motivation. The high computational cost or the lack of accuracy in computing these integrals is a bottleneck for their application to engineering problems of industrial interest. In this integration rule, the non-oscillatory function is expanded into a set of Lagrange polynomials. In addition, Lagrange polynomials are expressed as a linear combination of the appropriate set of monomials, whose product with the complex exponentials is analytically integrated, leading to 16 specific cases that are developed in detail. Finally, we present several numerical examples to assess the accuracy and the computational efficiency of the proposed method, compared to standard Gauss-Legendre quadratures.
A (k,g)-graph is a k-regular graph with girth g and a (k,g)-cage is a (k,g)-graph with the fewest possible number of vertices. The cage problem consists of constructing (k,g)-graphs of minimum order n(k,g). We focus on girth g=5, where cages are known only for degrees k=7. We construct (k,5)-graphs using techniques exposed by Funk (2009) and Abreu et al. (2012) to obtain the best upper bounds on n(k,5) known hitherto. The tables given in the introduction show the improvements obtained with our results.
This study aimed at analyzing the anaerobic co-digestion of microalgal biomass grown in wastewater and wheat straw. To this end, Biochemical Methane Potential (BMP) tests were carried out testing different substrate proportions (20–80, 50–50 and 80–20%, on a volatile solid basis). In order to improve their biodegradability, the co-digestion of both substrates was also evaluated after applying a thermo-alkaline pretreatment (10% CaO at 75 °C for 24 h). The highest synergies in degradation rates were observed by adding at least 50% of wheat straw. Therefore, the co-digestion of 50% microalgae – 50% wheat straw was investigated in mesophilic lab-scale reactors. The results showed that the methane yield was increased by 77% with the co-digestion as compared to microalgae mono-digestion, while the pretreatment only increased the methane yield by 15% compared to the untreated mixture. Thus, the anaerobic co-digestion of microalgae and wheat straw was successful even without applying a thermo-alkaline pretreatment.
This paper proposes an improved theoretical prediction equation for Concrete-filled steel tubes (CFT) subjected to compressive forces. This ultimate load capacity is inferred from a database of 344 experimental results reported in the literature by using Gene expression programming (GEP). Moreover, a series of structural comparisons between design provisions, other mechanically-derived expressions and the proposed prediction are addressed. The levels of accuracy, practical use and phenomenological understanding of the phenomenon are pinpointed. The results obtained are in good agreement with both the experimental and theoretical predictions. Advantages and disadvantages of such type of predictions are pinpointed.
A description of the deformations and damage that occurred in a segmental tunnel lining as a consequence of an unplanned surface load is presented, as well as the numerical analyses performed for its safety assessment. The tunnel in study is located in soft soil conditions and presents a low overburden. Few months after tunnel drilling, a new bridge was constructed at surface level, placing an access embankment over the tunnel path. Monitoring points were installed along the affected section which recorded the deformation of the tunnel caused by the embankment weight. More worryingly, despite no additional loads were introduced, the deformation of the lining continued increasing significantly along the next months, indicating the existence of soil consolidation phenomena. As a consequence, structural cracks emerged along the affected section. Non-linear finite element models that realistically simulate the behaviour of the non-linear segment joints and the concrete cracking were used to characterize the actual response and strength of the lining. The results showed that most significant damages should occur at the non-visible extrados side, and characterized how they evolve along the soil consolidation process. Finally, the adopted tunnel strengthening procedure is described.
In order to make decisions efficiently and equitably, up-to-date information is required. In developing countries, with limited resources, such information should be provided by means of cost-effective methodologies, in which sampling issues are of primary importance. Different sampling strategies are currently in use. At local level with reduced populations, standard approaches prove expensive and time consuming. In this paper, we opt for simple linear piecewise approximations to calculate the sample size in terms of given precision, confidence level and population size. To support the applicability of the proposed approach by practitioners in the field, easy-to-use tables are elaborated. In terms of sampling, easy-to-follow practical guidelines for household selection and transect walk planning are also provided. The article presents six rural communities in Honduras as initial case study to illustrate the validity and applicability of the approach adopted herein for sampling design and sample size determination.
In a complex vibroacoustic system the overall noise or vibration in a given location is the sum of multiple subsystem contributions. From an experimental perspective, the total noise can be directly measured but not the contributions. Methods based in transmissivity measurements, as ATPA, allow to find these contributions experimentally and understand the system behaviour through the path concept. Two different contributions to the ATPA method are included here. On the one hand, a numerical model that simulates a simple vibroacoustic problem is shown. This is a closed cuboid-shaped box with air cavity inside. The ATPA experimental procedure is reproduced numerically in order to gain knowledge on some aspects of the method. On the other hand, a technique for the auto matic identification of the subsystems which is based on the path concept and transfer matrices is applied to the acoustic problem of coupled rooms. The proper definition of subsystems influences very much the reliability of ATPA results.
Las zonas costeras concentran un elevado número de valores tanto naturales como socio-económicos que las hacen muy vulnerables a los efectos potenciales de los riesgos naturales. Por ello, para llevar a cabo una gestión adecuada del riesgo se requiere un análisis holístico en el que se tengan en cuenta las múltiples componentes que determinan el riesgo. Esto se ha abordado con el uso del concepto de El Paisaje del Riesgo Costero, que puede definirse como el riesgo integrado de las zonas costeras del resultado de la acción e interacción de los riesgos naturales y/o humanos inducidos sobre los valores y bienes existentes. La tesis presenta una metodología para la evaluación del riesgo de erosión e inundación costera a escala regional en el que se considera el análisis integrado de los principales procesos asociados a forzamientos que inducen erosión e inundación a diferentes escalas temporales (episódica, medio y largo plazo) así como un análisis de sus consecuencias socio-económicas. Esto se ha enmarcado dentro del modelo Source-Pathway-Receptor-Consequence (SPRC) en el cual el ¿pathway¿ se ha adaptado para representar cada riesgo considerando los diferentes procesos relacionados que actúan a diferentes escalas temporales. Para ello, cada componente (proceso) es evaluada individualmente y clasificada en una escala de intensidad que permite la integración y comparación de su importancia relativa a lo largo de la costa. La escala de intensidad para las componentes de erosión (episódica, medio y largo plazo), se consideran en terminos de como se ve afectada la playa para proveer la funcion de recreación y protección. Para la inundación, se utilizan diferentes variables que permiten caracterizar y evaluar cada una de sus componentes (riadas, inundación marina e inundación por la subida del nivel del mar SNM) clasificandolas en una escala de intensidad. Esto permite la evaluación de la contribución individual así como la relativa al riesgo final. Las consecuencias de erosión e inundación se determinan por separado teniendo en cuenta sus impactos más relevantes. En el caso de erosión, se consideran valores socio-económicos de las dos funciones costeras analizadas. Luego, las componentes de erosión se combinan en una matriz de riesgo, que proporcionan valores del riesgo para diferentes objetivos de gestión costera (i.e. recreación y protección). En el caso de la inundación, las consecuencias se evalúan mediante la caracterización de valores en exposición basados en un indicador que abarca cinco categorías (usos del suelo, población y vulnerabilidad social, sistema de transportes, negocios y servicios públicos). El riesgo total se expresa como la combinación de la amenaza y el valor de exposición. Todo ello es integrado a una escala adecuada de gestión, representada por el municipio. Esta metodología se ha aplicado a 219 km de playas a lo largo de la costa catalana (NE Mediterráneo español). Los resultados obtenidos indican que a pesar del buen estado general de la costa para proveer las funciones de recreación y protección en la actualidad, considerando una proyección futura para el año 2035 con las componentes de erosión a medio y largo plazo (erosión de base+erosión por SLR) el riesgo para proveerla se incrementa sustancialmente. Así, los municipios que en la actualidad tienen un desarrollo basado en el turismo, tendrán problemas para proveer un uso recreativo, y en la comarca del Maresme difícilmente se podrá proporcionar el nivel requerido de protección para el 2035. Además, las componentes episódicas de la inundación (riadas e inundación marina) pueden ser consideradas las más relevantes a lo largo de la costa con valores en general de riego medio. La componente de inundación a largo plazo (SNM) solo tiene efectos en costas bajas, siendo el delta del Ebro el más importante. Los resultados indican la comarca del Maresme como la región más sensible a las componentes provocadas por tormentas en la costa catalana.
La red viaria que da servicio a la movilidad debería responder a los retos de la sostenibilidad y a la nueva manera de entender el territorio desde una lectura sistémica, histórica y topológica. La respuesta es una red viaria de enfoque local que dé servicio a los recursos activos del territorio y cuya gestión se comprometa con los múltiples usuarios de la red. Ante esto, ¿qué herramientas existen para transformar la red viaria vigente en una que sea sostenible y de proximidad?. A través del análisis de la accesibilidad a los recursos patrimoniales en curso de tres entornos diferenciados, se han identificado una serie de estrategias de actuación en esta línea. Asimismo, ha hecho emerger los estratos que intervienen en el proceso dando especial valor a los actores y los operadores como activadores de su dinamismo. Junto con este análisis propositivo, se ha caracterizado la red viaria local según su potencial a la peatonalidad y a la conectividad de los recursos territoriales.Si se centra la mirada en el usuario peatón en un entorno no-urbano, las estrategias de gestión deben dirigirse hacia la adecuación del viario intermedio (minor road) para el uso seguro y continuo del peatón, la articulación de los recursos del territorio local y la compatibilización de la funcionalidad cotidiana endógena con la exógena y turística. En esta investigación se proponen la intermodalidad, la continuidad y la funcionalidad basada en la territorialidad como los parámetros puntales a tener en cuenta al acondicionar la red viaria para el uso del peatón y convertirla en una red sostenible, local y que articula el sub-sistema patrimonial-cultural.
The road network service for mobility should respond to the challenges of sustainability and the new way of understanding the territory from a systemic, historical and topological perspective. In order to accomplish this goal, the management must give service to the active resources of the territory from a local approach and it must be responsible for the multiple users of the network. In view of this, what tools exist to change the current road network into one which is local and sustainable?
A number of strategies of this line of proceeding have been identified through the analysis of the current accessibility of the heritage resources of three different areas. In addition, it has brought to the surface elements involved in the process and has given added value to actors and operators as promoters of its dynamism. Together with this analysis which contains proposals, the essential criteria applied for defining the road network has borne in mind its potential for walkability and connectivity to territorial resources.
Taking into account pedestrians in non-urban areas, management strategies must focus on improving minor roads so that they are safer and continuous. They should also link local territorial resources and make exogenuous and touristic needs compatible with everyday endogenous functionality. There are three parameters in this research based on territoriality which are considered essential in the management of road network: intermodality, continuity and functionality. These parameters are key for the development of a more pedestrian friendly road network which articulates the heritage and cultural subsystem of a local territory.
La red viaria que da servicio a la movilidad debe responder a los retos de la sostenibilidad y a la
nueva manera de entender el territorio desde una lectura sistémica, histórica y topológica. La
respuesta es una red viaria de enfoque local que de servicio a los recursos activos del territorio y
cuya gestión se comprometa con los múltiples usuarios de la red. Ante esto, ¿qué herramientas
existen para transformar la red viaria vigente hacia una red sostenible y de proximidad?
A través del análisis de la accesibilidad a los recursos patrimoniales de tres entornos
diferenciados se han identificado una serie de estrategias de actuación vigentes en esta línea.
Asimismo, el análisis ha hecho emerger los estratos intervinientes en el proceso de la
accesibilidad patrimonial dando especial valor a los actores y los operadores como activadores de
su dinamismo. Junto con el análisis propositivo se ha caracterizado la red viaria local según su
potencial a la peatonalidad y a la conectividad de los recursos territoriales.
Si se centra la mirada en el usuario peatón en un entorno no-urbano las estrategias de gestión
deben dirigirse hacia la adecuación del viario intermedio para el uso seguro y continuo del
peatón, la articulación de los recursos del territorio local y la compatibilización de la
funcionalidad cotidiana endógena con la exógena y turística. En esta investigación se proponen la
intermodalidad, la continuidad y la funcionalidad basada en la territorialidad como los
parámetros puntales a tener en cuenta al acondicionar la red viaria para el uso del peatón y
convertirla en una red que articule el sub-sistema patrimonial y cultural del territorio local