Caractérisation minéralogique et géotechnique des argiles marneuses gonflantes de la région de Médéa,Algérie

This paper presents the approach followed for the geological, mineralogical, and geotechnical characterization of swelling marly clays in the Médéa region. This investigation is conducted in order to estimate the swelling potential of this marly clay layer. The studied sites, located at about 80 km south of Algiers, Algeria, cover an area of approximatively 400 hectares. Five sites are considered. In the first step, the geological, tectonic, climatic, and hydrological contexts of the region are described. According to the geological map of Médéa, most of the formations encountered in the area are composed of Miocene layers represented by marly clays (Fig. 2). This region is characterized by its high and low temperature in summer and winter, respectively, and variable humidity (Fig. 3). In a second step, the results of geotechnical studies, X-ray diffraction tests, chemical analyses, and scanning electron microscope (SEM) observations are presented (Figs. 3, 4, 5, 6, 7, 8, 9). The soils contain quartz (20–26 %), calcium carbonates (11–55 %), kaolinite (8–13 %), illite (6–14 %) and Montmorillonite (18–26 %). The study of their microstructure by means of SEM indicates that these soils are formed by a compact marly clay matrix that is relatively homogeneous and oriented in the dip direction of bedding. A grain size analysis shows that the clay content varies between 17 and 70 %. The water content of all samples varies between 8 and 30 %. The values of the liquidity limit (LL) and plasticity index (PI) vary between 28–76 % and 16–36 % respectively, indicating a highly plastic soil; this is also confirmed by a specific surface varying between 99 and 179 m²/g. The dry density γ _d varies between 15 and 19 kN/m³. The swelling potential of the marly clay samples is evaluated firstly using various indirect methods. In literature, a number of empirical classifications are proposed by different authors (BRE 1980; Chen 1988; Komornik and David 1969; Seed et al. 1962; Snethen 1984; Vijayvergiya et Ghazzaly 1973 et Williams and Donaldson 1980). The swelling potential is related to certain physical properties of soils, such as consistency limits, clay content, methylene blue value, etc. In general, these methods indicate that all the tested soils have a high swelling potential, which confirms the results of mineralogical analysis. Secondly, direct measurements of swelling parameters are performed. Swelling tests are carried out using a standard slaved one-dimensional odometer using two methods: free swell and constant volume, according to standard ASTM D 4546-90 and AFNOR (1995). The swell pressure, the swell percentage and the swell index are given in Fig. 16. It is noted that the soils develop very significant swell pressures which vary between 25 and 900 kPa. This is in agreement with the results obtained by empirical methods. This investigation clearly shows that the marly clays of the Médéa region have a high swelling potential. Therefore, taking into account the phenomenon of soil swelling in structure design is essential.     

Néotectonique et grands mouvements de versant. Le cas de Séchilienne (Isère, France)

In a homogeneous fracture massif, the release of stress related to the last glacial melting induces the opening of fractures inherited from the tectonic history of the rock mass. In some cases subsidence, similar to sagging from uphill facing scarps, occurs. The mechanism can be briefly described as bending of huge rock blades towards the valley, known as cambering. Nowadays the movements are due to climatic phenomena (rains, snow melting, frost, thaw, huge thermal difference) or mechanical ones such as seismic vibrations, the influence of which is generally more difficult to identify. The Séchilienne slope movement is located on the right bank of the river Romanche, about 20 km upstream of Grenoble, in the district of Isère, south east France, and is representative of this kind of phenomenon. This unstable slope has been affected by recurrent rock falls which, according to old records, were already mentioned in the eighteenth century. The rock mass is made of micaschist and psamites of early Palaeozoic age, belong to the external Belledonne alpine range which is still moving up at a rate of a few millimeters per year. As the terrain has had a long and complex geological history, characterized by five tectonic periods, the hazard geometry and slope movement directions are mainly controlled by faults associated with this succession of structural events. Of particular importance is a regional fault called the “faille de la Romanche” which is some 20 km long and extends from Séchilienne westwards to the Vercors limestone ridge and eastwards through the Taillefer massif to reach the Liassic terrain of the Oisans massif near the village of Ornon. This fault is located at the foot of the unstable slope. There are several arguments in favour of a recent movement of the Romanche fault. The first is linked to some regional geomorphological features such as the lozenger shape of the Romanche valley in the Séchilienne area. This feature resembles a pull-apart basin, bordered on the north and south by the Romanche fault and filled with more than 200 m of Quaternary alluvial sediments. In addition, since 1960 eleven earthquakes have affected the villages of Vizille and Séchilienne. One of these, the Laffrey earthquake (11 January 1999), had a magnitude of 3.5 with an epicenter located only 4 km south of the Séchilienne site. The monitoring devices installed on the slope allow an accurate analysis of the widespread displacements which occur in the area. The analysis has led to the establishment of the influence of the local seismicity on the observed movements. Slope displacements measured since 1985 have shown important speed variations between winter and summer and a progressive long term acceleration. A detailed analysis of the daily measurements shows an increase in the displacements from 29 January to 11 February 1999 without any associated rainfall. Moreover, a systematic examination of the successive slope accelerations related to meteoric water supply has shown that, since the 1999 Laffrey earthquake, the acceleration occurred with only a short delay of less than 24 h after the beginning of heavy rainfall compared with the delay of several days which was common before the 1999 earthquake.     

Essais systématiques de validation de formulations de sable sénégalais pour l'élaboration d'un sable normalisé

Résumé. Au Sénégal, pays en voie de développement, le sable normalisé employé pour la détermination des classes de résistance des ciments est importé. Un inventaire des ressources locales en sable a été conduit pour rechercher un produit de substitution au sable de Leucate. La première phase de l'étude a permis sur la base d'essais d'orientation, de mettre au point un mélange ternaire composé de deux sables roulés et d'un sable de concassage qui remplit les critères requis pour un "sable normalisé CEN". Dans la deuxième phase de l'étude, des essais systématiques croisés ont été menés à Rennes et à Dakar, ils confirment les résultats des essais d'orientation et les valident d'un point de vue statistique. Electronic Publication     

Caractéristiques des masses et marnes du gypse et de leurs faciès d'altération dans la région parisienne méthodologie des études géotechniques

The author presents the principal results of a research project concerning a geological formation widely represented in the natural region of Parisis, North of Paris, which is dreaded by geotechnicians: masses and interstratified marls of ludian gypsum. The impossibility of making ground observations essential to a thorough study of the phenomena of weathering of the gypsum, and notably its substitution, led to the work being undertaken along the following lines:

-Modelling of the geological infractructure of the gypseous slopes.

-The quest for indicators of the lithology and distribution of the residual masses and interstratified marls of gypsum, and the valuable role of diagraphs of natural radioactivity.

-The incidence of the weathering of the gypsum on the mechanical (pressiometric) characteristics of the gypseous areas.

-A methodology of geotechnical surveys on gypseous sites.

A progressive approach is proposed, beginning with a feasibility study, followed by a detailed study of the evolutive nature of the site, essential to the establishment of a suitably adapted project, and concluding with a mechanical characterisation necessary for the structural design of foundations.     

Une méthodologie d'analyse et de cartographie de l'aléa "initiation de laves torrentielles" – application au torrent du Bragousse (France)

Debris flows may result in personal injury or loss of life as well as damage to constructions. The economic consequences of such events are important, and likely to become more so with increasing urbanisation. In this paper, "debris flow" is defined as a viscous flow of saturated materials at high velocities of up to 20?m/s in channels. These materials have a high concentration of solids such that their dynamics may be considered at the interface between mechanical and hydraulic flow. The occurrence of a debris flow results from a number of interrelated factors including topography, geology, geomorphology and hydrogeology. The triggering factor is most often water, frequently a violent rainstorm. In order to identify the initiation mechanisms, it is necessary to have a knowledge of the environmental situation in the particular catchment area. Clearly, this will involve an understanding of: (1) the catchment area and its geological conditions; (2) the climatic characteristics of the locality and the nature of the materials in the source area; (3) the pattern of such events in the past. In order to obtain such an understanding, a dual approach of field and laboratory work was considered appropriate. Twelve catchment areas in the northern and southern French Alps were studied to assess the significance of the three aspects mentioned above. The study of numerous debris flow deposits sampled in these catchment areas suggested two types of debris flows: those with a cohesive matrix and those with a granular matrix. In the field, they were categorised on the basis of a morphological consideration of the area as well as according to the texture and grain size of the material in the flow. In the laboratory, granulometric tests were used. In addition, the granulometric and geotechnical characteristics of the source areas were compared with those of the debris flow materials. The grain size distribution appears to be an important factor in determining the likelihood that the source area materials would be moved by violent storms and from a debris flow. From tests undertaken on the <20?mm fraction, superficial deposits with between 16 and 40% of the particles of <50?μm seemed to be most likely to result in debris flows. This paper discusses the fieldwork undertaken from the upper catchment area down to the channel of a debris flow. Each mechanism is described with an analysis of the geological and topographical contexts, the extent of the movement and the hydrological processes that lead to the initiation of a debris flow. On the basis of this, maps have been produced to show the potential for the initiation of a debris flow. Five criteria were chosen to define the debris-flow hazard: (1) slope angle; (2) nature of the geological formation and hydrogeological characteristics; (3) slope erodability and instability; (4) grain size; (5) available volumes of superficial deposits present in the source area. These five indices form the global index. The maps show the spatial distribution of the hazard and can be useful in determining the most appropriate remedial/protective works to be undertaken in zones of the greatest risk.     

Altération et rupture d'échantillons d'argilite lors de sollicitations thermomécaniques en conditions humides contrôlées

The objective of this work was to undertake creep tests on shale and describe the microtextural phenomena which initiate internal damage/rupture under thermomechanical loading and relative humidity conditions. The CGI test cell is a system developed at the Centre de Geologie de l'Ingénieur specifically to allow observation of the fabric of a thick slide (50×40×5?mm) at different magnifications during the test. The CGI test cell imposes both an axial and a planar strain on the sample. The first step is to prepare a thick slide from a core and to describe its "initial" state. The second stage is to undertake a creep test to rupture, while the third step is to study the fragments of the ruptured material using XRD (X-ray diffractometry), SEM (scanning electron microscopy) and EDS (energy dispersive spectrometry). The samples studied are from the shales of the Callovo-Oxfordian of the Paris Basin, to the south of Bar-le-Duc in the east of France. These rocks consist of clay minerals (illite and kaolinite), quartz, calcite (22.8%), dolomite, feldspar and pyrite (1%). The pyrite is essentially found in the bioclasts. The creep test is carried out under thermomechanical loading with an axial stress of up to 12?MPa and a temperature rising to 80??°C. The relative humidity is maintained at more than 90%. After 33?days the axial strain reached 0.76%, with rupture of the thick slide occurring 10?days later. The deformation was related to the texture/heterogeneity of the rock and occurred mainly along fissuring. Rupture also occurred along bedding planes, particularly where oxidized pyritic bioclasts were present. The chemical phenomena noted were in part related to the formation of iron hydroxides and sulphuric acid. This reacts with the calcite to form gypsum, which has a lower density than the original pyrite and calcite. The XRD indicated that the iron hydroxides observed on the discontinuities are dominantly limmonite. Examination of the SEM and EDS suggested an increase in porosity, even at some distance from the macroscopic fissures.     

Valorisation de nouveaux matériaux naturels et recyclés dans la construction routière en Algérie

These recent years, the development of the civil engineering and especially the public works sectors in Algeria requires large amount of aggregates. Therefore, the abusive uncontrolled extraction of materials send out distress signals on the over-exploitation and reduction of the usual natural sources of aggregates, particularly alluvial deposits. Indeed, this can certainly maximize the risks of environmental contamination and threaten the aggregates supply continuity of projects, therefore seriously disturbing the development of the public work sector. For those reasons, the exploitation of new aggregates sources and the search for new local materials (natural or recycled materials) are urgently needed and seem to be a promising solution for sustainable development. Indeed, many natural materials such as (schist, marl,…) have been investigated in this area, given their availability and ease of extraction. Also, tons of inert wastes (concrete debris, glass debris,…) are generated from various human activities and abandoned in nature (along the roads) or buried in landfills where they surely represent contamination threats to ground water, while, these materials can be recovered and reused as alternative aggregates in important industrial sectors such as civil engineering and public works. The present experimental study is conducted in this context. It aims at valorizing local natural materials (marl) and recycled materials (glass debris) in road construction. Indeed, marl is among the most available materials in Algeria, it represents over 40% of the soils of Great Kabylia (Tizi-Ouzou). It is close to the surface (accessibility), with thicknesses exceeding 1000 meters (availability). Glass debris are also among the most available types of wastes (found in dumps and landfills). It is widely used in many industrial activities such as packaging, decoration, construction, and therefore it generates a lot of inert waste which take about 5000 years to decompose. For those reasons (large amounts and lengthy decomposition), several studies have been carried out for the glass possible reuse in civil engineering, especially in concrete and roads. To achieve this work, samples are prepared in the form of mixtures of marl with different proportions of glass debris (0, 10, 20, 30 and 40%). They are then submitted after identification to the main mechanical road tests, namely: compaction with modified Proctor tests in order to assess their maximal dry density, penetration with CBR tests (California Bearing Ratio) to evaluate puncture strength immediately under the circulation of vehicles during the construction of pavements or after soaking under water for 4 days (96 h), representing the worst humidity conditions on construction site. The samples are then subjected to direct shear tests using Casagrande shear box to assess their shear strength under traffic, especially during acceleration and braking of heavy vehicles. Finally, they are subjected to fragmentability, degradability, Los Angeles and micro-Deval tests to evaluate the evolution of the grains under different mechanical efforts (traffic, climatic and hydro-geological conditions). The experiments carried out have shown very remarkable results. Unlike the unfavorable behavior showed by the marl or the glass alone; their combination as mixtures presents very interesting mechanical characteristics under the different tests. Particularly, the mixtures with 20% of glass debris have shown the best aptitude to compaction, at low water content, and a high penetration strength in soaked and un-soaked conditions. In addition, it exhibits very interesting mechanical characteristics at shearing, with acceptable fragmentability, degradability, impact and wear behaviors. These results are very valuable and fully satisfy the requirements of standards for materials used in roads under weak and medium traffic. However, to better understand and develop the use of the studied materials in the road construction; further tests are necessary, such as long-term tests under cyclic natural loading (temperature, freeze–thaw,…). This research work may have considerable interests, both on the economical aspect and on the environmental impact in the region, mainly:

• Conservation of alluvial deposits and exploitation of new sources of aggregates to ensure the projects supply.
• Preservation of the environment by recovering abandoned glass wastes in nature, consequently, allowing the recovering of important storage spaces and significantly reducing the needs for new landfills.
• Contribution to the development of the recycling industries and the creation of more employment opportunities for the local population, leading to income generation and poverty reduction in developing countries such as Algeria, which offers a fertile field of recyclable materials (concrete, plastic, glass,…).

However, this study must be accompanied by appropriate and selective dumps installation strategies, with a large sensitizing of population in order to allow the easy collection of glass debris and other materials that can be recycled in the civil engineering field and other construction fields.

     

Apport d’une base de données d’éboulements rocheux obtenue par scanner laser dans la caractérisation des conditions de rupture et processus associés

Using laser scanner data, an exhaustive rockfall database has been established for a rockwall located near the town of Grenoble (France). The study site is a long double cliff, on the eastern border of the Chartreuse Massif. The two cliffs consist respectively of thinly bedded and massive limestone, which show different structures, morphologies and rockfall activities. The 3D point clouds obtained by laser scanner allow to detect and model the fallen compartments in 3D. Information about cliff surface, and localization, dimensions, failure mechanism for each compartment were obtained and analyzed in order to characterize the morphological evolutions of the cliffs. It appears that the morphology and the slope of the lower cliff is related to fracturing and torrential erosion which occurs in the marls below the cliff, showing a rockfall frequency 22 times higher than for the upper cliff. These results show that the erosion process in the lower cliff is in a transient state, whereas it could be in a steady state in the upper cliff. Rockfalls have been dated by a near-continuous photographic survey (1 photo each 10 mn) and a monthly survey during 2.5 years. The analysis of the two data bases shows that the rockfall frequency is 7 times higher during freeze-thaw episodes than without meteorological event, and 4.5 times higher during rainfall episodes. Moreover, it becomes 26 times higher when the mean rainfall intensity is higher than 5 mm/h. Based on these results, a 3-level hazard scale has been proposed for hazard prediction.

     

Exploitation de bambous (Sinarundinaria alpina (K. Schum.) C.S. Chao & Renvoize), cause des conflits entre le Parc National de Kahuzi-Biega et la population environnante: stratégie de conservation et de résolution de conflit

Sinarundinaria alpina is a species of mountain bamboo which is a source of various conflicts between the managers of the Kahuzi-Biega National Park (KBNP) and surrounding communities. This mountainous species is threatened by these communities to meet their need for various uses. Six permanent plots of 3 hectares were set between 2000–3000 metres above sea level and floristic inventories were made. In addition, information related to anthropogenic threats related to bamboo exploitation was recorded. All data were analysed using quantitative statistical parameters. Results suggest the existence of 196 species in these six permanent plots of the group Bamboo. The position of this Sinarundinaria alpina vegetation in the dynamic rainforest recovery dynamics is confirmed by the presence of trees and tree-nurseries of these trees. Fifty-three species, 27% of the plants observed, including Sinarundinaria alpina seedlings, contribute to the daily feeding of great apes, mainly Grauer’s Gorilla (Gorilla beringei graueri). This forest appears to be one of their critical habitats. The decrease in the area covered by bamboos is due primarily to anthropogenic activities but also some natural hazards (expansion of Sericostachys scandens, natural fading of Bamboo and attacks by beetles). Following these findings, conservation strategies were proposed. Several strengths were noted, including multiplication of bamboo nurseries and distribution of seedlings to local communities. This can be seen as a strong development of this sector in the future. This study is a preliminary assessment for further investigation.     

Impacts de recouvrements de résidus organiques sur des résidus miniers réactifs

Résumé Les résidus miniers constituent aujourd'hui un problème environmental important. En particulier, les résidus miniers à l'origine du drainage minier acide (DMA) sont les résidus provenant de l'exploitation de minerais tels que l'or, le cuivre, le zinc, le plomb, le nickel, ainsi que le charbon, qui contiennent des minéraux sulfurés généralement associés en formation primaire. L'action intensive et prolongée de l'oxygène atmosphérique et de l'eau de pluie sur les minéraux sulfurés résiduaires contenus dans la zone non saturée des haldes minières conduit à une production d'acide sulfurique. L'une des solutions envisagée pour empêcher la formation de la DMA consiste en un recouvrement des résidus miniers par une couche de matériaux afin de les isoler de l'oxygène atmosphérique. Parmi les matériaux pouvant être utilisés, on trouve ceux composés par des résidus organiques qui peuvent eux-mêmes être composés de différents types. Plusieurs études ont déjà mis en évidence l'efficacité de ces matériaux organiques comme barrière à l'oxygène. Un aspect important qu'il reste à étudier a trait aux interactions entre la couche organique (et ses produits de dégradation) avec les résidus oxydés et non oxydés. Le but de cet article est de présenter les mécanismes théoriques de formation de la DMA et l'utilisation de couches de résidus organiques comme moyen d'y remédier. L'interaction entre les couches de résidus miniers et les couches de résidus organiques est aussi discutée compte tenu de l'importance de ce sujet dans les domaines miniers, civils et environnementaux.

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Différentes déclinaisons de l'aléa liquéfaction: de la cartographie préventive au projet

As part of its Public Service, Applied Research, and Client Service activities, BRGM's Thematic Centre for Natural Geological Risks (NGR) has recently undertaken studies in order to characterize "liquefaction hazard". The paper considers definitions and presents several approaches to liquefaction hazard assessment, demonstrated by several examples. The first approach is a naturalistic one: Hazard assessment is considered in a structured manner by undertaking: – a regional inventory of historic events – mapping of formations susceptible to liquefaction in homogeneous risk areas subject to seimic activity – preventive mapping of the phenomena at local scale The second approach is a semi-deterministic one: It allows to produce a seismic microzonation, considering parametric calculations and charts (Seed's reverse method). This approach can be used also to recommend soil improvements when liquefaction hazard does exist. The third approach is a deterministic approach: It takes into account a 3D geotechnical model of the analysed area, as well as specific charts to produce a liquefaction hazard assessment of soils and an advanced seismic microzonation. This method was used in Guadeloupe and Martinique districts (French Lesser Antilles) ad for the design of a new TGV railway track in the south of France. The proposed methodology relies on the French Association for Earthquake Engineering recommendations and brings some innovative aspects: combined naturalistic and geotechnical analyses for liquefaction hazard assessment, combined chart use and 3D geotechnical modelling for liquefaction hazard microzonation. Apart from the complete analysis of the liquefaction hazard not always being useful, it also demands major resources, and is consequently sometimes broken down into several less-detailed stages. The various examples considered thus form a continuum and are simply variations of a same definition of the liquefaction hazard: where: X, Y and Z=coordinates t=time Δu=interstitial over-pressure σ'_vo=initial effective stress I_L=Iwasaki's liquefaction index     

Évaluation et cartographie des risques géotechniques de dégradation des ouvrages d'assainissement une aide à la gestion des eéseaux

A sewage collector can be considered as a composite structure, comprising the collector itself and its geological envelope both sticking together. Its durability is directly linked with the geotechnical behaviour of the soil, as testified by the analysis of numerous pathological cases observed in structures which it is possible to inspect in the Paris urban area. The author proposes a methodology enabling these parameters of influence to be taken into account without recourses to costly procedures of investigation. Based on the principles of mapping risks of soil movements, the method involves two stages:

-The geotechnical classification of soils in terms of their vulnerability to stresses to which they may be subjected.

-The establishments of maps or profiles predictive of risks. in accordance with qualitative criteria derived from the interpretation of existing geological information.

Tested and applied to the inspectable sewage system of the Val-de-Marne and Seine-Saint-Denis Departments, this procedure can be extended to urban systems where sufficient geotechnical documentation is available to obviate the need for any in situ investigation.     

Contribution à l’étude du mouvement de terrain de la ville de Tigzirt (Algérie)

This article is a contribution to the study of the causes, characterization, and numerical modeling, using finite elements, of the landslide affecting the coastal slope at the edge of the Mediterranean Sea near the city center of Tigzirt (Algeria). This slope is characterized by a relatively low inclination (13°–15°) and composed of two main geological formations (marly bedrock overlain by recent Quaternary deposits). Several factors have acted jointly and explain the activity of Tigzirt landslide: it is the effect of geological, morphological, and hydrogeological site contexts combined to triggering factors of various origins (human, climatic, and seismic). The landslide is characterized by a planar failure surface, which involves a global translational deformation towards the sea.     

Le béton de cosse de riz pour panneaux legers

A project by the Eduardo Torroja Institute in Madrid has focused on the mechanical performance of lightweight panels (= 30 kg) based on concrete made with rice husks treated with lime. The 6 cm thick components measure 90 × 60 cm and are hand‐formed to accord with methods that are suitable for developing countries. The article discusses the results of tests for flexure and axial compression on short series of these components.     

Le Pont Vasco de Gama – la démarche durabilité

From the concrete example of a large construction, this paper aims to show how the results obtained from the research work carried out on transfer in cement pastes were applied both on site during the concrete construction and in the laboratory to predict the durability of the concrete structure. This unique process, carried out in close collaboration with the constructor, is based on a new concept of High Performance Concrete. The construction concerned is the Vasco da Gama Bridge in Lisbon, which is one of the most important bridges ever constructed in Europe: it is more than 17?km long, built in the maritime zone on the Tagus river estuary. It was opened in April 1998. A guarantee of life duration of 120?years, without major maintenance, has been demanded. In addition to the criteria relative to the concrete constituents (non-reactive aggregates with regard to the alkalireaction, the nature of the cement and a formulation adapted to the direct environmental effects on the different construction parts), one of the main life duration criteria selected is a chloride concentration limit value of 0.4%, compared to the mass of the cement, measured directly at the reinforcement steel position. This value determines the initiation threshold of the corrosion process of steel. Specifications are both a diffusivity coefficient of chloride of less than 1×10^–12?m²?s^–1 determined by the TANG Luping method and an oxygen permeability of less than 1×10^–17?m². These basic criteria have been perfected by measures of porosity to water, tests of resistance to chloride penetration, chloride migration tests and also by extensive examinations of the concrete microstructure. All the measurements and tests have been undertaken both on concrete samples made in the laboratory and on samples made on site and concrete cores from parts of the structure built in 1995. Coefficients of chloride diffusivity measured or calculated from profiles of concentration in concrete cores have been used in a predictive model, using a finite element method integrating the interaction ions with cement paste and the evolution of the diffusivity coefficient in time. The various computing simulations, improved progressively with controls and after comparison with the real bridge, tend to confirm, on the one hand, the validity of the model used and, on the other hand, the accuracy of the chosen formulations. These formulations, having mechanical properties close to those of High Performance Concrete, also have special microstructural properties of diffusivity and permeability, answering the requirements of the durability of this bridge.