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    <title>Transport Research International Documentation (TRID)</title>
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    <language>en-us</language>
    <copyright>Copyright © 2026. National Academy of Sciences. All rights reserved.</copyright>
    <docs>http://blogs.law.harvard.edu/tech/rss</docs>
    <managingEditor>tris-trb@nas.edu (Bill McLeod)</managingEditor>
    <webMaster>tris-trb@nas.edu (Bill McLeod)</webMaster>
    <image>
      <title>Transport Research International Documentation (TRID)</title>
      <url>https://trid.trb.org/Images/PageHeader-wTitle.jpg</url>
      <link>https://trid.trb.org/</link>
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    <item>
      <title>TBM and spoil treatment selection process - case history Crossrail C310 Thames Tunnel. Slurry TBM versus EPB TBM</title>
      <link>https://trid.trb.org/View/1310676</link>
      <description><![CDATA[The contract C310 comprises the construction of the Plumstead and North Woolwich Portals and the twin tube Thames Tunnel, which has a length of approximately 2.6 km between the two portals. The two TBMs used for the construction of the Thames Tunnel will drive through varying ground conditions (Thanet Sand, River Terrace Deposit (gravel), and chalk) below the water table. During the drive under the River Thames, the tunnels will only have an overburden of approximately 12 m. The effect of pressure variation due to the tidal River Thames has to be accounted for in the control of the tunnelling. The tunnel will pass underneath several grade II listed buildings, utilities, adjacent to operational railway tracks and close to existing subway tunnels. Previous experience of the handling and disposal of excavated chalk has been gained on several tunnelling projects in chalk, most notably the Dartford Road Tunnels, the Channel Tunnel, the Brighton Stormwater Tunnel, the Lille Metro Tunnel, the Socatop Road Tunnel near Paris and Channel Tunnel Rail Link CTRL 320. The contract allowed for both mixshield and EPB TBM technology. The advantages and disadvantages of a TBM-S with earth pressure balanced face support (EPB-TBM) and a TBM-S with slurry face support (Mix-Shield TBM) for the C310 Thames Tunnels were discussed after contract award and a comparative risk assessment was developed. A mixshield TBM is more expensive but outperformed the EPB TBM in the overall scoring of risk assessment and therefore it has been decided to use this type at C310. (A)]]></description>
      <pubDate>Tue, 27 May 2014 16:56:11 GMT</pubDate>
      <guid>https://trid.trb.org/View/1310676</guid>
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    <item>
      <title>An early warning system for groundwater flooding in the Chalk</title>
      <link>https://trid.trb.org/View/1084475</link>
      <description><![CDATA[An early warning system has been developed for groundwater flooding and trialled in the Patcham area of Brighton. It provides a fit-for-purpose approach for forecasting groundwater flood events in the Chalk and is capable of operating across longer time scales than had previously been possible. The method involves a set of nested steps or tasks. Initially, the catchment's response to recharge is determined and, using a representative hydrograph, a simple regression model that relates annual groundwater level minima and autumn and winter rainfall to subsequent annual maxima is developed. The regression model is then applied at the end of each summer recession using the observed annual minimum and estimates of winter rainfall to predict the following groundwater level maximum. Based on the results of this prediction a variety of steps may then be appropriate. Where the model predicts potentially high groundwater levels the frequency of groundwater level monitoring observations can be increased. A novel element of the method developed is the monitoring of changes in the matric potential of the unsaturated zone. Specific trigger levels to initiate either the next step of the method or promulgation of warnings of varying severity will be developed through experience of use of the system.]]></description>
      <pubDate>Wed, 22 Dec 2010 08:36:03 GMT</pubDate>
      <guid>https://trid.trb.org/View/1084475</guid>
    </item>
    <item>
      <title>THE STABILIZATION OF QUARRIES UNDER THE H6 MOTORWAY</title>
      <link>https://trid.trb.org/View/1081144</link>
      <description><![CDATA[AFTER GIVING SOME BRIEF DETAILS ON OLD QUARRIES IN PARIS AND ITS SUBURBS (FRESH WATER LIMESTONE, GYPSUM, AND CHALK QUARRIES), THE AUTHORS DESCRIBE THE AIM AND ORGANISATION OF THE "INSPECTION GENERALE DES CARRIERES" (GENERAL INSPECTION OF QUARRIES), AN INTERDEPARTMENTAL SECTION UNDER THE ADMINISTRATION OF THE PARIS PREFECTURE WHICH COLLECTS CARTOGRAPHIC DATA ON QUARRIES IN PARIS, THE HAUTS DE SEINE, SEINE SAINT-DENIS AND VAL DE MARNE. THIS ORGANIZATION DEALS WITH DEMANDS FOR CONSTRUCTION PERMITS, GIVES INFORMATION ON THE NATURE OF THE SOIL AND SUBSOIL, CHECKS AND STABILISES OLD QUARRIES. THE STABILIZATION PROCEDURES USED FOR THE H6 MOTORWAY ARE CITED AS EXAMPLES.]]></description>
      <pubDate>Sun, 21 Nov 2010 18:28:28 GMT</pubDate>
      <guid>https://trid.trb.org/View/1081144</guid>
    </item>
    <item>
      <title>THE RECONSTRUCTION OF THE ALMA BRIDGE</title>
      <link>https://trid.trb.org/View/1078072</link>
      <description><![CDATA[THE NEW ALMA BRIDGE IS 42 M WIDE; IT SUPPORTS 2 14 M-WIDE CARRIAGEWAYS, SEPARATED BY A 2M-WIDE CENTRAL RESERVE AND HAS 2 LATERAL FOOTPATHS 6 M WIDE  EACH. IT IS APPROXIMATELY 150 M LONG, INCLUDING THE ABUTMENTS. AFTER THE  OPENING OF THE NEW UPSTREAM HALF-BRIDGE TO TRAFFIC, THE PRESENT BRIDGE WILL BE DEMOLISHED AND THE CONSTRUCTION OF THE DOWNSTREAM HALF-BRIDGE WILL BE STARTED AT THE SITE OF THE PRESENT BRIDGE. THE LONGITUDINAL PROFILE OF THE NEW BRIDGE CONSISTS OF A CIRCULAR ARC WITH A RADIUS OF 1407 M CONNECTED AT ITS EXTREMITIES TO ACCESS RAMPS. BECAUSE OF THE VERY LOW QUALITY OF THE FOUNDATION LAYERS, THE FOUNDATION OF THE NEW STRUCTURE HAD TO BE ON CHALK. DUE TO NAVIGATION REQUIREMENTS AND TO THE HIGH COST OF THE RIVER BEARINGS (THE BEARINGS HAVING TO GO TO A GREAT DEPTH) THE NEW BRIDGE HAS ONLY ONE RIVER BEARING. THE DECK COMPRISES TWO SPANS (110M AND 31,50M )CONSISTING OF BOX GIRDERS UNDER A HIGH-STRENGTH STEEL CARRIAGEWAY SUPPORTING A REINFORCED CONCRETE SLAB OF THE ROBINSON TYPE. THE ABUTMENTS ARE FOUNDED ON DRILLED REINFORCED CONCRETE PILES, 1,08 M IN DIAMETER ANCHORED IN CHALK. THE  MAXIMUM STRESSES AT THE FOOT OF THE PILES ARE 30 BARS UNDER CONTINUED LOAD AND 40 BARS WITH OVERLOAD. THE PIER IS FOUNDED ON SLURRY TRENCH WALLS 6,26M WIDE AND 0.80M THICK ANCHORED IN CHALK. BRIEF DETAILS ARE GIVEN OF THE SERVICE MAINS INSIDE THE BOX GIRDER, STAGES OF ERECTION, CORNICE AND PARAPETS, AND PROTECTION OF THE BOX GIRDERS AGAINST CORROSION. THE MAIN QUANTITIES OF MATERIALS USED ARE QUOTED. THIS ARTICLE IS IN FRENCH.]]></description>
      <pubDate>Sun, 21 Nov 2010 16:41:50 GMT</pubDate>
      <guid>https://trid.trb.org/View/1078072</guid>
    </item>
    <item>
      <title>RECONSTRUCTION OF THE BRIDGE OVER THE SEINE AT CONFLANS (FRANCE)</title>
      <link>https://trid.trb.org/View/1078051</link>
      <description><![CDATA[THE OLD BRIDGE IN CONFLANS 174M LONG, CONSISTED OF THREE METAL ARCHES. DURING THE CONSTRUCTION OF THE A4 PARIS- STRASBOURG MOTORWAY IT WAS REPLACED  BY TWO PARALLEL STRUCTURES POSITIONED RESPECTIVELY AT THE SITE OF THE OLD BRIDGE AND DOWNSTREAM OF THE EXISTING STRUCTURE; THE NEW STRUCTURES CARRY A ONE-WAY CARRIAGEWAY EACH. THE DOWNSTREAM BRIDGE CONSISTS OF A CONTINUOUS PRESTRESSED CONCRETE DECK WITH 3 SPANS(45,55M, 66M AND 45,55M). THE DECK IS ELASTICALLY RESTRAINED ON PIERS AND SIMPLY RESTING ON ABUTMENTS. IT WILL CARRY THREE TRAFFIC LANES AND A FOOTPATH. THE DECK CONSISTS OF TWO BOX  GIRDERS OF CONSTANT HEIGHT. THE STRUCTURE IS CANTILEVERED OVER PIERS AND  ABUTMENTS, THE PRECAST CONCRETE SEGMENTS HAVING GLUED JOINTS. THE DECK IS IS TRANSVERSALLY AND LONGITUDINALLY PRESTRESSED. IN THE DECK THERE ARE DUCTS FOR WATER AND GAS MAINS, TELEPHONE CABLES, ETC. THE PIERS IN THE RIVER ARE FOUNDED ON TWO COLUMNS RESTRAINED IN CHALK. THE ABUTMENTS ARE FOUNDED ON LARGE- DIAMETER DRILLED PILES. ACCESS VIADUCTS HAVE A PAVEMENT SLAB OF 3,20M EXTENDED BY MEANS OF CANTILEVERED BEAMS AND LONGITUDINALLY STIFFENED BY MEANS OF RIBS. THIS ARTICLE IS IN FRENCH.]]></description>
      <pubDate>Sun, 21 Nov 2010 16:41:04 GMT</pubDate>
      <guid>https://trid.trb.org/View/1078051</guid>
    </item>
    <item>
      <title>CONSTRUCTION OF THE OISSEL BRIDGE CARRYING THE A13 PARIS- NORMANDIE MOTORWAY</title>
      <link>https://trid.trb.org/View/1078010</link>
      <description><![CDATA[THE A13 PARIS-NORMANDIE MOTORWAY CROSSES THE SEINE IMMEDIATELY UPSTREAM OF ROUEN BY MEANS OF THE OISSEL BRIDGE. IT IS A CONTINUOUS PRESTRESSED CONCRETE NINE-SPAN STRUCTURE. A 10-M HIGH EMBANKMENT HAD TO BE BUILT ON THE RIGHT BANK OF THE RIVER, THE LEFT BANK BEING HIGHER. THE DIFFERENCE IN LEVEL  BETWEEN THE TWO EXTREMITIES OF THE BRIDGE IS 14M. THE TOTAL LENGTH OF 750M IS DISTRIBUTED OVER FIVE 1000M LONG CENTRAL SPANS, TWO INTERMEDIARY 75M  LONG SPANS AND TWO 50M SPANS ON THE RIVER BANKS, WHICH LIMIT THE SIZE OF  THE ABUTMENTS. THE BRIDGE HAS TWO DECKS PLACED SIDE BY SIDE, EACH CARRYING ONE CARRIAGEWAY WITH 4 LANES IN EACH DIRECTION . THE SUBGRADE CONSISTS OF COMPACT GREY CHALK UNDERLYING A HARD CHALK FLINT. ON THE RIGHT BANK THERE IS A THICK LAYER OF ALLUVIUM, ON THE LEFT BANK APPROXIMATELY 5M-THICK CHALK DEBRIS. CYLINDRICAL PIERS HAVE MASSIVE METAL CAISSON ON REINFORCED CONCRETE FOUNDATIONS. THE END PIERS ARE FOUNDED ON WELLS PLACED IN THE SHAPE  OF A CROWN. THE ABUTMENTS COMPRISING TWO INDEPENDENT HALF-ABUTMENTS ARE SUPPORTED BY 1,50M THICK FOOTINGS. DETAILS ARE GIVEN OF THE BEARINGS, EXPANSION JOINTS, THREE-WEB CAISSONS FORMING THE DECKS, CROSS BARS, PIERS, PRESTRESSING OF THE UPPER SLAB, ETC. CONCRETE IS TRANSPORTED BY CABLE-CRANE FROM TWO MIXING PLANTS (20 AND 30 M3/H). THE SEGMENTS ON PIERS ARE BUILT WITH THE HELP OF CONVENTIONAL SCAFFOLDING. THE EARLY STARTING DATE OF THE STUDY ENABLED A SERIES OF BORE HOLES TO BE COMPLETED BEFORE TENDERING AND THE SETTLEMENT OF THE EMBANKMENTS TO BE ACHIEVED BEFORE WORK STARTED.]]></description>
      <pubDate>Sun, 21 Nov 2010 16:39:41 GMT</pubDate>
      <guid>https://trid.trb.org/View/1078010</guid>
    </item>
    <item>
      <title>STABILIZATION OF CHALKY SOIL WITH GRANULATED SLAG</title>
      <link>https://trid.trb.org/View/1074970</link>
      <description><![CDATA[THIS ARTICLE DESCRIBES AN INVESTIGATION INTO TTHE POSSIBILITY OF USING CHALKY MATERIALS (SAND AND GRAVEL) , PARTICULARLY ABUNDANT IN PICARDIE AND CHAMPAGNE, IN ROAD CONSTRUCTION. IN THE PAST, THE UTILIZATION OF NON-STABILISED CHALKY MATERIALS RESULTED IN WEAR AND SENSITIVITY TO FROST; THUS THE STABILIZATION OF CHALKY SAND WITH GRANULATED SLAG , ASSUMING ADEQUATE COATING OF CHALK PARTICLES WITH THE SLAG, WAS SUCESSFULLY USED. VARIOUS FACTORS WERE STUDIED, SUCH AS PROPORTIONING AND REACTIVITY OF THE SLAG, COMPACTION RATIO OF SAMPLES, TIME-RELATED EVOLUTION OF MECHANICAL STRENGTH. RESULTS SHOW THAT ADEQUATE FINAL STRENGTH AND RATE OF SETTING CAN BE ACHIEVED IF  THE REACTIVITY AND THE PROPORTIONING ARE CAREFULLY CALCULATED, THE FINAL  STRENGTH AND RATE OF SETTING BEING THE TWO MOST IMPORTANT CHARACTERISTICS AS REGARDS FROST BEHAVIOUR. THE CONCLUSIONS REACHED IN THE STUDY WILL HAVE TO BE ADAPTED AS A FUNCTION OF THE DIFFERENT NATURE OF VARIOUS DEPOSITS. CHALKY MATERIALS STABILIZED WITH GRANULATED SLAG SHOULD ONLY BE USED IN THE CONSTRUCTION OF ROAD BASES OF LIGHTLY-TRAFFICKED ROADS (CHALKY SAND) OR HEAVILY-TRAFFICKED (CHALKY GRAVEL) .]]></description>
      <pubDate>Sun, 21 Nov 2010 14:50:01 GMT</pubDate>
      <guid>https://trid.trb.org/View/1074970</guid>
    </item>
    <item>
      <title>THE NEW SAINT-CLOUD BRIDGE OVER THE EXTENSION OF THE A13 SAINT-CLOUD MOTORWAY IN PARIS</title>
      <link>https://trid.trb.org/View/1074943</link>
      <description><![CDATA[THE STRUCTURE CONSISTS OF A 574-M ACCESS VIADUCT AND A 529M-BRIDGE OVER THE SEINE. THE FOUNDATION OF THE ACCESS VIADUCT GOES THROUGH SCREE MATERIAL  THANKS TO A DEVICE, WHICH COMPRISES A COMPRESSIBLE METAL PART THAT REDUCES THE ACTIVE EARTH PRESSURE ON THE PIERS. THE PART ABOVE THE SEINE RESTS ON TWO PIERS WHICH ARE ALIGNED ON THE CURRENT BUT ARE MARKEDLY SKEWED TO THE AXIS OF THE STRUCTURE; THESE PIERS WERE BUILT INSIDE ENCLOSING SHEETING. BECAUSE OF THE WEATHERED CONDITIONS OF THE CHALK, ON WHICH THEY ARE RESTING, THE LONG PILES USED WERE FIXED IN THE SUBGRADE. THE DECK IS A MULTICELL BOX-GIRDER CONSISTING OF PRECAST SEGMENTS, INSTALLED WITH A TRANSPORTER  AND ASSEMBLED BY MEANS OF PRESTRESSING. NUMEROUS DRAWINGS AND PHOTOGRAPHS ARE APPENDED.]]></description>
      <pubDate>Sun, 21 Nov 2010 14:49:21 GMT</pubDate>
      <guid>https://trid.trb.org/View/1074943</guid>
    </item>
    <item>
      <title>GENERAL CONCLUSIONS AND RECOMMENDATIONS</title>
      <link>https://trid.trb.org/View/1074915</link>
      <description><![CDATA[THE SYMPOSIUM ON CHALK GAVE THE OPPORTUNITY OF STUDYING A NUMBER OF PROBLEMS ENCOUNTERED IN CIVIL ENGINEERING: EARTHWORKS, FOUNDATIONS UNDERGROUND CONSTRUCTION WORKS. MENTION IS MADE OF THE SOLUTIONS OFFERED BY GEOLOGY, PETROPHYSICS AND GEOTECHNICS AND THEORETICAL AND PRACTICAL INVESTIGATIONS. THE CONCLUSIONS REACHED AT THE SYMPOSIUM CONCERN RESEARCH METHODOLOGY, NEW  TECHNIQUES, CHANGES IN THE CHALK UNDER STATIC AND DYNAMIC LOADING, AND RESEARCH TO BE UNDERTAKEN. RECOMMENDATIONS ARE PUT FORWARD IN THE USE OF CHALK IN LOW EMBANKMENTS (LOWER THAN 5M) AND HIGH ONES (OVER 12M). A CLASSIFICATION IS PROPOSED ACCORDING TO THE HARDNESS OF THE MATERIAL: HARD, MEDIUM AND SOFT CHALK.]]></description>
      <pubDate>Sun, 21 Nov 2010 14:48:29 GMT</pubDate>
      <guid>https://trid.trb.org/View/1074915</guid>
    </item>
    <item>
      <title>UNDERGROUND CAVITIES IN CHALK IN NORTHERN FRANCE</title>
      <link>https://trid.trb.org/View/1074914</link>
      <description><![CDATA[THE FIRST STEP IN THE STUDY IS A THOROUGH KNOWLEDGE OF THE GEOLOGY OF THE  REGION. THE SECOND STAGE IS THE CONDUCT OF GRAVIMETRIC INVESTIGATIONS. THE ELECTROMAGNETIC METHOD WAS DEVELOPED BY PROFESSOR GABILLARD TO CARRY OUT INVESTIGATIONS INTO CAVITIES OF THE SO CALLED "BOTTLE" TYPE IN THE REGION AROUND LILLE. WHEN GRAVIMETRIC OR ELECTROMAGNETIC INVESTIGATIONS HAVE SHOWN ANOMALIES CAUSED BY UNDERGROUND CAVITIES, IT IS NECESSARY TO APPLY MECHANICAL INVESTIGATION METHODS. IN THE EASY CASES OF NUMEROUS ACCESS SHAFTS, SHALLOW CAVITIES, PENETROMETERS CAN BE USED; IF THIS IS IMPOSSIBLE, BORING TECHNIQUES MUST BE UTILIZED. THE LAST STEP TO BE TAKEN, ONCE A CAVITY HAS BEEN IDENTIFIED, IS TO GO INTO IT FOR INSPECTION. THE FOLLOWING METHODS  CAN BE USED TO DEAL WITH CAVITIES IN CHALK: BLOCKING UP OR TREATMENT OF THE CAVITY ACCORDING TO CONDITIONS ENCOUNTERED. BLOCKING UP, WHICH IS AN UNFAILING BUT EXPENSIVE SOLUTION IS CARRIED OUT EITHER BY MEANS OF QUARRY AGGREGATE LAID PNEUMATICALLY OR BY INJECTION OF FLY ASH/CEMENT GROUT, THE LATTER SOLUTION BEING MORE RELIABLE AND LESS EXPENSIVE. THE SECOND METHOD OF TREATMENT MUST BE ADAPTED TO THE CONDITIONS ENCOUNTERED AND CAN THEREFORE TAKE VARIOUS FORMS, THE MOST SIMPLE BEING THE EXCAVATION OF ACCESS SHAFTS FOR PERIODICAL INSPECTIONS.]]></description>
      <pubDate>Sun, 21 Nov 2010 14:48:27 GMT</pubDate>
      <guid>https://trid.trb.org/View/1074914</guid>
    </item>
    <item>
      <title>EARTHWORKS PROBLEMS IN CHALK</title>
      <link>https://trid.trb.org/View/1074913</link>
      <description><![CDATA[THIS ARTICLE GIVES THE RESULTS OF INVESTIGATIONS INTO EARTHWORKS PROBLEMS  ENCOUNTERED IN CHALK. STANDARD GEOTECHNICAL TESTS (PARTICLE SIZE DISTRIBUTION, ATTERBERG LIMITS, MOISTURE CONTENT PROCTOR TEST) ARE NOT SUITABLE FOR IDENTIFYING CHALK, WHICH IS A MATERIAL IN EVOLUTION, THEREFORE WITH A BEHAVIOUR DIFFICULT TO FORECAST. THE INFLUENCE OF THE PERCENTAGE OF PASTE OR FINES IS UPPERMOST ON LAYING CONDITIONS. THIS PERCENTAGE IS ESSENTIALLY A JUNCTION OF THE NATURE OF THE CHALK SUBJECT TO VARIOUS DEGREES OF LOOSENING AND OF THE NUMBER AND NATURE OF HANDLING OPERATIONS. THE INVESTIGATIONS LED TO THE DEVELOPMENT OF EMPIRICAL TESTS, THE VIBRATORY CRUSHING TEST AND THE REPEATED COMPACTION TEST.]]></description>
      <pubDate>Sun, 21 Nov 2010 14:48:24 GMT</pubDate>
      <guid>https://trid.trb.org/View/1074913</guid>
    </item>
    <item>
      <title>STABILITY OF HIGH CHALK EMBANKMENTS</title>
      <link>https://trid.trb.org/View/1074912</link>
      <description><![CDATA[OBSERVATIONS AND STUDIES CARRIED OUT ON THE CHALK EMBANKMENT IN VAL-GUYON  ALONG THE A13 MOTORWAY ENABLED THE CAUSE OF THE OBSERVED SETTLEMENT AND CRACKS TO BE DISCOVERED. THOSE DISORDERS COULD NOT BE EXPLAINED WITH STANDARD THEORIES. IT WAS DEMONSTRATED THAT SETTLEMENT WAS CAUSED BY AN INCREASE IN DENSITY DUE TO THE TIME-RELATED WEATHERING LOW DENSITY CHALK BLOCKS. THIS COULD HAVE LED TO AN INCREASE IN PORE WATER PRESSURE AND IN THE POISSON'S RATIO OF THE CHALK. A STUDY OF STRESSES BY MEANS OF THE FINITE ELEMENT METHOD SHOWED THAT THOSE INCREASES COULD LEAD TO A DEVELOPMENT OF TENSILE STRESSES AT THE HEAD OF THE EMBANKMENT; THIS PHENOMENON COULD EXPLAIN THE LONGITUDINAL CRACKS OBSERVED. CALCULATIONS PERMITTED TO DEFINE THE INFLUENCE OF THE MECHANICAL CHARACTERISTICS OF CHALK THAT OF THE HEIGHT OF THE EMBANKMENT AND THE GRADIENT OF ITS SLOPE ON THE DEVELOPMENT OF SUCH CRACKS. RECOMMENDATIONS WERE PUT FORWARD FOR THE USE OF SOFT CHALK IN THE CONSTRUCTION OF EMBANKMENTS VARYING IN THEIR GEOMETRY.]]></description>
      <pubDate>Sun, 21 Nov 2010 14:48:23 GMT</pubDate>
      <guid>https://trid.trb.org/View/1074912</guid>
    </item>
    <item>
      <title>GEOLOGICAL CHARACTERISTICS OF CHALK IN THE PARIS BASIN</title>
      <link>https://trid.trb.org/View/1074911</link>
      <description><![CDATA[THE AUTHORS DESCRIBE THE PETROGRAPHIC CHARACTERSTICS OF CHALK, WHICH CONSISTS OF PRODUCTS OF ROCK WEATHERING AND MICROFOSSILS, OSTRACODS AND FORAMINIFERA WITHIN A MATRIX, MIXTURE OF NANNOFOSSILS AND VERY SMALL CALCITE FINES. THE LOOSE STRUCTURE OF THE MATRIX, OBSERVED WITH A SCANNING ELECTRON MICROSCOPE, EXPLAINS THE MECHANICAL BEHAVIOUR OF CHALK. A STUDY OF THE MICROFAUNA AND PALEOGRAPHY OF THE PARIS BASIN SHOWED STRATIGRAPHIC DIVISIONS, IN WHICH A CLASSIFICATION OF CHALK IS BASED: CHALK WITH DETRITAL TENDENCY AT THE EDGE OF THE BASIN AND CHALK WITH A HIGHT CACO3 CONTENT AT THE CENTRE OF THE BASIN. STRATIGRAPHIC AND PETROPHYSICAL DATA ENABLE GEOTECHNICAL PROBLEMS TO BE APPROACHED IN A MORE GENERAL WAY.]]></description>
      <pubDate>Sun, 21 Nov 2010 14:48:21 GMT</pubDate>
      <guid>https://trid.trb.org/View/1074911</guid>
    </item>
    <item>
      <title>STUDY OF EARTHWORKS ON THE A2 MOTORWAY, APPLICATION OF COMPACTION BY VIBRO-TAMPING TO THE EMBANKMENTS ALONG THE COMBLES-HORDAIN SECTION</title>
      <link>https://trid.trb.org/View/1074847</link>
      <description><![CDATA[THE EXECUTION OF EARTHWORKS ALONG THE A2 MOTORWAY HAD A GREAT INFLUENCE ON THE RATE OF PROGRESS OF THE CONSTRUCTION SITE. FAVOURABLE WEATHER CONDITIONS IN THE SUMMER OF 1971 WERE NOT REPEATED IN 1972, AND THE SOIL WAS FOUND TO BE IN A VERY UNSATISFACTORY CONDITION. INTENSIVE VIBRO-TAMPING SEEMED TO BE A POSSIBLE SOLUTION FOR SPEEDING UP THE CONSTRUCTION OF EMBANKMENTS AND COMPLETING THE PROJECT WITHIN THE ALLOCATED TIME. FOR THE FIRST TIME, THIS NEW TECHNIQUE WAS MONITORED BY MEANS OF MEASUREMENTS CARRIED OUT BY  A REGIONAL BRIDGE AND HIGHWAY LABORATORY (SAINT-QUENTIN).]]></description>
      <pubDate>Sun, 21 Nov 2010 14:46:43 GMT</pubDate>
      <guid>https://trid.trb.org/View/1074847</guid>
    </item>
    <item>
      <title>DIFFERED BEHAVIOUR OF ROCKS. INFLUENCE OF WATER</title>
      <link>https://trid.trb.org/View/1072651</link>
      <description><![CDATA[DIFFERED DEFORMATIONS IN SOME ROCKS HAVE A MARKED INFLUENCE OF THE LONG-TERM BEHAVIOUR OF UNDERGROUND STRUCTURES. IT IS PROPOSED TO STUDY THE DIFFERED BEHAVIOUR OF SOME SOFT ROCKS (CHALK, MARL) BY MEANS OF LONG-TERM CREEP  TESTS. THE FIRST PART OF THE STUDY WILL CONSIST OF THE DEVELOPMENT OF A TEST METHOD FOR UNIAXIAL AND TRIAXIAL STRESSES. A SPECIAL INVESTIGATION WILL BE MADE OF PROBLEMS ARISING FROM THE CONTROL OF PORE WATER PRESSURE DURING LONG-TERM TESTS AND FROM THE CONTROL OF CONFINING STRESSES. LABORATORY  TESTS WILL BE CARRIED OUT IN CONNECTION WITH OBSERVATIONS WHICH COULD BE  MADE IN SITU ON UNDERGROUND CONSTRUCTION SITES IN MARL (UNDERGROUND RAILWAY IN MARSEILLE) AND IN CHALK (ROBEC TUNNEL).]]></description>
      <pubDate>Sun, 21 Nov 2010 13:32:01 GMT</pubDate>
      <guid>https://trid.trb.org/View/1072651</guid>
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