<rss version="2.0" xmlns:atom="https://www.w3.org/2005/Atom">
  <channel>
    <title>Transport Research International Documentation (TRID)</title>
    <link>https://trid.trb.org/</link>
    <atom:link href="https://trid.trb.org/Record/RSS?s=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" rel="self" type="application/rss+xml" />
    <description></description>
    <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>
    </image>
    <item>
      <title>PRESENT PRACTICE IN SUBSURFACE DRAINAGE FOR HIGHWAYS AND AIRPORTS</title>
      <link>https://trid.trb.org/View/97121</link>
      <description><![CDATA[A TABULATION IS PRESENTED OF REPLIES TO A QUESTIONNAIRE PREPARED BY THE COMMITTEE ON SUBSURFACE DRAINAGE, HIGHWAY RESEARCH BOARD. NEARLY ALL REPLIES STATED THAT FAULTY SUBSURFACE DRAINAGE CAUSED PAVEMENT FAILURES, INCLUDING RUTTING AND SHOVING A FLEXIBLE PAVEMENT, PUMPING IN CONCRETE PAVEMENTS AND FROST HEAVES AND BOILS IN BOTH TYPES OF PAVEMENT. PRACTICALLY ALL REPLIES GAVE CLOGGING OF BACKFILL MATERIAL, AND SOMETIMES PIPE, AS THE CHIEF CAUSE OF SUBSURFACE DRAINAGE FAILURES. UNDER IMPROVEMENTS SINCE 1942, PRACTICALLY ALL REPLIES NOTED IMPROVED BACKFILL MATERIAL. THEIR SPECIFICATIONS NOW CALL FOR CONCRETE SAND, CLEAN BANK-RUN SAND, OR BANK-RUN GRAVEL (OR THE EQUIVALENT) FOR BACKFILL WITH OCCASIONALLY 1/2 OR 1-1/2-IN. STONE GIVEN AS AN ALTERNATE. ABOUT HALF THE ORGANIZATIONS USE EITHER A FILTER TEST OR THE VICKSBURG PIPING RATIO CRITERION FOR FILTER DESIGN. THE OTHERS MAKE NO TEST. THE ALMOST UNANIMOUS USE OF CLEAN, SANDY BACKFILL IS IN MARKED CONTRAST TO THE EARLIER PRACTICE WHERE THREE-FOURTHS OF THE STATES USED STONE OR SCREENED GRAVEL. PRACTICALLY ALL ORGANIZATIONS USE PERFORATED METAL PIPE AND TILE PIPE. SOME ALSO USE CONCRETE PIPE. AS WOULD BE EXPECTED, THE CHIEF USE OF UNDERDRAIN INSTEAD OF DEEP DITCHES OCCURS WHERE THE LATTER WOULD BE A TRAFFIC HAZARD. DEPTH OF PIPE INVERT OR DEEP DITCH VARIES BETWEEN 2 AND 6 FT. USUALLY IT IS ABOUT 2 FT. DEEPER THAN THE AVERAGE FROST PENETRATION UNDER A BARE PAVEMENT. ABOUT TWO-THIRDS OF THE STATES REPORT THAT SUBBASE IS CARRIED OUT TO FULL WIDTH OF SHOULDERS. THE BALANCE REPLIED THAT IT IS CARRIED ONLY TO 1 OR 2 FT. BEYOND EDGE OF PAVEMENT. TOTAL THICKNESS OF SURFACE, BASE, AND SUBBASE VARIES WIDELY, OF COURSE, WITH CONDITIONS OF FROST, SOIL, TRAFFIC, ETC. AND IS FROM 6 TO 32 IN. THICK. THE REPLIES ON SAND DRAINAGE WELLS SHOW THAT FOUR STATE HIGHWAY DEPARTMENTS HAVE USED THEM. REPLIES FROM FEDERAL AGENCIES INCLUDED MENTION OF THEM ON ABOUT FOUR DAMS OR DIKES AND THREE AIRPORTS. IN EACH CASE THE RESULTS WERE FAVORABLE. /AUTHOR/]]></description>
      <pubDate>Thu, 28 Apr 1994 00:00:00 GMT</pubDate>
      <guid>https://trid.trb.org/View/97121</guid>
    </item>
    <item>
      <title>OBSERVATIONS ON TILE DRAINAGE PERFORMANCE</title>
      <link>https://trid.trb.org/View/126859</link>
      <description><![CDATA[IN ARID AND SEMI-ARID CLIMATES, TILE MUST MAINTAIN THE PLANT ROOTZONE AS A LOW-SALT ENVIRONMENT. THROUGH EVAPOTRANSPIRATION, THE ROOTZONE SERVES TO CONCENTRATE SALTS IN THE SOIL WATER, AND THE TILE SYSTEM PROVIDES EGRESS FOR THE SALINE WATER BELOW THAT ROOTZONE. ENVELOPES ARE MATERIAL PLACED AROUND TILE TO IMPROVE WATER MOVEMENT FROM THE SOIL INTO THE TILE. FILTERS ARE ENVELOPES HAVING THE ADDITIONAL FUNCTION OF EXCLUDING LOOSE SOIL PARTICLES THAT MIGHT ENTER AND CLOG THE TILE. THE NEED FOR FILTERS IS DEMONSTRATED ONLY IN ALLUVIAL SOILS. PERIODIC FLUSHING OUT OF TILE APPEARS TO BE AN ALTERNATIVE TO USING FILTERS. MATERIALS CLOGGING TILE LINES HAVE BEEN IN THE SIZE RANGE OF 0.06 MM TO 0.12 MM. SATISFACTORY FILTER DESIGN CRITERIA ARE BASED ON THE STANDARD DEVIATION OF NORMALLY DISTRIBUTED PARTICLE SIZES IN A LARGE SAMPLE, AND THE WELL ESTABLISHED FILTER TO AQUIFER RATIO. FOR THE SIZE MATERIALS THAT HAVE BEEN FOUND TO CLOG TILE LINES, FILTER CRITERIA ARE GIVEN. A TECHNIQUE TO PROTECT TILE LINES DURING "SUBBING-IN" AND TO LESSEN ENVELOPE REQUIREMENTS IS DISCUSSED. /ASCE/]]></description>
      <pubDate>Mon, 24 Jan 1994 00:00:00 GMT</pubDate>
      <guid>https://trid.trb.org/View/126859</guid>
    </item>
    <item>
      <title>MODIFIED APPROACH TO TILE DRAIN DESIGN</title>
      <link>https://trid.trb.org/View/182237</link>
      <description><![CDATA[Hydraulic data of Kumb tile drainage scheme have been analysed.  Spacings of the drains have been estimated by various standard methods, viz.  Glover Dumm, Kraijenhoff-Maasland and Hooghoudt.  Authors have also developed a formula for spacing that gives the result which is close to the one obtained by Glover-Dumm formula. (Author)]]></description>
      <pubDate>Thu, 30 Dec 1982 00:00:00 GMT</pubDate>
      <guid>https://trid.trb.org/View/182237</guid>
    </item>
    <item>
      <title>ON-SITE LAND TREATMENT SYSTEMS FOR FREEWAY REST AREAS</title>
      <link>https://trid.trb.org/View/179488</link>
      <description><![CDATA[This study evaluates the effectiveness of existing on-site sewage treatment systems used at freeway rest areas in Michigan.  It also evaluates the effectiveness of land-treatment systems designed to polish and dispose of the partially treated effluents from septic tanks and lagoons.  The selection of the proper system or combination of systems to match the physical constraints of a particular site can ensure quality effluents and dispose of theem so that they will not harm the environment.  Tile drain field, seepage pits, seepage beds, sand filters, overland flow evapotranspiration systems, and a modified barriered landscape water renovation system were studied.  The parameters measured included total coliforms, fecal coliforms, total streptococci, fecal streptococci, biological oxygen demand, total organic carbon, total phosphorus, inorganic phosphate phosphorus, total Kjeldahl nitrogen, ammonium nitrogen, nitrite nitrogen, nitrate nitrogen, andd suspended solids.  (Author)]]></description>
      <pubDate>Sat, 30 Oct 1982 00:00:00 GMT</pubDate>
      <guid>https://trid.trb.org/View/179488</guid>
    </item>
    <item>
      <title>CONCRETE-POLYMER MATERIALS: USBR-BNL-AEC-OSW COOPERATIVE PROGRAM</title>
      <link>https://trid.trb.org/View/56445</link>
      <description><![CDATA[Contents: Introduction; Monomer survey - polymer-cement concrete studies; Process technology development - concrete composition; Test results on polymer-impregnated concrete (Polymer-impregnated concrete for ambient temperature applications, Polymer-impregnated concrete for desalting applications at temperatures up to 290F), Fundamental studies; Quality control - nondestructive tests; Applications development (Pipe applications, Precast tunnel supports and linings); Summary and conclusions; Bibliography.]]></description>
      <pubDate>Wed, 20 Sep 1978 00:00:00 GMT</pubDate>
      <guid>https://trid.trb.org/View/56445</guid>
    </item>
    <item>
      <title>DESIGN ASPECTS OF ROAD DRAINAGE</title>
      <link>https://trid.trb.org/View/26528</link>
      <description><![CDATA[RESEARCH HAS BEEN CARRIED OUT BASED UPON EXISTING KNOWLEDGE OF TILE DRAINAGE OF ROADS. IT IS MENTIONED THAT HIGH GROUND WATER LEVELS IN ROADS OCCUR MAINLY IN THE CLAY AND SILT SOIL PROFILES IN THE WESTERN PARTS OF THE NETHERLANDS AND OCCASIONALLY, UNDER SPECIFIC CONDITIONS, IN THE SANDY LOAM DEPOSITS IN THE EASTERN PARTS OF THE COUNTRY. BY MEANS OF A SPRINKLER INSTALLATION THE RELATION WAS ESTABLISHED BETWEEN THE AMOUNT OF PRECIPITATION ON THE ROAD AND THE GROUND WATER LEVEL IN THE SANDBED. IT APPEARED THAT EVEN BY LITTLE PRECIPITATION A RAPID RISE OF THE GROUND WATER-LEVEL OCCURRED PROBABLY DUE TO SMALL STORAGE CAPACITY AS A RESULT OF TRAFFIC COMPACTION. FROM INVESTIGATIONS INTO THE RELATION BETWEEN WATER CONTENT AND WATER SUCTION (PF-CURVE) ON ONE HAND AND WATER CONTENT AND STABILITY OF THE SANDS (C.R.B.- VALUE) ON THE OTHER HAND IT FOLLOWED THAT FOR SANDBEDS OF VERY HEAVILY LOADED ROADS IN THE NETHERLANDS A DEWATERING DEPTH OF 0,80 M WITH RESPECT TO THE TOP OF THE SAND SUBBASE IS REQUIRED. FOR DETERMINING THE NECESSITY OF A DRAINAGE SYSTEM IN ROADS, GENERALLY IN THE FORM OF A SANDBED TILE- DRAINAGE, A CALCULATION METHOD WAS DEVELOPED. HOWEVER, THIS CALCULATION-METHOD CAN ONLY BE APPLIED TO A ROAD PROFILE WITH SIDE DITCHES. TO ILLUSTRATE MORE COMPLICATED SITUATIONS SUCH AS VIADUCT DRAINAGE SYSTEMS, DRAINAGE OF ROADS IN URBAN AREAS, AND THE CASE OF UPWARD SEEPAGE, FOUR EXAMPLES OF DRAINAGE SYSTEM ARE INCLUDED.]]></description>
      <pubDate>Thu, 01 May 1975 00:00:00 GMT</pubDate>
      <guid>https://trid.trb.org/View/26528</guid>
    </item>
    <item>
      <title>DEPTH OF BARRIER AND WATER TABLE FALL IN A TILE DRAINAGE MODEL</title>
      <link>https://trid.trb.org/View/139653</link>
      <description><![CDATA[A laboratory model having a transparent photographable front and containing glass beads has been used for determining, under idealized conditions, the influence of a barrier on tile drainage, in regard to both rate of fall of the water table and tile discharge. Photographs of the modeled water table and the measured discharge as it varies with time are raw experimental data, and charts of dimensionless drainage parameters have been derived therefrom. The results show that changes in depth of a shallow porous medium markedly influence drainage. A critical depth occurs when the barrier is at a depth equal to one fifth of the drain spacing; then the barrier has negligible influence on rate of fall of the water table and on drain discharge. When steady rainfall (in the form of drops of glycerol) was applied, the water table arch at equilibrium was more curved for the higher rates of rainfall. Graphs of rainfall-intensity versus water table height were straight lines both for a position over the tiles and midway between tiles. The data reported here differ from other published data in that here a number of steady state rainfall conditions were used to establish initial conditions. Data were compared with theoretical work, and a good agreement was obtained.]]></description>
      <pubDate>Fri, 13 Dec 1974 00:00:00 GMT</pubDate>
      <guid>https://trid.trb.org/View/139653</guid>
    </item>
    <item>
      <title>SPECIFIC SURFACE OF HARDENED PORTLAND CEMENT PASTE AS DETERMINED BY SMALL ANGLE X-RAY SCATTERING</title>
      <link>https://trid.trb.org/View/139489</link>
      <description><![CDATA[Small-angle X-ray scattering was used to determine the specific surfaces of hardened portland cement pastes subjected to various treatments. Reasonably mature pastes yielded values of the order of 700 m2/g of ignited paste when examined in the original saturated condition.Driving to an intermediate relative humidity, P-drying, and D-drying reduce the surface areas to values of the order of 200 to 300 m2/g, but vacuum resaturation results in recovery of all the lost surface. Oven drying produces an additional loss in surface area, and in this case recovery on resaturation is not quite complete. The effect of w/c ratio appears to be minor, and pastes of hydrated C3S yield essentially the same surface areas as corresponding portland cement pastes. /AUTHOR/]]></description>
      <pubDate>Tue, 12 Nov 1974 00:00:00 GMT</pubDate>
      <guid>https://trid.trb.org/View/139489</guid>
    </item>
    <item>
      <title>INVESTIGATION OF CONCRETE PAVEMENT PUMPING /WITH DISCUSSION/</title>
      <link>https://trid.trb.org/View/105242</link>
      <description><![CDATA[THIS PAPER DESCRIBED THE INVESTIGATION OF THE PUMPING AT TRANSVERSE JOINTS IN CONCRETE PAVEMENT SLABS ON A PROJECT 4.39 MILES IN LENGTH ON U.S. 52 IN SCIOTO COUNTY, OHIO. THE SOILS SURVEY MADE PRIOR TO GRADING OPERATIONS SHOWED THAT ON SOME SECTIONS THE PREDOMINATING SOIL WAS HIGH IN SILT CONTENT AND COULD BE CLASSIFIED IN THE A-4 GROUP. IT WAS CONSIDERED NECESSARY TO COVER THESE AREAS WITH SUITABLE GRANULAR MATERIAL TO A DEPTH OF 18 INCHES AND PROVIDE TILE DRAINAGE. THE PAVEMENT WAS BUILT WITHOUT REINFORCING OF LOAD TRANSFER DEVICES. OBSERVATIONS WERE MADE OF SLAB DEFLECTIONS UNDER MOVING LOADS. PUMPING WAS FOUND TO BE MUCH MORE EXTENSIVE AND SEVERE OVER THE AREAS WHERE NO GRANULAR MATERIAL WAS USED. ON THE PLAIN CONCRETE SECTION PUMPING WAS MORE SEVERE AT CONTRACTION JOINTS OF THE PREMOLDED TYPE. THE SEVERITY ON THE REINFORCED SECTION WAS ABOUT THE SAME FOR EXPANSION AND CONTRACTION JOINTS. ON THE PLAIN CONCRETE SLABS WITHOUT GRANULAR SUBBASE, 2 PERCENT OF THE EXPANSION JOINTS AND 52 PERCENT OF THE CONTRACTION JOINTS WERE PUMPING. ON THE PLAIN CONCRETE SLABS PLACED ON GRANULAR SUBBASE 1.5 PERCENT OF THE EXPANSION AND 16 PERCENT OF THE CONTRACTION JOINTS WERE PUMPING. ON THE REINFORCED SECTION, 71 PERCENT OF THE EXPANSION JOINTS AND 91 PERCENT OF THE CONTRACTION JOINTS WERE PUMPING. ON MOST OF THE WORK, THE GRADATION OF THE BACKFILL FOR THE TILE DRAINS WAS FROM THE 3/4-INCH TO NO. 4 SIZES. IT WAS OBSERVED THAT THESE DRAINS SILTED UP BADLY. THE CONCLUSIONS ARE: (1) A SUBBASE COMPOSED OF SUITABLE GRANULAR MATERIAL WILL APPRECIABLY REDUCE THE PUMPING AT JOINTS IN CONCRETE PAVEMENTS; (2) SMALL SIZE BACKFILL AGGREGATE WILL EXTEND THE USEFUL LIFE OF TILE DRAINS; AND (3) LOAD TRANSFER DEVICES PREVENT EXCESSIVE PERMANENT DEFORMATION AT THE JOINTS BETWEEN CONCRETE SLABS AFTER PUMPING STARTS. /AUTHOR/]]></description>
      <pubDate>Mon, 29 May 1972 00:00:00 GMT</pubDate>
      <guid>https://trid.trb.org/View/105242</guid>
    </item>
    <item>
      <title>LEACHING OF A SURFACE LAYER OF SODIUM CHLORIDE INTO TILE DRAINS IN A SAND-TANK MODEL</title>
      <link>https://trid.trb.org/View/126400</link>
      <description><![CDATA[A SERIES OF EXPERIMENTS WAS CONDUCTED TO STUDY THE LEACHING OF NACL THROUGH TILE DRAINS FROM A SURFACE LAYER OF SALINIZED SAND IN A SAND-TANK MODEL. THE EFFECTS OF TWO RECHARGE RATES, THREE SALINITIES IN THE SALTED-SAND LAYER, AND THREE DRAIN SPACINGS WERE EVALUATED. EACH EXPERIMENT WAS CONDUCTED WITH A STEADY- STATE, ARCH-SHAPED WATER TABLE MAINTAINED BY RECHARGE FROM A BATTERY OF CAPILLARY TUBES THAT GAVE A UNIFORM INFILTRATION OVER THE MODEL. ALL THE SALT WAS LEACHED FROM THE MODEL. THE SALT WAS DYED BLUE SO THAT THE LEACHING FRONT COULD BE PHOTOGRAPHED. THE SALINITY OF THE TANK SOLUTION AND OF THE DRAINAGE WATER WAS MEASURED AT REGULAR INTERVALS. INTENSE FINGERING DEVELOPED IN ALL EXPERIMENTS IN WHICH A SALINIZED LAYER WAS USED. FINGERING CAUSED A RAPID AND ERRATIC REDISTRIBUTION OF SALT WITHIN THE MODEL AND AN ERRATIC VARIATION IN THE SALINITY OF THE DRAINAGE WATER UNTIL ABOUT 1 PORE VOLUME HAD DRAINED. THE HIGHER THE INITIAL SAND SALINITY, THE MORE INTENSE WAS THE FINGERING, THE LONGER WERE THE FINGERS, AND THE HIGHER WERE THE FINGER VELOCITIES. THE BEHAVIOR OF THE FINGERING TRANSITION ZONE WAS CONTROLLED BY THE INTERACTION BETWEEN THE DENSITY GRADIENTS AND THE HYDRAULIC GRADIENT; THIS LATTER DEPENDS ON THE RECHARGE RATE AND THE DRAIN SPACING. THE SALINITY OF THE OUTFLOW DRAINAGE WATER ROSE QUICKLY TO A PEAK AND THEN DECLINED ALMOST AS QUICKLY FOR A SHORT PERIOD, AFTER WHICH IT REDUCED MORE GRADUALLY. AFTER ABOUT 1 PORE VOLUME HAD DRAINED, THE SALINITY OF THE DRAINAGE WATER DECLINED EXPONENTIALLY IN ALL SALINIZED EXPERIMENTS. EXPERIMENTAL CURVES FIT CLOSELY TO AN EXPONENTIAL RELATIONSHIP EXCEPT INITIALLY AND WHERE FINGERING RESULTED IN ERRATIC VARIATIONS. /AUTHOR/]]></description>
      <pubDate>Tue, 16 May 1972 00:00:00 GMT</pubDate>
      <guid>https://trid.trb.org/View/126400</guid>
    </item>
    <item>
      <title>PRINCIPLES OF UNDERDRAINAGE DESIGN IN THE BELORUSSIAN S.S.R.</title>
      <link>https://trid.trb.org/View/125142</link>
      <description><![CDATA[CONTENTS: BASIC PRINCIPLES AND METHODS OF HYDROTECHNICAL RECLAMATION WORK ON MARSHES AND BOGGED-UP MINERAL SOILS TYPES AND CATEGORIES OF DRAINAGE WATER-REGULATION AND AERATION DRAINAGE TILE, WOODEN AND MOLE DRAINS DRAINAGE DESIGN AND COMPUTATION DRAINAGE NETWORK AND ARRANGEMENT IN PLAN DRAIN DEPTH, SPACING AND SLOPES MODULUS OF DRAINAGE RUNOFF AND DRAIN DIAMETERS HYDRAULIC COMPUTATION OF DRAINS LENGTH OF DRAINS JUNCTION OF DRAIN LINES STRUCTURES ON THE DRAINAGE NETWORK OUTLETS, INSPECTION WELLS, DROPS, REGULATING SLUICES EXECUTION OF DRAINAGE WORK LAYING OF MOLE AND SLOT DRAINS, AERATION DRAINS, EARTHENWARE TILE DRAINS, WOODEN DRAINS.]]></description>
      <pubDate>Sat, 10 Apr 1971 00:00:00 GMT</pubDate>
      <guid>https://trid.trb.org/View/125142</guid>
    </item>
  </channel>
</rss>