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    <title>Transport Research International Documentation (TRID)</title>
    <link>https://trid.trb.org/</link>
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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>
    </image>
    <item>
      <title>TRUCKERS WANT QUALITY, BUT NOT TOO MUCH OF IT</title>
      <link>https://trid.trb.org/View/130817</link>
      <description><![CDATA[THE XRL TRUCK TRACTOR WAS DEVELOPED LIKE AN AIRPLANE. THE VEHICLE WAS BROKEN DOWN INTO A SERIES OF SYSTEMS, AND EACH SYSTEM WAS ATTACKED WITH THE GOAL OF ELIMINATING THE UNEXPECTED BREAKDOWN. THE NEW TRUCK HAS IMPROVED WIRING PROTECTION, ADDITIONAL SEAT COMFORT FOR THE DRIVER, IMPROVED COOLING SYSTEM, AUTOMATIC LUBRICATION AND IT IS EASY TO REPAIR. A GUARANTEED MAINTENANCE PROGRAM IS SOLD WITH THE TRUCK IN WHICH THE COMPANY SUPERVISES AND PERFORMS ALL MAINTENANCE AT A SET FEE PER MILE. THE LOW MAINTENANCE COST COMPARED TO THAT OF A STANDARD TRUCK WILL MORE THAN PAY FOR THE DIFFERENCE IN COST.]]></description>
      <pubDate>Sat, 09 Mar 2002 00:00:00 GMT</pubDate>
      <guid>https://trid.trb.org/View/130817</guid>
    </item>
    <item>
      <title>CUSHIONED CONCRETE TIES FOR ULTRA-SMOOTH TRAINS</title>
      <link>https://trid.trb.org/View/97177</link>
      <description><![CDATA[A NEW TRACK DESIGN MADE OF CONTINUOUS WELDED RAIL, SECURED ON CUSHONED CONCRETE CROSSTIES BY ELASTIC SPRING FASTENERS, IS EXPECTED TO PROVIDE COMUTERS WITH A WHISPER SMOOTH TRAIN RIDE. THE CONCRETE CROSSTIES HAVE ALREADY WON SIGNIFICANT APPROVAL IN EUROPE AS AN ECONOMICAL, HIGHLY EFFECTIVE WAY TO CONVERT AN ORDINARY RAILROAD INTO A HIGH SPEED RAILWAY SYSTEM. THE CROSSTIES RESEMBLE BARBELLS MADE UP OF TWO CONCRETE BLOCKS CONNECTED BY A STEEL TIEBAR. SECONDARY REINFORCEMENT CONSISTS TOP AND BOTTOM LONGITUDINAL GRIDS THAT CONTAIN TEN REINFORCING BARS AND A ROUND SPIRAL CAGE. THE NEW DESIGN PROVIDES A TRACK THAT HAS 97% FEWER JOINTS AND ONE THAT WILL LAST 33% LONGER THAN CONVENTIONAL TRACK. MAINTENANCE COSTS ARE REDUCED BY ABOUT 50% PER TRACK MILE.]]></description>
      <pubDate>Thu, 24 Nov 1994 00:00:00 GMT</pubDate>
      <guid>https://trid.trb.org/View/97177</guid>
    </item>
    <item>
      <title>ELECTRONICS RUNS THE SHOW IN BAY AREA TRANSIT SYSTEM</title>
      <link>https://trid.trb.org/View/130685</link>
      <description><![CDATA[THE BAY AREA RAPID TRANSIT (BART) SYSTEM IS AN URBAN RAPID TRANSIT SYSTEM DESIGNED TO RELIEVE HIGHWAY CONGESTION. THE SYSTEM WILL INCLUDE 33 PASSENGER STATIONS AND 75 MILES OF DOUBLE-TRACK RAILROAD, BELOW GROUND AND ABOVE, IN SAN FRANCISCO, ALAMEDA, AND CONTRA COSTA COUNTIES. TO COMPETE WITH AUTOMOBILES, BART CALLED FOR AN AVERAGE SPEED OF 50 MPH, INCLUDING 20-SECOND STATION STOPS. AT TIMES, HEADWAY WILL BE ONLY 90 SECONDS FOR TRAINS RUNNING BETWEEN STATIONS AT 80 MPH, WITH ROUTES CONVERGING AND DIVERGING. THE DEGREE OF CONTROL NEEDED FOR SAFETY UNDER THESE CONDITIONS WILL BE PROVIDED BY AN AUTOMATIC TRAIN CONTROL SYSTEM. THE SYSTEM DEVELOPED BY WESTINGHOUSE ELECTRIC CORP. USES A CENTRAL COMPUTER WITH A SPECIAL-PURPOSE COMPUTER IN EACH HEAD-END CAR TO PICK UP SIGNALS FROM WAYSIDE EQUIPMENT. MAJOR COST- REDUCING FACTORS IN THE SYSTEM WERE THE DESIGN OF A MULTIPLEX DIGITAL SIGNAL SYSTEM. THE WESTINGHOUSE SYSTEM IS DESCRIBED. THE SYSTEM PERFORMS TWO DUTIES AT ALL TIMES: (1) TRAIN PROTECTION BY SPEED CONTROL BETWEEN STATIONS, AND (2) DECELERATION, BY ANOTHER CONTROL PROGRAM SUPERIMPOSED AT STATION APPROACHES, TO STOP THE TRAIN WITHIN 6 INCHES OF TARGET AT THE PLATFORM. THE TRAIN DOORS THEN OPEN AUTOMATICALLY FOR A PERIOD FIXED BY THE CENTRAL COMPUTER'S SCHEDULE-CONTROL LOOP. THE YARD DESIGN SYSTEM DESIGNED BY PHILCO-FORD AUTOMATICALLY TAKES OVER WHEN THE TRAIN-CONTROL COMPUTER SWITCHES A TRAIN FROM THE MAIN LINE TO A TRANSFER TRACK. A COMPUTER OVERSEES ALL STEPS OF THE YARD OPERATION. COST OF THIS SYSTEM IS KEPT DOWN BY THE USE OF SOLID-STATE FAILSAFE LOGIC INSTEAD OF CONVENTIONAL VITAL RELAYS FOR ALL SWITCHING EXCEPT FROM THE TRANSFER TRACK. A TYPICAL LOGIC MODULE IS THE DUAL JK FLIP-FLOP, BASED ON AEROSPACE TECHNOLOGY, THAT REDUCES THE SYSTEM TO HALF THE COST AND ONE-THIRD THE SIZE OF THE CONVENTIONAL RELAY SYSTEM IT REPLACES. THE AUTOMATIC YARD CONTROL SYSTEM IS DESCRIBED AS WELL AS A MECHANIZED FARE COLLECTION SYSTEM DEVELOPED BY IBM. SPECIFICATIONS FOR THE POWER SUPPLY AND TRAIN PROPULSION SYSTEMS CALL FOR: (1) FOUR 150-HP DC DRIVE MOTORS PER CAR, WITH SOLID-STATE CHOPPER CONTROL, (2) FOUR COLLECTOR SHOES PER CAR, CONTACTING A 1000-V DC RAIL, AND (3) A COMPOSITE CONTACT RAIL OF STEEL AND ALUMINUM, WITH NEGATIVE RETURN THROUGH RUNNING RAILS. A NEW COMPOSITE CONTACT RAIL AND A LIGHTWEIGHT COLLECTOR SHOE PROVIDE BETTER POWER TRANSMISSION TO A HIGH-SPEED VEHICLE AT MUCH LESS COST THAN THE CONVENTIONAL EQUIPMENT. THE NEW RAIL IS A COMPOSITE STEEL AND ALUMINUM DESIGN DEVELOPED BY KAISER ALUMINUM, WITH A PLYWOOD COVER ENCAPSULATED IN FIBER GLASS.]]></description>
      <pubDate>Fri, 02 Sep 1994 00:00:00 GMT</pubDate>
      <guid>https://trid.trb.org/View/130685</guid>
    </item>
    <item>
      <title>EXPERTS DISAGREE ON WHAT IS NEEDED IN AUTO SAFETY</title>
      <link>https://trid.trb.org/View/113284</link>
      <description><![CDATA[THE INCREASED INTEREST IN SAFETY AND NATIONAL SAFETY STANDARDS FOR AUTOMOBILES HAVE BROUGHT INTO FOCUS SOME OF THE PROBLEMS WHICH BESET THIS FIELD. AS IN MANY OTHER AREAS, THE EXPERTS DO NOT AGREE. ONE GROUP SAYS THAT MANY IMPROVEMENTS IN DESIGN ARE NOT BEING APPLIED RAPIDLY ENOUGH, BUT THE OTHER GROUP FEELS THAT NEW STANDARDS WILL HAVE TO BE BASED ON A DEMONSTRABLE NEED, BACKED BY MORE RESEARCH AND MORE DATA. SOME AUTHORITIES BELIEVE THAT EXISTING FEDERAL STANDARDS ARE IN AN EVOLUTIONARY STAGE AND WILL IMPROVE. WHAT IS NEEDED NOST, ACCORDING TO ONE GROUP IS SOME KIND OF YARDSTICK WHICH WILL PROVIDE STANDARD-MAKERS WITH A PRIORITY SYSTEM. APPLIED TO CAR DESIGN, THIS YARDSTICK COULD MEASURE THE EFFECTIVENESS OF SAFETY STANDARDS AND THE HARDWARE DESIGNED TO MEET THEM. ALSO NEEDED ARE BETTER MATHEMATICAL MODELS OF VEHICLES, DRIVER-VEHICLE INTERACTION, AND CRASH- SAFETY EFFECTIVENESS. FROM THESE MODELS WILL BE DEVELOPED FULL SIZED EXPERIMENTAL CARS FOR FURTHER TESTING.]]></description>
      <pubDate>Sat, 18 Jun 1994 00:00:00 GMT</pubDate>
      <guid>https://trid.trb.org/View/113284</guid>
    </item>
    <item>
      <title>ULTRASONICS: INTENSE ENERGY WITH A DELICATE TOUCH</title>
      <link>https://trid.trb.org/View/106668</link>
      <description><![CDATA[NEW APPLICATIONS IN ULTRASONICS ARE SUGGESTED IN MANUFACTURING OPERATIONS FOR ALL KINDS OF FORMING, MACHINING, JOINING, AND FINISHING OPERATIONS ON ANY METAL (EVEN THE REFRACTORIES), AT ROOM TEMPERATURE, WITH NO BURRS OR FRACTURES, AND WITH NO INDUCED STRESSES. THERE IS ALREADY WIDE SPREAD USE OF ULTRASONICS IN CLEANING JOBS, MACHINING OF CERAMICS, NONDESTRUCTIVE INSPECTION AND TESTING, AND THE ASSEMBLY OF PLASTIC PARTS. THE VARIOUS EFFECTS ACHIEVED BY ULTRASONICS ARE NOT COMPLETELY UNDERSTOOD. RESULTS OF ALL APPLICATIONS OF ULTRASONICS TO METAL WORKING ARE MORE EVIDENT THAN THE REASONS THAT IT WORKS. IMPROVEMENTS OVER OTHER FORMS OF METAL WORKING INCLUDE LOWERED TOOL LOADING, BETTER METAL FLOW, BETTER SURFACE FINISH, CHANGES IN RECRYSTALIZATION BEHAVIOR AND THEIR FORMATION TEXTURE AND CHANGES IN WORK HARDENING. ACCORDING TO ACCEPTED HYPOTHESES, THE EFFECTS ARE BROUGHT ABOUT BY TWO DIFFERENT ASPECTS OF HIGH-FREQUENCY SOUND WAVES: THE SURFACE EFFECT AND THE VOLUME EFFECT. THESE EFFECTS ARE DISCUSSED. DESIGN OF AN ULTRASONIC SYSTEM IS DESCRIBED FROM THE VIEWPOINT OF THE THREE BASIC SYSTEM COMPONENTS: AN ELECTRO-MECHANICAL TRANSDUCER (GENERATOR), A CONNECTING BODY (COUPLING), AND A TOOL, OR HORN. NONDESTRUCTIVE TESTING IS DESCRIBED USING HIGH-FREQUENCY SOUND WAVES IN VARIOUS APPLICATIONS. THE RANGE OF ULTRASONIC APPLICATIONS IS BEING EXTENDED BY NEW HIGHER- POWERED EQUIPMENT AND BY NEW EFFICIENCY THAT MAY EVENTUALLY PRODUCE TWICE THE RESULT WITH THE SAME POWER.]]></description>
      <pubDate>Sat, 18 Jun 1994 00:00:00 GMT</pubDate>
      <guid>https://trid.trb.org/View/106668</guid>
    </item>
    <item>
      <title>TWO-YEAR STUDY YIELDS DATA FOR EVALUATING COATED STEEL CABLE</title>
      <link>https://trid.trb.org/View/106565</link>
      <description><![CDATA[WIRE CABLES JACKETED WITH NYLON, POLYOLEFIN, VINYL, AND URETHANE PLASTICS WERE SUBJECTED TO TEMPERATURE CYCLING UNDER VARIOUS LOADS, FATIGUE CONDITIONS, AND CHEMICAL ENVIRONMENTS. THE PLASTIC CONTRIBUTES MORE THAN CORROSION RESISTANCE' FATIGUE LIFE IS INCREASED AND WEAR RESISTANCE IS IMPROVED. DATA ARE PRESENTED ON CYCLIC LIFE, CUT-THROUGH RESISTANCE, ABRASION RESISTANCE, AND TEMPERATURE RATINGS. /ARTICLE/]]></description>
      <pubDate>Wed, 15 Jun 1994 00:00:00 GMT</pubDate>
      <guid>https://trid.trb.org/View/106565</guid>
    </item>
    <item>
      <title>DEVELOPMENTS TO WATCH: A SUBWAY TRAIN THAT CARRIES ITS OWN LOADING PLATFORM</title>
      <link>https://trid.trb.org/View/130680</link>
      <description><![CDATA[A SUBWAY TRAIN THAT CARRIES ITS OWN LOADING PLATFORM IS THE LATEST IN A SERIES OF IDEAS FROM FRANCE. THE NEW TRAIN LOOKS LIKE AN ORDINARY SUBWAY TRAIN SPLIT LENGTH-WISE DOWN THE CENTER. ONE SIDE, THE SIDE AWAY FROM THE UNLOADING AREA, CARRIES THE USUAL SEATS FOR PASSENGERS. THE OTHER SIDE HAS NO SEATS. IT'S THE LOADING AND UNLOADING PLATFORM. THERE ARE DOORS BETWEEN THE TWO SECTIONS, SO EACH SECTION CAN BE SEALED OFF. THE TWO SECTIONS HOOK UP AND TRAVEL TOGETHER BETWEEN STATIONS; AND, WHILE IN TRANSIT, THE DOORS OPEN BRIEFLY SO PASSENGERS WHO WANT TO LEAVE THE TRAIN AT THE NEXT STATION CAN MOVE INTO THE UNLOADING SIDE. WHEN THE TRAIN GETS TO A STATION, THE UNLOADING SIDE SEPARATES AND STOPS TO UNLOAD. THE OTHER SIDE DOES NOT STOP. IT GOES ON AND HOOKS UP WITH ANOTHER UNLOADING SECTION FURTHER ALONG. THE UNLOADING SECTION WAITS FOR THE NEXT LOADED SECTION TO COME ALONG, THEN HOOKS UP WITH IT AND GOES ON. THUS THE TRAIN ACCOMMODATES BOTH LOCAL AND EXPRESS RIDERS. SOCIETE AUTOMATISME ET TECHNIQUE HAS PRODUCED A WORKING SCALE MODEL, AND ACCORDING TO A BRITISH REPORT, THE AUTHORITIES IN MARSEILLE ARE PLANNING TESTS. /ARTICLE/]]></description>
      <pubDate>Thu, 09 Jun 1994 00:00:00 GMT</pubDate>
      <guid>https://trid.trb.org/View/130680</guid>
    </item>
    <item>
      <title>CITY NOISE: DESIGNERS CAN RESTORE QUIET, AT A PRICE</title>
      <link>https://trid.trb.org/View/130502</link>
      <description><![CDATA[THE NOISE GENERATED BY THE MODERN SOCIETY IS PRODUCING ADVERSE SOCIAL EFFECTS. TECHNICALLY, NOISE CONTROL IS POSSIBLE FOR ANY PRODUCT. ECONOMICALLY, DESIGN FOR NOISE REDUCTION ALWAYS INCURS A PENALTY SPACE, WEIGHT, OR ADDED MATERIALS. IN 1965, NEW YORK STATE ENACTED THE FIRST ENFORCEABLE STATE LAW GOVERNING TRUCK NOISE, SETTING A LIMIT OF 88 DB MEASURED AT 50 FEET. THE NEW YORK LAW IS REGARDED AS ABOUT THE BEST IN THE COUNTRY. HOWEVER, IT WAS DESIGNED TO CONTROL TRUCK NOISE ON THE THROUGHWAYS, AND TRUCKS GOVERNED BY IT ARE ALLOWED TO PASS THROUGH NARROW CITY STREETS WHERE PEOPLE LIVE OR WORK. MOST URBAN NOISE POLLUTION COMES FROM OUTSIDE THE HOME, FROM BEYOND THE CONTROL OF THE CITY DWELLER. IN NOISE-CONTROL LEGISLATION, EUROPE IS AHEAD OF THE UNITED STATES. ENFORCEABLE LIMITATIONS ARE IN EFFECT IN MOST INDUSTRIALIZED COUNTRIES. MANY EUROPEAN COUNTRIES STRICTLY REGULATE THE HOURS WHEN CONSTRUCTION WORK CAN BE CARRIED ON. THE FOLLOWING TYPES OF NOISE ARE DISCUSSED: JET ENGINES, AIRCRAFT NOISE, AIRPORT NOISE, TRUCK TRAFFIC, GARBAGE TRUCKS, TRANSIT SYSTEMS, CONSTRUCTION WORK, AND AIR CONDITIONERS. THE BEST METHOD OF NOISE CONTROL IS AT THE SOURCE, WITH MUFFLERS, QUIETER MECHANISM, OR DAMPING. WHEN THAT IS NOT POSSIBLE, A BARRIER CAN BE PLACED IN THE SOUND PATH. DESIGN ENGINEERS ARE EXPLORING ALL OF THESE AVENUES FOR THE DAY WHEN THE PUBLIC WILL DEMAND QUIET.]]></description>
      <pubDate>Thu, 02 Jun 1994 00:00:00 GMT</pubDate>
      <guid>https://trid.trb.org/View/130502</guid>
    </item>
    <item>
      <title>THE PLANS ARE SET FOR BUSES TO RUN ON STEAM</title>
      <link>https://trid.trb.org/View/130674</link>
      <description><![CDATA[FOUR QUIET, SMOG-FREE BUSES WILL BE OPERATING IN THE SAN FRANCISCO BAY AREA NEXT YEAR, IF A FEDERAL GRANT IS APPROVED FOR A STEAM-BUS DEMONSTRATION PROJECT. IT IS BELIEVED THAT THESE BUSES WILL BE CHEAPER, QUIETER, AND MUCH MORE SMOG-FREE THAN CONVENTIONAL MODELS. STEAM ENGINES WILL PROVIDE NOISELESS, VIBRATION-FREE, LOW-MAINTENANCE, POWERFUL, AND CLEAN URBAN MASS TRANSPORTATION. SINCE A STEAM-ENGINE CAR DRIVING AT 60 MPH GETS 20 TO 22 MILES ON A GALLON OF KEROSENE, ECONOMIC TRANSPORTATION WILL BE PROVIDED. A DESCRIPTION IS PRESENTED OF A STEAM CAR THAT HAS BEEN DESIGNED.]]></description>
      <pubDate>Thu, 26 May 1994 00:00:00 GMT</pubDate>
      <guid>https://trid.trb.org/View/130674</guid>
    </item>
    <item>
      <title>GRAVITY-VACUUM TRANSIT GETS BOOST TOWARD REALITY</title>
      <link>https://trid.trb.org/View/130678</link>
      <description><![CDATA[A COMPREHENSIVE STUDY WAS MADE OF THE GRAVITY-VACUUM TRANSIT (GVT) FOR CITY USE. THE GVT CONCEPT EMPLOYS GRAVITY AND PARTIAL VACUUM TO PROPEL CYLINDRICAL TRAINS AT AIRCRAFT SPEED THROUGH STEEL TUBES EMBEDDED IN TUNNELS DEEP UNDERGROUND. THE TUBES ARE EVACUATED BY PUMPS LOCATED NEAR THE STATIONS. THE TRAINS ARE SUPPORTED AND GUIDED BY INDIVIDUALLY MOUNTED WHEELS THAT RIDE HIGH UPON RAILS. THE TUBES ARE SPRING-MOUNTED AND DIP FOR GRAVITY BOOST BETWEEN STATIONS. GRAVITY FURNISHES ROUGHLY TWO-THIRDS OF THE TOTAL ENERGY REQUIRED TO ACCELERATE GVT TRAINS. ATMOSPHERIC PRESSURE PROVIDES THE REMAINING THIRD OF THE ENERGY. THE COMBINED DRIVING FORCE OF A GVT TRAIN BUILDS UP TO ROUGHLY 170 TONS, THE SUM OF THE PNEUMATIC FORCE AND THE GRAVITY FORCE. AN AMAZING ASPECT OF THIS SYSTEM IS THAT PASSENGERS ARE ACCELERATED IN A WAY THEY CANNOT FEEL.]]></description>
      <pubDate>Thu, 26 May 1994 00:00:00 GMT</pubDate>
      <guid>https://trid.trb.org/View/130678</guid>
    </item>
    <item>
      <title>SONAR SYSTEM UNSNARLS KINKS IN MIXING CEMENT AT THE PLANT</title>
      <link>https://trid.trb.org/View/97147</link>
      <description><![CDATA[A CEMENT-MIXING PLANT HAS INSTALLED AN AUTOMATIC, ULTRASONIC MEASURING SYSTEM TO SOLVE A MEASUREMENT PROBLEM CREATED BY EFFECTS OF WEATHER EXTREMES. HEAT AND COLD, RAIN AND SNOW AGGRAVATED THE CAKING OF MATERIALS ON PADDLE WHEELS USED TO CHECK MATERIAL LEVELS IN THE CONCRETE-BATCH- MIXING FACILITY. THE ULTRASONIC MEASURING SYSTEM'S SOLID- STATE ELECTRONIC EQUIPMENT IS PACKAGED SO IT IS UNAFFECTED BY MOISTURE AND TEMPERATURE CHANGE. THIS ELIMINATES THE PROBLEM OF CAKING AND THE CATWALK CLIMB IS NO LONGER NEEDED BECAUSE THE NECESSARY PERIODIC INVENTORY READINGS OF MATERIAL LEVEL ARE NOW TAKEN AT THE CONTROL ROOM ON THE GROUND. THE SYSTEM CONSISTS OF A TRANSDUCER AND A SOLID- STATE ELECTRONICS UNIT CONNECTED BY COAXIAL CABLE. THE TRANSDUCER IS MOUNTED ABOVE THE MATERIAL TO BE MEASURED AND THE ELECTRONICS CONTROL UNIT WITH A READ-OUT METER IS IN A CONTROL ROOM. THE TRANSDUCER PROJECTS AN ULTRASONIC SIGNAL AND RECEIVES AN ECHO FROM THE TOP OF THE MATERIALS. A PRECISE TIMING CIRCUIT MEASURES THE TIME IT TAKES THE SIGNAL TO TRAVEL FROM THE SENSOR AND BACK. THIS TIME VALUE IS CONVERTED INTO VOLTAGE DISPLAYED ON A METER IN UNITS OF SPECIFIC APPLICATION. THE SYSTEM INCLUDES SIX TRANSDUCER HEADS WITH A MANUAL SELECTOR SWITCH THAT ALLOWS THE OPERATOR TO SELECT ANY OF SIX BINS FOR A LEVEL READING. THE LEVEL MONITOR SAMPLES EACH BIN TO DETERMINE WHICH IS FULL AND WHICH NEEDS ADDITIONAL INGREDIENTS. COMPLETE CONTROL OF EMPTYING AND REFILLING THE BINS CAN BE MAINTAINED FROM THE CONTROL ROOM.]]></description>
      <pubDate>Thu, 26 May 1994 00:00:00 GMT</pubDate>
      <guid>https://trid.trb.org/View/97147</guid>
    </item>
    <item>
      <title>JUST ADD WATER TO POLYESTER TO MAKE A STRUCTURAL MATERIAL</title>
      <link>https://trid.trb.org/View/106659</link>
      <description><![CDATA[A LOW-COST, FAST-SETTING STRUCTURAL MATERIAL THAT MAY SUPPLANT WOOD, PLASTER, CONCRETE, AND CERAMICS IN SOME APPLICATIONS WAS ANNOUNCED AT LAST MONTH'S SPI REINFORCED PLASTICS CONFERENCE IN WASHINGTON. THE MATERIAL IS BASED ON POLYESTER RESINS DISPERSED IN WATER THAT CAN MAKE UP EVEN 90% OF THE TOTAL MIX. THESE WATER-EXTENDED PLASTICS WERE DEVELOPED BY ADM CHEMICALS DIV. OF ASHLAND OIL & REFINING CO., MINNEAPOLIS. ADM SELLS THE SPECIAL POLYESTER RESINS, UNCURED. THE USER ADDS WATER AND CONVERTS THE MIXTURE TO A SOLID BY APPLYING CATALYSTS AND PROMOTERS. BLENDING THE RESIN WITH THE WATER TO FORM AN EMULSION CREATES TINY DROPLETS, 2 TO 5 MICRONS IN DIAMETER, BUT THERE IS NO TRACE OF MOISTURE IN THE CURED MATERIAL. THE WATER IS TRAPPED IN CELLS WITHIN THE CROSS-LINKED POLYMERIC STRUCTURE. AT THE HIGHEST PROPORTION OF WATER (90% OF CONTENT), THE CURED MATERIAL IS MORE LIKE A PLASTIC FOAM THAN A SOLID PLASTIC. ADM CHEMISTS SAY THE STRONGEST MATERIALS ARE MADE WITH 50% TO 60% WATER. THEY AREN'T HIGH-STRENGTH MATERIALS, BUT THEY HAVE FOUR TIMES THE COMPRESSIVE STRENGTH OF WOOD AND RATE ABOUT THE SAME AS WOOD IN TENSILE AND FLEXURAL PROPERTIES. FINAL COSTS, OF COURSE, DEPEND ON HOW MUCH WATER IS BLENDED WITH THE POLYESTER. ADM SAYS A 60%-WATER MATERIAL SHOULD COST ABOUT 9 CENTS A LB OR $4/CU. FT. /ARTICLE/]]></description>
      <pubDate>Fri, 13 May 1994 00:00:00 GMT</pubDate>
      <guid>https://trid.trb.org/View/106659</guid>
    </item>
    <item>
      <title>LAB TESTS SHOW SALT-SEEDING COULD FREE AIRPORTS OF FOG</title>
      <link>https://trid.trb.org/View/113562</link>
      <description><![CDATA[CORNELL AERONAUTICAL LABORATORY IS HAVING SOME SUCCESS WITH SEEDING CLOUDS WITH ORDINARY TABLE SALT TO DISBURSE FOG. THE METHOD IS BASED ON CONDENSING THE MOISTURE DROPLETS IN THE FOG BY DROPPING SALT CRYSTALS TO COLLECT THE DROPLETS INTO LARGE ENOUGH DROPS SO THAT VISIBILITY IS IMPROVED. A LIGHT AIRCRAFT COULD BE SENT ALOFT AS SOON AS THE FOG BECAME THICK ENOUGH TO IMPAIR A PILOT'S VISION SIGNIFICANTLY. THE PLANE WOULD CARRY CONTAINERS OF SODIUM CHLORIDE OF THE PRECISE GRAIN SIZE NEEDED. THE CHEMICAL WOULD BE RELEASED OVER THE RUNWAY APPROACHES TO DRIFT DOWN THROUGH THE FOG. SINCE THE SALT IS HIGHLY HYGROSCOPIC, IT WOULD ATTRACT THE MINUTE DROPLETS OF WATER AS IT FELL TO THE GROUND. THE AIR OVER THE RUNWAY WOULD THEN CONSIST OF DROPS OF WATER. THIS SOLUTION IS RESTRICTED TO THE PROBLEM OF WARM FOG ONLY.]]></description>
      <pubDate>Sun, 01 May 1994 00:00:00 GMT</pubDate>
      <guid>https://trid.trb.org/View/113562</guid>
    </item>
    <item>
      <title>ROLL-ON PLASTIC ROAD IS BOON TO HEAVY MILITARY TRANSPORT</title>
      <link>https://trid.trb.org/View/97137</link>
      <description><![CDATA[A ROAD THAT UNROLLS LIKE A RUG IS MADE OF GLASS-REINFORCED POLYESTER RESIN AND IS THE LATEST THING IN MILITARY TRANSPORTATION. IT IS DESIGNED FOR MOVING HEAVY VEHICLES ACROSS SANDY BEACHES AND SOFT GROUND IN AREAS WHERE HEAVILY LOADED VEHICLES WITH HIGH-PRESSURE TIRES ARE QUICKLY BOGGED DOWN. TESTS BY THE U.S. MARINE CORPS SHOW THAT THE PLASTIC ROAD CAN BE APPLIED IN ALMOST ANY KIND OF WEATHER, ON ANY TERRAIN THAT THE BULLDOZER CAN TRAVERSE. THE ROAD APPLICATOR IS TOWED BY A BULLDOZER, WHICH DRAGS A BLADE TO FLATTEN THE ROAD SURFACE. IN LESS THAN AN HOUR THE FIBER-GLASS HARDENS TO PROVIDE A ROAD SURFACE CAPABLE OF SUPPORTING HEAVY MILITARY VEHICLES.]]></description>
      <pubDate>Thu, 28 Apr 1994 00:00:00 GMT</pubDate>
      <guid>https://trid.trb.org/View/97137</guid>
    </item>
    <item>
      <title>ANEROBIC ADHESIVE GRIPS LIKE A VISE IN SECONDS</title>
      <link>https://trid.trb.org/View/106838</link>
      <description><![CDATA[AN ANEROBIC, TWO-COMPOND ADHESIVE THAT CURES IN TWO OR THREE MINUTES AT ROOM TEMPERATURE HAS BEEN DEVELOPED BY LOCTITE CORPORATION USING THE ADHESIVE, STEEL-TO-STEEL BONDS HAVE A 3,000-PSI TENSILE SHEAR STRENGTH EQUIVALENT TO THAT OF A HEAT-CURED EPOXY ADHESIVE. BECAUSE OF ITS TWO-COMPONENT SYSTEM, THE LOCTITE ADHESIVE DOES NOT REQUIRE PREMIXING. THE ADHESIVE SETS HARD ONLY WHEN DEPRIVED OF AIR. BECAUSE IT IS SLIGHTLY FLEXIBLE, MINUTE BOND 312 HAS BETTER FATIGUE AND IMPACT PROPERTIES THAN OTHER, MORE BRITTLE ADHESIVES. IN PROPERTIES, PERFORMANCE, AND COST IT IS SIMILAR TO EASTMAN CHEMICAL'S 910 ADHESIVE, A CYANOACRYLATE, WHICH BONDS ALMOST ANY NON-POROUS SURFACE AND GIVES BOND STRENGTHS UP TO 5,000 PSI. BOTH OF THESE ADHESIVES ARE RATHER LOW IN VISCOSITY SO THAT COST PER APPLICATION IS USUALLY LOW. NEITHER ADHESIVE IS RECOMMENDED FOR BONDING LARGE AREAS BECAUSE OF THEIR QUICK SETTING TIMES.]]></description>
      <pubDate>Thu, 21 Apr 1994 00:00:00 GMT</pubDate>
      <guid>https://trid.trb.org/View/106838</guid>
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