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The concrete grade ties in use since 1965, in mainline have provided evidence of longevity, maintenance requirements and other fixtures to improve road conditions. To eliminate transition problems from wood to concrete or vice versa, making a total concrete tied railroad will improve conditions. In 1969, the Florida East Coast Railway began an agressive program of installing concrete crossing ties in all grade crossings. A potential crossing of special ties designed to support the rail and traffic with specially prepared concrete slabs for support of highway traffic is a proven improvement. Concrete bridge ties for use on open deck bridges were first designed and installed in 1965. A railroad has three problem areas: grade crossings, bridge approaches and switches. The design of the concrete switch tie completes the entire rail-road tie need converted to concrete. The tie conceived in 1979, and perfected in 1983, was first installed in 1984, is still being modified for manufacturing ease and standardization. The tie is performing as planned with no adjustment on maintenance required after installation and retaining the basic theory of grade ties, bridge ties and crossing ties that restricting rail movement is the key to controlling alignment and surface. The impact is thereby easily dealt with. The heft of the entire turnout allows for less wear and tear and extends the life of the assembly. The Railroad Concrete Crosstie Corp. also manufactures security/sound barrier walls, prefabricated buildings, mile posts, prefab battery boxes, fibre-optic cable junction boxes and prefab bridge head walls. Concrete is the strong, durable material for fixtures of a working railroad.

Today, at least ten transit properties in the United States and Canada use pretensioned monoblock or reinforced two-block concrete ties. Pretensioned monoblock concrete ties have been manufactured by the long-line method. Reinforced two-block ties have been manufactured in individual forms using the "instant demolding" method. High strength concrete and pre-stressing tendons, and reinforcing and structural steel conform-ing to current standards have been specified for the production of concrete ties. Quality control programs that address material properties, production operations, and tolerances are required to assure consistency in quality and performance. In a concrete tie rack, the fastening system maintains gage, maintains alignment, restrains longitudinal rail movement, provides resilience, and assures electrical insulation. The ballast provides supporting strength and resistance to the loads imposed on track, resil-ience, stability, and drainage capabilities. The ability of the ties and fasteners to provide their intended functions is evalu-ated by laboratory tests. The tests evaluate tie strength at rail seat and at tie center, the bond between the concrete and prestressing tendons or reinforcing steel, the ability of the fastener to provide adequate longitudinal and lateral restraint and to resist uplift forces, the serviceability of the tie and fastener components under service-simulated loads, and the ability of the tie-fastener system to provide adequate electrical resistance and impedance. A concrete tie track provides techni-cal, economical, and environmental advantages by using improved fastening systems and eliminating components with high mainten-ance requirements. A concrete tie track would generally yield a lower life-cycle cost than a wood tie track and provide better service operation and increased safety.

The Vancouver SkyTrain guideway structures employ concrete beams precast in full-span lengths, with vertical and horizontal curvature and variable superelevation to follow the precise track trajectory. Tangent and curved structures, special structures, and structures containing spans of up to 45 m utilize the same trapezoidal beam. Approximately 300 inserts were placed in the deck and sidewalls of each beam during concreting operations. The trackwork, the linear induc-tion motor, and other subsystems were attached directly to the precast beams through these inserts without a second concrete pour. Construction of the Vancouver SkyTrain was preceded by simul-taneous development of vehicle and guideway technologies and the construction of a 1.1-km elevated guideway section that was used to demonstrate the operational characteristics of the system and confirm its constructability. This paper describes the guideway structure, reviews its design and construction, and presents an overview of the construction schedule and costs.

This paper describes the manufacture of 1040 prestressed concrete trapezoidal box girder guideway beams for the 14.8 km long dual-lane aerial guideway for the Vancouver Advanced Light Rapid Transit Project. The guideway beams are up to 36 m in length and weigh up to 100 t. In order to achieve the extremely tight tolerances dictatedbythe direct fixation ofrunning and linear induction motor railstotheprecastbeams, a sophisticated forming system was utilized to produce b ea ms with continuously varying vertical and horizontal alignment and super-elevation. Ahigh-precision jigging system was developed to cast in threaded inserts for attachment of the track hardware, and a thorough quality control program for dimensional and material control was instituted to ensure compliance with the construction specifications. Thedesignofthe first pumped concrete placing system to be used in a North American precast plant is described, as well as details of the plant layout, movable shelters, hoisting equipment and steam curing system utilized. Stripping, storageandtransportationoftheserrassivebeamstothe siteovercity streets at night is described. Details of the plant and field post-tensioning operations which were included inthebeamsupplycantract are also provided.

The Long Island Rail Road (LIRR) in conjunction with New York State Department of Transportation (NYSDOT) in December 1980, completed a grade crossing eli.mination project in Long Island. To provide a solution to problems of costly track maintenance, two parallel, 1.13 mile (1.82 km) long slab tracks were constructed. Unl ike convent ional track with cross ties ancl ballast, this slab track consists of a continuously reinforced concrete slab supported on an asphalt-treated subbase and compacted subgrade to help determine adequacy of design and suitability of this type of construction for other projects, a field testing program was developed and implemented by contracting with Construction Technology Labora-t o r i e s . The paper describes advantages of slab track systems, design details, construct i on t echni ques and sequence, inst rument at i on, test results and findings.