Early Developments in Railroads

The inaugural railway, known as the Wollaton Wagonway, was established in 1603 in Britain, connecting Wollaton and Strelley in Nottinghamshire. Built with wooden rails and iron sleepers, it was one of approximately 50 similar constructions over the years. Small stones surrounded the sleepers to secure them and create a path for people or horses transporting wagons along the track. Rails typically measured about three feet long and were laid on common sleepers without joints. Curved tracks were achieved by angling adjacent rails.

In 1767, the first iron rails were laid at Darby Works in Coalbrookdale. However, the weight of steam locomotives soon proved too much for these rails. In 1804, Richard Trevithick's engine, the Peny-y-Darren, broke the track due to its excessive weight. In response, engineers developed iron rails mounted on stone sleepers, secured with cast iron chairs. Unfortunately, the rigidity of these iron rails led to issues as they lacked the flexibility needed to accommodate the movement of steam locomotives.

To improve drainage, track layers were built with a slight slope, and rubber matting was introduced to help reduce noise and vibration.

Traditional Track Framework

The conventional method of constructing tracks involves flat-bottomed steel rails that are either laid on or secured to timber or pre-stressed concrete sleepers, with crushed stone ballast supporting them. In areas with heavy rail traffic, continuously welded rails are employed, attached to sleepers with base plates, often utilizing rubber or plastic pads for added resilience.

Historically, softwood timber sleepers and jointed rails were common in the 20th century. While this construction method remains prevalent on secondary and tertiary lines, some countries have adopted alternative techniques.

In North America and Australia, flat-bottomed rails were typically fastened to sleepers with dog spikes through flat tie plates. In contrast, British and Irish railroads used bullhead rails secured in cast-iron chairs spiked to the sleepers. Although the heavy and costly bullhead rails have been replaced by flat-bottomed rails in Britain, they still exist on the national rail system, sidings, and heritage railways.

The transition to flat-bottomed rail in Britain was pioneered by the London, Midland, and Scottish Railway in 1936, although prior lines had experimented with it.

Railroad Maintenance and Innovations

A significant challenge of traditional track structures is the ongoing maintenance required to ensure proper surfacing and alignment. Issues such as weak subgrades and poor drainage can inflate costs. Ballastless track systems provide a solution to these challenges, functioning similarly to highway infrastructure with a continuous reinforced concrete slab supporting the rails via resilient pads. This system, however, comes with high initial costs and requires existing tracks to be closed for extended periods during installation.

Despite these drawbacks, ballastless tracks can lead to lower long-term costs due to reduced maintenance needs. Such systems are often utilized for new high-speed routes and are common in rapid transit and rubber-tired systems.

Continuous longitudinally supported track, which offers support along the rail's length, has been found to be more costly to maintain than traditional cross-sleeper systems. Some bridges still utilize this type of track. Innovations such as Balfour Beatty's embedded slab track, which employs a rounded rectangular rail profile, have emerged in recent years.

In this video, learn how to stay safe around train tracks and avoid accidents.

Rail Classification and Lengths

The weight of a rail determines its classification, impacting its ability to support heavier loads and higher speeds. In North America and the UK, rail is graded by weight per yard, typically ranging from 115 to 141 lb/yd, while European standards employ kilograms per meter.

Advancements in manufacturing have allowed for longer rail lengths, improving structural integrity. For example, the Pennsylvania Railroad produced rails weighing 155 lb/yd, and modern techniques have led to lengths exceeding 393 feet.

Discover essential tips and tricks for laying tracks in Railroads Online!