Technical Integration and Railway Projects: The Earlier, the Better

Before a railway opens to the public, properly integrating all components, systems and subsystems is critical. This ensures the railway functions as expected and costly system failures can be avoided. With traditional approaches, integrating these elements usually begins near the end of a project’s lifecycle, making it difficult to keep the project on schedule. Railway integration—bringing people, programs, processes and technology together from the beginning of the project to form a single system—can help address this problem by ensuring technical integration occurs long before the railway is scheduled to open.

Technical integration is the process of connecting different subsystems from different entities on physical, data and technical levels. When designing a railway, we must create a system architecture that can be easily maintained and refined throughout the project lifecycle. System architectures serve as visual aids that enable engineers to understand and relate the system in a block diagram format. Each system architecture includes “levels” that provide more detail the deeper the architecture goes, resulting in a system breakdown structure that shows the relationship between the railway and its systems, subsystems and their components.

Successful railway projects establish a system design including system architectures, system descriptions, a system breakdown structure, system requirements and interface requirements. Interfaces are critical points for management in any large-scale railway project because they represent inherent weak points where one system depends on another for a physical element, functionality or technical information. Since teams are formed to develop system elements rather than their interfaces, they tend to focus on developing their knowledge and expertise around the element itself. Interfaces, on the other hand, are often the “gaps” where understanding is limited, scope is not well-defined, and ownership is contested. To ease this burden, a detailed, rigorous interface management plan needs to be put in place as soon as the system architecture and requirements are sufficiently defined. If properly followed, the design team can overcome many high-risk design issues, which often hinder a project’s verification efforts as it nears its final development stages. If not, delays and potential system failures can occur.

Consider this scenario: An interface management plan is developed at the beginning of a light rail transit project. The plan includes more than 400 interface points needing to be tracked, resolved and verified throughout the project’s lifecycle. The main contractor and the subcontractors agree to the plan and follow through with execution. This is a crucial step in any interface management plan, as a single party deviating from it can lead to project delays and increase the possibility of potential system failures. As interface issues are discussed and resolved through design changes, interface control documents are created to note the discussion and resolution of each item. The plan is widely utilized, and the project is on track to obtain verification during construction.

However, at the last minute, an interface regarding the provisioning of extra-long fence posts for closed-circuit television (CCTV) installation at gate locations is taken off the interface management plan due to a planning and timeline issue. This interface had been identified at a later stage in the design process while the civil engineering team was under pressure to deliver their design drawings in advance of the ready for construction stage. To speed up the development of this interface and keep the project on schedule, the construction contractor assures the design team the interface will be directly coordinated on-site with fence suppliers, instead of being fully developed in design drawings according to the interface management plan. All parties agree to this means of resolving the issue, and the interface status is set as "resolved." However, the project is restructured, and the construction contractor is replaced. Because the original contractor fails to adequately share their list of on-site coordination responsibilities with the new contractor, the extra-long fence posts are not provisioned. Ultimately, the issue does not become apparent until the fencing supplier notes it during on-site installation, delaying the project’s completion. This delay results in additional costs for the project delivery partner and could have easily been avoided if the interface management plan was followed.

Conversely, imagine the overhead contact system (OCS) design team using a similar interface for provisioning extra-long poles to facilitate CCTV placement. They are faced with the same tight deadlines as the civil fence designers and must issue their design prior to fully resolving the interface. However, the OCS team does not offload the responsibility to the construction contractor and close the interface. Instead, the interface remains open until a design change is issued for the placement of the CCTV poles. Only then is it set as “resolved.” This resolution leads to a smooth on-site installation which has been coordinated and tracked using the interface management plan, demonstrating the value of thorough interface management and clear documentation from the design phase through construction.

The lesson: By implementing technical integration in an open and collaborative manner at the start of a railway project and creating a clearly defined system architecture that is respected throughout the interface management process, we can ensure the right information is being used at all times, the project stays on schedule, and system design features are properly delivered.