The Kallang-Paya Lebar Expressway (KPE) is part of the Land Transport Authority's plan to develop a comprehensive road network for Singapore. When completed, the KPE will facilitate traffic flow from the north-east, such as Hougang, Serangoon, Sengkang and Punggol to the city areas. Together with the North-East MRT line, the KPE will help relieve traffic congestion along the busy north-east traffic corridor.
Built at an estimated cost of S$1.8 billion , the KPE will be a dual 3-lane expressway, and stretch over 12km from the Tampines Expressway (TPE) in the north-east to the East Coast Parkway (ECP) in the south. About 9km of the expressway, from ECP to Defu Lane 3, will be built entirely underground as road tunnels, using the cut-and-cover method. This will make it the longest underground expressway in South-east Asia.
Six ventilation buildings with specialised ventilation equipment are located along the expressway to ensure that fresh air can be pumped in and foul air extracted along the tunnel route. The whole tunnel will be under continuous surveillance and real-time information of tunnel conditions will be transmitted to the control centre. There will also be an integrated traffic and plant monitoring system. Special equipment will be installed in the tunnel to allow communications for mobile phones and radios.
Construction on the expressway started in the year 2001, and is expected to be completed in 2008.
Process Control System
CNA provides the process control system for the Tunnel Ventilation and Environment Control Systems. To enhance the safety of the tunnels for road users, the design of the Local Sequential Controller (LSC) system is based on a fail-safe, hot-redundant PLC (Programmable Logic Controller) system. The contract requires the PLC control system to meet the requirements of SIL2, and to be designed and developed in accordance with the requirements of IEC 61508 (Functional safety of Programmable Electronic Systems).
System Description
The Tunnel Ventilation System (TVS) controls the air quality in the tunnel to an acceptable level under normal and congested mode of operation, and at the same time, to provide an effective means of smoke control during emergency conditions. A separate staircase pressurization system will pressurize the escape staircases during emergency.
The Environmental Control System (ECS) provides a comfortable and safe environment for personnel and equipment in the ventilation buildings.
The Tunnel Ventilation System (TVS) monitors and controls the tunnel ventilation fans under normal, congestion, maintenance and emergency modes.
The LSC panel controls the indoor VRV (Variable Refrigerant Volume) air-conditioning units and outdoor PCUs (Pre-cool Units) via high-level Interface. |
