GCU Consultants Sdn Bhd’s (a member of the Aurecon Group) role: Geotechnical Consultant for the Electrified Double Track Project spanning from Alor Setar to Padang Besar
Client: MMC – Gamuda Joint Venture Sdn Bhd
The Electrified Double Track Project (EDTP), which serves over 320 kilometres from Ipoh to Padang Besar in Malaysia, enables interstate travel via electrified trains in half the time as compared to lower speed diesel trains. The project has created a positive impact on the economy; it has boosted tourism and facilitated an increase in logistical services and business-related travel.
The construction of the Ipoh to Padang Besar tracks was completed in 2014. It was a part of the government’s plan to improve overall rail standards within the country and to create a network of rail infrastructure that will allow its people to travel safely, comfortably, and faster at an affordable price.
GCU, a member of the Aurecon Group, was appointed by MMC – Gamuda Joint Venture Sdn Bhd (MGJV) to plan, design and supervise detailed soil investigations, ground treatment schemes, retaining walls and railway track embankment including the track bed for two packages namely:
Package N1 – Arau to Padang Besar
Package N2 – Alor Setar to Arau
Spanning across a 66-kilometre stretch which sits on the Kedah rail line, the works included constructing the embankment for the electrified train till sub-ballast level, pile foundation for some of the road bridges and the construction of permanent retaining walls.
As the works were carried out within proximity of the existing operational line, GCU conducted the necessary condition assessments and planned a systematic schedule of works. This is to ensure the ground vibrations would not affect the operational line and to also prioritise the safety of those on site. GCU also checked all the temporary shoring works proposed by the Contractors to ensure safe working condition besides the adjacent live track.
Based on the detailed soil analyses and geological studies, zones of geotechnical models were developed to identify the degree of ground treatment works required at different areas.
From Arau to Padang Besar, reasonably good soil conditions allowed for less invasive ground treatments and construction of the rail formation. However, between Alor Setar to Arau, unconsolidated soft to very soft marine clay deposits up to 15m thickness were present below ground level. This posed challenges to the team due to the ground being highly compressible with low shear strength properties.
Under such condition, removal and replacement works and prefabricated vertical drains with surcharge preloading were carried out at shallow embankments and areas with weak subgrade soils. This reinforced the underlying ground and strengthened its ability to withstand the dynamic stress from the travelling trains over time.
For areas with higher embankment heights, stone columns with surcharge preloading and piled embankments treatments were implemented.
For the proposed design of the permanent retaining wall alongside the railway tracks, the team adopted multiple approaches to suit various ground conditions and the design includes cantilever reinforced concrete (RC) walls, contiguous bored piles walls and soil nailed walls.
Throughout the design and construction phases, GCU provided on-site design and technical support to MMC – Gamuda. The team also produced the drawings and specifications for all proposed geotechnical works and supervised the construction of all proposed ground related works including rail embankment, up until the sub-ballast formation level.
Unfortunately, you are using a web browser that Aurecon does not support.
Please change your browser to one of the options below to improve your experience.