Escape from the chaos and heat of Kuala Lumpur's streets into the quiet, air-conditioned concourse of the new Sentral Station, and the serenity is striking. A vast expanse of granite enclosed under three traditional Malaysian domes provides the backdrop for a huge video entertainment screen and numerous digital information boards.
Everything is spotlessly clean.
But the calm and beauty of the station's interior belies the months of intense construction work required to reach this stage, and indeed work is still in progress outside.
KL Sentral stands on a 28.8ha site in Brickfields, about 1.5km from the city centre, and is being built to replace the existing station, constructed by the British during colonial days. Contractor EKD joint venture, led by Dragages Malaysia Berhad, was awarded the £170M project by client Kuala Lumpur Sentral Station in March 1997. The scope of works included the station and associated track works, three decks to support commercial developments, a maintenance depot for the state railway operator and 4km of access roads.
By any standards, construction of the Sentral Station scheme was a major undertaking. In addition to the station building itself the contract includes delivery of a new goods depot and three additional structures. Precinct A, to the west of the station, is to support four future office towers. Precinct F, to the north, will support two hotels. A multi-purpose auditorium completes the development.
But working in and around an operational marshalling yard with three electrified railway lines running through it dramatically increased the challenge facing EKD.
To allow the station building to be constructed, the three operational tracks had first to be diverted. Each line was rerouted separately over a period of months and with each diversion more of the site was freed up for construction work.
Work was only permitted over the live lines for a few hours each night when the 25kV catenary system feeding the trains could be disconnected. Until the diversions were completed the lines were enclosed beneath protective steel formwork. A fourth railway track, the PLRT (Putra Light Rail) which passes through the station on an elevated bridge, was also operational throughout construction. A steel tunnel structure had to be built around it so work could proceed.
A depot already existed on the site, providing maintenance and storage facilities for train operator KTMB. It was vital that KTMB should retain a facility to service its rolling stock and the new depot structure was built and partially handed over before the old shed was demolished.
Further track re-laying was called for to allow the operator entry to the new depot. A track slab design was used to reduce maintenance. Elsewhere on the site concrete sleepers on a traditional ballast track bed are used.
Timber sleepers have been used on the turnouts.
KTMB took full delivery of the completed depot in March.
Raised maintenance platforms in the new depot allow staff to clean the trains while troughed track allows engineers to work under them.
The station building itself is composed of two reinforced concrete structures spanned by a massive wave-shaped steel truss roof. Underneath, the platforms' combined length comes to over 1km.
Precinct F, supporting two new hotels, involved the construction of a 19,000m 2deck and two massive raft foundations - the foundations alone required 18,000m 3of concrete. Precinct A includes four rafts which will support the transfer deck for four future high rise buildings.
Precinct A was dropped from the contract and later reinstated.
As a result, construction had to take place above the three newly relocated live railway tracks.
Self-supporting precast concrete beam shells were launched across the tracks at night during the catenary system isolation period. Partially fabricated reinforcement cages were then dropped in by three crawler cranes allowing steel fixers to complete them during the following day. The beam shells were supported by steel trusses for the first beam concrete pour.
Once the concrete had cured the trusses were removed, leaving a self-supporting monolithic concrete structure. Hollow core slabs were launched between the beams to form the deck.
Precinct A was completed in June.
Assembling the workforce to tackle the gargantuan construction project proved as great a challenge as any other. Apart from the 200 Dragages staff employed in a supervisory role the rest of the operatives on site were subcontracted. Some 500 workers had to be drafted in from Pakistan to get around the shortage of local labour.
With all the live tracks running through the site, safety has been of paramount importance. During 16 months of peak activity more than 2,300 workers were on site, and all had to be educated about the potential dangers of working around a live railway. Yet over the entire three year construction period no fatalities were recorded.
Stringent safety rules were put in place at the start of the contract, and anyone in breach of them was thrown off site.
Every operative had a safety induction, and all subcontractors with more than 20 staff were required to have an approved safety officer.
Picking up the pieces
Probably the biggest problem the contractor had to overcome was a halt in construction work half way through the project.
As South East Asia's economic 'flu' took hold in Malaysia progress was affected, leading to an agreed suspension of the project between mid-July 1998 and January 1999.
Kuala Lumpur is scattered with projects that have started but due to cashflow crises have been abandoned.
After nearly a year of inactivity, restarting construction proved difficult. 'Many of the staff had changed, and we had to alter our methods every few months because of design amendments when parts of the project were omitted and then reinstated, ' recalls project director Jean-Noel Foulard. And the confidence of suppliers hit by cashflow problems also had to be regained.
Who s who, what s what
Client: Kuala Lumpur Sentral Station (MRCB Group) Main contractor: Dragages Malaysia Berhad as leader of joint venture Contract value: £170M Concept design: Kisho Kurokawa & Associates Architects: LPT (Liang Peddle Thorp) and MAA (station and depot) Client representative: Bovis Lend Lease.
Meinhardt (station and depot structure);
Robert Benaim (auditorium deck structure);
Norman Disney & Young (mechanical and electrical);
The new station is a transport hub for four main services: KTM Intercity services; KTM Komuter services; PLRT Light Rail; ERL Express Rail Link between KL, Putra Jaya and the new international airport.
Total surface area: 145,000m 2Total built up area: 242,000m 2Station: 110,000m 2Depot: 40,000m 2Precinct F: 19,000m 2Precinct A: 33,000m 2Auditorium: 36,000m 2Total quantity of concrete:
246,400m 3Number of piles: 2,600 Tracks: 18km Roads: 4km Imported granite: 31,000m 2