Project Description

The Gautrain Rapid Rail project in South Africa between Johannesburg, Pretoria and Johannesburg International Airport, is currently the largest rapid rail transit project under construction in the world, at a cost of more than 25 billion Rand (approx 2.5 billion Euros). The Gautrain is a public– private partnership between the Gauteng provincial government and Bombela. The whole construction project is being undertaken by a Canadian – French – British - South African consortium.

Construction began in 2006 on the first link in the new network, which will run from the O.R.Tambo Airport outside the city to the Sandton District of Johannesburg and this is scheduled for completion by June 2010 – just in time for the fans arriving for the next FIFA Football World Cup. The rest of the project with five more stations and their links is scheduled for completion in 2011.

The total new twin line, rapid rail network will be more than 80 kilometres in length and the new ‘Gautrain’ will travel at speeds of up to 160 km/hr, plus much of its route is through the city and its suburbs will be underground, further reducing congestion and dramatically cutting the current journey times.

Project Requirements

The bridges and raised sections of the railway are being built using segmental bridge construction methods, involving match-cast, precast concrete bridge sections that are assembled and pre-stressed together using post-tensioning techniques.

This placement, tensioning and subsequent waterproofing of the tendons is greatly enhanced by the use of a segmental adhesive to lubricate the adjacent surfaces during the final assembly, transfer load evenly across the joints (when cured) and seal to the joints between the units against water ingress.

The technology is regulated internationally with the Federation Internationale du Beton (FIB) standards laid down for the nature and performance of the adhesive. The joint venture engineers also wanted to be able to continue working with an FIB approved adhesive that could be used over the wide temperature range, which could occur on site during the 4-year construction period. ie through every season - even in the extremes of the low possible and high temperatures.

Finally, the joint venture insisted on to obtaining security of supply, to avoid any construction delays and they wanted to buy at the lowest possible cost due to the large volumes required (in total more than 65,000 litres).

Sika Solutions

Sika have a full range of segmental bridge adhesives tested and approved to FIB standards, with the most extensive worldwide references of any manufacturer. This includes products suitable for application at different temperatures covering the widest possible range from 4°C to more than 60°C. Plus importantly the Sika Technicians could use and adapt this worldwide experience to support the application on site in South Africa.

Additionally, through Sika’s modern manufacturing facilities for these materials in Durban, South Africa, it was possible to provide the necessary surety of supply, thus avoiding the necessity for expensive imports or excessive stocks on site, and all therefore at the lowest possible cost.

To date the climate has been moderate during the periods of segment assembly and Sikadur®-31 SBA Grade S-02 has been used for all of the joints so far on the project, but additional grades can quickly be made if temperatures change in future. The adhesive is applied by hand at a nominal 3mm layer thickness, to achieve a sealed bond line after post-tensioning of around +/- 0.5mm.

Sika Products

In addition the following Sika product was used in the project

  • Sikadur®-31 SBA

Check out more information about Sika products in the African market

Project Participants

The Bombela Consortium including: Bombardier - based in Montreal with trains produced in the UK
RATP – the operator of the Paris metro
Murray & Roberts – The Leading South African Civil Engineers
Bouygues – the French International contractor
Strategic Partnership Group – Black economic empowerment group
Project Managers: Sika South Africa, Wayne Smithers, Paul Adams, Shaun Saxby, Niall Wilde
Applicator: VSL