Skip to main content

Speed hardening system improves tunnel construction

BASF claims that its latest innovation will help improve efficiency in tunnel construction operations. Developed by BASF's Construction Chemicals division the new Crystal Speed Hardening system (CSH) is an advanced admixture technology aimed directly at the tunneling market.
February 14, 2012 Read time: 2 mins
The new concrete concept from BASF will help cut curing times
2645 BASF claims that its latest innovation will help improve efficiency in tunnel construction operations. Developed by BASF's Construction Chemicals division the new Crystal Speed Hardening system (CSH) is an advanced admixture technology aimed directly at the tunneling market. This product offers increases in efficiency for concrete casting, both for precast segments and cast in-situ linings. The fast-curing concept allows the removal of formwork at an earlier stage of the casting process and increases productivity. The product can shorten the length of time that formwork or shuttering has to be kept in position or by reducing the number of sets of formwork required. In addition to supporting efficiency, the system helps reduce CO2 emissions, optimises material use and meets high quality specifications according to the firm. It does so by providing high early strength development whilst balancing the requirement for an optimum mix through the use of more binding material and reduced clinker content.

The CSH concept uses a new hardening accelerator, X-SEED, to boost early strength development by modifying the action mechanism of cement hydration. X-SEED is made of suspended CSH-seeding crystals: the material added is of the same nature as the final hydration products from the cement reaction with water. As the suspended crystals are considerably smaller than microsilicas, the surface is much more beneficial for accelerating the crystal growth during the early stages of concrete hardening. The product has already been tried and tested in a number of tunneling trials. The abbreviation CSH also refers to calcium silicate hydrates; the cement hydration products responsible for the compressive strength of concrete. Hydration speed depends on the chemical composition of clinker and other cementitious materials. To simplify the science, by using BASF's X-SEED admixtures, a liquid suspension of synthetic crystal seeds on the nano scale, the growth of calcium silicate hydrate crystals is significantly accelerated.

For more information on companies in this article

Related Content

  • All-new road markings on world’s highways
    June 28, 2013
    Road marking manufacturers have many innovative new products either currently being used on major highways or set to be made available within the next couple of years. Guy Woodford reports. Daan Roosegaarde, an artist, and Hans Goris, a manager at Dutch construction and infrastructure firm Heijmans, are developing intriguing new products for the road markings market. One innovation involves painting road markings with glow-in-the-dark paint.
  • Innovative new drainage solutions will help keep roads free from water
    October 2, 2014
    An array of new technologies will help optimise road drainage and minimise flooding risks - Mike Woof reports In the UK the specialist contractor Lanes Group has carried out extensive inspection work of the drainage systems for the M6 toll route around the city of Birmingham. A powerful zoom camera has been used to carry out the inspection work for Midland Expressway, which operates and maintains the 43km-long motorway, running from Coleshill to Cannock.
  • New tests, new technology, new users: why materials testing is a growing market
    February 7, 2017
    A look back at some of the developments this year, and a look ahead to what may come next reveals the increasing use of materials testing. New technology and new ways to process and analyse data will drive change even further - Kristina Smith reports For materials testing equipment manufacturers, constant change is business as usual. New tests emerge, new standards are written and new practices spread around regions and the world. There are also new materials to deal with: bitumen modified with polymers
  • Advances in concrete paving materials
    July 9, 2012
    Innovations in materials technology, as well as machines, could provide a major boost to the concrete paving sector - Mike Woof reports Development of new material technologies for the concrete paving sector continues apace and the latest innovations could provide the biggest boost for this market in many years. High performance cementitious material (HPCM) is an innovative concept that has been developed and tested for road surfacing applications as part of a project in which the UK's Transport Research La