Gulf Construction Online - BASF has the formula for better grouting

Concrete Technology

Detail showing duct and post-tension strands prior to grouting.

BASF has the formula for better grouting

Flowcable, the most commonly-used post-tension grout additive in the Arabian Gulf, and Masterflow 190, BASF's latest addition to its post-tension grouting range, have established a track record in the region and continue to be used on some of the most prestigious projects in the region, according to BASF Construction Chemicals.

01 April 2008

Grout is used in post-tensioning to completely fill all voids and spaces between the high-yield steel strands in the post-tension duct.

This encapsulation provides the necessary protection by preventing corrosion products such as moisture and air-borne chlorides from penetrating and corroding the steel strands.
The grout should, therefore, be fluid and stable for the duration of the grouting operation to ensure complete filling, he points out.
Some of the important parameters and their function, for a successful post-tension grout are detailed in Table 1.
Table 2 shows the property-specified values, together with typical results achieved from grout containing Flowcable additive.
The addition of the correct water content is critical to ensure that the specified property is achieved. Flowcable, is added to Ordinary Portland Concrete (OPC) at a rate of six per cent by weight of cement. Water is added to achieve a w/c ratio of 0.36. Too little water and the grout will be too stiff to flow, too much water will result in the grout bleeding and separating.
Masterflow 190, the latest addition to BASF's post-tension grouting range, builds on the proven performance of Flowcable while improving its ease of use. This premium grade, pre-blended, ready-to-use product is suitable for all post-tension applications; it is easy to use, cost-effective and quality assured.
Some of the major projects where Masterflow 190 is currently being used are: Saadiyat Island Crossing, in Abu Dhabi, Al Futtaim Carillion Sports City and the Dubai Light Rail in the UAE.
“The decision by Ed Zublin (contractor), Parsons International (consultant) and the TDIC (Tourism Development and Investment Company) to use Masterflow 190 on the prestigious and highly-technical 1.5-km-long Saadiyat Island Crossing confirms the position of BASF Construction Chemicals as the first choice for post-tension grouting solutions,” says Ian Waddell, technical service manager (Arabian Gulf region), BASF Construction Chemicals.
BASF Construction Chemicals, considered to be the world’s largest manufacturer of construction chemicals, has had a long and successful association with the post-tension industry.
“From our production facility in the Dubai Investment Park, we manufacture a range of technically superior grouts and grout additives specifically designed to impart the high performance requirements necessary for this demanding function in the hot and extreme conditions we experience in the Middle East,” he says.
“In addition to its superior product offering, BASF also has a dedicated technical service team who will carry out on-site evaluation trials to determine optimum addition values and who also provide ongoing site support throughout application, thus it a complete solution provider,” Waddell concludes.