Page 1

1RQVKULQNFHPHQWLWLRXVJURXWIRUXQGHUZDWHULQVWDOODWLRQV8VHVConbextra UW is used for free flow or pumped groutingapplications underwater or in tidal zones. There will be nosignificant wash-out of the cement phase. Applicationsinclude bridge columns, quay pillars, concrete piling,slipways and dams.

$GYDQWDJHV No risk of significant wash-out of cement phase

when placed underwater Displaces water effectively Gaseous expansion system compensates for

shrinkage and settlement in the plastic state High early and ultimate strength and exceptional

resistance to freeze-thaw cycling ensure durability ofthe hardened grout

Chloride free Pre-packaged needing only on-site addition of water

'HVFULSWLRQConbextra UW is supplied as a ready to use powder. Theaddition of a controlled amount of clean water produces afree flowing grout. The grout exhibits exceptionalresistance to washing-out of the cement phase whenplaced in stationary or moving water.

Conbextra UW is a blend of cement, graded fineaggregate and chemical additives which impart controlledexpansion, water reduction and non wash-outcharacteristics. The aggregate grading minimisessegregation and bleeding whilst assisting the flowcharacteristics.

3URSHUWLHVThe following results were obtained at a water : powder ratioof 0.22.

Test method for Typical result

Compressive strength 5C 20C(BS 4550, Part 3: 1978) 1 day: 6 N/mm 25 N/mm3 days: 24 N/mm 38 N/mm7 days: 36 N/mm 44 N/mm28 days: 50 N/mm 53 N/mm

Setting time 5C 20C(BS 5075, Part 1: 1982) Initial: 13 hours 4.5 hoursFinal: 16.5 hours 5.5 hoursDensity of hardened grout: 2050 kg/m

Expansion characteristics: Controlled expansionoccurs in the unsetmaterial to ensure that thegrout, when cured, willcontinue to occupy itsoriginal volume within theconfines of the void inwhich it was placed.

$SSOLFDWLRQLQVWUXFWLRQV3UHSDUDWLRQThe substrate surface must be free from oil, grease or anyloosely adherent material. If the concrete surface isdefective or has laitance, it must be cut to a sound base.

Substrates which are permanently immersed should begrit-blasted or cleaned with a high pressure water jet.Non-immersed or intermittently immersed substrates canbe prepared using these techniques. Alternativelyscabbling or bush hammering may be appropriate.

)RUPZRUNThe formwork should be constructed to be leakproof asConbextra UW is a free flowing grout. This can beachieved by using foam rubber strip or Silicone Sealant33 beneath the constructed formwork and between joints.

0L[LQJDQGSODFLQJ0L[LQJFor best results a mechanically powered grout mixershould be used.

It is essential that machine mixing capacity and labouravailability is adequate to enable the grouting operation tobe carried out continuously. This may require the use of aholding tank with provision for gentle agitation to maintainfluidity.

Measure accurately 5.5 litres of water for each 25 kg baginto the mixer. Slowly add the Conbextra UW whilst mixingcontinuously. When all the powder is added mixcontinuously for 5 minutes ensuring a smooth evenconsistency is obtained. (Fluidity will increase withincreased mixing.)

3ODFLQJPlace the grout within 20 minutes of mixing to gain the fullbenefit of the expansion process. Continuous grout flow isessential.

The mixed grout should be poured or pumped through aflexible tube, having a minimum diameter of 50 mm, to thelowest point in the form.

Care must be taken at the start of the grouting operation torestrict the grout flow so that water is not entrapped.

The tube may be raised as necessary to reduce any backpressure. It should not be raised above the surface level

&RQEH[WUD8: constructive solutions

&,6I%

Page 2

&RQEH[WUD8:

&,6I%