Underwater Grouts

Typical uses include the production of non-dispersible underwater concrete and reduction of the accumulation of bleed water in mass concrete placed in deep forms. Consequently, AWAs are useful in mass concrete work because they prevent the formation of laitance on the surface of the concrete and thereby reduce the excessive cleaning between successive lifts. The admixtures also reduce the voids formed under horizontal reinforcing bars. Therefore, bond to steel increases and potential corrosion problems are reduced. The admixtures are also used in conjunction with WRAs in oil-well cementing grouts to reduce pipeline friction and rapid water loss and grouting of pre- and post-tensioned concrete ducts [47]. New valves and control devices under development in Europe and Japan used in conjunction with AWA will likely advance the field on underwater concrete. 

Other applications include the construction of floor slabs where manipulation of the level of the admixture in the concrete will result in the production of bleed water should it be required to enhance finishing. The use of VEAs in grouting and underwater concrete applications is discussed below. 

Chem. Descrip. Aliphatic amine Uses Curing agent for grouts, sealants, underwater coatings Properties Gardner 9 max. color dens. 7.8 Ib/gal vise. 700-900 cP amine no. 230-250 EEW 152 gel time 48 min (100 g)... 

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