Removing bleed water by dragging a heavy rubber hose across the slab, or with a squeegee should be done only when water, not _______ is removed.

Removing bleed water by dragging a heavy rubber hose across the slab, or with a squeegee should be done only when water, not _______ is removed.

• A. Paste
• B. Cement
• C. Sludge
• D. Air

Answer: (A)

Bleed water on a freshly placed slab sits on top of a thin layer of cement paste that has risen with the water. The goal when removing that water with a heavy hose or a squeegee is to lift only the free water, not the cement paste that’s floating on the surface. If you drag across the surface when paste is present, you’ll pull that paste away, leaving a weak, chalky laitance or a rough finish and potentially exposing the underlying, less-set concrete. Keeping the surface paste-restricted preserves the surface integrity and allows proper finishing afterward. The other options don’t fit because air isn’t a material to be removed in this context, and sludge or cement already form part of the paste mix rather than clean water that should be wiped away. The emphasis is on not removing the cement paste with the bleed-water removal process.

Bleed water on a freshly placed slab sits on top of a thin layer of cement paste that has risen with the water. The goal when removing that water with a heavy hose or a squeegee is to lift only the free water, not the cement paste that’s floating on the surface. If you drag across the surface when paste is present, you’ll pull that paste away, leaving a weak, chalky laitance or a rough finish and potentially exposing the underlying, less-set concrete. Keeping the surface paste-restricted preserves the surface integrity and allows proper finishing afterward.

The other options don’t fit because air isn’t a material to be removed in this context, and sludge or cement already form part of the paste mix rather than clean water that should be wiped away. The emphasis is on not removing the cement paste with the bleed-water removal process.