LARSEN CONCRETE & PLASTER BONDING AGENTS
Weld-Crete® Concrete Bonding Agent
Weld-Crete® bonds new concrete, stucco, tile setting beds and terrazzo to any structurally sound surface, interior or exterior. Use Weld-Crete’s® open time to your advantage in bonding to concrete shear walls when you need a time lapse between application of bonding agent, placement of reinforcement steel, placement of formwork and placement of concrete.
The original chemical concrete bonding agent, Weld-Crete® incorporates polyvinyl acetate homopolymer in a patented formulation. For exterior and interior use, Weld-Crete® will bond new concrete, Portland cement plaster and cementitious mixes to structurally sound concrete floors, walls, columns, beams, steps and ramps. Weld-Crete®can be "painted on" in a single application 1 hour to 10 days prior to concrete placement. Use Weld-Crete’s® open time to your advantage in bonding to concrete shear walls when you need a time lapse between application of bonding agent, placement of reinforcement steel, placement of formwork and placement of concrete.
Weld-Crete® is also used for: bonding setting beds for ceramic tile; bonding Portland cement plaster and stucco mixes; and to bond to surfaces such as brick, block, tile, marble, metal, glass block, soundly adhered paint (non-soluble in water, i.e. casein and calcimine paints), and silicone.
Property Test Method & Results
Tensile Bond Strength ASTM C-932 for Weld-Crete®,
average 485 psi. after 28 days.
Flexural Bond Strength ASTM C-78 (concrete beams laminated
with bonding agent). 603 psi.
Shear Bond Strength ASTM C-1042 (slant shear cylinder test).
740 psi. Avg. 14 days.
Temperature Range ASTM C-932 (Weld-Crete®)
specimens brought to 145º F, no bond failure.
Freeze-thaw Stability 5 cycles freeze (-10º F & thaw).
Toxicity Enclosed mice exposed to 30 cc volatilized
bonding agent for 1 hr. Non-toxic,
no ill effects after 7 days.
Fire Resistance ASTM E-119 (bonded assembly).
Passed 2 hr. Fire Test 1800º F and 1 hr. Hose Stream Test.
Flammability Lab. tests for fire resistance.
Non-flammable; meets MIL-B-19235C.
Acid Resistance 1” concrete slabs bonded to 1/2” gypsum plaster subjected
to seepage of strong detergents & synthetic urine for 10 hrs. a day.
No bond failure after 25 consecutive days.
Also unaffected by alkalinity of cement.
Life Expectancy Lab. tested & field proven. Non-deteriorating bond;
retains strength & flexibility