08/27/2026
Glass and Concrete
Glass is amorphous silica, not crystalline silica. In certain particle sizes and conditions, it can trigger alkali-silica reaction (ASR). However, ASR can be mitigated, allowing glass to be used successfully in high-performance concrete mixes. The silicon dioxide in pozzolans reacts with free lime (calcium hydroxide) to form calcium silicate hydrate (CSH). When properly dosed, this reaction consumes enough free lime to help prevent ASR.
Clean glass is available in any color, but it can be expensive. A lower-cost option is to source waste glass and wash it yourself. Load a barrel mixer with glass and water, add one cup of muriatic acid, and let it rotate briefly. Before disposal, neutralize the water with one cup of ammonia.
Because glass particles are smooth, the concrete needs a stronger matrix to keep them in place during polishing. Very fine pozzolans, such as silica fume, help strengthen the matrix. Glass concrete around 6,000 PSI will polish acceptably, while mixes above 7,000 PSI can achieve an excellent polish.
Lower-strength concrete containing glass can develop an alligator-skin appearance when polished. Because the glass does not cut as easily as the surrounding matrix, valleys can form between the glass particles. When Trinic admixtures are used at the recommended dosages, producing high-performance concrete is essentially built into the mix.
Wet Cast Mix about 1 cf. - This is enough to produce 8 sq. ft. of wet cast concrete 1.5” thick.
Cementitious – 38 lbs.
• Portland Cement – 34 lbs.
• Trinic white silica Fume – 4 lbs.
Glass Sand- 50 lbs.
• A 30-70 mix will work.
Larger Glass (3/8” +) - 50 lbs.
• The sharper the glass particles the higher the water demand.
Water – 9.88 lbs.
• This will give you a water-to-cement ratio of 0.26, which is a very good starting point, your concrete will end up over 10,000 PSI. If you use less water great, if it looks like you need a more flowing mix, add more Trinic plasticizer rather than water.
Trinic Plasticizer – 0.19 pounds
• Start with 0.5% of total cementitious, more if needed.
Trinic TEC-10 – 0.76 lbs.
• 2% of the cementitious weight.
All Powder High-Performance Admixtures, Fiber, and Supplies: www.trinic.us
Trinic, LLC. [email protected] – 800-475-1975
