Lightweight compositions and articles containing such
A lightweight cementitious composition containing from 22 to 90 volume percent of a cement composition and from 10 to 78 volume percent of particles having an average particle diameter of from 0.2 mm to 8 mm, a bulk density of from 0.03 g/cc to 0.64 g/cc, an aspect ratio of from 1 to 3, where after the lightweight cementitious composition is set it has a compressive strength of at least 1700 psi as tested according to ASTM C39. The cementitious composition can be used to make concrete masonry units, construction panels, road beds and other articles and can be included as a layer on wall panels and floor panels and can be used in insulated concrete forms. Aspects of the lightweight cementitious composition can be used to make lightweight structural units.
1. A lightweight concrete composition comprising
from 22 to 90 volume percent of a cementitious mixture,
water, and
from 10 to 78 volume percent of particles having
an average particle diameter of from 0.2 mm to 3 mm,
a bulk density of from 0.02 g/cc to 0.48 g/cc,
a substantially continuous outer layer, and
an aspect ratio of from 1 to 3,
wherein the concrete composition is substantially free of air entraining agents;
wherein the concrete composition has a density of from 90 to about 130 lb./ft 3 ; and
wherein after the lightweight concrete composition when set has a 7-day compressive strength of at least 1700 psi as tested according to ASTM C39.
2. The lightweight concrete composition according to claim 1 , wherein the particles comprise expanded polymer particles having an inner cell wall thickness of at least at least 0.15 μm.
3. The lightweight concrete composition according to claim 1 , wherein the particles comprise expanded polymer particles comprising one or more polymers selected from the group consisting of homopolymers of vinyl aromatic monomers; copolymers of at least one vinyl aromatic monomer with one or more of divinylbenzene, conjugated dienes, alkyl methacrylates, alkyl acrylates, acrylonitrile, and/or maleic anhydride; polyolefins; polycarbonates; polyesters; polyamides; natural rubbers; synthetic rubbers; and combinations thereof.
4. The lightweight concrete composition according to claim 1 , wherein the particles comprise expanded polymer particles prepared by expanding a polymer bead having an unexpanded average resin particle size of from about 0.2 mm to about 1 mm.
5. The lightweight concrete composition according to claim 1 as a dispersion wherein the cementitious mixture and water comprises a continuous phase and the particles comprise a dispersed phase of discrete particles in the continuous phase.
6. The lightweight concrete composition according to claim 5 containing no wetting agents or dispersing agents to stabilize the dispersion.
7. The lightweight concrete composition according to claim 1 , wherein at least some of the particles are arranged in a cubic or hexagonal lattice.
8. The lightweight concrete composition according to claim 1 , wherein the cementitious mixture comprises a hydraulic cement composition.
9. The lightweight concrete composition according to claim 8 , wherein the hydraulic cement comprises one or more materials selected from the group consisting of Portland cements, pozzolana cements, gypsum cements, gypsum compositions, aluminous cements, magnesia cements, silica cements, and slag cements.
10. The lightweight concrete composition according to claim 1 , wherein the cementitious mixture comprises sand, aggregate, plasticizers and/or fibers.
11. The lightweight concrete composition according to claim 10 , wherein the fibers are selected from the group consisting of glass fibers, silicon carbide, aramid fibers, polyester, carbon fibers, composite fibers, fiberglass, combinations thereof, fabric containing said fibers, and fabric containing combinations of said fibers.
12. The lightweight concrete composition according to claim 10 , wherein the aggregate is selected from the group consisting of stone, gravel, expanded slate, pumice, perlite, vermiculite, scoria, diatomite, expanded shale, expanded clay, expanded slag, pelletized aggregate, tuff, macrolite, slate, and combinations thereof.
13. The lightweight concrete composition according to claim 1 , wherein a standard 2½ inch drywall screw, screwed into the formed and set lightweight concrete composition to a depth of 1½ inches, is not removed by applying 500 pounds of force perpendicular to the surface screwed into for one minute.
14. The lightweight concrete composition according to claim 1 molded and set in the form of a construction article.
15. The lightweight concrete composition according to claim 1 set in the form of a concrete masonry unit.
16. The lightweight concrete composition according to claim 1 set in the form of a construction panel.
17. A concrete composition comprising:
from 22 to 90 volume percent of a cementitious mixture containing sand and from 5 to 40 volume percent of a hydraulic cement composition;
one or more aggregates selected from the group consisting of stone, gravel, and combinations thereof;
water; and
from 10 to 78 volume percent of expanded polymer particles formed by expanding polymer beads having an unexpanded average resin particle size of from about 0.2 mm to about 1 mm to an average expanded polymer particle diameter of from 1 mm to 3 mm, a bulk density of from 0.02 g/cc to 0.48 g/cc, a continuous outer surface, and an aspect ratio of from 1 to 3;
wherein the concrete composition is substantially free of air entraining agents;
wherein after the concrete composition is set and hardened has a density of from 90 to about 130 lb./ft 3 and has a 7-day compressive strength of at least 1800 psi as tested according to ASTM C39.
18. The concrete composition according to claim 17 , wherein the expanded polymer particles comprise one or more polymers selected from the group consisting of homopolymers of vinyl aromatic monomers; copolymers of at least one vinyl aromatic monomer with one or more of divinylbenzene, conjugated dienes, alkyl methacrylates, alkyl acrylates, acrylonitrile, and/or maleic anhydride; polyolefins; polycarbonates; polyesters; polyamides; natural rubbers; synthetic rubbers; and combinations thereof.
19. The concrete composition according to claim 18 , wherein the expanded polymer particles comprise polystyrene.
20. The concrete composition according to claim 17 , wherein the expanded polymer particles having an inner cell wall thickness of at least at least 0.15 μm.
21. The concrete composition according to claim 17 , wherein at least some of the expanded polymer particles are arranged in a cubic or hexagonal lattice.
22. The concrete composition according to claim 17 , wherein the hydraulic cement composition comprises one or more materials selected from the group consisting of Portland cements, pozzolana cements, gypsum cements, aluminous cements, magnesia cements, silica cements, and slag cements.
23. The concrete composition according to claim 17 comprising fibers.
24. The concrete composition according to claim 23 , wherein the fibers are selected from the group consisting of glass fibers, silicon carbide, aramid fibers, polyester, carbon fibers, composite fibers, fiberglass, combinations thereof, fabric containing said fibers, and fabric containing combinations of said fibers.
25. The concrete composition according to claim 17 comprising aggregate selected from the group consisting of glass, expanded slate, pumice, perlite, vermiculite, scoria, diatomite, expanded shale, expanded clay, expanded slag, pelletized aggregate, tuff, macrolite, slate, and combinations thereof.
26. A concrete composition comprising:
from 22 to 90 volume percent of a cementitious mixture containing:
from 1 to 60 volume percent of sand;
from 5 to 40 volume percent of a hydraulic cement composition;
from 0.5 to 60 volume percent of one or more aggregates selected from the group consisting of stone, gravel, and combinations thereof; and
optionally, one or more adjuvants selected from the group consisting of plasticizers, fibers, colorants, water reducers, and superplasticizers;
water; and
from 10 to 78 volume percent of expanded polystyrene particles formed by expanding polystyrene beads having an unexpanded average resin particle size of from about 0.33 mm to about 1 mm to an average expanded polystyrene particle diameter of from 1 mm to 3 mm, a bulk density of from 0.03 g/cc to 0.48 g/cc, a continuous outer surface, and an aspect ratio of from 1 to 3;
wherein the concrete composition is substantially free of air entraining agents;
wherein after the concrete composition is set and hardened has a density of from 90 to about 130 lb./ft 3 and has a 7-day compressive strength of at least 1800 psi as tested according to ASTM C39.
27. The concrete composition according to claim 26 , wherein the hydraulic cement composition comprises one or more materials selected from the group consisting of Portland cements, pozzolana cements, gypsum cements, aluminous cements, magnesia cements, silica cements, and slag cements.
28. The concrete composition according to claim 26 , wherein the polymer particles have an inner cell wall thickness of at least at least 0.15 μm.
29. The concrete composition according to claim 26 , wherein the fibers are selected from the group consisting of glass fibers, silicon carbide, aramid fibers, polyester, carbon fibers, composite fibers, fiberglass, combinations thereof, fabric containing said fibers, and fabric containing combinations of said fibers.