LOW-DENSITY HIGH-STRENGTH CONCRETE AND RELATED METHODS

1 . Unmixed components of a LWC mix, comprising:

one or more cementitious materials; and

one or more LWA;

said one or more LWA comprising glass microspheres; and

said glass microspheres having a specific gravity less than about 0.36.

2 . The unmixed components of a LWC mix of claim 1 ,

said glass microspheres having a specific gravity of about 0.15.

3 . The unmixed components of a LWC mix of claim 1 ,

said glass microspheres having a crush strength below about 2000 psi.

4 . The unmixed components of a LWC mix of claim 1 ,

said glass microspheres having a specific gravity of about 0.35.

5 . The unmixed components of a LWC mix of claim 1 ,

said glass microspheres having a crush strength of about 3000 psi.

6 . The unmixed components of a LWC mix of claim 1 ,

said glass microspheres having a median size distribution of greater than about 45 microns.

7 . The unmixed components of a LWC mix of claim 1 ,

further comprising one or more ordinary aggregates;

wherein each of said cementitious materials, one or more LWA, and one or more ordinary aggregates has a weight; and

wherein a ratio of the weight of LWA to a sum of the said weights is less than about 50%.

8 . The unmixed components of a LWC mix of claim 7 ,

wherein the said ratio is about 15%.

9 . The unmixed components of a LWC mix of claim 7 ,

wherein the said ratio is about 42%.

10 . The unmixed components of a LWC mix of claim 1 ,

said cementitious materials comprising a Portland cement, a class F fly ash, and silica fume;

said Portland cement, fly ash, silica fume and glass microspheres prepared in about the following respective proportions by weight 4.92:1.28:0.216:1.

11 . The unmixed components of a LWC mix of claim 10 ,

further comprising a fiber reinforcing material;

said Portland cement, fly ash, silica fume, glass microspheres and a fiber reinforcing material prepared in about the following respective proportions by weight 4.92:1.28:0.216:1:0.0541.

12 . The unmixed components of a LWC mix of claim 1 ,

further comprising sand;

said cementitious materials comprising a Portland cement, a class F fly ash, and silica fume;

said Portland cement, fly ash, silica fume, glass microspheres and sand prepared in about the following respective proportions by weight 2.44:0.635:0.108:1:1.33.

13 . The unmixed components of a LWC mix of claim 1 ,

said glass microspheres comprising microspheres having a specific gravity of about 0.15 and microspheres having a specific gravity of about 0.35.

14 . The unmixed components of a LWC mix of claim 1 ,

said one or more cementitious materials comprising a Portland cement;

said glass microspheres and one or more cementitious materials prepared in about the following respective proportions by weight: 1:2.8-8.9.

15 . The unmixed components of a LWC mix of claim 14 ,

said one or more cementitious materials composed essentially of said Portland cement;

said glass microspheres and said Portland cement prepared in about the following respective proportions by weight: 1:5.5-6.0.

16 . The unmixed components of a LWC mix of claim 14 ,

said glass microspheres comprising microspheres having a specific gravity of about 0.15.

17 . The unmixed components of a LWC mix of claim 1 ,

further comprising one or more ordinary aggregates;

said cementitious materials comprising a Portland cement, and a class F fly ash;

said Portland cement, fly ash, glass microspheres and one or more ordinary aggregates prepared in about the following respective proportions by weight: 3-7:0.75-1.75:1:6.5-22.

18 . The unmixed components of a LWC mix of claim 17 ,

said one or more ordinary aggregates comprising a coarse aggregate and sand;

said Portland cement, fly ash, glass microspheres, coarse aggregate and sand prepared in about the following respective proportions by weight: 6.3:1.6:1:14.8:5.9.

19 . The unmixed components of a LWC mix of claim 17 ,

said one or more ordinary aggregates comprising sand;

said Portland cement, fly ash, glass microspheres and sand prepared in about the following respective proportions by weight: 3.3:0.8:1:7.4.

20 . Unmixed components of a LWC mix, comprising:

dry components;

said dry components comprising one or more cementitious materials and one or more LWA;

wherein said each of said dry components has a weight;

said one or more LWA comprising glass microspheres;

said glass microspheres having a specific gravity less than about 0.36; and

wherein a ratio of the weight of LWA to a sum of the said weights is less than about 50%.

21 . The unmixed components of the LWC mix of claim 20 :

said dry components further comprising one or more ordinary aggregates having a weight;

wherein the said ratio is less than about 45%.

22 . The unmixed components of the LWC mix of claim 20 :

wherein the said ratio is less than about 30%.

23 . The unmixed components of the LWC mix of claim 20 :

wherein the said ratio is less than about 15%.

24 . Unmixed components of a LWC mix, comprising:

one or more cementitious materials; and

one or more LWA;

said one or more LWA comprising closed-cell and non-absorptive particles; and

said particles having a specific gravity less than about 0.36.

25 . The unmixed components of a LWC mix of claim 24 ,

said particles having a specific gravity of about 0.15 and a crush strength below about 350 psi.

26 . The unmixed components of a LWC mix of claim 24 ,

said particles having a specific gravity of about 0.35 and a crush strength of about 3000 psi.

27 . The unmixed components of a LWC mix of claim 24 ,

said particles comprising glass microspheres having a median size distribution of greater than about 45 microns.

28 . The unmixed components of a LWC mix of claim 24 ,

further comprising one or more ordinary aggregates.

29 . The unmixed components of a LWC mix of claim 28 ,

said one or more ordinary aggregates comprising sand.

30 . The unmixed components of a LWC mix of claim 24 ,

said one or more cementitious materials comprising a Portland cement;

said particles and one or more cementitious materials prepared in about the following respective proportions by weight: 1:2.8-8.9.

31 . The unmixed components of a LWC mix of claim 30 ,

said one or more cementitious materials composed essentially of said Portland cement;

said particles and said Portland cement prepared in about the following respective proportions by weight: 1:5.5-6.0.

32 . The unmixed components of a LWC mix of claim 31 ,

said particles comprising glass microspheres having a specific gravity of about 0.15.

33 . The unmixed components of a LWC mix of claim 24 ,

further comprising one or more ordinary aggregates;

said one or more cementitious materials comprising a Portland cement, and a class F fly ash;

said Portland cement, fly ash, particles and one or more ordinary aggregates prepared in about the following respective proportions by weight: 3-7:0.75-1.75:1:6.5-22.

34 . A LWC composition, comprising:

one or more cementitious materials;

water; and

one or more aggregates;

said aggregates comprising LWA and a coarse aggregate;

said one or more LWA comprising closed-cell and non-absorptive particles;

wherein each of said one or more cementitious materials, water, and one or more aggregates has a volume; and

wherein a ratio of the volume of the LWA to a sum of the said volumes is at least about 15%.

35 . The LWC composition of claim 34 ,

said LWA having a specific gravity less than about 0.36.

36 . The LWC composition of claim 34 ,

wherein the ratio is about 17%.

37 . The LWC composition of claim 36 ,

said one or more aggregates further comprising sand.

38 . The LWC composition of claim 34 ,

wherein the ratio is between about 30% and 38%.

39 . The LWC composition of claim 38 ,

wherein sand is excluded from said composition.

40 . A LWC composition, comprising:

one or more cementitious materials;

water; and

one or more aggregates;

said aggregates comprising glass microspheres;

wherein each of said one or more cementitious materials, water, and one or more aggregates has a volume; and

wherein a ratio of the volume of the glass microspheres to a sum of the said volumes is at least about 39%.

41 . The LWC composition of claim 40 ,

said composition having a plastic density in the range of about 50 to about 58 lb./cu. ft.

42 . The LWC composition of claim 40 ,

wherein the ratio is about 50%.

43 . The LWC composition of claim 42 ,

said glass microspheres having a specific gravity less than about 0.36.

43 . The LWC composition of claim 40 ,

said glass microspheres having a median size distribution of greater than about 45 microns.

45 . The LWC composition of claim 40 ,

said one or more aggregates further comprising sand; and

wherein the ratio is about 40%

46 . The LWC composition of claim 45 ,

said composition having a plastic density in the range of about 65 to about 75 lb./cu. ft.

47 . The LWC composition of claim 40 ,

said cementitious materials comprising a Portland cement, a class F fly ash, and silica fume;

said Portland cement, fly ash, silica fume, glass microspheres and water in about the following respective proportions by weight 4.92:1.28:0.216:1:3.63.

48 . The LWC composition of claim 47 ,

further comprising a fiber reinforcing material;

said Portland cement, fly ash, silica fume, glass microspheres, water and a fiber reinforcing material prepared in about the following respective proportions by weight 4.92:1.28:0.216:1:3.63:0.0541.

49 . The LWC composition of claim 40 ,

said one or more aggregates further comprising sand;

said cementitious materials comprising a Portland cement, a class F fly ash, and silica fume;

said Portland cement, fly ash, silica fume, glass microspheres, water and sand prepared in about the following respective proportions by weight 2.44:0.635:0.108:1:1.84:1.33.

50 . The LWC composition of claim 40 ,

wherein the composition is self-compacting.

51 . The LWC composition of claim 40 ,

said composition having a plastic density;

said plastic density being homogenous.

52 . The LWC composition of claim 51 ,

said plastic density within said composition varying by less than about 15%.

53 . The LWC composition of claim 51 ,

said plastic density within said composition varying by less than about 1%.

54 . The LWC composition of claim 51 ,

said cementitious materials comprising a Portland cement, a class F fly ash, and silica fume components; and

said mix comprising in total percent by weight:

a) Portland cement in the amount of 30-46;

b) fly ash in the amount of 7-14;

c) silica fume in the amount of 1.0-2.5;

d) glass microspheres in the amount of 3-21.5; and

e) water in the amount of 21-38.

55 . The LWC composition of claim 54 ,

said glass microspheres having a specific gravity of about 0.15; and

said components comprising in total percent by weight:

a) Portland cement in the amount of 32-44;

b) fly ash in the amount of 8-12;

c) silica fume in the amount of 1.4-2.0; and

d) glass microspheres in the amount of 5-10; and

e) water in the amount of 24-35.

56 . The LWC composition of claim 54 ,

further comprising sand;

said glass microspheres having a specific gravity of about 0.35; and

said components comprising in total percent by weight:

a) Portland cement in the amount of 30-35;

b) fly ash in the amount of 7-9;

c) silica fume in the amount of 1.2-1.6; and

d) glass microspheres in the amount of 12-15;

e) sand in the amount of 10-25; and

f) water in the amount of 22-27.

57 . A LWC composition, comprising:

one or more cementitious materials;

water; and

one or more aggregates;

said aggregates comprising closed-cell and non-absorptive particles; said composition having a plastic density;

said plastic density being substantially homogenous.

58 . The LWC composition of claim 57 ,

said plastic density varying by less than about 15%.

59 . The LWC composition of claim 57 ,

wherein the composition is self-compacting.

60 . A LWC composition, comprising:

one or more cementitious materials;

water; and

one or more aggregates;

said one or more aggregates comprising closed-cell and non-absorptive particles;

said one or more cementitious materials and water prepared in about the following respective proportions by weight: 1:0.15-0.35.

61 . The LWC composition of claim 60 ,

said one or more cementitious materials composed essentially of said Portland cement;

said Portland cement and water prepared in about the following respective proportions by weight: 1:0.22.

62 . The LWC composition of claim 60 ,

said one or more cementitious materials comprising a Portland cement;

said one or more cementitious materials, water and particles prepared in about the following respective proportions by weight: 1:0.22:0.10-0.35.

63 . The LWC composition of claim 60 ,

said one or more cementitious materials, water and particles prepared in about the following respective proportions by weight: 1:0.22:0.15-020; and

said particles having a specific gravity of about 0.15.

64 . The steps of mixing a LWC composition, comprising the steps of:

adding one or more cementitious materials to a concrete mixer;

adding water to the mixer; and

adding one or more aggregates to the mixer;

said aggregates comprising glass microspheres;

wherein each of said one or more cementitious materials, water, and one or more aggregates has a volume; and

wherein a ratio of the volume of the glass microspheres to a sum of the said volumes is at least about 39%.

65 . The steps of mixing the LWC composition of claim 64 ,

said mix having a plastic density in the range of about 50 to about 58 lb./cu. ft.

66 . The steps of mixing the LWC composition of claim 64 ,

wherein the ratio is about 50%.

67 . The steps of mixing the LWC composition of claim 64 ,

said one or more aggregates further comprising sand; and

wherein the ratio is about 40%

68 . The steps of mixing the LWC composition of claim 64 ,

said concrete mixer being the rotating drum of a concrete mixing truck; and

further comprising the step of operating the rotating drum to mix the LWC composition.

69 . The steps of mixing the LWC composition of claim 64 ,

said concrete mixer being stationary; and

further comprising the step of operating the concrete mixer to mix the LWC composition.

70 . The steps of mixing a LWC composition, comprising the steps of:

adding dry components to a concrete mixer;

said dry components comprising one or more cementitious materials and one or more LWA; and

said LWA comprising glass microspheres;

wherein said each of said dry components has a weight; and

wherein a ratio of the weight of LWA to a sum of the said weights of said dry components is less than about 50%.

71 . The steps of mixing a LWC composition of claim 70 :

said dry components further comprising one or more ordinary aggregates having a weight;

wherein the said ratio is less than about 25%.

72 . The steps of mixing a LWC composition of claim 70 :

wherein the said ratio is less than about 30%.

73 . The steps of mixing a LWC composition of claim 70 :

wherein the said ratio is less than about 15%.

74 . The steps of mixing a LWC composition of claim 70 :

said concrete mixer being the rotating drum of a concrete mixing truck.

75 . The steps of mixing a LWC composition of claim 74 :

further comprising the step of operating the rotating drum to mix the LWC composition.

76 . The steps of mixing a LWC composition of claim 70 :

said concrete mixer being stationary; and

further comprising the step of operating the concrete mixer to mix the LWC composition.

77 . The steps of mixing a LWC composition of claim 70 :

said one or more cementitious materials comprising a Portland cement, a class F fly ash, and silica fume components; and

adding water to the concrete mixer;

wherein said water has a weight; and

said adding steps further comprising adding in total percent by weight:

a) Portland cement in the amount of 30-46;

b) fly ash in the amount of 7-14;

c) silica fume in the amount of 1.0-2.5;

d) glass microspheres in the amount of 3-21.5; and

e) water in the amount of 21-38.

78 . The steps of mixing a LWC composition of claim 77 :

said glass microspheres having a specific gravity of about 0.15; and

said adding steps comprising adding in total percent by weight:

a) Portland cement in the amount of 32-44;

b) fly ash in the amount of 8-12;

c) silica fume in the amount of 1.4-2.0; and

d) glass microspheres in the amount of 5-10; and

e) water in the amount of 24-35.

79 . The steps of mixing a LWC composition of claim 77 ,

further comprising sand;

said glass microspheres having a specific gravity of about 0.35; and

said adding steps further comprising adding in total percent by weight:

a) Portland cement in the amount of 30-35;

b) fly ash in the amount of 7-9;

c) silica fume in the amount of 1.2-1.6; and

d) glass microspheres in the amount of 12-15;

e) sand in the amount of 10-25; and

f) water in the amount of 22-27.

80 . The steps of mixing a LWC composition, comprising the steps of:

adding dry components to a concrete mixer;

said dry components comprising one or more cementitious materials, one or more ordinary aggregates, and one or more LWA; and

wherein said LWA is closed-cell and non-absorptive;

wherein said each of said dry components has a weight; and

wherein a ratio of the weight of LWA to a sum of the said weights of said dry components is between about 2% and 20%.

81 . The steps of mixing a LWC composition of claim 80 :

said one or more ordinary aggregates comprising sand; and

wherein the said ratio is between about 6-15%.

82 . The steps of mixing a LWC composition of claim 80 :

said composition having a plastic density of between about 70 and 130 lb./cu. ft.

83 . The steps of mixing a LWC composition of claim 80 :

said composition having a plastic density of between about 65 and 70 lb./cu. ft.

84 . The steps of mixing a LWC composition of claim 80 :

said one or more ordinary aggregates comprising sand; and

wherein the said ratio is about 18%.

85 . The steps of mixing a LWC composition of claim 80 :

said one or more ordinary aggregates composed essentially of sand; and

wherein the said ratio is about 2%.

86 . The steps of mixing a LWC composition of claim 80 :

said one or more ordinary aggregates comprising a coarse aggregate; and

wherein the said ratio is between about 2-12%.

87 . The steps of mixing a LWC composition of claim 80 :

said composition having a plastic density of between about 75 and 140 lb./cu. ft.

88 . The steps of mixing a LWC composition of claim 80 :

said one or more ordinary aggregates comprising a coarse aggregate; and

wherein the said ratio is about between about 2.5% and 4%.

89 . The steps of mixing a LWC composition of claim 80 :

said one or more ordinary aggregates comprising sand and a coarse aggregate; and

wherein the ratio of the weights of the sand to the coarse aggregate is about 1:0.35-0.45.

90 . The steps of mixing a LWC composition of claim 80 :

said one or more cementitious materials comprising a Portland cement, a class F fly ash, and silica fume components;

said one or more ordinary aggregates further comprising sand; and

adding water to the concrete mixer;

wherein said water has a weight; and

said adding steps further comprising adding in total percent by weight:

a) Portland cement in the amount of 18-34;

b) fly ash in the amount of 4-10;

c) silica fume in the amount of 0.5-2.0;

d) LWA in the amount of 1.5-15;

e) sand in the amount of 16-65; and

f) water in the amount of 8-26.

91 . The steps of mixing a LWC composition of claim 90 :

said adding steps further comprising adding in total percent by weight:

a) Portland cement in the amount of about 32-33;

b) fly ash in the amount of 8.5-8.6;

c) silica fume in the amount of 1.45;

d) LWA in the amount of 13-14;

e) sand in the amount of 17-18; and

f) water in the amount of 24-25.

92 . The steps of mixing a LWC composition of claim 80 :

said one or more cementitious materials comprising a Portland cement, a class F fly ash, and silica fume components;

said one or more ordinary aggregates comprising a coarse aggregate; and

adding water to the concrete mixer;

wherein said water has a weight; and

said adding steps further comprising adding in total percent by weight:

a) Portland cement in the amount of 17-29;

b) fly ash in the amount of 4-8;

c) silica fume in the amount of 0.0-1.2;

d) LWA in the amount of 2.0-11;

e) one or more ordinary aggregates in the amount of 35-65; and

f) water in the amount of 6-16.

93 . The steps of mixing a LWC composition of claim 92 :

said one or more ordinary aggregates further comprising sand; and

said adding steps further comprising adding in total percent by weight:

a) Portland cement in the amount of about 17-20;

b) fly ash in the amount of 4.7-5.2;

c) silica fume in the amount of 0.0-0.9;

d) LWA in the amount of 2.5-3.5;

e) coarse aggregate in the amount of 43-47;

f) sand in the amount of 17-19; and

g) water in the amount of 7-9.

94 . The steps of mixing a LWC composition, comprising the steps of:

adding dry components to a concrete mixer;

said dry components comprising one or more cementitious materials, and one or more LWA; and

wherein said LWA is closed-cell and non-absorptive;

adding water to the concrete mixer;

wherein said water has a weight; and

said adding steps further comprising adding said one or more cementitious materials and water in about the following respective proportions by weight: 1:0.15-0.35.

95 . The steps of mixing a LWC composition of claim 94 ,

said one or more cementitious materials composed essentially of a Portland cement; and

said adding steps further comprising adding said Portland cement and water in about the following respective proportions by weight: 1:0.22.

96 . The steps of mixing a LWC composition of claim 94 ,

said LWA having a specific gravity of below about 0.36.

96 . The steps of mixing a LWC composition of claim 94 ,

said dry components further comprising sand.

97 . The steps of mixing a LWC composition of claim 94 ,

said one or more cementitious materials comprising a Portland cement; and

said adding steps further comprising adding said Portland cement, water and the LWA in about the following respective proportions by weight: 1:0.20-0.35:0.10-0.35.

98 . The steps of mixing a LWC composition of claim 94 ,

further comprising the step of vibrating said composition in a form.

99 . The steps of mixing a LWC composition of claim 94 ,

further comprising the step of compressing said composition in a form.

100 . The steps of providing the unmixed components of a LWC composition, comprising the steps of:

providing one or more cementitious materials; and

providing one or more LWA;

said one or more LWA comprising glass microspheres; and

said glass microspheres having a specific gravity less than about 0.36.

101 . The steps of providing the unmixed components of a LWC composition of claim 100 ,

said glass microspheres having a specific gravity of about 0.15.

102 . The steps of providing the unmixed components of a LWC composition of claim 100 ,

said glass microspheres having a specific gravity of about 0.35.

103 . The steps of providing the unmixed components of a LWC composition of claim 100 ,

said glass microspheres having a median size distribution of greater than about 45 microns.

104 . The steps of providing the unmixed components of a LWC composition of claim 100 ,

further comprising providing one or more ordinary aggregates;

further comprising providing one or more reinforcing materials;

wherein each of said cementitious materials, one or more LWA, and one or more ordinary aggregates, has a weight; and

further comprising providing the components such that a ratio of the weight of LWA to a sum of the said weights is less than about 50%.

105 . The steps of providing the unmixed components of a LWC composition of claim 100 ,

said step of providing one or more cementitious materials comprising providing a Portland cement, a class F fly ash, and silica fume;

said providing steps comprising providing said Portland cement, fly ash, silica fume and glass microspheres in about the following respective proportions by weight 4.92:1.28:0.216:1.

106 . The steps of providing the unmixed components of a LWC composition of claim 105 ,

further comprising providing water;

said providing steps comprising providing said Portland cement, fly ash, silica fume, glass microspheres and water in about the following respective proportions by weight 4.92:1.28:0.216:1:3.63.

107 . The steps of providing the unmixed components of a LWC composition of claim 105 ,

further comprising providing fiber reinforcing material;

said providing steps comprising providing said Portland cement, fly ash, silica fume, glass microspheres and fiber reinforcing material in about the following respective proportions by weight 4.92:1.28:0.216:1:0.0541.

108 . The steps of providing the unmixed components of a LWC composition of claim 100 ,

further comprising providing sand;

said step of providing one or more cementitious materials comprising providing a Portland cement, a class F fly ash, and silica fume;

said providing steps comprising providing said Portland cement, fly ash, silica fume, glass microspheres and sand in about the following respective proportions by weight 2.44:0.635:0.108:1:1.33.

109 . The steps of providing the unmixed components of a LWC composition of claim 108 ,

further comprising providing water;

said providing steps comprising said Portland cement, fly ash, silica fume, glass microspheres, water and sand in about the following respective proportions by weight 2.44:0.635:0.108:1:1.84:1.33.

110 . The steps of providing the unmixed components of a LWC composition of claim 100 ,

the steps of providing said one or more cementitious materials and said one or more LWA comprising depositing said one or more cementitious materials and said one or more LWA into a rotatable mixing drum.

111 . The steps of providing the unmixed components of a LWC composition of claim 100 ,

said rotatable mixing drum being mounted on a concrete mixing truck.

112 . The steps of providing the unmixed components of a LWC composition, comprising the steps of:

providing one or more cementitious materials; and

providing one or more LWA;

said one or more LWA being closed-cell and non-absorptive; and

said LWA having a specific gravity less than about 0.36.

112 . The steps of providing the unmixed components of a LWC composition of claim 111 ,

said LWA having a specific gravity of about 0.35.

113 . The steps of providing the unmixed components of a LWC composition of claim 111 ,

said LWA having a median size distribution of greater than about 45 microns.

114 . The steps of providing the unmixed components of a LWC composition of claim 111 ,

further comprising providing an ordinary aggregate.

115 . Concrete blocks formed of a LWC, comprising one or more cementitious materials; and

one or more LWA;

wherein said LWC has a 14-day compressive strength of over about 850.

116 . The LWC of claim 115 ,

said LWC formed from a LWC composition comprising said one or more cementitious materials, water and LWA and in which said one or more cementitious materials and water were present in about the following respective proportions by weight: 1:0.15-0.35.

117 . The LWC of claim 115 ,

said LWC formed from a LWC composition comprising said one or more cementitious materials, water and LWA and in which said materials were present in about the following respective proportions by weight: 1:0.22:0.15-0.35.

118 . The LWC of claim 115 ,

said one or more cementitious materials and LWA present in about the following respective proportions by weight: 1:0.10-0.35.

119 . The LWC composition of claim 115 ,

said one or more LWA being closed-cell and non-absorptive; and

wherein said LWC has a 14-day compressive strength of over about 1000.

120 . A LWC, comprising

one or more cementitious materials; and

one or more LWA;

wherein said LWC has a 7-day compressive strength in psi and an oven-dried density in lb./cu. ft; and

wherein a ratio of said 7-day compressive strength and said density is above about 30.

121 . The LWC of claim 120 ,

wherein said ratio is above about 40.

122 . The LWC of claim 120 ,

wherein said LWC has a 28-day compressive strength in psi; and

wherein a ratio of said 28-day compressive strength and said density is above about 45.

123 . The LWC of claim 122 ,

said one or more LWA comprising glass microspheres; and

said glass microspheres having a specific gravity of about 0.15.

124 . The LWC of claim 122 ,

wherein said ratio of said 28-day compressive strength and said density is above about 70.

125 . The LWC of claim 122 ,

said one or more LWA comprising glass microspheres; and

said glass microspheres having a specific gravity of about 0.35.

126 . The LWC of claim 121 ,

further comprising one or more coarse aggregate.

127 . The LWC of claim 120 ,

wherein said 7-day compressive strength is at least about 1200 psi.

128 . The LWC of claim 127 ,

wherein said LWC has a 28-day compressive strength of at least about 1750 psi.

129 . The LWC of claim 128 ,

wherein said 28-day compressive strength is at least about 2500 psi.

130 . The LWC of claim 128 ,

wherein said 28-day compressive strength is at least about 3300 psi.

131 . The LWC of claim 120 ,

wherein said density is less than about 42.

132 . The LWC of claim 131 ,

wherein said LWC has a 28-day compressive strength of at least about 2500 psi.

133 . The LWC of claim 131 ,

said LWA being closed-cell and non-absorptive.

134 . The LWC of claim 120 ,

further comprising one or more reinforcing materials;

wherein each of said cementitious materials, one or more LWA, and one or more reinforcing materials has a weight; and

wherein a ratio of the weight of LWA to a sum of the said weights is less than about 35%.

135 . The LWC of claim 134 ,

wherein the said weight ratio is between about 28% and about 33%.

136 . The LWC of claim 134 ,

wherein the said weight ratio is between about 12% and about 16%.

137 . The LWC of claim 120 ,

further comprising one or more ordinary aggregates;

further comprising one or more reinforcing materials;

wherein each of said cementitious materials, one or more LWA, one or more ordinary aggregates, and one or more reinforcing materials has a weight; and

wherein a ratio of the weight of LWA to a sum of the said weights is less than about 50%.

138 . The LWC of claim 137 ,

wherein the said weight ratio is less than 45%

139 . The LWC of claim 137 ,

wherein the said weight ratio is about 42%

140 . The LWC of claim 120 ,

wherein said LWC has an R-value of at least about 0.4/inch.

141 . The LWC of claim 140 ,

wherein said R-value is at least about 0.8/inch; and

wherein said 7-day compressive strength is at least about 1200 psi.

142 . The LWC of claim 141 ,

wherein said 7-day compressive strength is at least about 1500 psi.

143 . The LWC of claim 140 ,

wherein said R-value is at least about 0.7/inch; and

wherein said 7-day compressive strength is at least about 1800 psi.

144 . The LWC of claim 143 ,

wherein said LWC has a 28-day compressive strength of at least about 3000 psi.

145 . The LWC of claim 143 ,

wherein said LWC has a 28-day compressive strength of at least about 3800 psi.

145 . A LWC, comprising

one or more cementitious materials;

one or more ordinary aggregates; and

one or more LWA;

wherein said LWC has a 7-day compressive strength in psi and an oven-dried density in lb./cu. ft; and

wherein a ratio of said 7-day compressive strength and said density is above about 30.

146 . The LWC of claim 145 ,

wherein said ratio is above about 45.

147 . The LWC of claim 145 ,

wherein said LWC has a 28-day compressive strength in psi; and

wherein a ratio of said 28-day compressive strength and said density is above about 65.

148 . The LWC of claim 147 ,

said one or more LWA comprising glass microspheres; and

said glass microspheres having a specific gravity of about 0.35.

149 . The LWC of claim 145 ,

wherein said 7-day compressive strength is at least about 2500 psi.

150 . The LWC of claim 147 ,

wherein said 28-day compressive strength is at least about 3800 psi.

151 . The LWC of claim 145 ,

wherein said density is less than about 60.

152 . The LWC of claim 145 ,

said one or more ordinary aggregates comprising a coarse aggregate; and

wherein said ratio is above about 40.

153 . The LWC of claim 152 ,

wherein said LWC has a 28-day compressive strength in psi; and

wherein a ratio of said 28-day compressive strength and said density is above about 45.

154 . The LWC of claim 145 ,

wherein said 7-day compressive strength is at least about 4500 psi.

155 . The LWC of claim 154 ,

said one or more LWA comprising glass microspheres; and

said glass microspheres having a specific gravity of about 0.35.

156 . The LWC of claim 145 ,

wherein said 28-day compressive strength is at least about 5100 psi.

157 . The LWC of claim 156 ,

wherein said density is less than about 130.

158 . The LWC of claim 145 ,

wherein said density is about 120; and

wherein said 7-day compressive strength is at least about 5100 psi.

159 . The LWC of claim 153 ,

wherein said density is about 120; and

wherein said 28-day compressive strength is at least about 6500 psi; and

said ratio is above about 55.

160 . A LWC composition, comprising:

one or more cementitious materials;

water; and

one or more LWA;

wherein said LWA is closed-cell and non-absorptive;

wherein each of said one or more cementitious materials, water, and one or more aggregates has a volume; and

wherein a volume ratio of the volume of the LWA to a sum of the said volumes is at least about 39%; and

wherein a strength to density ratio of a 7-day compressive strength in psi after curing and an oven-dried density in lb./cu. ft is above about 30.

161 . The LWC of claim 160 ,

wherein said strength to density ratio is above about 40.

162 . The LWC of claim 160 ,

wherein a strength to density ratio of a 28-day compressive strength in psi after curing and said density is above about 45.

163 . The LWC of claim 162 ,

wherein the strength to density ratio of the 28-day compressive strength is above about 70.

164 . The LWC of claim 162 ,

wherein the 28-day compressive strength is at least about 2750 psi.

165 . The LWC of claim 160 ,

wherein said density is less than about 62 lb./cu. ft.

166 . A LWC, comprising

an R-value of at least about 0.4/inch; and

a 7-day compressive strength in psi and an oven-dried density in lb./cu. ft; and

wherein a ratio of said 7-day compressive strength and said density is above about 30.

167 . The LWC of claim 166 ,

further comprising a 28-day compressive strength of at least about 4100 psi.

168 . The LWC of claim 166 , further comprising said R-value being at least about 0.7/inch; and

said 7-day compressive strength being at least about 2200 psi.

169 . The LWC of claim 168 ,

further comprising a 28-day compressive strength of at least about 2500 psi.

170 . The LWC of claim 168 ,

further comprising a 28-day compressive strength of at least about 3700 psi.

171 . The LWC of claim 167 ,

wherein said ratio of said 28-day compressive strength and said density is above about 70.

172 . The LWC of claim 160 ,

further comprising glass microspheres.

173 . The LWC of claim 172 ,

said glass microspheres having a specific gravity of about 0.15.

174 . The LWC of claim 172 ,

said glass microspheres having a specific gravity of about 0.35;

further comprising a 28-day compressive strength in psi; and

wherein a ratio of said 28-day compressive strength and said density is above about 70.

175 . A LWC composition, comprising:

an R-value of at least about 0.7/inch; and

a 28-day compressive strength in psi after curing and an oven-dried density in lb./cu. ft; and

wherein a ratio of said 28-day compressive strength and said density is above about 80.

176 . The LWC composition of claim 175 ,

wherein said ratio is above about 85.

177 . The LWC composition of claim 175 ,

further comprising glass microspheres.

178 . The LWC composition of claim 177 ,

said glass microspheres having a specific gravity of about 0.35.

179 . The LWC composition of claim 175 ,

further comprising a LWA comprising closed-cell and non-absorptive particles.

180 . A concrete composition, comprising:

one or more cementitious materials;

water; and

closed-cell particles;

wherein said composition following substantially complete mixing has a percentage of entrained air less than about 4 percent by volume.

181 . The concrete composition of claim 180 ,

said percentage being less than about 2%.

182 . The concrete composition of claim 180 ,

wherein the particles and the composition each have a volume; and

wherein a ratio of the volume of the particles to the volume of the composition is at least about 5%.

183 . The concrete composition of claim 182 ,

wherein the said ratio is between about 6% and about 20%.

184 . The concrete composition of claim 183 ,

wherein the said ratio is between about 8% and about 12%.

185 . The concrete composition of claim 180 ,

said particles comprising glass microspheres having a specific gravity less than about 0.65.

186 . The concrete composition of claim 180 ,

wherein said particles are non-absorptive and substantially resist volumetric change under compression.

187 . The concrete composition of claim 180 ,

further comprising one or more aggregates.

188 . A concrete composition, comprising:

one or more cementitious materials;

water; and

closed-cell particles;

wherein the particles and the composition each have a volume; and

wherein a ratio of the volume of the particles to the volume of the composition is at least about 5%.

189 . The concrete composition of claim 188

wherein the said ratio is between about 6% and about 20%.

190 . The concrete composition of claim 188

wherein the said ratio is between about 6% and about 15%.

191 . The concrete composition of claim 188 ,

wherein said particles contain a gas.

192 . The concrete composition of claim 188 ,

said particles comprising glass microspheres having a specific gravity less than about 0.65.

193 . The concrete composition of claim 188 ,

wherein said particles substantially resist volumetric change under compression.

194 . The steps of mixing a concrete composition, comprising the steps of:

mixing one or more cementitious materials, water, and closed-cell particles in a mixer;

wherein said composition has a percentage of entrained air less than about 4 percent by volume following substantially complete mixing.

195 . The steps of mixing a concrete composition of claim 194 ,

wherein the particles and the composition following substantially complete mixing each have a volume; and

wherein a ratio of the volume of the particles to the volume of the composition is at least about 5%.

196 . The steps of mixing a concrete composition of claim 194 ,

said percentage being less than about 2%.

197 . The steps of mixing a concrete composition of claim 194 ,

said particles comprising glass microspheres having a specific gravity less than about 0.65.

198 . The steps of mixing a concrete composition of claim 194 ,

said percentage being less than about 1%.

199 . The steps of mixing a concrete composition of claim 194 ,

said mixing step further comprising mixing one or more ordinary aggregates.

200 . The steps of mixing a concrete composition, comprising the steps of:

mixing one or more cementitious materials, water, and closed-cell particles in a mixer;

wherein the particles are substantially volumetrically stable;

wherein the particles and the composition following substantially complete mixing each have a volume; and

wherein a ratio of the volume of the particles to the volume of the composition is at least about 5%.

201 . The steps of mixing a concrete composition of claim 200 ,

wherein the said ratio is between about 6% and about 20%.

202 . The steps of mixing a concrete composition of claim 200 ,

wherein the said ratio is between about 6% and about 15%.

203 . The steps of mixing a concrete composition of claim 200 ,

wherein said particles contain a gas.

204 . The steps of mixing a concrete composition of claim 200 ,

said particles comprising glass microspheres having a specific gravity less than about 0.65.

205 . The steps of mixing a concrete composition of claim 200 ,

said mixing step further comprising mixing one or more ordinary aggregates.