Structural lightweight concrete comprising waste plastics

2:

• The method of claim 1, wherein the waste plastic pieces are in the form of granules, fibers, and/or flakes.

3:

• The method of claim 2, wherein the waste plastic pieces are in the form of granules having a cylindrical shape with an average diameter of 1-4 mm and an average length of 1-7 mm.

4:

• The method of claim 2, wherein the waste plastic pieces are in the form of flakes having an average thickness of 0.3-0.8 mm and an average longest dimension of 1-8 mm.

5:

• The method of claim 2, wherein the waste plastic pieces are in the form of fibers having an average diameter of 0.2-0.8 mm and an average length of 2-12 mm.

6:

• The method of claim 1, wherein the waste plastic pieces have a specific gravity of 0.80-1.20.

7:

• The method of claim 1, wherein the waste plastic pieces have a surface roughness Ra of 1-50 μm.

8:

• The method of claim 1, further comprising reshaping the waste plastic pieces by melting, extruding, or grinding.

9:

• The method of claim 1, wherein the waste plastic pieces comprise 20-100 wt % polyethylene, relative to a total weight of the weight plastic pieces.

10:

• The method of claim 1, wherein the wet concrete slurry further comprises 0.1-2.0 wt % of a superplasticizer relative to a total weight of the wet concrete slurry.

11:

• The method of claim 10, wherein the superplasticizer is a polycarboxylate ether.

12:

• The method of claim 10, wherein the wet concrete slurry has a slump of 50-150 mm.

13:

• The method of claim 1, wherein the Portland cement is an ASTM C 150 cement selected from the group consisting of Type I, Type Ia, Type II, Type IIa, Type II(MH), Type II(MH)a, Type III, Type IIIa, and Type IV.

14:

• The method of claim 1, wherein the fine aggregate is sand with an average particle size of less than 1.5 mm.

15:

• The method of claim 1, wherein the coarse aggregate further comprises at least one selected from the group consisting of limestone, perlite, and scoria, at a weight percentage of 1-90 wt % relative to a total weight of the coarse aggregate.

16:

• The method of claim 15, wherein limestone is present, having an average particle size of 1-20 mm.

17:

• The method of claim 1, wherein the structural lightweight concrete has a compressive strength of 20-40 MPa.

18:

• The method of claim 1, wherein the structural lightweight concrete has a thermal conductivity of 0.50-1.10 W/(m·K).

19:

• The method of claim 1, wherein the structural lightweight concrete has a unit weight of 1,400-2,000 kg/m3.

20:

• The method of claim 1, wherein the structural lightweight concrete does not comprise fly ash.