Method for selecting the composition of a construction material comprising an excavated clay soil, method and system for preparing such a construction material
The invention relates to a method ( 100 ) for selecting the composition of a construction material including an excavated clay soil, said construction material composition to include deflocculating agent and activating agent quantities adapted to the excavated clay soil, said method including a step of receiving ( 130 ) a measured value of at least one physicochemical property of an excavated clay soil, and a step of selecting ( 170 ) a deflocculating agent quantity and an activating agent quantity adapted to the excavated clay soil. In addition, the invention also relates to a method ( 200 ) for calibrating a calculation algorithm for determining the composition of a site construction material, to a construction material formed from an excavated clay soil, and to a system ( 400 ) for preparing a construction material including an excavated clay soil.
1. A construction material comprising an excavated raw clay soil, a deflocculating agent and an alkaline activating agent, the alkaline activating agent being a composition including a compound having a pKa greater than or equal to 10.
2. The construction material according to claim 1 , wherein the excavated raw clay soil has not undergone a combustion stage.
3. The construction material according to claim 1 , comprising:
30 to 80 wt % of the excavated raw clay soil,
1 to 10 wt % of the deflocculating agent, and
10 to 50 wt % of the alkaline activating agent.
4. The construction material according to claim 1 , said construction material comprising at least 0.1 wt. % of said deflocculating agent.
5. The construction material according to claim 1 , said excavated raw clay soil comprising a mixture of different types of clays.
6. The construction material according to claim 1 , said construction material comprising at least 2 wt. % metal oxides.
7. The construction material according to claim 6 , said construction material having a water to dry matter weight ratio less than 1.
8. The construction material according to claim 1 , said excavated raw clay soil having particles of a size greater than 50 μm.
9. The construction material according to claim 1 , said deflocculating agent is selected among a nonionic surfactant, an anionic surfactant, a polyacrylate or an amine.
10. The construction material according to claim 1 , further comprising blast furnace slag.
11. The construction material according to claim 10 , comprising:
30 to 80 wt % of the excavated raw clay soil,
0.1 to 10 wt % of the deflocculating agent, and
5 to 10 wt % of the blast furnace slag.
12. The construction material according to claim 1 , said construction material being a construction binder.
13. The construction material according to claim 1 , further comprising at least 2 wt % silt particles.
14. The construction material according to claim 1 , the excavated raw clay soil having 80 wt % or less of particles larger than 2 μm.
15. The construction material according to claim 1 , wherein the excavated raw clay soil includes at least 25 wt % of clay.
16. A site concrete comprising an excavated raw clay soil, a deflocculating agent and an alkaline activating agent, the alkaline activating agent being a composition including a compound having a pKa greater than or equal to 10.
17. The site concrete according to claim 16 , said site concrete comprising at least 10 wt % of the excavated raw clay soil.
18. The site concrete according to claim 16 , said site concrete comprising at least 20 wt % of the excavated raw clay soil.
19. The site concrete according to claim 16 , comprising:
5 to 20 wt % of the excavated raw clay soil;
0.1 to 3 wt % of the deflocculating agent;
3 to 15 wt % of an activating agent;
25 to 45 wt % sand; and
35 to 55 wt % aggregates.
20. The site concrete according to claim 16 , said site concrete including at least one of the following: plasticizers, superplasticizers, rheological retention agents or air-entraining agents.