Ultra-high performance concrete

Abstract

A hydraulic composition includes in relative parts by mass with respect to the cement 100 parts of cement the particles of which have a BET specific surface area comprised from 1.20 to 5 m.sup.2/g; 32 to 42 parts of water; 5 to 50 parts of a mineral addition A1 the particles of which have a D50 less than or equal to 6 ?m and selected from silica fume, metakaolin, slag, pozzolans or mixtures thereof; 90 to 230 parts of sand the particles of which have a D50 greater than or equal to 50 ?m and a D90 less than or equal to 3 mm; 0.0001 to 10 parts of a superplasticizer, the active material concentration of which is 15% by mass.

Claims

1. A hydraulic composition comprising in relative parts by mass with respect to the cement: 100 parts of cement the particles of which have a BET specific surface area comprised from 1.20 to 5 m.sup.2/g; 32 to 42 parts of water; 5 to 50 parts of a mineral addition A1 the particles of which have a D50 less than or equal to 6 ?m and selected from silica fume, metakaolin, slag, pozzolans or mixtures thereof; 90 to 230 parts of sand the particles of which have a D50 greater than or equal to 50 ?m and a D90 less than or equal to 3 mm; 0.0001 to 10 parts of a superplasticizer.

2. The hydraulic composition according to claim 1, comprising in relative parts by mass with respect to the cement: 100 parts of cement the particles of which have a BET specific surface area comprised from 1.20 to 1.7 m.sup.2/g; 38 to 42 parts of water; 8 to 20 parts of a mineral addition A1 the particles of which have a D50 less than or equal to 6 ?m and selected from silica fume, metakaolin, slag, pozzolans or mixtures thereof; 90 to 180 parts of sand the particles of which have a D50 comprised from 100 ?m to 400 ?m and a D90 less than or equal to 800 ?m; 0.0001 to 10 parts of a superplasticizer, the active material concentration of which is 15% by mass.

3. The hydraulic composition according to claim 1, further comprising from 0.001 to 2 parts of a viscosity-modifying agent expressed in relative parts by mass with respect to the cement.

4. The hydraulic composition according to claim 1, wherein the cement is a CEM I cement.

5. The hydraulic composition according claim 1, further comprising from 0 to 300 parts of a mineral addition A2, differing from A1, the particles of which have a D50 comprised from 1 ?m to 50 ?m, expressed in relative parts by mass with respect to the cement.

6. The hydraulic composition according to claim 1, further comprising from 0 to 10 parts of anhydrous calcium sulfate expressed in relative parts by mass with respect to the cement.

7. The hydraulic composition according to claim 1, further comprising mineral fibers, organic fibers or metal fibers or a mixture thereof.

8. The hydraulic composition according to claim 1, further comprising from 0 to 0.5 parts of antifoaming agent expressed in relative parts by mass with respect to the cement.

9. A method for producing a hydraulic composition according to claim 1, comprising mixing the cement, additions, sand, water and superplasticizer are mixed.

10. An object formed for the field of construction comprising the hydraulic composition according to claim 1.

11. A method for manufacturing an object for the field of construction comprising: (i) preparing a hydraulic composition according to claim 1; (ii) applying the composition prepared at step (i) to a support.

12. The production method according to claim 11, further comprising a mould release step (iii) after hardening of the hydraulic composition.

13. The production method according to claim 11, further comprising a step to pump the hydraulic composition after step (i).

14. The production method according to claim 11, wherein the support at step (i) is a mould, a wall, a partition or a floor.

15. The production method according to claim 11, wherein step (ii) is performed by projecting the hydraulic composition.

16. A method for manufacturing an object for the field of construction comprising: (i) preparing a hydraulic composition according to claim 2; (ii) applying the composition prepared at step (i) to a support, wherein step (ii) is performed by spraying the hydraulic composition.

17. A method for manufacturing an object for the field of construction comprising: (i) preparing a hydraulic composition according to claim 3; (ii) applying the composition prepared at step (i) to a support, characterized in that step (ii) is performed by casting or calendering the hydraulic composition.

Description

EXAMPLES

(1) Raw Materials

(2) Cement No 1 was a Portland CEM I, 52.5 N CE CP2 NF cement supplied by Lafarge, Saint Pierre La Cour. This cement was prepared by pneumatic classification using a very high fineness TSV 1000 separator. The principle is to separate a starting population into 2 fractions (even 3 if ultra-fines are considered separately): one fraction formed of the coarsest particles of the starting product, called rejects, one fraction formed of the finest particles of the starting product. The rotation speed of the selector and air flow rate were set to obtain separation of the particles of desired particle size. The characteristics of the particles in the cement obtained are given in following Table 1:

(3) TABLE-US-00001 TABLE 1 BET specific surface area in m.sup.2/g D10 in ?m D50 in ?m D90 in ?m Cement No1 1.05 2.56 15.47 42.58 1.7 1.73 8.05 21.97 4.45 1.35 5.53 13.22

(4) Cement No 2 was a Portland CEM I, 52.5 N CE PM ES NF cement supplied by Lafarge, Le Teil. This cement was prepared by pneumatic classification using a separator with opposing air jets: ALPINE 200 AFG. The principle is to separate a starting population into 2 fractions (even 3 if ultra-fines are considered separately):one fraction formed of the coarsest particles in the starting product, called rejects, and one fraction formed of the finest particles of the starting product. The rotation speed of the selector and air flow rate were set to obtain separation of the particles with the desired particle size. The characteristics of the particles in the cement obtained are summarized in following Table 2:

(5) TABLE-US-00002 TABLE 2 BET specific surface area in m.sup.2/g D10 in ?m D50 in ?m D90 in ?m Cement No2 1.25 1.92 7.98 19.08 1.6 1.42 7.08 18.01 1.85 1.34 5.25 10.99

(6) The water used was mains water.

(7) The mineral addition A1 was either: metakaolin supplied by Lavollee SA and sold under the trade name MOtamax, the particles of which have a D50 of 4.4 ?m; or silica fume supplied by Saint Gobain, sold under the trade name SEPR Le Pontet and, the particles of which have a D50 of 3 ?m

(8) BE01 sand is a siliceous sand certified conforming to European standard NF EN 196-1 of April 2006, supplied by Sibelco and, the particles of which have a D10 comprised from 210 ?m, D50 of 313 ?m and a D90 of 410 ?m;

(9) The superplasticizer containing modified polycarboxlic ether was Prelom 300 by BASF the dry extract concentration of which is 15% by mass;

(10) The mineral addition A2 was either:

(11) siliceous filler supplied by Sibelco, sold under the trade name Millisil C6 and the particles of which have a D50 of 35 ?m; calcium carbonate supplied by Omya, sold under the trade name Durcal 1 and the particles of which have a D50 of 2.6 ?m;

(12) The anti-foaming agent was Dehydran supplied by Cognis, the dry extract concentration of which is 100%, mass percentage.

(13) The anhydrous calcium sulfate (called anhydrite in Table 3) was obtained from Anhydrite Min?rale France, sold under the trade name Anhydrite Micro A.

(14) The viscosity-modifying agent (called VMA in Table 3) was a diutan gum: Kelcocrete by Kelco the dry extract concentration of which is 100%, mass percentage;

(15) The latex was an aqueous dispersion of fine particles of copolymers of styrene-butadiene type, supplied by Chryso under the trade name Chryso? Cim the dry extract concentration of which is 50%, mass percentage.

(16) Equipment positive displacement pump of eccentric screw type supplied by Power Sprays under the trade name PS9000; Rh?olab QC rheometer, viscosimeter, sold by Anton Paar; a kneader-mixer RAYNERI R601, which was provided by VMI with a tank of 10 liters. This kneader exerts a planetary rotary movement; cylindrical cardboard molds with a diameter of 7 cm and a height of 14 cm; humidity cabinet 95-100% relative hygrometry and 90? C.+/?1? C. provided by Verre Labo Mula; a humid chamber with 95-100% relative hygrometry and 20+/?1? C.

Example 1

(17) The hydraulic compositions of the invention (mixes 202 to 209, and mix 238, 303 and 308) were prepared and compared with a control composition (mix 309). Table 3 below describes the prepared compositions. In this Table 3, the unit is a relative part by mass with respect to the cement.

(18) TABLE-US-00003 TABLE 3 Hydraulic compositions Mix 309 303 208 202 203 204 205 206 207 209 238 308 Cement N? 1 100 100 100 N? 2 100 100 100 100 100 100 100 100 100 BET Cement (m2/g) 1.05 4.45 1.7 1.6 1.6 1.6 1.6 1.6 1.85 1.6 1.25 1.25 A1 Metakaolin 11 11 11 11 11 11 11 11 11 11 11 11 Silica fume 0 0 0 0 0 5 0 0 0 0 0 0 A2 Siliceous: C6 267 0 0 0 267 267 0 0 0 0 0 0 Limestone: Durcal1 0 0 0 0 0 0 270 0 0 0 0 0 Sand Be01 109 109 109 109 109 137 109 109 109 109 109 185 anhydrite 0 5.45 2.59 2.41 2.41 2.41 2.41 2.41 4.32 2.41 1.93 1.93 VMA 0 0 0 0 0 0 0 0 0 0.1 0 0 WATER 40 40.4 40.3 40.0 40.6 40 41.1 40.2 40.6 41.7 39.7 35.4 Superplasticizer Prelom 300 1.1 3.5 1.4 1.1 2 2 2.8 1.3 1.8 3.7 0.7 1.6 Anti-foaming agent Dehydran 0.06 0.06 0.06 0.06 0.06 0.06 0.06 0.06 0.06 0.06 0.06 0.06

(19) The concrete was produced following the protocol described below: 1) charging the dry materials in the drum of the Rayneri kneader-mixer; 2) from 0 to 60 seconds: initiation of slow speed kneading (15 rpm) to homogenise the premix; 3) from 1 min to 1 minute 30 s: adding the mixing water+admixture in 30 seconds, at a rotation speed of 15 rpm; 4) from 1 minute 30 s to 2 minutes 30 seconds: slow speed kneading (15 rpm); 5) from 2 minutes 30 seconds to 6 minutes: high speed kneading (45 rpm).

(20) Stress threshold and compressive strength (CS) were measured following the above-described protocols. Table 4 below gives the results obtained.

(21) TABLE-US-00004 TABLE 4 Results for stress threshold and compressive strength. Stress threshold at 0.1 s?1 in CS at 28 days Mix N? Pa (at t = 7 min) in Mpa 202 285 99.6 203 106 117.6 204 175 111.2 205 147 112.4 206 134 90.8 207 221 97.3 208 222 98.2 209 86 102.5 238 263 102.3 303 178 99.1 308 61 123.8 309 104 85.5