Non-flowable quick-setting phosphate cement repair material with strong cohesive forces and preparation method thereof

Abstract

The present invention belongs to the field of composite materials, and particularly to a non-flowable quick-setting phosphate cement repair material with strong cohesive forces and the preparation method thereof. The material comprises the following raw materials in percentage by weight: 20% to 40% of sand, 5% to 12% of ammonium dihydrogen phosphate, 10% to 25% of magnesium oxide, 2% to 8% of fly ash, 30% to 60% of rubber powder, 6% to 10% of silica fume, 0.35% to 0.6% of a polycarboxylate high efficiency water-reducing agent, 1% to 5% of sodium silicate, 1.5% to 2% of a polypropylene fiber, 0.5% to 2% of a retarder, and 8% to 10% of water. The material is used as the repair material for the special positions of bottom boards of bridges or facades of buildings which are damaged, and the repair effect thereof is remarkable.

Claims

1. A non-flowable quick-setting phosphate cement repair material with cohesive forces, wherein the phosphate cement repair material comprises the following raw materials in percentage by weight: 20% to 40% of sand, 5% to 12% of ammonium dihydrogen phosphate, 10% to 25% of magnesium oxide, 2% to 8% of fly ash, 30% to 60% of rubber powder, 6% to 10% of silica fume, 0.35% to 0.6% of a polycarboxylate water-reducing agent, 1% to 5% of sodium silicate, 1.5% to 2% of a polypropylene fiber, 0.5% to 2% of a retarder, and 8% to 10% of water.

2. The phosphate cement repair material of claim 1, wherein the sand is medium sand having a fineness modulus of 2.5, a mud content of 0.8%, no clod, and an apparent density of 2700 kg/m.sup.3.

3. The phosphate cement repair material of claim 1, wherein the retarder is borax.

4. The phosphate cement repair material of claim 1, wherein the phosphate cement repair material comprises the following raw materials in percentage by weight: 25% of sand, 5% of ammonium dihydrogen phosphate, 20% of magnesium oxide, 2% of fly ash, 30% of rubber powder, 6% of silica fume, 0.4% of a polycarboxylate water-reducing agent, 1.6% of sodium silicate, 1.5% of a polypropylene fiber, 0.5% of a retarder, and 8% of water.

5. The phosphate cement repair material of claim 1, wherein the phosphate cement repair material comprises the following raw materials in percentage by weight: 20% of sand, 6% of ammonium dihydrogen phosphate, 18% of magnesium oxide, 3% of fly ash, 32% of rubber powder, 7% of silica fume, 0.5% of a polycarboxylate water-reducing agent, 1.5% of sodium silicate, 2% of a polypropylene fiber, 1% of a retarder, and 9% of water.

6. The phosphate cement repair material of claim 1, wherein the phosphate cement repair material is prepared by specific steps of successively weighing the ammonium dihydrogen phosphate, magnesium oxide, fly ash, rubber powder, silica fume, polycarboxylate water-reducing agent, sodium silicate, retarder, and sand according to the required weight ratio of the raw materials, then adding them to a mixing drum of a mixer to stir at a constant speed for 5 to 10 minutes until the nine materials are stirred uniformly; slowly adding water of the required weight to the mixing drum and then stirring continuously for 1 to 2 minutes until a uniform pasty slurry with good flowability is formed, and subsequently adding a hollow polypropylene fiber of the desired weight and stirring for 30 seconds.

7. The phosphate cement repair material of claim 2, wherein the phosphate cement repair material is prepared by specific steps of successively weighing the ammonium dihydrogen phosphate, magnesium oxide, fly ash, rubber powder, silica fume, polycarboxylate water-reducing agent, sodium silicate, retarder, and sand according to the required weight ratio of the raw materials, then adding them to a mixing drum of a mixer to stir at a constant speed for 5 to 10 minutes until the nine materials are stirred uniformly; slowly adding water of the required weight to the mixing drum and then stirring continuously for 1 to 2 minutes until a uniform pasty slurry with good flowability is formed, and subsequently adding a hollow polypropylene fiber of the desired weight and stirring for 30 seconds.

8. The phosphate cement repair material of claim 3, wherein the phosphate cement repair material is prepared by specific steps of successively weighing the ammonium dihydrogen phosphate, magnesium oxide, fly ash, rubber powder, silica fume, polycarboxylate water-reducing agent, sodium silicate, retarder, and sand according to the required weight ratio of the raw materials, then adding them to a mixing drum of a mixer to stir at a constant speed for 5 to 10 minutes until the nine materials are stirred uniformly; slowly adding water of the required weight to the mixing drum and then stirring continuously for 1 to 2 minutes until a uniform pasty slurry with good flowability is formed, and subsequently adding a hollow polypropylene fiber of the desired weight and stirring for 30 seconds.

9. The phosphate cement repair material of claim 4, wherein the phosphate cement repair material is prepared by specific steps of successively weighing the ammonium dihydrogen phosphate, magnesium oxide, fly ash, rubber powder, silica fume, polycarboxylate water-reducing agent, sodium silicate, retarder, and sand according to the required weight ratio of the raw materials, then adding them to a mixing drum of a mixer to stir at a constant speed for 5 to 10 minutes until the nine materials are stirred uniformly; slowly adding water of the required weight to the mixing drum and then stirring continuously for 1 to 2 minutes until a uniform pasty slurry with good flowability is formed, and subsequently adding a hollow polypropylene fiber of the desired weight and stirring for 30 seconds.

10. The phosphate cement repair material of claim 5, wherein the phosphate cement repair material is prepared by specific steps of successively weighing the ammonium dihydrogen phosphate, magnesium oxide, fly ash, rubber powder, silica fume, polycarboxylate water-reducing agent, sodium silicate, retarder, and sand according to the required weight ratio of the raw materials, then adding them to a mixing drum of a mixer to stir at a constant speed for 5 to 10 minutes until the nine materials are stirred uniformly; slowly adding water of the required weight to the mixing drum and then stirring continuously for 1 to 2 minutes until a uniform pasty slurry with good flowability is formed, and subsequently adding a hollow polypropylene fiber of the desired weight and stirring for 30 seconds.

Description

DETAILED DESCRIPTION OF EMBODIMENTS

(1) The present invention will be further described below in combination with specific examples.

Example 1

(2) The phosphate cement-based rapid repair material was prepared by firstly adding 5% of ammonium dihydrogen phosphate, 20% of magnesium oxide, 2% of fly ash, 30% of rubber powder, 6% of silica fume, 0.4% of polycarboxylate high efficiency water-reducing agent, 1.6% of sodium silicate, and 0.5% of retarder to a mixer to be uniformly stirred, then feeding 25% of sand to the mixer to be uniformly stirred, followed by adding 8% of water to the mixing drum slowly, continuously stirring for 1 to 2 minutes after water was added completely until a uniform pasty slurry with good flowability was formed, and subsequently adding 1.5% of a polypropylene fiber and stirring for 30 seconds.

(3) The test results of the fly ash were shown in Table 1.

(4) TABLE-US-00001 TABLE 1 The test results of the fly ash. GBJI46-90 Specification requirements Test Items I II III Fly ash Fineness (residue on 45 μm ≤12 ≤20 ≤45 10.9 square hole sieve) (%) Ignition Loss (%) ≤6 ≤8 ≤15 4.65 Water demand (%) ≤95 ≤105 ≤115 89 Sulfur trioxide content (%) ≤3 ≤3 ≤3 1.2

(5) I. The Test Results of Performance of the Phosphate Cement-Based Rapid Repair Material.

(6) 1. Setting Time.

(7) The instruments and apparatus specified in GB1346 “Method for Detecting Water Consumption for Cement Standard Consistency, Setting Time, and Stability of Cement” were used as experimental instruments.

(8) 300 g of the phosphate cement rapid repair material was poured into a mixing pot, 30 g of tap water was added, and stirred quickly to be uniform, the material was immediately placed in a round molds, vibrated for several times, and wiped to dry after removing excess thick slurry, and the initial setting time was determined to be 10 minutes, and the final setting time was 16 minutes.

(9) 2. Compressive Strength.

(10) The phosphate cement rapid repair raw materials were weighed according to the proportions in Example 1, and then poured into a stirring pot and stirred rapidly. After taken out from the pot, it was immediately poured into a 4×4×16 cm.sup.3 test mold, and tamped 20 times with a tamper stick and the test mold was vibrated on the ground for 2 to 3 minutes while wiping the repair material overflowing the surface off with a trowel, and three sample strips in the same test mold were numbered and marked with age and the like. Since the repair material was air-cured, no watering was required. The strengths were tested after 1 hour, 3 hours, 1 day, 7 days, 28 days, 60 days, and 90 days, respectively. The results were shown in Table 2, and the results were the average of three samples.

(11) TABLE-US-00002 TABLE 2 Mechanical property test. Experimental Strength Age materials (MPa) 1 h 3 h 1 d 3 d 7 d 28 d 60 d 90 d Phosphate Bending 5.3 6.1 7.5 8.1 10.2 10.9 11.8 12 rapid repair strength material Compressive 32.2 36.1 52.2 57.1 56.2 72.3 75.8 77.6 Strength Ratio of 0.168 0.17 0.162 0.16 0.162 0.155 0.156 0.155 bending- compressive strength

(12) The one-hour strength had reached 32.2 MPa and the bending strength had reached 5.3 MPa, and 28-day strengths had reached 72.3 MPa and 10.9 MPa, respectively, and both the 60-day and 90-day strengths had grown slowly without reduction phenomenon in strengths. It can be seen that in the sub-zero temperature environment, after repairing the external facade of a wall with this material, the repair material exhibited obvious properties such as non-flowability, quick-setting and rapid-hardening, strong cohesive forces and the like, and its one-hour strength had reached 30 MPa or higher, the bending strength had reached 5 MPa or higher. The specific experimental data were shown in Table 2.

Example 2

(13) The phosphate cement-based rapid repair material comprises 20% of sand, 6% of ammonium dihydrogen phosphate, 18% of magnesium oxide, 3% of fly ash, 32% of rubber powder, 7% of silica fume, 0.5% of a polycarboxylate high efficiency water-reducing agent, 1.5% of sodium silicate, 2% of a polypropylene fiber, 1% of a retarder, and 9% of water.