UHPC (Ultra High Performance Concrete)

Abstract

The invention provides UHPC (Ultra High Performance Concrete). The UHPC is prepared from the following components: PO52.5 cement, silica fume, quartz sand, a water reducing agent, a plastic expanding agent, a defoaming agent and water. On the basis of the maximum bulk density theory, powder with different particle sizes is adopted to form a closest packing structure, and it is ensured that UHPC has excellent mechanical properties such as compressive strength, breaking strength and fracture toughness; the quartz sand is used as an aggregate, so that cracks are prevented from being generated in the concrete in the solidification process, the water consumption is reduced, the workability of a concrete mixture is improved, the quartz sand with the modulus of stone powder is mutually filled, supported and reasonably graded, microdefects in UHPC (Ultra High Performance Concrete) can be reduced, and a cementing material with relatively good stacking compactness is formed; the tensile strength, the bending resistance, the impact resistance, the fatigue resistance and the like of the UHPC material are improved.

Description

Technical Field

[0001] The invention relates to the technical field of concrete, and in particular to UHPC concrete. Background Art

[0002] Ultra-high performance concrete (UHPC) is a cement-based composite material with high strength, high toughness and low porosity. Its mechanical and durability properties are significantly better than those of normal concrete (NSC) and high performance concrete (HPC), while also having excellent workability. The preparation of UHPC is based on the principle of the most compact packing, which maximizes the density of UHPC, while introducing steel fibers to enhance the bending resistance and toughness of UHPC. The UHPC matrix and fibers have a high bond strength, which gives UHPC significant strain hardening properties. These excellent material properties make UHPC widely used in construction engineering, bridge engineering, tunnels and underground engineering. Summary of the invention

[0003] The purpose of the present invention is to provide a UHPC concrete, which adopts powders of different particle sizes to form the most densely packed structure, and introduces steel fibers at the same time, and uses its high tensile strength to limit the development and penetration of cracks in the concrete, thereby ensuring that the prepared UHPC has excellent mechanical properties such as compressive strength, flexural strength and fracture toughness.

[0004] In order to solve the above technical problems, the solution of the present invention is: a UHPC concrete, comprising the following components in parts by weight: 200-700 parts of PO52.5 cement, 0-40 parts of mineral powder, 0-190 parts of fly ash, 0-120 parts of silica fume, 0-1000 parts of rapid hardening cement, 360-1200 parts of quartz sand mixture, 0.5-8 parts of water reducer, 0-150 parts of fiber, 0-0.9 parts of plastic expansion agent, 0-0.9 parts of defoamer, 0-0.4 parts of cellulose ether, and 95-900 parts of water.

[0005] Preferably, the quartz sand mixture consists of quartz sand of 10-20 mesh, 20-40 mesh, 40-70 mesh and 70-140 mesh.

[0006] Preferably, 200 parts of PO52.5 cement, 360 parts of quartz sand mixture, 0.5 parts of water reducer, and 95 parts of water.

[0007] Preferably, 500 parts of PO52.5 cement, 20 parts of mineral powder, 100 parts of fly ash, 60 parts of silica fume, 500 parts of rapid hardening cement, 700 parts of quartz sand mixture, 4 parts of water reducer, 70 parts of fiber, 0.5 parts of plastic expansion agent, 0.5 parts of defoaming agent, 0.2 parts of cellulose ether, and 450 parts of water.

[0008] Preferably, PO52.5 cement 700 parts, 40 parts, fly ash 190 parts, silica fume 120 parts, rapid hardening cement 1000 parts, quartz sand mixture 1200 parts, water reducer 8 parts, fiber 150 parts, plastic expansion agent 0.9 parts, defoamer 0.9 parts, cellulose ether 0.4 parts, water 900 parts.

[0009] Preferably, the silica fume is S95 grade silica fume.

[0010] Preferably, the water reducer is a 1051 grade polycarboxylate water reducer.

[0011] Preferably, the plastic expansion agent is an AC plastic expansion agent.

[0012] Compared with the prior art, the beneficial effects of the present invention are as follows: based on the maximum packing density theory, powders of different particle sizes are used to form the most densely packed structure, ensuring that UHPC has excellent mechanical properties such as compressive strength, flexural strength and fracture toughness; quartz sand is used as aggregate to avoid cracks in the concrete during the solidification process, reduce water consumption, and improve the workability of the concrete mixture; quartz sand with a stone powder modulus, mutual filling and support, and reasonable grading can reduce the generation of micro defects in UHPC and form a cementitious material with good packing density; and the tensile, bending, impact and fatigue resistance of the UHPC material are improved. DETAILED DESCRIPTION

[0013] The specific embodiments of the present invention are further described below. It should be noted that the description of these embodiments is used to help understand the present invention, but does not constitute a limitation of the present invention. In addition, the technical features involved in each embodiment of the present invention described below can be combined with each other as long as they do not conflict with each other.

[0014] Example 1

[0015] A UHPC concrete comprising the following components in parts by weight:

[0016]

[0017] Example 2

[0018] A UHPC concrete comprising the following components in parts by weight:

[0019]

[0020] Example 3

[0021] A UHPC concrete comprising the following components in parts by weight:

[0022]

[0023] Example 4

[0024] A UHPC concrete comprises the following components in parts by weight:

[0025]

[0026] Example 5

[0027] A UHPC concrete comprising the following components in parts by weight:

[0028]

[0029] Example 6

[0030] A UHPC concrete comprising the following components in parts by weight:

[0031]

[0032] Example 7

[0033] A UHPC concrete comprising the following components in parts by weight:

[0034]

[0035] Example 8

[0036] A UHPC concrete comprising the following components in parts by weight:

[0037]

[0038] Example 9

[0039] A UHPC concrete comprising the following components in parts by weight:

[0040]

[0041] Example 10

[0042] A UHPC concrete comprising the following components in parts by weight:

[0043]

[0044] Embodiment 11

[0045] A UHPC concrete comprising the following components in parts by weight:

[0046] Example 12

[0047] A UHPC concrete comprising the following components in parts by weight:

[0048]

[0049] Example 13

[0050] A UHPC concrete comprising the following components in parts by weight:

[0051]

[0052] Embodiment 14

[0053] A UHPC concrete comprising the following components in parts by weight:

[0054]

[0055] Embodiment 15

[0056] A UHPC concrete comprising the following components in parts by weight:

[0057]

[0058] Example 16

[0059] A UHPC concrete comprising the following components in parts by weight:

[0060]

[0061] Embodiment 17

[0062] A UHPC concrete comprising the following components in parts by weight:

[0063]

[0064] Embodiment 18

[0065] A UHPC concrete comprising the following components in parts by weight:

[0066] Embodiment 19

[0067] A UHPC concrete comprising the following components in parts by weight:

[0068]

[0069] Embodiment 20

[0070] A UHPC concrete comprising the following components in parts by weight:

[0071] Embodiment 21

[0072] A UHPC concrete comprising the following components in parts by weight:

[0073]

[0074] Embodiment 22

[0075] A UHPC concrete comprising the following components in parts by weight:

[0076] Embodiment 23

[0077] A UHPC concrete comprising the following components in parts by weight:

[0078]

[0079] Embodiment 24

[0080] A UHPC concrete comprising the following components in parts by weight:

[0081]

[0082] Embodiment 25

[0083] A UHPC concrete comprising the following components in parts by weight:

[0084]

[0085] Embodiment 26

[0086] A UHPC concrete comprising the following components in parts by weight:

[0087] Embodiment 27

[0088] A UHPC concrete comprising the following components in parts by weight:

[0089]

[0090] Embodiment 28

[0091] A UHPC concrete comprising the following components in parts by weight:

[0092]

[0093] Embodiment 29

[0094] A UHPC concrete comprising the following components in parts by weight:

[0095]

[0096] Embodiment 30

[0097] A UHPC concrete comprising the following components in parts by weight:

[0098]

[0099] Embodiment 31

[0100] A UHPC concrete comprising the following components in parts by weight:

[0101]

[0102] Embodiment 32

[0103] A UHPC concrete comprising the following components in parts by weight:

[0104]

[0105] Embodiment 33

[0106] A UHPC concrete comprising the following components in parts by weight:

[0107]

[0108] Embodiment 34

[0109] A UHPC concrete comprising the following components in parts by weight:

[0110] Embodiment 35

[0111] A UHPC concrete comprising the following components in parts by weight:

[0112]

[0113] Embodiment 36

[0114] A UHPC concrete comprising the following components in parts by weight:

[0115]

[0116] Embodiment 37

[0117] A UHPC concrete comprising the following components in parts by weight:

[0118]

[0119] Embodiment 38

[0120] A UHPC concrete comprising the following components in parts by weight:

[0121]

[0122] Embodiment 39

[0123] A UHPC concrete comprising the following components in parts by weight:

[0124]

[0125] Embodiment 40

[0126] A UHPC concrete comprising the following components in parts by weight:

[0127]

[0128] Embodiment 41

[0129] A UHPC concrete comprising the following components in parts by weight:

[0130]

[0131] In summary, from the experimental records of the above embodiments 1-41, it can be seen that when the cement is 515kg, the fly ash is 100kg, the silica fume is 15kg, the quick-hardening cement is 10kg, the 10-20 mesh quartz sand is 72kg, the 20-40 mesh quartz sand is 144kg, the 40-70 mesh quartz sand is 72kg, the 70-120 mesh quartz sand is 72kg, the water reducer is 3kg, the plastic expansion agent is 0.4kg, the defoaming agent is 0.8kg, and the water is 96kg, the flexural strength is 26.5 / 22.3 / 24MPa, and the average flexural strength is 24MPa; the compressive strength is 149.86 / 139.39MPa.

[0132] When the cement is 650kg, the fly ash is 40kg, the silica fume is 190kg, the quick-hardening cement is 20kg, the 10-20 mesh quartz sand is 220kg, the 20-40 mesh quartz sand is 480kg, the 40-70 mesh quartz sand is 300kg, the 70-120 mesh quartz sand is 200kg, the water reducer is 8kg, the fiber is 110kg, the defoaming agent is 0.5kg, and the water is 175kg, the flexural strength is 26.5 / 22.3 / 24MPa, and the average flexural strength is 24MPa; the compressive strength is 149.86 / 139.39MPa.

[0133] When the cement is 420kg, the fly ash is 100kg, the silica fume is 25kg, the quick-hardening cement is 5kg, the 10-20 mesh quartz sand is 85kg, the 20-40 mesh quartz sand is 140kg, the 40-70 mesh quartz sand is 140kg, the 70-120 mesh quartz sand is 85kg, the water reducer is 3kg, the plastic fiber is 0.4kg, the defoaming agent is 0.6kg, and the water is 95kg, the flexural strength is 23.4 / 25MPa; the compressive strength is 159 / 132MPa, 156.9 / 137MPa, and 130 / 138MPa.

[0134] The above are the best embodiments.

[0135] Specifically, the silica fume is S95 grade silica fume, which has extremely high activity and can react with cement hydration products to generate a denser structure.

[0136] Furthermore, the water reducing agent is a 1051 grade polycarboxylate water reducing agent, which reduces the water-binder ratio and improves the strength and durability of concrete.

[0137] Specifically, the plastic expansion agent is an AC plastic expansion agent.

[0138] The principle of the present invention is to use the control variable method to accurately study the influence of various factors on the performance of UHPC, so as to obtain the above formula and provide a scientific basis for the preparation of UHPC concrete. The formula studied by the present invention can optimize the performance of UHPC, so that it has higher strength, better toughness and durability. It reduces the blind experiments in the traditional preparation method, improves the research and development and production efficiency, and reduces the cost. It ensures that the prepared UHPC has stable performance and reliable quality, and is suitable for various engineering applications.

[0139] The embodiments of the present invention are described in detail above, but the present invention is not limited to the described embodiments. For those skilled in the art, various changes, modifications, substitutions and variations of these embodiments are made without departing from the principles and spirit of the present invention, and still fall within the protection scope of the present invention.

Claims

1. A UHPC concrete, characterized in that: The invention comprises the following components in parts by weight: 200-700 parts of PO52.5 cement, 0-40 parts of mineral powder, 0-190 parts of fly ash, 0-120 parts of silica fume, 0-1000 parts of rapid hardening cement, 360-1200 parts of quartz sand mixture, 0.5-8 parts of water reducer, 0-150 parts of fiber, 0-0.9 parts of plastic expansion agent, 0-0.9 parts of defoaming agent, 0-0.4 parts of cellulose ether and 95-900 parts of water.

2. The UHPC concrete according to claim 1, characterized in that: The quartz sand mixture consists of quartz sands of 10-20 mesh, 20-40 mesh, 40-70 mesh and 70-140 mesh.

3. The UHPC concrete according to claim 1, characterized in that: It contains the following components in parts by weight: 200 parts of PO52.5 cement, 360 parts of quartz sand mixture, 0.5 parts of water reducing agent, and 95 parts of water.

4. The UHPC concrete according to claim 1, characterized in that: It contains the following components in parts by weight: 500 parts of PO52.5 cement, 20 parts of mineral powder, 100 parts of fly ash, 60 parts of silica fume, 500 parts of quick-hardening cement, 700 parts of quartz sand mixture, 4 parts of water reducer, 70 parts of fiber, 0.5 parts of plastic expansion agent, 0.5 parts of defoaming agent, 0.2 parts of cellulose ether, and 450 parts of water.

5. The UHPC concrete according to claim 1, characterized in that: It contains the following components in parts by weight: 700 parts of PO52.5 cement, 40 parts, 190 parts of fly ash, 120 parts of silica fume, 1000 parts of quick-hardening cement, 1200 parts of quartz sand mixture, 8 parts of water reducer, 150 parts of fiber, 0.9 parts of plastic expansion agent, 0.9 parts of defoaming agent, 0.4 parts of cellulose ether, and 900 parts of water.

6. The UHPC concrete according to claim 1, characterized in that: The silica fume is S95 grade silica fume.

7. The UHPC concrete according to claim 1, characterized in that: The water reducer is a 1051 grade polycarboxylate water reducer.

8. The UHPC concrete according to claim 1, characterized in that: The plastic expansion agent is an AC plastic expansion agent.

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