Ultra-high performance concrete segment

Abstract

The present invention provides an ultra-high performance concrete segment, including a segment body, the segment body is made of ultra-high performance concrete, at least two bolt holes are arranged around the segment body, a plurality of bolt slots are arranged at the bottom of the segment body, the bolt holes correspond to the bolt slots one by one, the two ends of the bolt holes extend to the side wall of the segment body and the slot wall of the bolt slot, a steel bar assembly is arranged in the segment body, the steel bar assembly consists of frame steel bars and reinforcing steel bars, the frame steel bars are arranged along the edge of the segment body, and the reinforcing steel bars are arranged around the bolt holes and the bolt slots. The present invention uses ultra-high performance concrete as the main material of the segment, and utilizes the characteristics of ultra-high performance concrete material with strong compression, tension and flexural resistance and high toughness, so as to enhance the segment's ability to resist soil pressure and water pressure, and is only equipped with a very small amount of steel bars, which reduces the material consumption, reduces the dead weight of the segment, and facilitates the lifting, transportation and construction of the segment.

Description

Technical Field

[0001] The present invention relates to the technical field of tunnel construction, and in particular to an ultra-high performance concrete segment. Background Art

[0002] At present, the construction of highway and subway tunnels generally uses the shield method. During the process of shield equipment excavating the earth in the tunnel, the segments need to be positioned and installed to form a complete shield segment structure. As the innermost supporting structure of the tunnel, the segments bear the soil pressure and groundwater pressure in the tunnel, which directly affects the safety and durability of the tunnel structure.

[0003] In the prior art, the pipe segments are mostly reinforced concrete structures. After the steel cage is woven, concrete is poured. Since ordinary concrete has low tensile strength, most of the tensile strength is provided by the steel bars in the concrete. This makes the thickness of the pipe segments very large, usually more than 300 mm, and the deadweight is generally greater than 2.8 tons. The raw material consumption is huge, but the mechanical properties are ordinary. In addition, the pipe segments are arc-shaped rectangular structures, and the corners are easily damaged during transportation, which will affect the impermeability of the overall structure after installation. Summary of the invention

[0004] In view of the deficiencies of the prior art, the technical problem to be solved by the present invention is how to reduce the use of raw materials for the pipe segments, facilitate on-site construction, and improve their mechanical properties.

[0005] The present invention provides an ultra-high performance concrete segment, comprising a segment body, wherein the segment body is made of ultra-high performance concrete, at least two bolt holes are arranged around the segment body, a plurality of bolt grooves are arranged at the bottom of the segment body, the bolt holes correspond to the bolt grooves one by one, both ends of the bolt holes extend to the side wall of the segment body and the groove wall of the bolt groove, a steel bar assembly is arranged in the segment body, the steel bar assembly consists of frame steel bars and reinforcing steel bars, the frame steel bars are arranged along the edge of the segment body, and the reinforcing steel bars are arranged around the bolt holes and the bolt grooves.

[0006] The present invention uses ultra-high performance concrete as the main material of the pipe segment, and utilizes the characteristics of the ultra-high performance concrete material, such as strong compression resistance, tension resistance, flexural resistance and high toughness, to enhance the ability of the pipe segment to resist soil pressure and water pressure. It is only equipped with a very small amount of steel bars, which reduces the amount of concrete material by half and the amount of steel by 80% compared with traditional pipe segment materials, reduces the dead weight of the pipe segment, and facilitates the lifting, transportation and construction of the pipe segment. The ultra-high performance concrete has a dense structure and is not easy to be damaged. It is not easy for edges, corners and surfaces to be damaged during the construction process, and harmful elements are not easy to enter the interior of the pipe segment, thereby enhancing the durability of the ultra-high performance concrete material, reducing the cost of later maintenance and overhaul, and increasing the overall life of the pipe segment project.

[0007] Furthermore, the material of the segment body is composed of the following raw materials: cement 750-840kg / m 3 , active silicon powder 80-110kg / m 3 , fly ash microbeads 120-210kg / m 3 , crushed stone 0-200kg / m 3 , sand 960-1160kg / m 3 , steel fiber 60-100kg / m 3 , plastic fiber 0-5kg / m 3 , water 190-240kg / m 3 , water reducing agent 15-40kg / m 3 , expansion agent 0-20kg / m 3 .

[0008] Compared with ordinary concrete, the ultra-high performance concrete prepared from the above raw material components has ultra-high compressive strength and axial tensile strength. Ultra-high compressive strength is the basis of all mechanical properties. Ultra-high axial tensile strength increases the bending resistance of the segment, so the thickness of the segment can be reduced, meeting the construction requirements of the segment while reducing the use of concrete raw materials; good toughness and impermeability indicate that the segment has extremely high durability; the good expansion and fluidity of ultra-high performance concrete are suitable for the pumping and laying of the segment, improving production efficiency; and the structure of the ultra-high performance concrete segment is denser than that of ordinary concrete, which inhibits harmful components from entering the interior of the ultra-high performance concrete, improving the durability of the ultra-high performance concrete material, and the dense structure and ultra-high strength of the ultra-high performance concrete also avoid damage during transportation. After the segment is installed, it has excellent waterproof performance, eliminating phenomena such as water seepage.

[0009] Furthermore, the specific surface area of ​​the active silicon powder is greater than or equal to 10000m 2 / kg. Active silica powder can improve many aspects of concrete performance, such as significantly improving the adhesion and cohesion of plastic concrete, and greatly reducing the rebound amount. Active silica powder with a high specific surface area is more active and has a significant performance improvement effect.

[0010] Furthermore, the particle size of the fly ash microbeads is greater than or equal to 170 meshes. The fly ash microbeads can increase the fluidity of the concrete system, and the fly ash microbeads with a high mesh number are more active.

[0011] Furthermore, the particle size of the crushed stone is less than or equal to 10 mm. The addition of crushed stone makes the aggregate structure of the concrete system more reasonable and achieves high-density stacking.

[0012] Furthermore, the plastic fiber is selected from one or more of polypropylene fiber, polyvinyl alcohol fiber, polyethylene plastic steel fiber. The plastic fiber can increase the axial tensile strength of ultra-high performance concrete.

[0013] Furthermore, the water reducing agent is a polycarboxylic acid water reducing agent, and the water reducing rate is greater than or equal to 40%. The water reducing agent can reduce the water-cement ratio of the concrete system and increase the strength.

[0014] Furthermore, the expansion agent is a compound expansion agent of MEA expansion agent and CSA expansion agent, the activity index of the MEA expansion agent is less than or equal to 120s, and the CaO content in the CSA expansion agent is greater than or equal to 55%. The expansion agent can inhibit the shrinkage of concrete and avoid cracking. The compound expansion agent has high activity and good effect of inhibiting concrete shrinkage at an early stage.

[0015] The functions of the various raw materials of ultra-high performance concrete segments are as follows:

[0016] The micro-aggregate effect of fly ash microbeads and active silica powder makes the structure of ultra-high performance concrete more reasonable; the fiber material is a compound of steel fiber and plastic fiber. The addition of fiber material greatly improves the compression, bending and cracking resistance of ultra-high performance concrete; the water-reducing agent greatly reduces the water-cement ratio of the concrete system and improves the compressive strength of ultra-high performance concrete; the addition of expansive agent avoids early shrinkage cracking of ultra-high performance concrete.

[0017] Compared with ordinary concrete segments, the ultra-high performance concrete segments can support the segment skeleton only by the ultra-high performance concrete material itself, which can greatly reduce the steel bars in the segment body. Only the outermost frame steel bars and the reinforcing steel bars around the bolt holes and bolt grooves need to be retained, which saves the use of raw materials, reduces the weight of the segments, and facilitates the lifting, transportation and construction of the segments.

[0018] Furthermore, the thickness of the segment body is 100mm-150mm.

[0019] Ultra-high performance concrete materials have excellent compression and bending resistance, which allows the thickness of ultra-high performance concrete segments to be designed to be smaller than that of ordinary segments, greatly reducing the use of raw materials such as cement and facilitating on-site construction.

[0020] Furthermore, a raised fillet is provided on the front side wall of the tube segment body, and a recessed fillet is provided on the rear side wall of the tube segment body, and the fillet matches the shape of the fillet.

[0021] The front and rear side walls of the segments are respectively provided with embedded strips and embedded grooves for connecting the segments of adjacent rings. The segments of adjacent rings are connected by embedded matching bolts, which makes the connection more reliable, increases the construction efficiency, and simplifies the alignment procedure during the construction of the shield machine. The matching structure of the embedded strips and embedded grooves enhances the connection reliability of the adjacent ring joints, and can also effectively prevent defects in the joints and avoid water seepage from the joints. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] Figure 1 is a schematic diagram of the bottom structure of the ultra-high performance concrete segment in the embodiment;

[0023] Figure 2 is a schematic diagram of the right side structure of the ultra-high performance concrete segment in the embodiment;

[0024] Figure 3 is a schematic diagram of the internal steel bar distribution of the ultra-high performance concrete segment in a top view in an embodiment;

[0025] Figure 4 is a schematic diagram of the internal steel bar distribution in the middle section of the front side of the ultra-high performance concrete segment in the embodiment;

[0026] Figure 5 Schematic diagram of the internal steel bar distribution in the side edge section state of the ultra-high performance concrete segment in the embodiment.

[0027] Description of reference numerals:

[0028] 1-segment body, 2-bolt hole, 3-bolt groove, 4-grouting hole, 5-embedded strip, 6-embedded groove, 7-frame steel bar, 8-reinforcement steel bar. DETAILED DESCRIPTION

[0029] To make the purpose, technical solution and advantages of the embodiments of the present invention more clear, the technical solution in the embodiments of the present invention will be clearly and completely described below in conjunction with the accompanying drawings in the embodiments of the present invention.

[0030] It should be noted that similar symbols and letters denote similar items in the following drawings, and therefore, once an item is defined in one drawing, it does not require further definition and explanation in the subsequent drawings.

[0031] In the description of the present invention, it should be noted that the terms "upper", "lower", "left", "right", "inner", "outer", "front", "back" and the like indicate positions or positional relationships based on the positions or positional relationships shown in the drawings, or are the positions or positional relationships in which the inventive product is usually placed when in use, and are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on the present invention. A coordinate system XYZ is provided in the drawings of the embodiments of the present invention, wherein the positive direction of the X-axis represents the front, the reverse direction of the X-axis represents the back, the positive direction of the Y-axis represents the right, the reverse direction of the Y-axis represents the left, the positive direction of the Z-axis represents the top, and the reverse direction of the Z-axis represents the bottom.

[0032] It should be understood that the terms described in the present invention are only embodiments for describing features and are not intended to limit the present invention. In addition, for the numerical range in the present invention, it should be understood that each intermediate value between the upper and lower limits of the scope is also specifically disclosed. Each smaller range between the intermediate value in any stated value or stated range and any other stated value or intermediate value in the described range is also included in the present invention. The upper and lower limits of these smaller ranges can be independently included or excluded in the scope.

[0033] It will be apparent to those skilled in the art that various modifications and variations may be made to the specific embodiments of the present invention description without departing from the scope or spirit of the present invention. Other embodiments derived from the present invention description will be apparent to those skilled in the art. The present application description and examples are exemplary only.

[0034] Combination Figure 1 and Figure 2 As shown, an embodiment of the present invention provides an ultra-high performance concrete segment, which is the main assembly component of shield construction. Multiple concrete segments are assembled together as the innermost barrier of the tunnel, and bear the role of resisting soil layer pressure, groundwater pressure and some special loads. The ultra-high performance concrete segment includes a segment body 1, at least two bolt holes 2 are arranged around the segment body 1, and a plurality of bolt slots 3 are arranged at the bottom of the segment body 1. The bolt holes 2 correspond to the bolt slots 3 one by one, and the two ends of the bolt holes 2 extend to the side wall of the segment body 1 and the slot wall of the bolt slot 3. In this embodiment, the front (positive direction of the X axis in the figure) and the rear (negative direction of the X axis in the figure) parts of the segment body 1 are each provided with three bolt holes 2, the left (positive direction of the Y axis in the figure) and the right (negative direction of the Y axis in the figure) parts are each provided with two bolt holes 2, and the bottom of the segment is provided with a total of 8 bolt slots 3, two are arranged on the left and right sides, and three are arranged on the front and rear sides. Adjacent segments are connected by bolts passing through bolt holes 2. The segment body 1 is in the shape of an arc plate. Multiple segments are spliced ​​in the left-right direction to form a ring structure. Adjacent segments of the ring are connected in the front-back direction to form a pipe structure. A grouting hole 4 is provided in the middle of the segment body 1 for secondary grouting later.

[0035] Furthermore, a raised fillet 5 is provided on the front side wall of the segment body 1, and a recessed embedding groove 6 is provided on the rear side wall of the segment body 1. The fillet 5 matches the embedding groove 6 in shape and is used to connect segments of adjacent rings. The segments of adjacent rings are connected by embedded matching bolts, which makes the connection more reliable, increases the construction efficiency, and simplifies the alignment procedure during the construction of the shield machine. In addition, the matching structure of the fillet 5 and the embedding groove 6 strengthens the connection reliability of the adjacent ring connection, and can also effectively prevent defects in the connection and avoid water seepage from the connection.

[0036] The material of the segment body 1 is ultra-high performance concrete, which has the characteristics of strong compression, tension, flexural resistance and high toughness, and enhances the segment's ability to resist soil pressure and water pressure. The segment body 1 is made of the following raw materials: cement 750-840kg / m 3 , active silicon powder 80-110kg / m 3 , fly ash microbeads 120-210kg / m 3 , crushed stone 0-200kg / m 3 , sand 960-1160kg / m 3 , steel fiber 60-100kg / m 3 , plastic fiber 0-5kg / m 3 , water 190-240kg / m 3 , water reducing agent 15-40kg / m 3 , expansion agent 0-20kg / m 3 Ultra-high performance concrete has a dense structure and is not easy to be damaged. During the construction process, it is not easy for edges, corners and surfaces to be damaged. Harmful elements are not easy to enter the interior of the pipe segment, which enhances the durability of ultra-high performance concrete materials, reduces the cost of later maintenance and overhaul, and increases the overall life of the pipe segment project.

[0037] In a specific embodiment of the present invention, the specific surface area of ​​the active silicon powder is greater than or equal to 10000m 2 / kg, the particle size of fly ash microbeads is greater than or equal to 170 meshes, and the micro-aggregate effect of fly ash microbeads and active silica powder makes the ultra-high performance concrete structure more reasonable. The fiber material is a compound of steel fiber and plastic fiber. The addition of fiber material greatly improves the compression, bending and cracking resistance of ultra-high performance concrete. The plastic fiber is selected from one or more of polypropylene fiber, polyvinyl alcohol fiber, and polyethylene plastic steel fiber. The water reducer is a polycarboxylic acid water reducer with a water reduction rate greater than or equal to 40%. The water reducer greatly reduces the water-cement ratio of the concrete system and improves the compressive strength of ultra-high performance concrete. The expansion agent is a compound expansion agent of MEA expansion agent and CSA expansion agent. The activity index of MEA expansion agent is less than or equal to 120s, and the CaO content in CSA expansion agent is greater than or equal to 55%. The addition of expansion agent avoids early shrinkage cracking of ultra-high performance concrete.

[0038] Compared with ordinary concrete, the ultra-high performance concrete prepared from the above raw material components has ultra-high compressive strength and axial tensile strength. Ultra-high compressive strength is the basis of all mechanical properties. Ultra-high axial tensile strength increases the bending resistance of the segment, so the thickness of the segment can be reduced, meeting the construction requirements of the segment while reducing the use of concrete raw materials; good toughness and impermeability indicate that the segment has extremely high durability; the good expansion and fluidity of ultra-high performance concrete are suitable for the pumping and laying of the segment, improving production efficiency; and the structure of the ultra-high performance concrete segment is denser than that of ordinary concrete, which inhibits harmful components from entering the interior of the ultra-high performance concrete, improving the durability of the ultra-high performance concrete material, and the dense structure and ultra-high strength of the ultra-high performance concrete also avoid damage during transportation. After the segment is installed, it has excellent waterproof performance, eliminating phenomena such as water seepage.

[0039] Combination Figures 3 to 5 As shown, compared with ordinary concrete segments, the ultra-high performance concrete segment can support the skeleton of the segment only by the ultra-high performance concrete material itself, which can greatly reduce the steel bars in the segment body 1. The segment body 1 is provided with a steel bar assembly, which consists of a frame steel bar 7 and a reinforcing steel bar 8. The dotted line in the figure represents the frame steel bar 7, and the dotted line represents the reinforcing steel bar 8. The frame steel bar 7 is arranged along the edge of the segment body 1 to form a shape support structure of the segment body 1. The reinforcing steel bar 8 is arranged around the bolt hole 2 and the bolt groove 3 to strengthen the structure of the ultra-high performance concrete thinning parts such as the bolt hole 2 and the bolt groove 3. In this embodiment, there are 12 frame steel bars 7 and 30 reinforcing steel bars 8 in the segment body 1. Some of the reinforcing steel bars 8 run through the extension direction of the segment body 1, and can be reinforced by multiple bolt holes 2 or bolt grooves 3. Each bolt hole 2 or bolt groove 3 has at least 4 corresponding reinforcing steel bars 8, and the distance between the reinforcing steel bar 8 and the corresponding bolt hole 2 or bolt groove 3 is less than or equal to 20 mm. The ultra-high performance concrete segment significantly reduces the steel bars in the segment body 1. Only the frame steel bars 7 of the outermost layer and the reinforcing steel bars 8 around the bolt holes 2 and bolt grooves 3 are required. Compared with traditional segment materials, the amount of concrete material is reduced by half and the amount of steel is reduced by 80%, which saves on the use of raw materials, reduces the dead weight of the segment, and facilitates the lifting, transportation and construction of the segment.

[0040] Ultra-high performance concrete material has excellent compression and bending resistance, so that the thickness of ultra-high performance concrete segments can be designed to be smaller than that of ordinary segments. In a specific embodiment of the present invention, the thickness of the segment body 1 is 100mm-150mm, which greatly reduces the use of raw materials such as cement and facilitates on-site construction.

[0041] The material of the tube segment body 1 provided by the present invention is described in detail below in conjunction with specific embodiments.

[0042] Example 1

[0043] The material of the segment body is composed of the following raw materials: cement 840kg / m 3 , active silica powder 110kg / m 3 , fly ash microbeads 120kg / m 3 , sand 1160kg / m 3 , steel fiber 76.3kg / m 3 , water 235.4kg / m 3 , water reducing agent 16.05kg / m 3 .

[0044] In this embodiment, the amount of adhesive in each cubic meter of ultra-high performance concrete system is 1070 kg / m 3 , the water-reducing agent dosage is 0.015%, the water-cement ratio is 0.22, and the volume dosage of steel fiber is 1%. The ultra-high performance concrete can be completely dispersed, with an expansion of 764mm, excellent fluidity, and is suitable for pumping. After the ultra-high performance concrete test block is formed, it is placed in a steam curing tank with a temperature of 85°C and a humidity of 98% for curing for 6 hours. The demoulding compressive strength of the test piece is 122MPa, and the axial tensile strength is 4.4MPa. The compressive strength after 28d is 137MPa, and the axial tensile strength is 5.0MPa. The anti-seepage effect of the ultra-high performance concrete in this embodiment is general, and there are no obvious macro cracks on the surface of the ultra-high performance concrete test block.

[0045] The ultra-high performance concrete of this embodiment has good performance. During the on-site experiment, the processes of pumping, pouring, and vibrating were smooth, and it is suitable for the production and manufacturing of pipe segments.

[0046] Example 2

[0047] The material of the segment body is composed of the following raw materials: cement 840kg / m 3 , active silica powder 110kg / m 3 , fly ash microbeads 120kg / m 3 , crushed stone 0-200kg / m 3 , sand 960kg / m 3 , steel fiber 76.3kg / m 3 , water 235.4kg / m 3 , water reducing agent 16.05kg / m 3 .

[0048] In this embodiment, the amount of adhesive in each cubic meter of ultra-high performance concrete system is 1070 kg / m 3Compared with Example 1, the total amount of aggregate remains unchanged, but 200kg of crushed stone with a particle size of 5-10mm is added, the amount of water reducer is 0.015%, the water-cement ratio is 0.22, and the volume content of steel fiber is 1%. The ultra-high performance concrete can be completely dispersed, with an expansion of 671mm, good fluidity, and is suitable for pumping. After the ultra-high performance concrete test block is formed, it is placed in a steam curing tank with a temperature of 85°C and a humidity of 98% for curing for 6 hours. The demoulding compression resistance of the test piece is 117MPa, the axial tensile strength is 3.9MPa, the compressive strength after 28d is 126MPa, and the axial tensile strength is 4.5MPa. The anti-seepage effect of the ultra-high performance concrete in this embodiment is general, and there are no obvious macro cracks on the surface of the ultra-high performance concrete test block.

[0049] The ultra-high performance concrete of this embodiment has good performance. During the on-site experiment, the processes of pumping, pouring, and vibrating were smooth, and it is suitable for the production and manufacturing of pipe segments.

[0050] Example 3

[0051] The material of the segment body is composed of the following raw materials: cement 750kg / m 3 , active silicon powder 80kg / m 3 , fly ash microbeads 210kg / m 3 , sand 1160kg / m 3 , steel fiber 76.3kg / m 3 , plastic fiber 1.3kg / m 3 , water 203.3kg / m 3 , water reducing agent 26.75kg / m 3 , expansion agent 15.3kg / m 3 .

[0052] In this embodiment, the amount of adhesive in each cubic meter of ultra-high performance concrete system is 1040 kg / m 3 , the water-reducing agent dosage is 0.025%, the water-cement ratio is 0.18, the volume dosage of steel fiber is 1%, 1.3kg of polypropylene fiber is added to each cubic meter of concrete, and 15.3kg of MEA-CSA composite expansion agent is added to each cubic meter of concrete. The ultra-high performance concrete can be completely dispersed, with an expansion degree of 530mm, good fluidity, and can be pumped. After the concrete test block is formed, it is placed in a steam curing tank with a temperature of 85°C and a humidity of 98% for curing for 6 hours. The demoulding compressive strength of the test piece is 140MPa, and the axial tensile strength is 6.6MPa. The compressive strength after 28d is 153MPa, and the axial tensile strength is 6.7Mpa. The added polypropylene fiber improves the axial tensile strength of the test block. The ultra-high performance concrete of this embodiment has excellent anti-seepage effect, and there are no obvious macro cracks on the surface of the ultra-high performance concrete test block.

[0053] The ultra-high performance concrete of this embodiment has good performance. During the on-site experiment, the pumping, pouring, and vibration processes were smooth. There were no macro cracks on the surface of the segment. It has good long-term stability and excellent durability, and is suitable for segment production.

[0054] Example 4

[0055] The material of the segment body is composed of the following raw materials: cement 840kg / m 3 , active silica powder 110kg / m 3 , fly ash microbeads 120kg / m 3 , sand 1160kg / m 3 , steel fiber 76.3kg / m 3 , water 192.6kg / m 3 , water reducing agent 26.75kg / m 3 .

[0056] The amount of adhesive in each cubic meter of ultra-high performance concrete system in this embodiment is 1070 kg / m 3 , the water-reducing agent dosage is 0.025%, the water-cement ratio is 0.18, and the volume dosage of steel fiber is 1%. Whether the ultra-high performance concrete can be completely dispersed, the expansion is 464mm, the fluidity is general, and it is not suitable for pumping. After the concrete test block is formed, it is placed in a steam curing tank with a temperature of 85°C and a humidity of 98% for curing for 6 hours. The demoulding compressive strength of the test piece is 136MPa, the axial tensile strength is 5.1MPa, and the compressive strength after 28d is 144MPa, and the axial tensile strength is 5.5MPa. The ultra-high performance concrete has average impermeability, and there are obvious macro cracks on the surface of the ultra-high performance concrete test block.

[0057] The ultra-high performance concrete of this embodiment has good performance, and the processes of pumping, pouring, and vibrating are relatively smooth during the on-site experiment, but its durability is poor.

[0058] Example 5

[0059] The material of the segment body is composed of the following raw materials: cement 840kg / m 3 , active silicon powder 60kg / m 3 , fly ash microbeads 190kg / m 3 , sand 1160kg / m 3 , steel fiber 76.3kg / m 3 , water 199.8kg / m 3 , water reducing agent 27.75kg / m 3 .

[0060] The amount of adhesive in each cubic meter of ultra-high performance concrete system in this embodiment is 1110 kg / m 3, the water-reducing agent dosage is 0.025%, the water-cement ratio is 0.18, and the volume dosage of steel fiber is 1%. The ultra-high performance concrete can be completely dispersed, with an expansion of 537mm, good fluidity, and can be pumped. After the concrete test block is formed, it is placed in a steam curing tank with a temperature of 85°C and a humidity of 98% for curing for 6 hours. The demoulding compressive strength of the test piece is 142MPa, the axial tensile strength is 5.0MPa, and the compressive strength after 28d is 149MPa, and the axial tensile strength is 5.2MPa. The ultra-high performance concrete has average impermeability, and there are obvious macro cracks on the surface of the ultra-high performance concrete test block.

[0061] The ultra-high performance concrete of this embodiment has good performance. During the on-site experiment, the processes of pumping, pouring, and vibrating were relatively smooth, but there were a few macro cracks on the surface of the pipe segment.

[0062] Example 6

[0063] The material of the segment body is composed of the following raw materials: cement 750kg / m 3 , active silicon powder 80kg / m 3 , fly ash microbeads 210kg / m 3 , sand 1160kg / m 3 , steel fiber 76.3kg / m 3 , plastic fiber 1.3kg / m 3 Water 203.3kg / m 3 , water reducing agent 26.75kg / m 3 .

[0064] The amount of adhesive in each cubic meter of ultra-high performance concrete system in this embodiment is 1040 kg / m 3 , the water-reducing agent dosage is 0.025%, the water-cement ratio is 0.18, the volume dosage of steel fiber is 1%, and 1.3kg of polypropylene fiber is added to each cubic meter of concrete. Ultra-high performance concrete can be completely dispersed, with an expansion of 551mm, good fluidity, and can be pumped. After the concrete specimens are formed, they are placed in a steam curing tank at a temperature of 85°C and a humidity of 98% for curing for 6 hours. The demoulding compressive strength of the specimens is 144MPa, and the axial tensile strength is 6.7MPa. After 28d, the compressive strength is 156MPa, and the axial tensile strength is 6.9MPa. Ultra-high performance concrete has excellent anti-seepage effect, and there are no obvious macro cracks on the surface of the ultra-high performance concrete specimens.

[0065] The ultra-high performance concrete of this embodiment has good performance. During the on-site experiment, the processes of pumping, pouring, and vibrating were relatively smooth, but there were a few macro cracks on the surface of the pipe segment.

[0066] Although the disclosure of the present invention is as above, the protection scope of the present invention is not limited thereto. Those skilled in the art should know that various changes and modifications can be made without departing from the disclosure scope of the present invention, and these changes and modifications will fall within the protection scope of the present invention.

Claims

1. An ultra-high performance concrete segment, characterized in that: The invention comprises a segment body (1), wherein the segment body (1) is made of ultra-high performance concrete, at least two bolt holes (2) are arranged around the segment body (1), a plurality of bolt grooves (3) are arranged at the bottom of the segment body (1), the bolt holes (2) correspond to the bolt grooves (3) one by one, the two ends of the bolt holes (2) extend to the side wall of the segment body (1) and the groove wall of the bolt groove (3), a steel bar assembly is arranged in the segment body (1), the steel bar assembly consists of a frame steel bar (7) and a reinforcing steel bar (8), the frame steel bar (7) is arranged along the edge of the segment body (1), and the reinforcing steel bar (8) is arranged around the bolt holes (2) and the bolt groove (3); The material of the segment body (1) is composed of the following raw materials: cement 750-840 kg / m 3 , active silicon powder 80-110kg / m 3 , fly ash microbeads 120-210kg / m 3 , crushed stone 0-200kg / m 3 , sand 960-1160kg / m 3 , steel fiber 60-100kg / m 3 , plastic fiber 0-5kg / m 3 , water 190-240kg / m 3 , water reducing agent 15-40kg / m 3 , expansion agent 0-20kg / m 3 The expansion agent is a compound expansion agent of MEA expansion agent and CSA expansion agent, the activity index of the MEA expansion agent is less than or equal to 120s, the CaO content in the CSA expansion agent is greater than or equal to 55%, and the specific surface area of ​​the active silicon powder is greater than or equal to 10000m 2 / kg, the particle size of the fly ash microbeads is greater than or equal to 170 meshes, and the particle size of the crushed stone is less than or equal to 10mm.

2. The ultra-high performance concrete segment according to claim 1, characterized in that: The plastic fiber is selected from one or more of polypropylene fiber, polyvinyl alcohol fiber, and polyethylene plastic-steel fiber.

3. The ultra-high performance concrete segment according to claim 1, characterized in that: The water reducing agent is a polycarboxylic acid water reducing agent, and the water reducing rate is greater than or equal to 40%.

4. The ultra-high performance concrete segment according to any one of claims 1 to 3, characterized in that: The thickness of the segment body (1) is 100 mm-150 mm.

5. The ultra-high performance concrete segment according to any one of claims 1 to 3, characterized in that: A convex fillet (5) is provided on the front side wall of the tube segment body (1), and a concave fillet groove (6) is provided on the rear side wall of the tube segment body (1), and the fillet (5) matches the shape of the fillet groove (6).

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