Fabricated UHPC independent foundation and forming method and bearing capacity calculation method thereof

Abstract

The invention discloses a fabricated UHPC independent foundation and a forming method and a bearing capacity calculation method thereof. The independent foundation comprises a bottom formwork, a base formwork and a foundation module which are sequentially and coaxially stacked. The bottom formwork comprises a first bottom plate module and a second bottom plate module which are oppositely spliced, rectangular notches are formed in the opposite sides of the first bottom plate module and the second bottom plate module and form a post-cast strip area, first U-shaped steel bars and second U-shaped steel bars are arranged in the rectangular notches, and first rectangular protruding blocks, second rectangular protruding blocks, first steel bar tenons and second steel bar tenons are arranged on the top faces of the first bottom plate module and the second bottom plate module. Through grooves matched with the first rectangular protruding block and the second rectangular protruding block and grouting through holes in one-to-one correspondence with the first rebar tenon and the second rebar tenon are formed in the upper bottom face of the base formwork. The force conduction path of the connection structure is defined through the structural design of the foundation, the overall strength of the foundation is guaranteed while the joint structure is optimized, meanwhile, the strength of the bearing capacity of the joint area is further guaranteed according to the design of the post-cast strip area of the splicing part, and the weight of the foundation is effectively reduced.

Description

Technical Field

[0001] The invention relates to an independent foundation, belonging to the technical field of assembled structures, and in particular to an assembled UHPC independent foundation and a forming method and a bearing capacity calculation method thereof. Background Art

[0002] At present, the foundation of house buildings is generally constructed by cast-in-place method; however, according to engineering practice experience, cast-in-place foundation has several significant defects: first, its construction period is long, including foundation formwork, steel bar binding and foundation maintenance, which are time-consuming, thus greatly extending the overall structure construction period; second, the construction quality is difficult to be effectively guaranteed, especially for densely reinforced parts such as foundation short columns and pedestals, resulting in complex node structure. If a simple streamlined node structure is used, the strength of these parts will be reduced.

[0003] With the continuous progress of the construction industry, the research on prefabricated foundations has achieved some results. However, the current prefabricated foundations are mainly made of ordinary concrete, which leads to large volume and weight, which brings great inconvenience to transportation and installation. In addition, the ordinary concrete prefabricated foundation has poor durability and still needs further improvement. Therefore, a new method is urgently needed to solve the above problems existing in the prior art. Summary of the invention

[0004] The purpose of the present invention is to overcome the defects and problems of the prior art, such as complex structure and heavy weight, and to provide an assembled UHPC independent foundation with simple structure and light weight, as well as a forming method and a bearing capacity calculation method thereof.

[0005] To achieve the above objectives, the technical solution of the present invention is: an assembled UHPC independent foundation, comprising: a bottom template, a base template and a foundation module;

[0006] The bottom template is in the shape of a rectangular plate, and includes a first bottom plate module and a second bottom plate module; a first rectangular notch is opened on the side of the first bottom plate module, and a second rectangular notch is opened on the side opposite to the first bottom plate module;

[0007] After the first floor module and the second floor module are relatively spliced ​​and arranged, the first rectangular notch and the second rectangular notch are surrounded to form a post-casting zone area;

[0008] A plurality of first U-shaped steel bars are arranged in the first rectangular notch, and the plurality of first U-shaped steel bars are arranged in sequence and at intervals along the direction of the first rectangular notch;

[0009] A plurality of second U-shaped steel bars are arranged in the second rectangular notch, and the plurality of second U-shaped steel bars are arranged in sequence and at intervals along the direction of the second rectangular notch;

[0010] The top surface of the first bottom plate module is provided with a first rectangular protrusion and a plurality of first steel bar tenons; one side of the first rectangular protrusion is co-edge with the first rectangular notch; and the plurality of first steel bar tenons are arranged in parallel on the other side of the first rectangular protrusion;

[0011] The top surface of the second bottom plate module is provided with a second rectangular protrusion and a plurality of second steel bar tenons; one side of the second rectangular protrusion is co-edge with the second rectangular notch; and the plurality of second steel bar tenons are arranged in parallel on the other side of the second rectangular protrusion;

[0012] The base template is in the shape of a rectangular plate, and its side length is smaller than the bottom template; the base template is coaxially stacked and arranged on the bottom template; a plurality of grouting through holes are opened on the base template, and a through groove is opened on the bottom surface of the base template; the first rectangular protrusion and the second rectangular protrusion are both located in the through groove, and the setting positions of the plurality of grouting through holes correspond to the first steel bar tenon and the second steel bar tenon respectively;

[0013] The basic module is in the shape of a rectangular cylinder, and its side length is smaller than the base template; the basic module is coaxially stacked on the base template.

[0014] A first steel mesh is disposed horizontally and vertically inside the first floor module, and a second steel mesh is disposed horizontally and vertically inside the second floor module;

[0015] A third steel mesh is arranged horizontally and vertically in the interior of the base template, and a fourth steel mesh is arranged vertically and horizontally in the interior of the basic module.

[0016] The bottom end of the first steel bar tenon vertically extends into the first steel bar mesh for fixed connection; the bottom end of the second steel bar tenon vertically extends into the second steel bar mesh for fixed connection;

[0017] The bottom end of the fourth steel mesh vertically extends into the third steel mesh and is fixedly connected thereto.

[0018] One end of the first U-shaped steel bar horizontally extends into the first rectangular protrusion for fixed connection, and the other end horizontally extends into the first steel mesh for fixed connection;

[0019] One end of the second U-shaped steel bar horizontally extends into the second rectangular protrusion and is fixedly connected thereto, and the other end horizontally extends into the second steel mesh and is fixedly connected thereto.

[0020] The first steel bar tenon includes a plurality of I-shaped steel bars and a plurality of annular stirrups; the plurality of I-shaped steel bars are coaxially cross-arranged, and the plurality of annular stirrups are coaxially spaced and sleeved on the periphery of the plurality of I-shaped steel bars; the structure of the second steel bar tenon is consistent with that of the first steel bar tenon.

[0021] The bottom of the opposite sides of the basic module are provided with triangular axil supports; the triangular axil supports are arranged parallel to the length direction of the post-casting zone area;

[0022] The side surface of the triangular axil support is fixedly connected to the basic module, and the bottom surface of the triangular axil support is fixedly connected to the top surface of the base template.

[0023] The grouting through hole is in the shape of a cylinder with a large diameter in the middle portion transitioning to small diameters at both ends.

[0024] The side wall of the grouting through hole is serrated.

[0025] A method for forming an assembled UHPC independent foundation, comprising:

[0026] S1, prefabricate the first base plate module, the second base plate module, the base template, and the basic module;

[0027] S2, splicing the first floor module and the second floor module in a mirror-symmetrical manner, so that the first rectangular notch and the second rectangular notch are enclosed to form a post-casting zone, and the first U-shaped steel bar and the second U-shaped steel bar are interlaced with each other;

[0028] S3, inserting steel bars into the interlaced area of ​​the first U-shaped steel bars and the second U-shaped steel bars and tying them up for fixing;

[0029] S4, hoisting the base template together with the basic module onto the bottom template, so that the through groove is engaged with the first rectangular protrusion and the second rectangular protrusion, and the plurality of first steel bar tenons and the plurality of second steel bar tenons are located one by one in the plurality of grouting through holes;

[0030] S5. Pour concrete in the post-casting zone and dry and cure for 10-18 days;

[0031] S6. Pour concrete into several grouting holes and dry-cure for 10-18 days to obtain an assembled UHPC independent foundation.

[0032] A method for calculating the bearing capacity of an assembled UHPC independent foundation, comprising:

[0033] The cross section of the post-casting zone is taken as the most unfavorable cross section, and the net reaction force of the base of the post-casting zone is calculated; the calculation formula is as follows:

[0034]

[0035] Where: p jx is the foundation pressure value at a distance x from the post-cast zone, p jmax is the maximum net foundation reaction design value at the bottom edge, p j is the net reaction force of the bottom foundation in the post-cast zone area;

[0036] Will Substitute it into the integral formula and simplify it to calculate the bending moment in the post-cast zone under the eccentric compressive load; the integral formula is as follows:

[0037]

[0038] Where: M P is the bending moment in the post-cast zone under eccentric compressive load, p max is the maximum foundation reaction design value at the bottom edge corresponding to the basic combination of actions, G is the self-weight and the self-weight of the soil on it, p is the foundation reaction design value at the bottom of the post-casting zone area corresponding to the basic combination of actions, and A is the bottom area;

[0039] The most unfavorable section during reinforcement is taken as the post-casting zone area, and the reinforcement area of ​​the post-casting zone area is calculated based on the bending moment of the post-casting zone area; the calculation formula is as follows:

[0040]

[0041] Among them: A s is the reinforcement area of ​​the post-cast zone, f y is the design value of steel bar tensile strength, h0 is the thickness of post-casting zone, and 1.2 is the bending moment magnification factor;

[0042] The ultimate pull-out bearing capacity of the steel bar tenon overlap area with interface compressive stress is calculated; the calculation formula of the ultimate pull-out bearing capacity is as follows:

[0043]

[0044] C1=0.878f cc 0.4 ;

[0045] C2=0.167f cc 0.3 ;

[0046] Where: A is the interface contact area, μ is the friction coefficient, σ n is the average compressive stress at the interface, C1 and C2 are coefficients, ρ is the shear interface reinforcement ratio, and f cc is the compressive strength of concrete.

[0047] Compared with the prior art, the present invention has the following beneficial effects:

[0048] 1. In the present invention, an assembled UHPC independent foundation and its forming method and bearing capacity calculation method, the independent foundation includes a bottom template, a base template and a foundation module coaxially stacked in sequence; the bottom template includes a first and a second bottom plate module spliced ​​relatively, and the opposite sides thereof are provided with rectangular notches, and formed into a post-casting zone, and the first and the second U-shaped steel bars are provided in the rectangular notches, and the top surfaces of the first and the second bottom plate modules are provided with first and second rectangular protrusions and first and second steel bar tenons; the bottom surface of the base template is provided with a through groove matching the first and the second rectangular protrusions, and a grouting through hole corresponding to the first and the second steel bar tenons; in the application of this design, the force conduction path of the connection structure is clarified through the structural design of the foundation, and the design of the connection nodes of the grooves, protrusions and steel bar tenons optimizes the node structure while ensuring the overall strength of the foundation, and at the same time, the post-casting zone area design of the spliced ​​part further ensures the strength of the bearing capacity of the node area, and effectively reduces the weight of the foundation. Therefore, the structure of the present invention is simple and light.

[0049] 2. In the assembled UHPC independent foundation and its forming method and bearing capacity calculation method of the present invention, the connection node structure is simplified without sacrificing the structural strength, which is convenient for on-site installation and design. In addition, the high-strength and high-performance concrete UHPC is used to reduce the weight of the foundation, thereby facilitating transportation and installation. BRIEF DESCRIPTION OF THE DRAWINGS

[0050] Figure 1 It is a structural schematic diagram of the independent basis of the present invention.

[0051] Figure 2 It is a structural schematic diagram of the first and second baseboard modules in the present invention.

[0052] Figure 3 It is a structural schematic diagram of the post-casting zone area in the present invention.

[0053] Figure 4 It is a structural schematic diagram of the first steel mesh in the present invention.

[0054] Figure 5 It is a schematic structural diagram of the second steel mesh in the present invention.

[0055] Figure 6 It is a schematic structural diagram of the third and fourth steel meshes in the present invention.

[0056] Figure 7 It is a structural schematic diagram of the through groove and the grouting through hole in the present invention.

[0057] Figure 8 yes Figure 7 Bottom view of .

[0058] Fig. 9It is a structural schematic diagram of the grouting through hole in the present invention.

[0059] Fig.10 It is a structural schematic diagram of the first and second steel bar tenons in the present invention.

[0060] In the figure: bottom formwork 1, first bottom plate module 11, second bottom plate module 12, first rectangular notch 13, second rectangular notch 131, post-casting zone 132, first U-shaped steel bar 14, second U-shaped steel bar 141, first rectangular protrusion 15, second rectangular protrusion 151, first steel bar tenon 16, second steel bar tenon 161, I-shaped steel bar 162, annular stirrups 163, first steel mesh 17, second steel mesh 171, third steel mesh 18, fourth steel mesh 19, base formwork 2, grouting through hole 21, through groove 22, foundation module 3, triangular axil support 31. DETAILED DESCRIPTION

[0061] The present invention is further described in detail below in conjunction with the accompanying drawings and specific implementation methods.

[0062] Embodiment 1:

[0063] See also Figure 1-Figure 9 , an assembled UHPC independent foundation, comprising: a bottom template 1, a base template 2 and a foundation module 3;

[0064] The bottom template 1 is in the shape of a rectangular plate, and includes a first bottom plate module 11 and a second bottom plate module 12; a first rectangular notch 13 is opened on the side of the first bottom plate module 11, and a second rectangular notch 131 is opened on the side opposite to the first bottom plate module 11 of the second bottom plate module 12;

[0065] After the first floor module 11 and the second floor module 12 are relatively spliced ​​and arranged, the first rectangular notch 13 and the second rectangular notch 131 are surrounded to form a post-casting zone area 132;

[0066] A plurality of first U-shaped steel bars 14 are disposed in the first rectangular notch 13, and the plurality of first U-shaped steel bars 14 are sequentially spaced apart along the direction of the first rectangular notch 13;

[0067] A plurality of second U-shaped steel bars 141 are disposed in the second rectangular notch 131 , and the plurality of second U-shaped steel bars 141 are sequentially spaced apart along the direction of the second rectangular notch 131 ;

[0068] The top surface of the first floor module 11 is provided with a first rectangular protrusion 15 and a plurality of first steel bar tenons 16; one side of the first rectangular protrusion 15 is co-edge with the first rectangular notch 13; and the plurality of first steel bar tenons 16 are arranged in parallel on the other side of the first rectangular protrusion 15;

[0069] The top surface of the second floor module 12 is provided with a second rectangular protrusion 151 and a plurality of second steel bar tenons 161; one side of the second rectangular protrusion 151 is co-edge with the second rectangular notch 131; and the plurality of second steel bar tenons 161 are arranged in parallel on the other side of the second rectangular protrusion 151;

[0070] The base template 2 is in the shape of a rectangular plate, and its side length is smaller than that of the bottom template 1; the base template 2 is coaxially stacked and arranged on the bottom template 1; a plurality of grouting through holes 21 are opened on the base template 2, and a through groove 22 is opened on the bottom surface of the base template 2; the first rectangular protrusion 15 and the second rectangular protrusion 151 are both located in the through groove 22, and the setting positions of the plurality of grouting through holes 21 correspond to the first steel bar tenon 16 and the second steel bar tenon 161 respectively;

[0071] The basic module 3 is in the shape of a rectangular cylinder, and its side length is smaller than the base template 2 ; the basic module 3 is coaxially stacked on the base template 2 .

[0072] Preferably, a first steel mesh 17 is disposed horizontally and vertically inside the first floor module 11, and a second steel mesh 171 is disposed horizontally and vertically inside the second floor module 12;

[0073] A third steel mesh 18 is horizontally and vertically arranged inside the base template 2, and a fourth steel mesh 19 is vertically and vertically arranged inside the basic module 3.

[0074] Preferably, the bottom end of the first steel bar tenon 16 vertically extends to the first steel bar mesh 17 for fixed connection; the bottom end of the second steel bar tenon 161 vertically extends to the second steel bar mesh 171 for fixed connection; the bottom end of the fourth steel bar mesh 19 vertically extends to the third steel bar mesh 18 for fixed connection.

[0075] Preferably, one end of the first U-shaped steel bar 14 extends horizontally to the first rectangular protrusion 15 for fixed connection, and the other end extends horizontally to the first steel mesh 17 for fixed connection; one end of the second U-shaped steel bar 141 extends horizontally to the second rectangular protrusion 151 for fixed connection, and the other end extends horizontally to the second steel mesh 171 for fixed connection.

[0076] Preferably, the first steel bar tenon 16 includes a plurality of I-shaped steel bars 162 and a plurality of annular stirrups 163; the plurality of I-shaped steel bars 162 are coaxially cross-arranged, and the plurality of annular stirrups 163 are coaxially spaced and sleeved on the periphery of the plurality of I-shaped steel bars 162; the structure of the second steel bar tenon 161 is consistent with the structure of the first steel bar tenon 16.

[0077] Preferably, triangular axil supports 31 are provided at the bottom of the relative sides of the basic module 3; the triangular axil supports 31 are arranged parallel to the length direction of the post-casting zone area 132; the side surfaces of the triangular axil supports 31 are fixedly connected to the basic module 3, and the bottom surfaces of the triangular axil supports 31 are fixedly connected to the top surface of the base formwork 2.

[0078] Preferably, the shape of the grouting through hole 21 is a transition from a large diameter in the middle to small diameters at both ends, and the side wall of the grouting through hole 21 is serrated.

[0079] In application, the first floor module 11 and the second floor module 12 are mirror-jointed, the first rectangular notch 13 and the second rectangular notch 131 are combined to form a post-cast zone 132, the first U-shaped steel bar 14 and the second U-shaped steel bar 141 extend toward each other and overlap alternately, and the overlap length is preferably 100-150 mm.

[0080] The thickness of the first rectangular protrusion 15 and the second rectangular protrusion 151 is preferably 100 mm, and the height of the corresponding through groove 22 is consistent therewith, and the contact area between the bottom template 1 and the base template 2 is increased through the contact between the protrusion and the groove.

[0081] The shape and the serrated cross section of the grouting through hole 21 can effectively ensure the adhesion of the area after grouting and ensure that the pull-out resistance meets the requirements.

[0082] The thickness of the triangular axil support 31 is preferably 1.4Δh. The triangular axil support 31 is arranged in the direction where the bending moment is larger and parallel to the post-cast zone area 132 to avoid local collapse of the prefabricated foundation.

[0083] The bottom ends of the first steel bar tenon 16 and the second steel bar tenon 161 are both bent in an L shape, which extend to the first steel bar mesh 17 and the second steel bar mesh 171 and are tied and fixed; the bottom end of the fourth steel bar mesh 19 is also bent in an L shape, which extends to the third steel bar mesh 18 and is tied and fixed, so as to ensure the connection strength after pouring.

[0084] Embodiment 2:

[0085] A method for forming an assembled UHPC independent foundation connection structure, comprising:

[0086] S1, the first base plate module 11, the second base plate module 12, the base formwork 2, and the basic module 3 are prefabricated;

[0087] S2, splicing the first floor module 11 and the second floor module 12 in a mirror-symmetrical manner, so that the first rectangular notch 13 and the second rectangular notch 131 are surrounded to form a post-casting zone area 132, and the first U-shaped steel bar 14 and the second U-shaped steel bar 141 are interlaced with each other;

[0088] S3, insert the steel bars into the interlaced area of ​​the first U-shaped steel bars 14 and the second U-shaped steel bars 141 and tie them up and fix them;

[0089] S4, hoisting the base template 2 together with the basic module 3 onto the bottom template 1, so that the through groove 22 is engaged with the first rectangular protrusion 15 and the second rectangular protrusion 151, and the plurality of first steel bar tenons 16 and the plurality of second steel bar tenons 161 are located one by one in the plurality of grouting through holes 21;

[0090] S5, pouring concrete in the post-cast zone area 132, and drying and curing for 10-18 days (preferably 14 days);

[0091] S6. Pour concrete into the plurality of grouting holes 21 and dry and cure for 10-18 days (preferably 14 days) to obtain an assembled UHPC independent foundation.

[0092] In application, the first base plate module 11, the second base plate module 12, the base formwork 2, and the basic module 3 are prefabricated on site or in a factory. During prefabrication, the steel bars are pre-buried and poured with concrete according to the calculated parameters such as reinforcement, size, thickness, concrete grade, etc., to form independent prefabricated parts; and the base formwork 2 and the steel mesh of the basic module 3 can be connected and fixed in advance and poured as a whole, and then connected to the bottom formwork 1 after forming a whole; concrete or other bonding media can also be appropriately applied to the contact surface of the through groove and the protrusion to enhance the bonding force.

[0093] Embodiment 3:

[0094] After the structure of the prefabricated UHPC independent foundation is determined, its bearing capacity needs to be calculated to meet the strength requirements; the bearing capacity calculation method of the prefabricated UHPC independent foundation includes two parts. One is the bending bearing capacity of the foundation base plate splicing node, which is entirely borne by the bending of the post-casting zone 132 between the first base plate module 11 and the second base plate module 12, which can be met by adjusting the thickness of the first rectangular protrusion 15 and the second rectangular protrusion 151 and the reinforcement of the splicing area; the second is that in the pull-out state, the overall pull-out bearing capacity provided by the four steel bar tenons is calculated to be greater than the ultimate shear bearing capacity of the key tooth joint and the deadweight of the first base plate module 11 and the second base plate module 12.

[0095] A method for calculating the bearing capacity of an assembled UHPC independent foundation connection structure, comprising:

[0096] The side lengths of the foundation bottom are l and b, where b is the side length of the foundation bottom perpendicular to the post-casting zone. When the calculation section is taken to the section of the post-casting zone, the bending moment value of the foundation bottom plate is the largest, which is usually referred to as the most dangerous section. It is also the most unfavorable section selected when designing reinforcement. At this time, the distance from the section in the post-casting zone of the foundation bottom plate to the edge of the assembled UHPC independent foundation is

[0097] The cross section of the post-casting zone is taken as the most unfavorable cross section, and the net reaction force of the base of the post-casting zone is calculated; the calculation formula is as follows:

[0098]

[0099] Where: p jx is the foundation pressure value at a distance x from the post-cast zone, p jmax is the maximum net foundation reaction design value at the bottom edge, p j is the net reaction force of the bottom foundation in the post-cast zone area;

[0100] Will Substituting into the integral formula, the bending moment of the post-cast zone under the eccentric compressive load is calculated;

[0101] The integral formula is expressed as follows:

[0102]

[0103] Simplifying the above integral formula, the integral formula is as follows:

[0104]

[0105] Where: M P is the bending moment in the post-cast zone under eccentric compressive load, p max is the maximum foundation reaction design value at the bottom edge corresponding to the basic combination of actions, G is the self-weight and the self-weight of the soil on it, p is the foundation reaction design value at the bottom of the post-casting zone area corresponding to the basic combination of actions, and A is the bottom area;

[0106] Furthermore, the bending moment at the bottom of the prefabricated UHPC independent foundation, such as the section at the step change point, can be calculated according to the formula recommended by the relevant specifications.

[0107] The most unfavorable section when reinforcing the post-casting belt area is taken as the area, and the reinforcement area of ​​the post-casting belt area is calculated based on the bending moment of the post-casting belt area;

[0108] The most unfavorable section selected when designing reinforcement takes into account the difference between the post-cast zone and the cast-in-place foundation, and is more important for the calculated bending moment value M P Multiplying by the magnification factor 1.2, the calculation formula is as follows:

[0109]

[0110] Among them: A s is the reinforcement area of ​​the post-cast zone, f y is the design value of steel bar tensile strength, h0 is the thickness of post-casting zone, and 1.2 is the bending moment magnification factor;

[0111] Furthermore, the reinforcement of the foundation slab can be calculated according to the formula recommended by the relevant specifications for other sections such as the sections at the step change of the prefabricated UHPC independent foundation.

[0112] After the structural form of the prefabricated UHPC independent foundation is determined, the thickness of the protrusions, concrete strength and reinforcement parameters in the post-cast zone are designed according to the above-mentioned bearing capacity and reinforcement requirements to meet the engineering requirements. Finally, calculations are performed to verify whether its ultimate pull-out bearing capacity can meet the requirements of the specifications.

[0113] Under the action of the pull-out force F, the prefabricated UHPC independent foundation relies on the self-weight of the foundation module 3 and the ultimate pull-out bearing capacity of the steel bar tenon overlap to jointly resist the pull-out action. From the mechanical equilibrium relationship, it can be obtained that:

[0114] F=W+F c ;

[0115] Where: F is the ultimate pull-out resistance of the independent foundation, W is the deadweight of the foundation module, F c is the bonding strength at the tenon of the steel bar;

[0116] W = blhγ;

[0117] Where: b and l are the lengths of the two sides of the bottom surface of the independent foundation, h is the thickness of the independent foundation, and γ is the weight of the independent foundation;

[0118] There is a corresponding cross-sectional compressive stress in the steel bar tenon overlap area, and the calculation method is as follows:

[0119] The ultimate pull-out bearing capacity of the steel bar tenon overlap area with interface compressive stress is calculated; the calculation formula of the ultimate pull-out bearing capacity is as follows:

[0120]

[0121] C1=0.878f cc 0.4 ;

[0122] C2=0.167f cc 0.3 ;

[0123] Where: A is the interface contact area, μ is the friction coefficient, σ nis the average compressive stress at the interface, C1 and C2 are coefficients, ρ is the shear interface reinforcement ratio, and f cc is the compressive strength of concrete.

[0124] Although the embodiments of the present invention have been shown and described above, it should be understood that the above embodiments are exemplary and should not be construed as limitations on the present invention. A person skilled in the art may change, modify, replace and vary the above embodiments within the scope of the present invention.

Claims

1. An assembled UHPC independent foundation, characterized in that: include: Bottom template (1), base template (2) and basic module (3); The bottom template (1) comprises a first bottom plate module (11) and a second bottom plate module (12) which are spliced ​​together; a first rectangular notch (13) is provided on a side of the first bottom plate module (11); a plurality of first U-shaped steel bars (14) are arranged in the first rectangular notch (13); a second rectangular notch (131) is provided on a side opposite to the first bottom plate module (11); a plurality of second U-shaped steel bars (141) are arranged in the second rectangular notch (131); the first rectangular notch (13) and the second rectangular notch (131) are combined to form a post-casting zone area (132); a first rectangular protrusion (15) and a plurality of first steel bar tenons (16) are provided on the top surface of the first bottom plate module (11); and a second rectangular protrusion (151) and a plurality of second steel bar tenons (17) are provided on the top surface of the second bottom plate module (12); The base template (2) is provided with a plurality of grouting through holes (21), the plurality of grouting through holes (21) respectively corresponding to the first steel bar tenon (16) and the second steel bar tenon (17); the bottom surface of the base template (2) is provided with a through groove (22), the first rectangular protrusion (15) and the second rectangular protrusion (151) are both located in the through groove (22); The basic module (3) is stacked and arranged on the base template (2).

2. The assembled UHPC independent foundation according to claim 1, characterized in that: A first steel mesh (111) is disposed horizontally and vertically inside the first floor module (11), and a second steel mesh (112) is disposed horizontally and vertically inside the second floor module (12); A third steel mesh (113) is arranged horizontally and vertically inside the base template (2), and a fourth steel mesh (114) is arranged vertically and horizontally inside the basic module (3).

3. The assembled UHPC independent foundation according to claim 2, characterized in that: The bottom end of the first steel bar tenon (16) vertically extends into the first steel bar mesh (111) for fixed connection; the bottom end of the second steel bar tenon (17) vertically extends into the second steel bar mesh (112) for fixed connection; The bottom end of the fourth steel mesh (114) vertically extends into the third steel mesh (113) and is fixedly connected thereto.

4. The assembled UHPC independent foundation according to claim 2, characterized in that: One end of the first U-shaped steel bar (14) horizontally extends into the first rectangular protrusion (15) for fixed connection, and the other end horizontally extends into the first steel mesh (111) for fixed connection; One end of the second U-shaped steel bar (141) extends horizontally into the second rectangular protrusion (151) for fixed connection, and the other end extends horizontally into the second steel mesh (112) for fixed connection.

5. The assembled UHPC independent foundation according to claim 1, characterized in that: The first steel bar tenon (16) and the second steel bar tenon (17) both comprise a plurality of I-shaped steel bars (161) and a plurality of annular stirrups (162); the plurality of I-shaped steel bars (161) are coaxially arranged in a cross-shaped manner, and the plurality of annular stirrups (162) are coaxially arranged at intervals on the periphery of the plurality of I-shaped steel bars (161).

6. The assembled UHPC independent foundation according to claim 1, characterized in that: The bottoms of the opposite sides of the basic module (3) are provided with triangular axil supports (31); the triangular axil supports (31) are arranged parallel to the length direction of the post-casting zone area (132); The side surface of the triangular axil support (31) is fixedly connected to the basic module (3), and the bottom surface of the triangular axil support (31) is fixedly connected to the top surface of the base template (2).

7. The assembled UHPC independent foundation according to claim 1, characterized in that: The grouting through hole (21) is in the shape of a cylinder with a large diameter in the middle portion transitioning to small diameters at both ends.

8. The assembled UHPC independent foundation according to claim 7, characterized in that: The side wall of the grouting through hole (21) is serrated.

9. A method for forming an assembled UHPC independent foundation according to any one of claims 1 to 8, characterized in that: include: S1, prefabricate the first base plate module (11), the second base plate module (12), the base template (2), and the basic module (3); S2, splicing the first floor module (11) and the second floor module (12) in a mirror-symmetrical manner, so that the first rectangular notch (13) and the second rectangular notch (131) are enclosed to form the post-casting zone area (132), and the first U-shaped steel bar (14) and the second U-shaped steel bar (141) are interlaced with each other; S3, inserting steel bars into the interlaced area of ​​the first U-shaped steel bars (14) and the second U-shaped steel bars (141), and tying and fixing them; S4, hoisting the base template (2) together with the basic module (3) onto the bottom template (1), so that the through groove (22) is engaged with the first rectangular protrusion (15) and the second rectangular protrusion (151), and the plurality of the first steel bar tenons (16) and the plurality of the second steel bar tenons (17) are located one by one in the plurality of the grouting through holes (21); S5, pouring concrete in the post-casting zone area (132) and in the plurality of grouting through holes (21) to obtain an assembled UHPC independent foundation.

10. A method for calculating the bearing capacity of an assembled UHPC independent foundation according to any one of claims 1 to 8, characterized in that: include: The cross section of the post-casting zone is taken as the most unfavorable cross section, and the net reaction force of the base of the post-casting zone is calculated; the calculation formula is as follows: Where: p jx is the foundation pressure value at a distance x from the post-cast zone, p jmax is the maximum net foundation reaction design value at the bottom edge, p j is the net reaction force of the bottom foundation in the post-cast zone area; Will Substitute it into the integral formula and simplify it to calculate the bending moment in the post-cast zone under the eccentric compressive load; the integral formula is as follows: Where: M P is the bending moment in the post-cast zone under eccentric compressive load, p max is the maximum foundation reaction design value at the bottom edge corresponding to the basic combination of actions, G is the self-weight and the self-weight of the soil on it, p is the foundation reaction design value at the bottom of the post-casting zone area corresponding to the basic combination of actions, and A is the bottom area; The most unfavorable section during reinforcement is taken as the post-casting zone area, and the reinforcement area of ​​the post-casting zone area is calculated based on the bending moment of the post-casting zone area; the calculation formula is as follows: Among them: A s is the reinforcement area of ​​the post-cast zone, f y is the design value of steel bar tensile strength, h0 is the thickness of post-casting zone, and 1.2 is the bending moment magnification factor; The ultimate pull-out bearing capacity of the steel bar tenon overlap area with interface compressive stress is calculated; the calculation formula of the ultimate pull-out bearing capacity is as follows: C1=0.878f cc 0.4 ; C2=0.167f cc 0.3 ; Where: A is the interface contact area, μ is the friction coefficient, σ n is the average compressive stress at the interface, C1 and C2 are coefficients, ρ is the shear interface reinforcement ratio, and f cc is the compressive strength of concrete.

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