Building structure, building structure design method and building structure construction method

Abstract

The invention relates to the technical field of building engineering, in particular to a building structure, a building structure design method and a building structure construction method.The beam body of the building structure is internally provided with a first prestress line body and a second prestress line body; the first prestressed line body comprises a first sub-line segment, a second sub-line segment and a third sub-line segment which are sequentially connected in the length direction of the beam body; the first sub-line segment and the third sub-line segment are parabolas with downward openings, the second sub-line segment is a parabola with an upward opening, and the distance between the lowest point of the second sub-line segment and the bottom surface of the beam body, the distance between the highest point of the first sub-line segment and the top surface of the beam body and the distance between the highest point of the third sub-line segment and the top surface of the beam body are controlled; and the distance between the linear second prestress line body and the bottom surface of the beam body is controlled, so that the unbalanced bending moment generated by the end part of the beam and the end part of the column due to the combined action of a dead load and a live load is reduced.

Description

Technical Field

[0001] The present invention relates to the technical field of building engineering, and in particular to a building structure, a building structure design method and a building structure construction method. Background Art

[0002] With the vigorous development of industries such as sports, performing arts, and exhibitions, the demand for column-free and large-span interior spaces has become increasingly prominent, which has posed unprecedented challenges to the field of building structure design. In this context, prestressed concrete structures have become the key solution to this problem due to their advantages in construction convenience, safety, durability, and cost-effectiveness. In existing large-span prestressed cast-in-place concrete structures, the linear design of the prestressed wire body mostly adopts a parabola with a high rise-to-span ratio. After research, the inventors found that the setting method of the prestressed wire body, the parabola with a high rise-to-span ratio, will cause a large unbalanced bending moment at the end of the beam and the end of the column, which will have an adverse effect on the safety of the building structure. Summary of the Invention

[0003] The technical problem to be solved by the present invention is that in existing large-span prestressed cast-in-place concrete structures, the linear shape of the prestressed linear body mostly adopts a parabola with a high span-ratio, resulting in large unbalanced bending moments at the ends of beams and columns.

[0004] In order to solve the above technical problems, the present invention aims to provide a building structure, comprising a first column, a second column and a beam, wherein the first column and the second column are arranged in parallel and spaced apart, and the two ends of the beam are respectively arranged on the first column and the second column;

[0005] The beam body is provided with a first prestressed wire body and a second prestressed wire body; the first prestressed wire body includes a first sub-segment, a second sub-segment and a third sub-segment connected in sequence along the length direction of the beam body; the second sub-segment is a parabola with an opening facing upward, the first sub-segment and the third sub-segment are both parabolas with an opening facing downward, the distance between the lowest point of the second sub-segment and the bottom surface of the beam body is greater than or equal to one tenth of the height of the beam body, and the distance between the highest point of the first sub-segment and the top surface of the beam body and the distance between the highest point of the third sub-segment and the top surface of the beam body are both greater than or equal to one fifth of the height of the beam body;

[0006] The second prestressed wire body is a straight line, and a distance between the second prestressed wire body and the bottom surface of the beam body is greater than or equal to one tenth of the height of the beam body and less than or equal to one fifth of the height of the beam body.

[0007] As a preferred solution, the second sub-line segment is an axisymmetric figure having a central axis, and the first sub-line segment and the third sub-line segment are symmetrically arranged about the central axis.

[0008] As a preferred solution, the ratio of the length of the first sub-segment in the length direction of the beam body to the length of the beam body is greater than or equal to 0.05 and less than or equal to 0.15.

[0009] As a preferred solution, the expression of the first prestressed wire body includes Formula 1 and Formula 2:

[0010] Formula 1: where 0 <x<aL;

[0011] Formula 2: Where aL≤x≤0.5L;

[0012] Among them, y1 is the coordinate value of a point on the first sub-segment in the height direction with the lowest point of the second sub-segment as the zero point, and the unit is mm; y2 is the coordinate value of a point on the second sub-segment in the height direction, and the unit is mm; x is the horizontal distance between a point on the first prestressed wire and the zero point, and the zero point is the endpoint of the first sub-segment away from the second sub-segment, and the unit is mm; a is the ratio of the horizontal distance between the first inflection point and the zero point to the length of the first prestressed wire in the horizontal direction; it is dimensionless; e is the height difference between the highest point of the first sub-segment and the lowest point of the second sub-segment, and the unit is mm.

[0013] As a preferred solution, there are multiple first prestressed wire bodies, and each of the first prestressed wire bodies is arranged in parallel and spaced along the front-to-back direction; there are multiple second prestressed wire bodies, and each of the second prestressed wire bodies is arranged in parallel and spaced along the front-to-back direction.

[0014] As a preferred solution, the ratio of the number of the second prestressed wires to the number of the first prestressed wires is greater than or equal to 0.3 and less than or equal to 0.5.

[0015] A design method for the above-mentioned building structure includes the following steps:

[0016] According to the expression of the first prestressed wire, the expression of the equivalent load applied by the first prestressed wire on the beam is obtained;

[0017] According to the expression of the equivalent load applied by the first prestressed wire on the beam, the total additional bending moment applied by the first prestressed wire on the end of the beam is obtained;

[0018] According to the preload forces of the first prestressed wire and the second prestressed wire, the eccentric bending moment exerted by the first prestressed wire on the beam and the eccentric bending moment exerted by the second prestressed wire on the beam are obtained;

[0019] Using the moment distribution method, the expressions for the comprehensive bending moments at the beam ends and the column ends are derived based on the eccentric bending moment exerted by the first prestressed wire on the beam, the eccentric bending moment exerted by the second prestressed wire on the beam, and the first additional bending moment exerted by the equivalent prestressed wire on the beam.

[0020] According to the expressions of the comprehensive bending moment at the beam ends and the comprehensive bending moment at the column ends, the line shape of the first prestressed wire body is adjusted so that the absolute value of the comprehensive bending moment at the beam ends is close to the inherent bending moment of the beam ends under the action of constant load and live load, and the absolute value of the comprehensive bending moment at the column ends is close to the inherent bending moment value of the column ends under the action of constant load and live load.

[0021] As a preferred solution, the comprehensive bending moment at the beam end is:

[0022] M 梁 =0.4N P1 e×(2-a)-0.4c(N p1 +N p2 );

[0023] The comprehensive bending moment at the column end is:

[0024] M 柱 =0.2N P1 e×(1+2a)-0.6c(N p1 +N p2 );

[0025] Among them, N P1 is the preload force of the first prestressed wire, in kN; e is the sagittal height of the first prestressed wire, in mm; a is the ratio of the length of the first sub-segment in the direction of the beam length to the length of the beam, dimensionless; c is the vertical distance from the lowest point of the second sub-segment to the neutral axis of the beam, in mm; N P2 is the prestressing force of the second prestressed wire, unit is kN.

[0026] 9. A construction method for a building structure, characterized by comprising the following steps:

[0027] Step S1, processing beam reinforcement frames and column reinforcement frames;

[0028] Step S2, installing the first prestressed steel wire and the second prestressed steel wire in the beam reinforcement frame and the column reinforcement frame;

[0029] Step S3, pouring concrete on the beam reinforcement frame and column reinforcement frame;

[0030] Step S4: tensioning the first prestressed wire body and the second prestressed wire body.

[0031] 10. The construction method of a building structure according to claim 9, wherein step S4 comprises:

[0032] Step S41: tensioning the first prestressed wire so that the first prestressed wire provides a reverse equivalent load to balance the constant load of the beam;

[0033] Step S42: tensioning the second prestressed wire.

[0034] Compared with the prior art, the present invention has the following beneficial effects:

[0035] The building structure of the present invention includes a first column, a second column and a beam, the first column and the second column are arranged in parallel and spaced apart, and the two ends of the beam are respectively arranged on the first column and the second column; a first prestressed wire body and a second prestressed wire body are provided in the beam; the first prestressed wire body includes a first sub-segment, a second sub-segment and a third sub-segment connected in sequence along the length direction of the beam; the second sub-segment is a parabola with an opening facing upward, the first sub-segment and the third sub-segment are both parabolas with an opening facing downward, and the distance between the lowest point of the second sub-segment and the bottom surface of the beam is greater than or equal to one tenth of the height of the beam. One of the above, the distance between the highest point of the first sub-segment and the top surface of the beam body and the distance between the highest point of the third sub-segment and the top surface of the beam body are both greater than or equal to one-fifth of the height of the beam body; thereby, the sagitta of the first prestressed wire body is set lower; the second prestressed wire body is a straight line, and the distance between the second prestressed wire body and the bottom surface of the beam body is greater than or equal to one-tenth of the height of the beam body and less than or equal to one-fifth of the height of the beam body. By setting the sagitta of the first prestressed wire body lower and additionally arranging the second prestressed wire body, the large unbalanced bending moment generated at the end of the beam and the end of the column is reduced. BRIEF DESCRIPTION OF THE DRAWINGS

[0036] Figure 1 This is a schematic diagram of the arrangement of prestressed wires in existing building structures;

[0037] Figure 2 This is a CAE simulation analysis diagram of the combined bending moment generated by the prestressed wires in the existing building structure and the inherent bending moment of the building structure when the analysis result values are not displayed;

[0038] Figure 3 To show the numerical value of the analysis results, a CAE analysis diagram of the combined bending moment generated by the prestressed wire body in the existing building structure and the inherent bending moment of the building structure;

[0039] Figure 4 Schematic diagram of CAE simulation analysis of the combined bending moment generated by the first prestressed linear body and the second prestressed linear body in the building structure of the present invention and the inherent bending moment of the building structure when the analysis result values are not displayed;

[0040] Figure 5A schematic diagram of a CAE simulation analysis of the combined bending moment generated by the first prestressed linear body and the second prestressed linear body in the building structure of the present invention and the inherent bending moment of the building structure is provided to display the numerical value of the analysis result;

[0041] Figure 6 Schematic diagram of the physical meaning of each parameter used in the formula of the present invention;

[0042] In the figure, 100, the first column, 200, the second column, 300, the beam, 400, the existing prestressed wire, 1, the first prestressed wire, 11, the first sub-segment, 12, the second sub-segment, 13, the third sub-segment, 14, the inflection point, 2, the second prestressed wire, 31, the first curve, 32, the second curve, 33, the third curve, 34, the fourth curve, 35, the fifth curve, 36, the sixth curve. DETAILED DESCRIPTION

[0043] The following embodiments of the present invention are described in further detail with reference to the accompanying drawings and examples. The following examples are used to illustrate the present invention but are not intended to limit the scope of the present invention.

[0044] In the description of the present invention, it should be understood that the terms "upper", "lower", "left", "right", "top", "bottom", etc., indicating the orientation or positional relationship, are based on the orientation or positional relationship shown in the accompanying drawings, 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 limiting the present invention. It should be understood that the terms "first", "second", etc. are used in the present invention to describe various information, but such information should not be limited to these terms, which are only used to distinguish the same type of information from each other. For example, without departing from the scope of the present invention, "first" information may also be referred to as "second" information, and similarly, "second" information may also be referred to as "first" information.

[0045] The existing prestressed cast-in-place concrete structure was analyzed using CAE analysis software, and the stress distribution was obtained as follows: Figures 1 to 3As shown, the first curve 31 is a combined bending moment distribution curve of the beam 300 under the action of a constant load and a live load during service, obtained according to the use requirements of the building structure, and the endpoint values at the left and right ends of the first curve 31 are the inherent bending moments at the beam ends; the second curve 32 is a combined bending moment distribution curve of the first column 100 under the action of a constant load and a live load during service, obtained according to the use requirements of the building structure, and the endpoint value at the upper end of the second curve 32 is the inherent bending moment at the first column end; the third curve 33 is a combined bending moment distribution curve of the second column 200 under the action of a constant load and a live load during service, obtained according to the use requirements of the building structure, and the endpoint value at the upper end of the third curve 33 is the inherent bending moment at the second column end; the third curve 33 is bilaterally symmetrical with the second curve 32, and the inherent bending moment at the first column end is equal to the inherent bending moment at the second column end. The first curve 31 is a bilaterally symmetrical axisymmetric figure, and the endpoint values at both ends of the first curve 31 are equal. The fourth curve 34 is a distribution curve of the bending moment generated by the setting of the existing prestressed wire 400 on the beam 300, the fifth curve 35 is a distribution curve of the bending moment generated by the setting of the existing prestressed wire 400 on the first column 100, and the sixth curve 36 is a distribution curve of the bending moment generated by the setting of the existing prestressed wire 400 on the second column 200. The upper end point value of the fifth curve 35 is the first column end comprehensive bending moment, which refers to the bending moment generated by the setting of the prestressed wire 400. The sixth curve 36 is a distribution curve of the bending moment generated by the setting of the existing prestressed wire 400 on the second column 200. The upper end point of 36 is the second column end comprehensive bending moment, wherein the directions of the first column end inherent bending moment and the first column end comprehensive bending moment are opposite, the directions of the second column end inherent bending moment and the second column end comprehensive bending moment are opposite, and the directions of the beam end inherent bending moment and the beam end comprehensive bending moment are opposite. In order to improve the stress condition of the beam body 300, the ideal situation is to make the sum of the first column end inherent bending moment and the first column end comprehensive bending moment zero, the sum of the second column end inherent bending moment and the second column end comprehensive bending moment zero, and the sum of the beam end inherent bending moment and the beam end comprehensive bending moment zero.

[0046] However, in existing prestressed structure designs, the value of the comprehensive bending moment at the beam end is often much greater than the absolute value of the inherent bending moment at the beam end, and the absolute value of the comprehensive bending moment at the first column end is much smaller than the inherent bending moment at the first column end. In order to improve the stress condition of the building structure, in the present invention, the inventors have studied the arrangement of the first prestressed wire body 1 and the second prestressed wire body 2, so that the value of the comprehensive bending moment at the beam end generated by the combined action of the first prestressed wire body 1 and the second prestressed wire body 2 is as small as possible, thereby reducing the sum of the inherent bending moment at the beam end and the comprehensive bending moment at the beam end, and reducing the unbalanced bending moment at the beam end; and the absolute value of the comprehensive bending moment at the first column end and the comprehensive bending moment at the second column end generated by the combined action of the first prestressed wire body 1 and the second prestressed wire body 2 is large, thereby reducing the sum of the inherent bending moment at the first column end and the comprehensive bending moment at the first column end, and the sum of the inherent bending moment at the second column end and the comprehensive bending moment at the second column end, thereby reducing the unbalanced bending moment at the column end.

[0047] like Figures 4 to 6 As shown, a preferred embodiment of a building structure of the present invention includes a first column 100, a second column 200 and a beam 300, wherein the first column 100 and the second column 200 are arranged in parallel and spaced apart, and the two ends of the beam 300 are respectively arranged on the first column 100 and the second column 200; a first prestressed wire body 1 and a second prestressed wire body 2 are provided in the beam 300; the first prestressed wire body 1 includes a first sub-segment 11, a second sub-segment 12 and a third sub-segment 13 connected in sequence along the length direction of the beam 300; the second sub-segment 12 is a parabola with an opening facing upwards, and the first sub-segment 11 and the ... The third sub-segments 13 are all parabolas with their openings facing downwards. The distance between the lowest point of the second sub-segment 12 and the bottom surface of the beam body 300 is greater than or equal to one tenth of the height of the beam body 300. The distance between the highest point of the first sub-segment 11 and the top surface of the beam body 300 and the distance between the highest point of the third sub-segment 13 and the top surface of the beam body 300 are both greater than or equal to one fifth of the height of the beam body 300. The second prestressed wire body 2 is a straight line. The distance between the second prestressed wire body 2 and the bottom surface of the beam body 300 is greater than or equal to one tenth of the height of the beam body 300 and less than or equal to one fifth of the height of the beam body 300. Figure 2 The fourth curve 34 is a distribution curve of the comprehensive bending moment generated by the first prestressed wire body 1 and the second prestressed wire body 2 on the beam body 300. The endpoint value of the fourth curve 34 is the comprehensive bending moment of the first beam end. The fifth curve 35 is a distribution curve of the bending moment generated by the first prestressed wire body 1 and the second prestressed wire body 2 on the first column 100. The upper endpoint value of the fifth curve 35 is the comprehensive bending moment of the first column end. Figure 1 , attached Figure 2 The comprehensive bending moment at the first beam end is reduced, while the comprehensive bending moment at the first column end is increased, which reduces the large unbalanced bending moment generated at the ends of the beam and the column.

[0048] The second sub-segment 12 is an axisymmetric figure having a central axis, and the first sub-segment 11 and the third sub-segment 13 are arranged symmetrically about the central axis. This arrangement allows the first prestressed wire 1 to form a bilaterally symmetrical axisymmetric figure, thereby ensuring symmetrical forces at the ends of the beam 300 and facilitating force balance within the beam 300.

[0049] As shown in Table 1, Examples 1 and 2, and Comparative Examples 3 to 6, simulated using CAE software, compare the bending moments generated by different prestressed wire configurations. The unfavorable bending moment at the beam end in this table refers to the sum of the inherent bending moment at the beam end and the combined bending moment at the beam end, while the unfavorable bending moment at the column end refers to the sum of the inherent bending moment at the column end and the combined bending moment at the column end. ; Example 1 is a moment simulation result of a building structure when a parabolic prestressed wire body with low sagitta and a straight prestressed wire body with an inflection point coefficient of 0.1 is set; Example 2 is a moment simulation result of a building structure when a parabolic prestressed wire body with low sagitta and a straight prestressed wire body with an inflection point coefficient of 0.2 is set; Comparative Example 1 is a moment simulation result of a building structure when only a parabolic prestressed wire body with low sagitta is set and an inflection point coefficient of 0.1 is set; Comparative Example 2 is a moment simulation result of a building structure when only a parabolic prestressed wire body with high sagitta is set and an inflection point coefficient of 0.1 is set; Comparative Example 3 is a moment simulation result of a building structure when only a parabolic prestressed wire body with low sagitta is set and an inflection point coefficient of 0.2 is set. The moment simulation results of the building structure when the coefficient is 0.2; Comparative Example 4 is the moment simulation results of the building structure when only a parabolic prestressed wire body with high sagitta is set and the inflection point coefficient is 0.2; Comparative Example 5 is the moment simulation results of the building structure when a parabolic prestressed wire body with high sagitta and a straight prestressed wire body are set, and the inflection point coefficient is 0.2; Comparative Example 6 is the moment simulation results of the building structure when a parabolic prestressed wire body with high sagitta and a straight prestressed wire body are set, and the inflection point coefficient is 0.1; wherein, the comprehensive bending moment at the beam end and the comprehensive bending moment at the column end in each embodiment and comparative example are the combined action results of the parabolic prestressed wire body and the straight prestressed wire body.

[0050] Table 1

[0051]

[0052]

[0053] According to the results in Table 1, in terms of the selection of the rise-to-span ratio, the low-rise prestressed wire arrangement has smaller adverse bending moments at the beam ends and column ends than the high-rise arrangement, which is more beneficial to the stress of the building structure. For the parabolic prestressed wire, in terms of the selection of the inflection point coefficient, the steel strand linear design with an inflection point 14 position of 0.2 and 0.1 has little difference in the effect on the stress at the beam and column ends. Moreover, the arrangement of a linear prestressed wire plus a parabolic prestressed wire is more beneficial to the stress of the beam and column than the arrangement of a simple parabolic prestressed wire.

[0054] In this embodiment, the ratio of the length of the first sub-segment 11 along the length of the beam body 300 to the length of the beam body 300 is greater than or equal to 0.1 and less than or equal to 0.2. The second sub-segment 12 is bilaterally symmetrical with the first sub-segment 11. By controlling the ratio of the length of the first sub-segment 11 along the length of the beam body 300 to the length of the beam body 300, the magnitude of the integrated bending moment at the column end can be adjusted. For ease of description, in this embodiment, the ratio of the length of the first sub-segment 11 along the length of the beam body 300 to the length of the beam body 300 is defined as the inflection point coefficient.

[0055] In this embodiment, in order to further improve the structural strength of the beam body 300, a plurality of first prestressed wire bodies 1 are provided, and each of the first prestressed wire bodies 1 is arranged in parallel and spaced apart in the front-to-back direction; a plurality of second prestressed wire bodies 2 are provided, and each of the second prestressed wire bodies 2 is arranged in parallel and spaced apart in the front-to-back direction. The ratio of the number of the second prestressed wire bodies 2 to the number of the first prestressed wire bodies 1 is greater than or equal to 0.3 and less than or equal to 0.5. By increasing the number of the second prestressed wire bodies 2, the comprehensive bending moment at the beam end can be reduced, and the comprehensive bending moment at the column end can be increased. However, if the proportion of the second prestressed wire bodies 2 is too large, the comprehensive bending moment at the beam end will be too small, which will also cause the unbalanced bending moment at the beam end to increase in the opposite direction. In this embodiment, the ratio of the number of the second prestressed wire bodies 2 to the number of the first prestressed wire bodies 1 is set to 0.5, so as to ensure that the comprehensive bending moment at the beam end and the comprehensive bending moment at the column end are within a reasonable range.

[0056] In this embodiment, the first prestressed wire 1 and the second prestressed wire 2 are both steel strands. The expression of the first prestressed wire 1 includes formula 1 and formula 2:

[0057] Formula 1: where 0 <x<aL;

[0058] Formula 2: Where aL≤x≤0.5L;

[0059] Among them, y1 is the coordinate value of a point on the first sub-segment 11 in the height direction with the first zero point as the reference point, wherein the first zero point is the lowest point of the second sub-segment 12, and the unit is mm; y2 is the coordinate value of a point on the second sub-segment 12 in the height direction, and the unit is mm; x is the horizontal distance between a point on the first prestressed wire body 1 and the second zero point, wherein the second zero point is the endpoint of the first sub-segment 11 away from the second sub-segment 12, and the unit is mm; a is the ratio of the length of the first sub-segment 11 in the length direction of the beam body 300 to the length of the beam body 300; it is dimensionless; e is the height difference between the highest point of the first sub-segment 11 and the lowest point of the second sub-segment 12, and the unit is mm.

[0060] A design method for the above-mentioned building structure includes the following steps:

[0061] According to the expression of the first prestressed wire body 1, the expression of the equivalent load applied by the first prestressed wire body 1 to the beam body 300 is obtained; specifically, the equivalent load applied by the first prestressed wire body 1 to the beam body 300 is the uniformly distributed load applied by the first prestressed wire body 1 to the beam body 300; in this step, it is assumed that the transverse length of the beam body 300 is L, the length of the first sub-segment 11 is aL, the length of the second sub-segment 12 is bL, the beam height is h, and the effective prestress value of the first prestressed wire body 1 is N p1 , the effective prestress value of the second prestressed wire 2 is N p2 Where a is the inflection point coefficient, 2a + b = 1, e1 is the vertical distance from the highest point of the first sub-segment 11 to the inflection point 14, e2 is the vertical distance from the lowest point of the second sub-segment 12 to the inflection point 14, e0 is the vertical distance from the highest point of the first sub-segment 11 to the neutral axis of the beam 300, C is the vertical distance from the lowest point of the second sub-segment 12 to the neutral axis of the beam 300, e is the sagittal height of the first prestressed wire 1, e0 + c = e1 + e2 = e, the downward uniformly distributed load within the length aL at the left and right ends of the beam 300 is q1, and the upward uniformly distributed load q2 is applied to the bL section in the middle of the beam 300. According to the prestressed equivalent load calculation theory, the following is obtained:

[0062] Formula 3: q1 = 8 * N p1 *e1 / (2aL) 2

[0063] Formula 4: q2 = 8*N p1 *e2 / (L-2aL) 2

[0064] At the inflection point 14, that is, when X=aL, according to formula 1, we can get:

[0065] Formula 5:

[0066] According to Formula 5 and e1+e2=e, we can deduce:

[0067] Formula 6: e1 = 2ae;

[0068] Substituting formula 6 into formula 3, we can get:

[0069] Formula 7:

[0070] Substituting Formula 5 into Formula 4, we can get:

[0071] Formula 8:

[0072] Wherein, Formula 7 and Formula 8 are expressions for the equivalent load applied by the first prestressed linear body 1 to the beam body 300 .

[0073] According to the expression of the equivalent load applied by the first prestressed wire 1 to the beam 300, that is, formula 7 and formula 8, the expression of the additional bending moment applied by the equivalent load of the first prestressed wire 1 to the beam 300 can be obtained; specifically, the additional bending moment applied by the equivalent load of the first prestressed wire 1 to the beam 300 includes M q1 and M q2 , M q1 is the additional bending moment imposed on the beam 300 by the uniformly distributed load q1, M q2 is the additional bending moment imposed on the beam 300 by the uniformly distributed load q2, where:

[0074]

[0075] According to M q1 and M q2 , we can get the total additional bending moment M exerted by the equivalent load of the first prestressed wire 1 on the end of the beam 300 总附 :

[0076] Formula 9:

[0077] In addition to the M generated by the uniform load q1 and the uniform load q2 总附 In addition, the first prestressed wire 1 also applies an eccentric bending moment M1 to the beam 300, and the second prestressed wire 2 applies an eccentric bending moment M2 to the beam 300. According to the preload force N of the first prestressed wire 1, P1 , the eccentric bending moment M1 exerted by the first prestressed wire 1 on the beam 300 is obtained as:

[0078] Formula 10: M1=-N p1 *e0;

[0079] According to the prestressing force N of the second prestressing wire body 2 P2 , the eccentric bending moment M2 exerted by the first prestressed wire 1 on the beam 300 is obtained as:

[0080] Formula 11: M2=Np2*c;

[0081] According to Formula 10 and Formula 11, the total eccentric bending moment M exerted by the first prestressed wire 1 and the second prestressed wire 2 on the beam 300 can be obtained as follows: 总偏 for:

[0082] Formula 12: M 总偏 =M1+M2=N p2 cN p1 e0=c(N p1 +Np2 )-N p1 e

[0083] Using the moment distribution method, assuming that the column end moment distribution coefficient is i=0.4, the beam end moment distribution coefficient is 0.6. According to the eccentric bending moment applied by the first prestressed wire 1 to the beam body 300, the eccentric bending moment applied by the second prestressed wire 2 to the beam body 300, and the additional bending moment applied by the uniformly distributed load of the first prestressed wire 1 to the beam body 300, the comprehensive bending moment M at the beam end is obtained. 梁 The expression of column end comprehensive bending moment M 柱 Expressions of

[0084] M 梁 =M 总附 -0.4(M 总偏 +M 总附 )=0.4N P1 e×(2-a)-0.4c(N p1 +N p2 )

[0085] M 柱 =-0.6(M 总偏 +M 总附 )=0.2N P1 e×(1+2a)-0.6c(N p1 +N p2 )

[0086] Afterwards, according to M 梁 and M 柱 The expression of is used to adjust the line shape of the first prestressed wire body 1 so that the absolute value of the comprehensive bending moment at the beam end is close to the inherent bending moment at the beam end, and the absolute value of the comprehensive bending moment at the column end is close to the inherent bending moment value at the column end; wherein, the inherent bending moment value at the beam end is the bending moment value of the end of the beam body 300 under the action of constant load and live load, the bending moment value at the column end is the bending moment value of the upper end of the first column 100 or the second column 200 under the action of constant load and live load, the comprehensive bending moment value at the beam end is the bending moment value applied to the end of the beam body 300 by the arrangement of the first prestressed wire body 1 and the second prestressed wire body 2, and the comprehensive bending moment value at the column end is the bending moment value applied to the upper end of the first column 100 or the second column 200 by the arrangement of the first prestressed wire body 1 and the second prestressed wire body 2.

[0087] Specifically, according to the parabolic arrangement of the first prestressed line 1, we know that e∈(c,2c), a∈(0,0.25). The principle of optimizing the prestressed line is to minimize the composite bending moment at the beam end as much as possible, close to the inherent bending moment at the beam end under the action of dead load + live load; and to maximize the absolute value of the composite bending moment at the column section as much as possible, large enough to offset the inherent bending moment at the column end under the action of dead load + live load. Based on the above principles and parameter value ranges, it can be inferred that: Np2 The existence of the parabolic prestressed line body is changed to a straight prestressed line body, which can effectively weaken the M 梁 At the same time, enhance M 柱 , which is beneficial to the stress of the building structure; moreover, the smaller the value of e, that is, the smaller the sagittal height of the first prestressed wire 1, the more conducive to reducing M 梁 ; The increase of a is conducive to reducing M 梁 , but the magnitude of the reduction was far less than the effect of the change in e. Based on the above analysis, the prestressed wire arrangement was determined to have a ratio of 2:1 between the first prestressed wire 1 and the second prestressed wire 2, and the sagitta of the first prestressed wire 1 was reduced. This revolutionary design significantly optimized the structural load-bearing performance of the building, significantly reducing the unbalanced bending moments at the beam / column ends, achieving a dual reduction in bending moments at the beam and column ends, and yielding significant project benefits.

[0088] An embodiment of the above-mentioned construction method of the building structure comprises the following steps:

[0089] Step S1, processing beam reinforcement frames and column reinforcement frames;

[0090] Step S2, installing the first prestressed wire body 1 and the second prestressed wire body 2 in the beam reinforcement frame and the column reinforcement frame;

[0091] Step S3, pouring concrete on the beam reinforcement frame and column reinforcement frame;

[0092] Step S4: tensioning the first prestressed wire body 1 and the second prestressed wire body 2.

[0093] The provision of the second prestressed wire bodies 2 reduces the number of the first prestressed wire bodies 1 , thereby avoiding the construction inconvenience caused by the overly dense arrangement of the first prestressed wire bodies 1 .

[0094] Furthermore, the step S4 includes:

[0095] Step S41: tensioning the first prestressed wire 1 so that the first prestressed wire 1 provides a reverse equivalent load to balance the constant load of the beam 300;

[0096] Step S42: tensioning the second prestressed wire 2.

[0097] The first prestressed wire 1 is tensioned first, providing a large reverse equivalent load to balance the existing dead load. The second prestressed wire 2 is then tensioned. This tensioning sequence is key to ensuring the full performance of the prestressed structure and is an important step in verifying the quality of the entire construction process. The first and second prestressed wires 1 and 2 are dispersed, and compared to existing construction plans, the number of parabolic prestressed wires is reduced. Straight prestressed wires are easier to construct and less expensive than parabolic prestressed wires, reducing both construction difficulty and cost.

[0098] In summary, the building structure of the present invention includes a first column 100, a second column 200 and a beam 300, the first column 100 and the second column 200 are arranged in parallel and spaced apart, and the two ends of the beam 300 are respectively arranged on the first column 100 and the second column 200; a first prestressed wire body 1 and a second prestressed wire body 2 are provided in the beam 300; the first prestressed wire body 1 includes a first sub-segment 11, a second sub-segment 12 and a third sub-segment 13 connected in sequence along the length direction of the beam 300; the second sub-segment 12 is a parabola with an opening facing upward, the first sub-segment 11 and the second sub-segment 12 are both parabolas with an opening facing downward, and the distance between the lowest point of the second sub-segment 12 and the bottom surface of the beam 300 is The distance between the highest point of the first sub-segment 11 and the top surface of the beam body 300 and the distance between the highest point of the second sub-segment 12 and the top surface of the beam body 300 are both greater than or equal to one-fifth of the height of the beam body 300; thereby, the sagitta of the first prestressed wire body 1 is set lower; the second prestressed wire body 2 is a straight line, and the distance between the second prestressed wire body 2 and the bottom surface of the beam body 300 is greater than or equal to one-tenth of the height of the beam body 300 and less than or equal to one-fifth of the height of the beam body 300. By setting the sagitta of the first prestressed wire body 1 lower and additionally setting the second prestressed wire body 2, the large unbalanced bending moment generated at the end of the beam and the end of the column is reduced.

[0099] The above is only a preferred embodiment of the present invention. It should be pointed out that for ordinary technicians in this technical field, several improvements and substitutions can be made without departing from the technical principles of the present invention. These improvements and substitutions should also be regarded as the scope of protection of the present invention.

Claims

1. A building structure comprising a first column, a second column, and a beam, wherein the first column and the second column are arranged in parallel and spaced apart, and two ends of the beam are respectively disposed on the first column and the second column; The beam body is provided with a first prestressed wire body and a second prestressed wire body; the first prestressed wire body includes a first sub-segment, a second sub-segment and a third sub-segment connected in sequence along the length direction of the beam body; the first sub-segment and the third sub-segment are both parabolas with openings facing downward, the second sub-segment is a parabola with openings facing upward, the distance between the lowest point of the second sub-segment and the bottom surface of the beam body is greater than or equal to one tenth of the height of the beam body, and the distance between the highest point of the first sub-segment and the top surface of the beam body and the distance between the highest point of the third sub-segment and the top surface of the beam body are both greater than or equal to one fifth of the height of the beam body; The second prestressed wire body is a straight line, and a distance between the second prestressed wire body and the bottom surface of the beam body is greater than or equal to one tenth of the height of the beam body and less than or equal to one fifth of the height of the beam body.

2. The building structure according to claim 1, characterized in that The second sub-line segment is an axisymmetric figure having a central axis, and the first sub-line segment and the third sub-line segment are symmetrically arranged about the central axis.

3. The building structure according to claim 2, characterized in that A ratio of a length of the first sub-segment in the length direction of the beam body to the length of the beam body is greater than or equal to 0.05 and less than or equal to 0.

15.

4. The building structure according to claim 2, characterized in that The expression of the first prestressed linear body includes formula 1 and formula 2: Formula 1: where 0 <x<aL; Formula 2: Where aL≤x≤0.5L; Among them, y1 is the coordinate value of a point on the first sub-segment in the height direction with the lowest point of the second sub-segment as the zero point as the reference, and the unit is mm; y2 is the coordinate value of a point on the second sub-segment in the height direction, and the unit is mm; x is the horizontal distance between a point on the first prestressed wire and the zero point, and the zero point is the endpoint of the first sub-segment away from the second sub-segment, and the unit is mm; a is the ratio of the horizontal distance between the first inflection point and the zero point to the length of the first prestressed wire in the horizontal direction; it is dimensionless; e is the height difference between the highest point of the first sub-segment and the lowest point of the second sub-segment, and the unit is mm.

5. The building structure according to claim 1, characterized in that There are a plurality of first prestressed wire bodies, and each of the first prestressed wire bodies is arranged in parallel and spaced along the front-to-back direction; there are a plurality of second prestressed wire bodies, and each of the second prestressed wire bodies is arranged in parallel and spaced along the front-to-back direction.

6. The building structure according to claim 5, characterized in that The ratio of the number of the second prestressed wires to the number of the first prestressed wires is greater than or equal to 0.3 and less than or equal to 0.

5.

7. A design method for a building structure according to claim 1, characterized in that: The following steps are involved: According to the expression of the first prestressed wire, the expression of the equivalent load applied by the first prestressed wire on the beam is obtained; According to the expression of the equivalent load applied by the first prestressed wire on the beam, the total additional bending moment applied by the equivalent load of the first prestressed wire on the end of the beam is obtained; According to the preload forces of the first prestressed wire and the second prestressed wire, the eccentric bending moment exerted by the first prestressed wire on the beam and the eccentric bending moment exerted by the second prestressed wire on the beam are obtained; Using the moment distribution method, the expressions for the comprehensive bending moments at the beam ends and the column ends are derived based on the eccentric bending moment exerted by the first prestressed wire on the beam, the eccentric bending moment exerted by the second prestressed wire on the beam, and the first additional bending moment exerted by the equivalent load of the first prestressed wire on the beam. According to the expressions of the comprehensive bending moment at the beam ends and the comprehensive bending moment at the column ends, the line shape of the first prestressed wire body is adjusted so that the absolute value of the comprehensive bending moment at the beam ends is close to the inherent bending moment of the beam ends under the action of constant load and live load, and the absolute value of the comprehensive bending moment at the column ends is close to the inherent bending moment value of the column ends under the action of constant load and live load.

8. The design method of a building structure according to claim 7, characterized in that: The comprehensive bending moment at the beam end is: M 梁 =0.4N P1 e×(2-a)-0.4c(N p1 +N p2 ); The comprehensive bending moment at the column end is: <h2 style=";text-align:left;direction:ltr">M<h2 style=";text-align:left;direction:ltr"> 柱 <h2 style=";text-align:left;direction:ltr"> <0.2N<h2 style=";text-align:left;direction:ltr"> P1 <h2 style=";text-align:left;direction:ltr"> e×(1+2a)-0.6c(N<h2 style=";text-align:left;direction:ltr"> p1 <h2 style=";text-align:left;direction:ltr"> +N<h2 style=";text-align:left;direction:ltr"> p2 <h2 style=";text-align:left;direction:ltr"> ); Among them, N P1 is the preload force of the first prestressed wire, in kN; e is the sagittal height of the first prestressed wire, in mm; a is the ratio of the length of the first sub-segment in the direction of the beam length to the length of the beam, dimensionless; c is the vertical distance from the lowest point of the second sub-segment to the neutral axis of the beam, in mm; N P2 is the prestressing force of the second prestressed wire, unit is kN.

9. A construction method for a building structure, characterized in that: The following steps are involved: Step S1, processing beam reinforcement frames and column reinforcement frames; Step S2, installing the first prestressed steel wire and the second prestressed steel wire in the beam reinforcement frame and the column reinforcement frame; Step S3, pouring concrete on the beam reinforcement frame and column reinforcement frame; Step S4: tensioning the first prestressed wire body and the second prestressed wire body.

10. The construction method of a building structure according to claim 9, characterized in that: The step S4 comprises: Step S41: tensioning the first prestressed wire so that the first prestressed wire provides a reverse equivalent load to balance the constant load of the beam; Step S42: tensioning the second prestressed wire.

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