New and old bent cap connecting structure and stress calculation method thereof

Abstract

The invention discloses a new and old cover beam connecting structure and a stress calculation method thereof. The new and old cover beam connecting structure comprises a plurality of anchor bolt sets, a restraint rope and an elastic plate arranged in a splicing seam between a new cover beam and an old cover beam. A plurality of groups of anchor bolts fixed on the side wall of a new bent cap and a plurality of groups of anchor bolts fixed on the side wall of an old bent cap are connected by the restraint rope in an 8-shaped connection mode, so that the horizontal displacement of one side of the new bent cap can be well restrained; the elastic plate is arranged in the splicing seam between the new cover beam and the old cover beam, certain vertical relative settlement is allowed to be generated between the new cover beam and the old cover beam through shear deformation of the elastic plate and elastic extension of the restraint rope, and certain elastic compression deformation can be achieved in the horizontal direction of the elastic plate, so that force transmission between the new cover beam and the old cover beam is mild; the local damage phenomenon caused by stress concentration due to hard contact between the concrete can be effectively avoided.

Description

Technical Field

[0001] The invention relates to the field of bridge splicing, and in particular to a new and old cap beam connection structure and a force calculation method thereof. Background Art

[0002] The new bridge section of the highway reconstruction and expansion project is often arranged with one lane, so a single-column pier structure is often used, which has poor stability and needs to rely on the lower structure of the old bridge to horizontally constrain the newly widened structure. If the soil layer in the project area is relatively soft and thick, the friction pile foundation is used, and its end cannot penetrate into the rock layer. The new lower structure will produce a certain vertical settlement under the load transmitted from the upper part, and may even have a tendency to overturn under the action of eccentric load. During the construction process, due to the influence of many factors such as the construction period, it is impossible to meet the prerequisite that the new bridge side can start subsequent construction after a certain period of natural settlement.

[0003] Therefore, a new and old joint connection method is needed that can continue construction while maintaining traffic flow, has a reasonable structure, excellent mechanical properties, and allows a certain difference in settlement between the new and old structures. Summary of the invention

[0004] The purpose of the present invention is to provide a new and old cap beam connection structure and a force calculation method thereof, so as to solve the problem of differential settlement in the current bridge splicing method and improve the stability of the newly built structure.

[0005] In order to solve the above technical problems, in a first aspect, the present invention provides a new and old cap beam connection structure, comprising a first anchor bolt group, a second anchor bolt group, a restraining rope, and an elastic plate arranged in a joint between a new cap beam and an old cap beam;

[0006] The first anchor bolt group includes a first anchor bolt and a second anchor bolt, the first anchor bolt is arranged on the side wall of the new cap beam, and the second anchor bolt is arranged on the side wall of the old cap beam; the second anchor bolt group includes a third anchor bolt and a fourth anchor bolt, the third anchor bolt is arranged on the side wall of the new cap beam, and the fourth anchor bolt is arranged on the side wall of the old cap beam; the third anchor bolt and the fourth anchor bolt are arranged below the first anchor bolt and the second anchor bolt;

[0007] The restraining rope is wound in an 8-shape with each anchor bolt as a steering wheel and connected between the first anchor bolt and the second anchor bolt. After a set tension is applied to the restraining rope, the end to end is connected to form a closed annular structure with a preset tension, so that the elastic plate is subjected to lateral pressure. Furthermore, the first anchor bolt and the second anchor bolt are symmetrically arranged on both sides of the joint between the new and old cap beams.

[0008] Furthermore, the third anchor bolt and the fourth anchor bolt are symmetrically arranged on both sides of the joint between the new and old cap beams, and the spacing between the third anchor bolt and the fourth anchor bolt is equal to the spacing between the first anchor bolt and the second anchor bolt.

[0009] Furthermore, the structure also includes at least one third anchor group arranged between the first anchor group and the second anchor group; the third anchor group includes a fifth anchor and a sixth anchor symmetrically arranged on both sides of the joint, the fifth anchor is arranged on the side wall of the new cap beam, and the sixth anchor is arranged on the side wall of the old cap beam, and the spacing between the fifth anchor and the sixth anchor is equal to the spacing between the first anchor and the second anchor; the restraint rope is connected in a continuous 8 shape between the first anchor, the second anchor, the third anchor, the fourth anchor, the fifth anchor and the sixth anchor.

[0010] Furthermore, when a third anchor group is arranged between the first anchor group and the second anchor group, the first anchor group and the third anchor group, as well as the third anchor group and the second anchor group are arranged at equal intervals; when the number of third anchor groups is greater than or equal to 2, the third anchor group and the third anchor group, the first anchor group and the third anchor group, and the third anchor group and the second anchor group are arranged at equal intervals.

[0011] Furthermore, the elastic plate is a rubber plate.

[0012] Furthermore, the restraining rope is a steel wire rope.

[0013] In a second aspect, the present invention provides a method for calculating the force of the new and old cap beam connection structure proposed in the first aspect, comprising the steps of:

[0014] S1: Calculate the total elastic extension Δl of the restraining rope;

[0015] S2: Calculate the tension on the restraining rope according to formula (1):

[0016] F=f+ΔF=f+E·Δl·A (1)

[0017] Among them, f is the initial tension of the restraint rope, E is the elastic modulus of the restraint rope, Δl is the total elastic elongation of the restraint rope, and A is the cross-sectional area of ​​a single-strand restraint rope.

[0018] Furthermore, the calculation method of the total elastic elongation Δl of the restraining rope specifically includes:

[0019]

[0020] Δl=2(Δl 1 +Δl 2 +Δl 3 ) (5)

[0021] Among them, Δl 1 is the elastic extension of the restraining rope between the first anchor bolt and the second anchor bolt or between the third anchor bolt and the fourth anchor bolt, Δl 2 is the elastic extension of the restraining rope between the first anchor bolt and the fourth anchor bolt, Δl 3is the elastic extension of the restraining rope between the second anchor bolt and the third anchor bolt; a is the horizontal spacing of the anchor bolts; b is the vertical spacing of the anchor bolts, and t is the relative settlement of the new and old structures.

[0022] The beneficial effects of the present invention are as follows: by connecting the anchor bolts fixed on the side walls of the new and old cap beams in an 8-shaped connection manner using restraining ropes, the horizontal displacement of one side of the new cap beam can be well restrained; by arranging an elastic plate in the joint between the new cap beam and the old cap beam, a certain vertical relative settlement is allowed between the new and old cap beams through the shear deformation of the elastic plate and the elastic elongation of the restraining rope, and the elastic plate can achieve a certain elastic compression deformation in the horizontal direction, so that the force transmission between the new and old cap beams is eased, which can effectively avoid the phenomenon of stress concentration and local damage caused by hard contact between concrete. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] The drawings described herein are used to provide a further understanding of the present application and constitute a part of the present application. The same reference numerals are used in these drawings to represent the same or similar parts. The exemplary embodiments of the present application and their descriptions are used to explain the present application and do not constitute an improper limitation on the present application. In the drawings:

[0024] Figure 1 This is a structural schematic diagram of the connection structure between the new and old cap beams;

[0025] Figure 2 This is a comparison diagram of the new cap beam before and after settlement;

[0026] Figure 3 It is a schematic diagram of the local force of the connection structure between the new and old cap beams after the new cap beam settles;

[0027] Figure 4 It is a schematic diagram of the force synthesis of the connecting rope;

[0028] Figure 5 Schematic diagram of the local forces on the connecting rope and the elastic plate.

[0029] Among them: 1. new cap beam; 2. old cap beam; 3. elastic plate; 4. first anchor bolt; 41. second anchor bolt; 5. third anchor bolt; 51. fourth anchor bolt; 6. fifth anchor bolt; 61. sixth anchor bolt; 7. restraint rope 7; 71. restraint rope joint. DETAILED DESCRIPTION

[0030] In the first aspect, the present invention provides a connection structure between a new cap beam 2 and an old cap beam 2, comprising a first anchor bolt group, a second anchor bolt group, a restraining rope 7, and an elastic plate 3 arranged in a joint between a new cap beam 1 and an old cap beam 2. Figure 1 As shown;

[0031] The first anchor bolt group includes a first anchor bolt 4 and a second anchor bolt 41, the first anchor bolt 4 is arranged on the side wall of the new cap beam 1, and the second anchor bolt 41 is arranged on the side wall of the old cap beam 2; the second anchor bolt group includes a third anchor bolt 5 and a fourth anchor bolt 51, the third anchor bolt 5 is arranged on the side wall of the new cap beam 1, and the fourth anchor bolt 51 is arranged on the side wall of the old cap beam 2; the third anchor bolt 5 and the fourth anchor bolt 51 are arranged below the first anchor bolt 4 and the second anchor bolt 41;

[0032] The restraining rope 8 is wound in an 8-shape with each anchor bolt as a steering wheel and connected between the first anchor bolt and the second anchor bolt. After a set tension is applied to the restraining rope 8, the end to end is connected to form a closed annular structure with a preset tension, so that the elastic plate 3 is subjected to lateral pressure.

[0033] The present invention connects the anchor bolts fixed on the side walls of the new and old cap beams 2 in an 8-shaped connection manner using the restraining rope 7, which can effectively restrain the horizontal displacement of one side of the new cap beam 1; an elastic plate 3 is set in the joint between the new cap beam 1 and the old cap beam 2, and a certain vertical relative settlement is allowed between the new and old cap beams 2 through the shear deformation of the elastic plate 3 and the elastic elongation of the restraining rope 7, and the elastic plate 3 can achieve a certain elastic compression deformation in the horizontal direction, so that the force transmission between the new and old cap beams 2 is eased, and the hard contact between the concrete can be effectively avoided to cause stress concentration and local damage; the problem of uneven settlement of the new and old structures due to complete constraint of all-directional translation and rotation, which is prone to stress concentration and thus damage, can be avoided.

[0034] According to one embodiment of the present application, the first anchor bolt 4 and the second anchor bolt 41 are symmetrically arranged on both sides of the joint between the new and old cap beams 2. Since the relative settlement between the new and old cap beams 2 is small, the vertical component force thereof is almost negligible. The present application can better constrain the horizontal displacement between the new and old cap beams 2 by symmetrically arranging the first anchor bolt 4 and the second anchor bolt 41, that is, arranging the first anchor bolt 4 and the second anchor bolt 41 on the same horizontal plane at the initial stage of splicing; and it can also facilitate the subsequent calculation of the elastic elongation of the restraining rope between the first anchor bolt 4 and the second anchor bolt 41.

[0035] According to one embodiment of the present application, the third anchor bolt 5 and the fourth anchor bolt 51 are symmetrically arranged on both sides of the joint between the new and old cap beams 2, and the spacing between the third anchor bolt 5 and the fourth anchor bolt 51 is equal to the spacing between the first anchor bolt 4 and the second anchor bolt 41. Similarly, by symmetrically arranging the third anchor bolt 5 and the fourth anchor bolt 51, that is, arranging the third anchor bolt 5 and the fourth anchor bolt 51 on the same horizontal plane at the initial stage of splicing, the horizontal displacement between the new and old cap beams 2 can be better constrained; and the restraining rope between the third anchor bolt 5 and the fourth anchor bolt 51 can also be kept consistent with the restraining rope between the first anchor bolt 4 and the second anchor bolt 41, thereby simplifying the subsequent force calculation.

[0036] According to one embodiment of the present application, the structure further includes at least one third anchor bolt group arranged between the first anchor bolt group and the second anchor bolt group; the third anchor bolt group 5 includes a fifth anchor bolt 6 and a sixth anchor bolt 61 symmetrically arranged on both sides of the joint, the fifth anchor bolt 6 is arranged on the side wall of the new cap beam 1, the sixth anchor bolt 61 is arranged on the side wall of the old cap beam 2, and the spacing between the fifth anchor bolt 6 and the sixth anchor bolt 61 is equal to the spacing between the first anchor bolt 4 and the second anchor bolt 41; the restraining rope 7 is connected in a continuous 8-shaped shape between the first anchor bolt 4, the second anchor bolt 41, the third anchor bolt, the fourth anchor bolt 51 and the fifth anchor bolt 6 and the sixth anchor bolt 61. By means of the third anchor bolt group between the first anchor bolt group and the second anchor bolt group, the restraining stability of the restraining rope 7 on the new and old cap beams 2 can be improved.

[0037] According to an embodiment of the present application, when a third anchor bolt group is arranged between the first anchor bolt group and the second anchor bolt group, the first anchor bolt group and the third anchor bolt group and the third anchor bolt group and the second anchor bolt group are arranged at equal intervals; when the number of the third anchor bolt groups is greater than or equal to 2, the third anchor bolt group and the third anchor bolt group, the first anchor bolt group and the third anchor bolt group, and the third anchor bolt group and the second anchor bolt group are arranged at equal intervals. By arranging the first anchor bolt group, the second anchor bolt group and the third anchor bolt group at equal intervals, the stability of each anchor bolt can be ensured.

[0038] According to an embodiment of the present application, the elastic plate 3 can specifically be a rubber plate; the rubber plate has excellent elasticity and deformation ability, can effectively alleviate vibration and impact, and can maintain good performance stability in harsh environments such as high temperature, low temperature, and humidity.

[0039] According to one embodiment of the present application, the restraining rope 7 may be a steel wire rope; the steel wire rope has the characteristics of high strength, light weight, stable operation, and not easy to break suddenly, and can provide reliable restraining force.

[0040] In a second aspect, the present invention provides a method for calculating the force of the connection structure of the new and old cap beams 2 proposed in the first aspect. Figure 3 As shown, since the tension of the same wire rope is equal everywhere, that is, F 1 =F 2 =F 3 =F; therefore, the calculation method of the tension on the restraining rope 7 after deformation is as follows:

[0041] S1: Calculate the total elastic extension Δl of the restraining rope 7;

[0042] S2: Calculate the tension on the restraining rope 7 according to formula (1):

[0043] F=f+ΔF=f+E·Δl·A (1)

[0044] Wherein, f is the initial tension of the restraint rope 7, E is the elastic modulus of the restraint rope 7, Δl is the total elastic elongation of the restraint rope 7, and A is the cross-sectional area of ​​a single-strand restraint rope 7.

[0045] According to one embodiment of the present application, the method for calculating the total elastic elongation Δl of the restraint rope 7 specifically includes:

[0046]

[0047] Δl=2(Δl 1 +Δl 2 +Δl 3 ) (5)

[0048] Among them, Δl 1 is the elastic extension of the restraining rope between the first anchor bolt and the second anchor bolt or between the third anchor bolt and the fourth anchor bolt, Δl 2 is the elastic extension of the restraining rope between the first anchor bolt and the fourth anchor bolt, Δl 3 is the elastic extension of the restraining rope between the second anchor bolt and the third anchor bolt; a is the horizontal spacing of the anchor bolts; b is the vertical spacing of the anchor bolts, and t is the relative settlement of the new and old structures.

[0049] Finally, it should be noted that the above embodiments are only used to illustrate the technical solution of the present invention rather than to limit it. Although the present invention has been described in detail with reference to the preferred embodiments, those skilled in the art should understand that the technical solution of the present invention can be modified or replaced by equivalents without departing from the purpose and scope of the technical solution of the present invention, which should be included in the scope of the claims of the present invention.

Claims

1. A new and old cap beam connection structure, It is characterized in that It includes a first anchor bolt group, a second anchor bolt group, a restraining rope, and an elastic plate arranged in a joint between a new cap beam and an old cap beam; The first anchor bolt group includes a first anchor bolt and a second anchor bolt, the first anchor bolt is arranged on the side wall of the new cap beam, and the second anchor bolt is arranged on the side wall of the old cap beam; the second anchor bolt group includes a third anchor bolt and a fourth anchor bolt, the third anchor bolt is arranged on the side wall of the new cap beam, and the fourth anchor bolt is arranged on the side wall of the old cap beam; the third anchor bolt and the fourth anchor bolt are arranged below the first anchor bolt and the second anchor bolt; The restraining rope is wound in an 8-shape with each anchor bolt as a steering wheel and connected between the first anchor bolt and the second anchor bolt. After a set tension is applied to the restraining rope, the end to end is connected to form a closed annular closed structure with a preset tension, so that the elastic plate is subjected to lateral pressure.

2. The new and old cap beam connection structure according to claim 1, It is characterized in that The first anchor bolt and the second anchor bolt are symmetrically arranged on both sides of the joint between the new and old cap beams.

3. The new and old cap beam connection structure according to claim 2, It is characterized in that The third anchor bolt and the fourth anchor bolt are symmetrically arranged on both sides of the joint between the new and old cap beams, and the spacing between the third anchor bolt and the fourth anchor bolt is equal to the spacing between the first anchor bolt and the second anchor bolt.

4. The new and old cap beam connection structure according to claim 3, It is characterized in that The structure also includes at least one third anchor group arranged between the first anchor group and the second anchor group; the third anchor group includes a fifth anchor and a sixth anchor symmetrically arranged on both sides of the joint, the fifth anchor is arranged on the side wall of the new cap beam, and the sixth anchor is arranged on the side wall of the old cap beam, and the spacing between the fifth anchor and the sixth anchor is equal to the spacing between the first anchor and the second anchor; the restraint rope is connected in a continuous 8-shape between the first anchor, the second anchor, the third anchor, the fourth anchor and the fifth anchor and the sixth anchor.

5. The new and old cap beam connection structure according to claim 4, It is characterized in that When a group of the third anchor bolt group is arranged between the first anchor bolt group and the second anchor bolt group, the first anchor bolt group and the third anchor bolt group, as well as the third anchor bolt group and the second anchor bolt group are arranged at equal intervals; when the number of the third anchor bolt groups is greater than or equal to 2, the third anchor bolt group and the third anchor bolt group, the first anchor bolt group and the third anchor bolt group, and the third anchor bolt group and the second anchor bolt group are arranged at equal intervals.

6. The new and old cap beam connection structure according to claim 1, It is characterized in that The elastic plate is a rubber plate.

7. The new and old cap beam connection structure according to claim 1, It is characterized in that The restraining rope is a steel wire rope.

8. A method for calculating the force of the new and old cap beam connection structure according to any one of claims 1 to 7, It is characterized in that Includes steps: S1: Calculate the elastic extension Δl of the restraining rope; S2: Calculate the tension on the restraining rope according to formula (1): F=f+ΔF=f+E·Δl·A (1) Among them, f is the initial tension of the restraint rope, E is the elastic modulus of the restraint rope, Δl is the elastic elongation of the restraint rope, and A is the cross-sectional area of ​​a single-strand restraint rope.

9. The force calculation method according to claim 8, It is characterized in that The calculation of the elastic elongation Δl of the restraint rope specifically includes: Δl=2(Δl 1 +Δl 2 +Δl 3 ) (5) Among them, Δl 1 is the elastic extension of the restraining rope between the first anchor bolt and the second anchor bolt or between the third anchor bolt and the fourth anchor bolt, Δl 2 is the elastic extension of the restraining rope between the first anchor bolt and the fourth anchor bolt, Δl 3 is the elastic extension of the restraining rope between the second anchor bolt and the third anchor bolt; a is the horizontal spacing of the anchor bolts; b is the vertical spacing of the anchor bolts, and t is the relative settlement of the new and old structures.

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