JP5964129B2 - Design method, design apparatus, and design program for reinforced concrete beam or column having openings - Google Patents

Description

  The present invention relates to a design method, a design apparatus, and a design program for a reinforced concrete beam or column having an opening.

  As a guideline of the Architectural Institute of Japan in providing openings in beams and columns of reinforced concrete structures, “Guidelines for ultimate strength type seismic design for RC buildings” (Guideline for ultimate strength design for RC buildings) and “Guidelines for seismic design for toughness guaranteed RC buildings” (Toughness guidelines) (see Non-Patent Document 1).

In Non-Patent Document 1, that is, the Architectural Institute of Japan, the shear reliability strength is given on the condition that the required reinforcement range is satisfied for the shear reinforcement of the perforated beam. Here, FIG. 1, FIG. 2, FIG. 3 are explanatory diagrams of conventional perforated beam design, and FIG. 1 is a diagram for explaining a bar arrangement state among conventional explanatory diagrams of perforated beam designs. Indicates. FIG. 2 is a diagram for explaining the truss action among the explanatory diagrams of the design of the conventional perforated beam. FIG. 3 is a diagram for explaining the truss action in the vicinity of the hole among the explanatory diagrams of the design of the conventional perforated beam. In Figure 1, H is the diameter of the circular hole (opening) (in the case of a rectangular hole, the diameter of the circumscribed circle), G is the distance between both sides of the stirrups of the hole (reinforcement), y ₀ from wood shaft hole Eccentric distance to the center. In FIG. 2, φ _s represents the inclination of the compressive stress of the concrete above and below the hole, the horizontal arrow represents the adhesion force by the main reinforcement, and the vertical arrow is applied to the concrete by the tensile stress of the lateral reinforcement. Represents the tightening force. Moreover, in FIG. 2, FIG. 3, the part without a hatch shows the area | region where the compressive stress of concrete does not flow. The wider the area without hatches, the greater the compressive force that must be borne in the hatch area around the hole, and the shear reliability of the member decreases due to the compression strength constraints of the concrete. The value obtained by subtracting H / cos φ _s + G tan φ _s from this j _e because the effective distance between main muscle cores on the outermost side of the member is j _e, and the area without hatching is called “effective tr _s action j _ew ”. J _ew is given by _{equation (} 1).

As shown in FIG. 1, the lateral reinforcement on both sides of the hole needs to be applied in the range of (j _ew / 2 + y ₀ ) cotφ _s and is defined as cotφs ≦ 2. It is assumed that the range (2) is sufficient.

The degree of compressive stress σ _cw generated in the concrete in the hatched region is expressed by _Equation 3.

Here, compressive stresses sigma _cw occurring concrete, when equal to the effective compressive strength Nyushiguma _B concrete members shear force acts, since it is νσ _{B =} σ _cw, several terms phi _s 4 is can get.

  The shear reliability strength of a perforated beam reinforced by a normal stirrup is expressed by Equation 5.

Here, in Formula 5, cot φ _s is also included in j _ew , which is complicated as a design formula. Therefore, the Architectural Institute of Japan (conventional technology) uses G = 1.2H and obtains equations (Equation 6, Equation 7, Equation 8) that are approximated by three broken lines, and the minimum value of these three equations is the shear value. It is supposed to give confidence strength. FIG. 4 is a diagram for explaining an accurate solution and an approximate solution of the perforated beam shear reliability strength according to the conventional pointer among the explanatory diagrams of the design of the conventional perforated beam.

Authored by the Architectural Institute of Japan, “Guidelines for Seismic Design of Toughness Guarantees for Reinforced Concrete Buildings and Explanation”, Architectural Institute of Japan, 1999, p. 142-175

In the Architectural Institute guidelines (conventional technology), G (the distance between the lateral reinforcement bars on both sides of the hole (opening)) = 1.2H (diameter of the circular hole), and an equation that approximates three broken lines (Equation 6, Equations (7) and (8) are obtained, and the minimum value of these three equations gives the shear reliability strength. According to the pointer (prior art) of the Architectural Institute, it can be calculated readily shear reliable strength than expression containing cotφ _s. However, there is a concern that the guidelines of the Architectural Institute of Japan (conventional technology) are less accurate than when the shear reliability strength is calculated using an equation including cot φ _s (Equation 5). In addition, the Architectural Institute guidelines (conventional technology) give shear reliability strength on the condition that the required reinforcement range is satisfied for the shear reinforcement of perforated beams. Cannot use academic guidelines. The Architectural Institute guidelines (conventional technology) explain the design method for a single aperture. Therefore, when a plurality of holes are provided, “RC structural calculation standard” (Architecture Society of Japan) such as “the effect of providing a plurality of holes can be ignored by separating the hole core distance by three times or more of the hole diameter”. ) Was customarily designed based on indirect expressions. Therefore, when a plurality of holes are arranged, the degree of freedom in design is lost, for example, the distance between the holes must be increased, although the distance between the holes can be made narrower. There is concern. As described above, the guidelines of the Architectural Institute of Japan have not been able to reasonably evaluate the hole diameter, eccentricity, and distance between the hole cores appropriately.

  In view of the above problems, an object of the present invention is to provide a technique capable of designing a reinforced concrete beam or column having an opening more easily and accurately than in the past.

  In the present invention, in order to solve the above problem, the shear reliability strength is calculated using an approximate angle that approximates the angle of the truss mechanism as the stress transmission mechanism inside the reinforced concrete.

  Specifically, the present invention is a method for designing a reinforced concrete beam or column having a main bar, a reinforcing bar orthogonal to the main bar, and a circular or rectangular opening, and when the opening is circular, If the opening is rectangular, the diameter of the circumscribed circle of the opening, the cover thickness of the opening, the center of the circular opening or the center of the circumscribed circle and the imaginary straight line orthogonal to the main bar and the main bar The distance between the intersection and the virtual straight line and the intersection of the circular opening or the circumscribed circle, the reinforcement arranged farthest from the intersection of the virtual straight line and the main muscle and the intersection of the virtual straight line and the main muscle A shear reliability strength is calculated based on a distance between a bar and an intersection of the main bars, and in the calculation of the shear reliability strength, a truss mechanism as a stress transmission mechanism inside the reinforced concrete, the pressure of the concrete or the main bar Force, and calculates the tensile forces of the main reinforcement, the compressive force in an oblique direction of the concrete, and the shear reliable strength using an approximate angle approximating the angle of the truss mechanism showing a balance of the tensile strength of the reinforcement.

  In the method of designing a reinforced concrete beam or column having an opening according to the present invention, the shear reliability strength is calculated using an approximate angle that approximates the angle of the truss mechanism, so that the diameter of the opening, the cover thickness of the opening, and between each intersection point The shear reliability strength can be easily calculated based on the numerical values that can be grasped from the drawing, such as the distance of. In addition, the calculation accuracy can be improved as compared with the case where the shear reliability strength is calculated based on the guidelines of the Architectural Institute (conventional technology).

  Here, in the calculation of the shear reliability strength, when there are a plurality of openings, the distance between the centers of adjacent circular openings, the distance between the centers of circumscribed circles of adjacent rectangular openings, or the center of the circular opening The shear confidence strength can be calculated further based on the distance between the circumscribed circle center of the rectangular opening adjacent to the circular opening. According to the present invention, the shear reliability strength can be calculated easily and accurately even when a plurality of openings are provided. Further, the distance between the openings can be optimized, and it is not necessary to increase the distance between the openings more than necessary by following the conventional guidelines, and the degree of freedom in design can be improved. Moreover, according to this invention, the diameter of an opening and the distance between openings can be evaluated reasonably appropriately.

  Further, in the calculation of the shear reliability strength, when the opening is eccentric, the shear reliability strength can be calculated further based on the eccentric distance. Thereby, the shear reliability strength can be calculated with higher accuracy. And according to this invention, the diameter of an opening, eccentricity, and the position of an opening can be evaluated reasonably appropriately. The eccentricity can be an eccentricity with respect to the virtual linear reference point. The reference point can be the center of the beam or column member axis.

  Further, in the calculation of the shear reliability strength, when there are a plurality of the openings, or when the openings are eccentric, the target region for calculating the shear reliability strength is classified based on the opening, and the shear reliability strength is determined for each target region. May be calculated. Thereby, the shear reliability strength can be calculated with higher accuracy.

  Here, the present invention can be specified as a design apparatus for a reinforced concrete beam or column having an opening. Specifically, the present invention is a design apparatus for a reinforced concrete beam or column having a main bar, a reinforcing bar perpendicular to the main bar, and a circular or rectangular opening, and the opening is when the opening is circular. If the opening is rectangular, the diameter of the circumscribed circle of the opening, the cover thickness of the opening, the center of the circular opening or the center of the circumscribed circle and the virtual straight line orthogonal to the main bar and the main bar The distance between the intersection of the virtual line and the intersection of the circular opening or the circumscribed circle, the intersection of the virtual line and the main muscle, and the farthest from the intersection of the virtual line and the main muscle A truss mechanism as a stress transmission mechanism inside the reinforced concrete in the calculation of the shear confidence strength, comprising a processing device that calculates the shear confidence strength based on the distance between the reinforcing bar and the intersection of the main reinforcement, Conch Compressive force over preparative or main reinforcement, calculates the tensile forces of the main reinforcement, the compressive force in an oblique direction of the concrete, and the shear reliable strength using an approximate angle approximating the angle of the truss mechanism showing a balance of the tensile strength of the reinforcement.

  An apparatus for designing a reinforced concrete beam or column having an opening can be configured by a general-purpose computer, for example. The design apparatus for a reinforced concrete beam or column having an opening may further include an input device that receives input of information such as the diameter of the opening, and an output device that outputs information and a calculation result by the processing device.

  The present invention can also be specified as a design program for a reinforced concrete beam or column having an opening. Specifically, the present invention is a design program for a reinforced concrete beam or column having a main bar, a reinforcing bar perpendicular to the main bar, and a circular or rectangular opening, and the computer has a circular opening. Is the diameter of the opening, and if the opening is rectangular, the diameter of the circumscribed circle of the opening, the cover thickness of the opening, the center of the circular opening or the center of the circumscribed circle and an imaginary straight line orthogonal to the main bar The distance between the intersection with the main muscle and the intersection between the virtual straight line and the circular opening or the circumscribed circle, the farthest from the intersection between the virtual straight line and the main muscle, and the virtual straight line and the main muscle As a stress transmission mechanism inside the reinforced concrete in the calculation of the shear confidence strength, a step of calculating a shear confidence strength based on a distance between the disposed reinforcing bars and the intersection of the main reinforcing bars is executed. Shear trust using an approximate angle that approximates the angle of the truss mechanism, which balances the compressive force of the concrete or main bar, the tensile force of the main bar, the compressive force of the concrete in the diagonal direction, and the tensile force of the reinforcing bar Calculate the intensity.

  The present invention can also be specified as a recording medium on which the program is recorded. In this case, the function can be provided by causing a computer or the like to read and execute the program of the recording medium. Note that a computer-readable recording medium is a recording medium that accumulates information such as data and programs by electrical, magnetic, optical, mechanical, or chemical action and can be read from a computer or the like. Say.

  ADVANTAGE OF THE INVENTION According to this invention, the technique which can design the reinforced concrete beam or column which has an opening more easily and accurately than before can be provided.

Among the explanatory diagrams of the design of a conventional perforated beam, a diagram for explaining the bar arrangement is shown. The figure explaining truss effect | action among the explanatory drawings of the design of the conventional perforated beam is shown. The figure explaining the truss action in the vicinity of a hole among the explanatory drawings of the design of the conventional perforated beam is shown. Among the explanatory diagrams of the design of the conventional perforated beam, the figure explaining the precise solution and the approximate solution of the perforated beam shear reliability strength by the conventional pointer is shown. 1 shows a reinforced concrete beam according to an embodiment. The structure of the design apparatus of the reinforced concrete beam which concerns on embodiment is shown. The shear reliability strength calculation processing flow according to the embodiment is shown. An example of an input screen is shown. The approximate image figure when calculating angle (phi) s of a truss mechanism is shown. The image figure which calculated the shear reliability strength as angle (phi) _s of a truss mechanism which is different in the upper and lower sides of opening is shown.

  Next, embodiments of the present invention will be described with reference to the drawings. In the following embodiments, a method for designing a reinforced concrete beam having a plurality of openings and the openings being eccentric will be described as an example.

<Embodiment>
<< Structure of reinforced concrete beams >>
FIG. 5 shows a reinforced concrete beam having an opening according to an embodiment. As shown in FIG. 5, the reinforced concrete beam according to the embodiment has a rectangular cross section, a plurality of main bars extending in the axial direction of the beam, a plurality of reinforcing bars arranged to be orthogonal to the main bars, and concrete. A plurality of openings having different diameters are formed in the reinforced concrete. According to the method for designing a reinforced concrete beam according to an embodiment to be described later, the shear reliability strength of reinforced concrete having a plurality of openings as shown in FIG. can do. Details will be described below.

<< Design Equipment Configuration >>
FIG. 6 shows a configuration of a reinforced concrete beam designing apparatus (hereinafter simply referred to as a designing apparatus) according to the embodiment. The design device 1 is configured by a general-purpose computer, and includes a processing device 2 having a CPU 5 (central processing unit) and a memory 6, an input device 3 including a keyboard and a mouse, and a display device 4 including a display. The input device 3 receives input of information such as the diameter of the opening and the cover thickness. The CPU 5 executes a design program for calculating the shear reliability strength stored in the memory, and calculates the shear reliability strength based on information (opening diameter, cover thickness, etc.) input via the input device 3. . The display device 4 displays information and calculation results input via the input device 3. In addition, you may comprise the design apparatus 1 with a tablet terminal and a portable terminal. Further, in the tablet terminal or the mobile terminal, only the information reception and the calculation result display may be performed, and the shear reliability strength may be calculated on a server connected to the tablet terminal or the mobile terminal via the network.

<< Shearing reliability calculation process >>
FIG. 7 shows a processing flow for calculating the shear reliability strength. The calculation process is started when the design program is started. In step 01, the processing device 2 displays an input screen on the display device 4 and accepts input of information necessary for calculating the shear reliability strength. Here, FIG. 8 shows an example of the input screen. In the input screen shown in FIG. 8, an input field is displayed on the left side of the screen, and an image diagram is displayed on the right side of the screen. The unit of the value input in the input field is mm in FIG. The input field shown in FIG. 8 is based on the central opening in the image diagram, and although not shown, the same input field is displayed for each opening. Only the input field may be displayed on the input screen. Alternatively, only the image diagram may be displayed on the input screen so that information can be directly input to the image diagram.

The diameter H of the central opening is the diameter of the central opening in the image diagram. The left opening diameter H _L is the diameter of the left opening in the image diagram. Diameter H _R of the right aperture is the diameter of the right opening of the image view. The cover thickness C of the opening is the distance from the opening to the reinforcing bar. It is preferable that the cover thickness C of the openings is the same. The distance L _L is a horizontal distance from the center of the central opening to the center of the adjacent left opening. The distance _LR is a horizontal distance from the center of the central opening to the center of the adjacent right opening. Eccentric y ₀ is the vertical distance from the reference line to the center of the central aperture. The distance a is defined by the uppermost reinforcing bars arranged at the intersection between the virtual straight line and the upper main reinforcing bar and the reinforcing bars arranged at the left side of the upper possible reinforcing bar. This is the distance between the intersection with the main muscle. The distance b is a distance between the intersection of a virtual straight line that passes through the center of the central opening and is orthogonal to the main muscle and the upper main muscle, and the intersection of the virtual straight line and the central opening. The distance c is the reinforcing bar arranged farthest from the intersection of the virtual straight line and the lower main bar among the reinforcing bars arranged at the intersection between the virtual straight line and the lower main bar and the right bar arrangement range. This is the distance between the intersection with the lower main muscle. The distance d is a distance between the intersection of the virtual straight line and the lower main muscle and the intersection of the virtual straight line and the central opening. When information necessary for calculating the shear reliability strength is input, the process proceeds to step S02.

In step S02, the processing device 2 calculates the shear reliability strength based on the input information. Hereinafter, a negative shearing force (external force is counterclockwise) will be described as an example.

First, the difference in shear reliability between a perforated beam (a beam having an opening) and a non-hole beam (a beam having no opening) as in the embodiment is expressed by Equation 9. The smaller the φ _{s, the} greater the shearing force, but a restriction is defined in the guidelines of the Architectural Institute of Japan, and this embodiment also follows this. When Expression 9 is expanded, it is expressed as Expression 10.

Here, the number 10 contains the cos [phi _s the expression that defines the cotφ _s. Therefore, it is very complicated to obtain cot φ _s from Equation 10. Therefore, the time of obtaining the Cotfai _s is approximated as having 11. A specific approximation method ignores cos φ _s .

  As a result, Expression 10 is expressed as Expression 12.

Here, FIG. 9 shows an image view of approximation when calculating the phi _s. As shown in FIG. 9, in this embodiment, approximate φ _s ′ is used instead of true φ _s . The true φ _s is the angle of the truss mechanism that is also in the guidelines of the conventional architectural society. This original truss mechanism angle φ _s is an angle formed by a straight line corresponding to the main bar and a diagonal line that is farthest from the opening and that contacts the circular opening starting from the intersection of the reinforcing bar and the main bar. On the other hand, the approximate φ _s ′ is the intersection of the straight line corresponding to the main bar, the intersection of the reinforcing bar and the main bar farthest from the opening, and the virtual straight line (vertical virtual line) passing through the center of the circular opening and the opening. The angle between the approximate diagonal line passing through and. Thus, by using approximate φ _s ′ in place of true φ _s , Formula 10 can be uniquely determined as Formula 12.

  Here, in order to simplify Expression 12, it is expressed as Expression 13. Then, each trigonometric function is expressed as in Expression 14.

Here, the compressive stress σ _cw generated in the concrete compression bundle is expressed by an existing formula as shown in Equation 15.

  When the relationship of Equation 16 is established between the effective compressive strength and the compressive stress, Equation 15 is expressed as Equation 17 on the condition that the left and right reinforcing bar ratios are equal. If the left and right reinforcing bar ratios are different, the smaller value can be used for safe design.

  In addition, the shear reliability strength of an effective beam is represented by the existing formula like Formula 18. The reinforcement limit of the reinforcing bar is expressed as in Equation 19.

  Here, when the upper and lower sides of the opening are divided, Expression 18 is expressed as Expression 20. Furthermore, when Expression 20 is simplified based on Expression 13, it is expressed as Expression 21.

The calculation procedure described above is executed in both the positive and negative directions of the shearing force acting on the beam or column, and the minimum value is defined as the shear reliability strength. As shown in Equation 21, by using the approximate angle φ _s ′, the shear reliability strength of the effective beam can be obtained by using the effective width, effective cause, opening diameter, opening cover thickness, distance a, distance b, distance c, Any of the distances d can be calculated from values obtained from the drawing. In addition, the reinforcing bar ratio on both sides of the opening and the reliability strength of the reinforcing bar can be appropriately set according to the type and arrangement of the reinforcing bars to be used. When the shear reliability strength is calculated, the process proceeds to step S03.

  In step S03, the processing device 2 outputs a calculation result. Specifically, the processing device 2 displays the shear reliability strength as a calculation result on the display device 4. Thus, the calculation process of the shear reliability strength is completed.

<Effect>
According to the design method of the beam of reinforced concrete according to the embodiment, by calculating the shear reliable strength using an approximate angle phi _s' that approximates the angle phi _s truss mechanism, the diameter of the opening, the head thickness of the opening, each The shear reliability strength can be easily calculated based on numerical values that can be grasped from the drawing, such as the distance between the intersections. The error due to the approximate angle φ _s ′ is about ± 2%, and it was confirmed that the accuracy was sufficient. This accuracy was confirmed to be higher than the guidelines of the Architectural Institute.

Conventionally, when a plurality of openings are provided, the “RC structural calculation standard” (the Architectural Institute of Japan) such as “the effect of providing a plurality of holes can be ignored by separating the hole core distance by three times or more of the hole diameter”. ) Was customarily designed based on indirect expressions. Therefore, when a plurality of openings are arranged, the degree of freedom in design is lost, for example, the distance between the openings must be increased, although the distance between the openings can be made narrower. There was concern. On the other hand, according to the design method of the reinforced concrete beam according to the embodiment, the diameter of the opening, the cover thickness of the opening, the eccentricity, the distance between the openings, the distances a to d (in other words, the angle φ _{s of the} truss mechanism). The shear reliability strength can be calculated while appropriately changing the values, and these can be rationally evaluated. That is, it is possible to calculate the shear strength after narrowing the interval between the openings as compared to the conventional case, or to calculate the shear strength by appropriately decentering the position of the openings, and the degree of design freedom can be improved.

Furthermore, according to the design method of the reinforced concrete beam according to the embodiment, as shown in FIG. 10, the shear reliability strength can be calculated and evaluated as the angle φ _s of the different truss mechanism above and below the opening. Therefore, the diameter of the openings, the distance between the openings, and the eccentricity can be evaluated more finely, and the degree of freedom in design can be improved.

  The preferred embodiments of the present invention have been described above. However, the method of designing a reinforced concrete beam or column having an opening according to the present invention is not limited thereto, and a combination thereof can be included as much as possible.

  In the embodiment, a reinforced concrete beam has been described as an example. However, the design method according to the embodiment can also be used for a reinforced concrete column having an opening. In the embodiment, a circular opening has been described as an example, but the opening may be rectangular. In this case, the shear reliability strength can be calculated using a circumscribed circle of the rectangular opening instead of the circular opening. In the embodiment, the case where a general-purpose computer is used to execute the design process of the reinforced concrete beam is described as an example. However, the calculation of the shear reliability strength can be performed by a person using a desktop computer, for example.

DESCRIPTION OF SYMBOLS 1 ... Design apparatus 2 ... Processing apparatus 3 ... Input device 4 ... Display apparatus 5 ... CPU
6 ... Memory

Claims (6)

A method of designing a reinforced concrete beam or column having a main bar, a reinforcing bar orthogonal to the main bar, and a circular or rectangular opening,
When the opening is circular, the diameter of the opening, and when the opening is rectangular, the diameter of the circumscribed circle of the opening, the cover thickness of the opening, the center of the circular opening or the center of the circumscribed circle, the main bar The distance between the intersection of the virtual straight line orthogonal to the main muscle and the intersection of the virtual straight line and the circular opening or the circumscribed circle, the intersection of the virtual straight line and the main muscle, the virtual straight line and the main muscle Calculating the shear confidence strength based on the distance between the reinforcing bar arranged farthest from the intersection of the main bar and the intersection of the main bars,
In the calculation of the shear reliability strength, a truss mechanism as a stress transmission mechanism inside the reinforced concrete, which is a compressive force of the concrete or main reinforcement, a tensile strength of the main reinforcement, a compressive force of the concrete in an oblique direction, and a tensile strength of the reinforcing reinforcement. The approximate angle approximated to the angle of the truss mechanism indicating the balance is the diameter of the opening or the circumscribed circle of the opening, the cover thickness of the opening, the intersection of the virtual straight line and the main bar, the virtual straight line and the circular shape. A distance between the opening or the intersection with the circumscribed circle, and an intersection between the virtual straight line and the main muscle, and an intersection between the reinforcing bar and the main muscle that are arranged farthest from the intersection between the virtual straight line and the main muscle. Obtained from the distance between, and calculate the shear confidence strength using the approximate angle ,
Design method for reinforced concrete beams or columns with openings. In the calculation of the shear reliability strength, when there are a plurality of openings, the approximate angle approximate to the angle of the truss mechanism is the diameter of the opening or the diameter of the circumscribed circle of the opening, the cover thickness of the opening, and the virtual straight line. The distance between the intersection with the main muscle and the intersection between the virtual straight line and the circular opening or the circumscribed circle, and the farthest from the intersection between the virtual straight line and the main muscle and the virtual straight line and the main muscle In addition to the distance between the reinforcing bar and the intersection of the main bars, the distance between the centers of adjacent circular openings, the distance between the centers of circumscribed circles of adjacent rectangular openings, or the circular opening A reinforced concrete beam having an opening according to claim 1 , wherein a shear reliability strength is calculated using the approximate angle obtained from a distance between the center of the circle and a circumscribed circle center of a rectangular opening adjacent to the circular opening. Or design method of pillar In the calculation of the shear reliable strength, if the opening is eccentric from the member axis, an opening according to claim 1 or 2 for calculating a further shear trust intensity based on eccentricity from the member axis to the center of the opening Method of designing reinforced concrete beams or columns having Wherein in the calculation of shear reliable strength, if the previous SL opening is eccentric from the member axis, to a region towards the center towards the region and the opening is located the center of the opening of the opening as the reference is not located, the shear The method of designing a beam or column of reinforced concrete having an opening according to any one of claims 1 to 3, wherein a target region for calculating a reliability strength is divided and a shear reliability strength is calculated for each target region. A design device for a reinforced concrete beam or column having a main reinforcing bar, a reinforcing bar orthogonal to the main reinforcing bar, and a circular or rectangular opening,
When the opening is circular, the diameter of the opening, and when the opening is rectangular, the diameter of the circumscribed circle of the opening, the cover thickness of the opening, the center of the circular opening or the center of the circumscribed circle, the main bar The distance between the intersection of the virtual straight line orthogonal to the main muscle and the intersection of the virtual straight line and the circular opening or the circumscribed circle, the intersection of the virtual straight line and the main muscle, the virtual straight line and the main muscle A processing device for calculating the shear reliability based on the distance between the reinforcing bar arranged farthest from the intersection of the main bar and the intersection of the main bars,
In the calculation of the shear reliability strength, a truss mechanism as a stress transmission mechanism inside the reinforced concrete, which is a compressive force of the concrete or main reinforcement, a tensile strength of the main reinforcement, a compressive force of the concrete in an oblique direction, and a tensile strength of the reinforcing reinforcement. The approximate angle approximated to the angle of the truss mechanism indicating the balance is the diameter of the opening or the circumscribed circle of the opening, the cover thickness of the opening, the intersection of the virtual straight line and the main bar, the virtual straight line and the circular shape. A distance between the opening or the intersection with the circumscribed circle, and an intersection between the virtual straight line and the main muscle, and an intersection between the reinforcing bar and the main muscle that are arranged farthest from the intersection between the virtual straight line and the main muscle. Obtained from the distance between, and calculate the shear confidence strength using the approximate angle ,
Design equipment for reinforced concrete beams or columns with openings. A design program for a reinforced concrete beam or column having a main bar, a reinforcing bar perpendicular to the main bar, and a circular or rectangular opening,
On the computer,
When the opening is circular, the diameter of the opening, and when the opening is rectangular, the diameter of the circumscribed circle of the opening, the cover thickness of the opening, the center of the circular opening or the center of the circumscribed circle, the main bar The distance between the intersection of the virtual straight line orthogonal to the main muscle and the intersection of the virtual straight line and the circular opening or the circumscribed circle, the intersection of the virtual straight line and the main muscle, the virtual straight line and the main muscle A step of calculating a shear confidence strength based on a distance between an intersection of the reinforcing bar and the main reinforcing bar arranged farthest from the intersection of
The step of calculating the shear reliability strength is a truss mechanism as a stress transmission mechanism inside the reinforced concrete, wherein the concrete or main bar compressive force, main bar tensile force, diagonal concrete compressive force, and reinforcing bar tensile force The approximate angle approximated to the angle of the truss mechanism showing the balance of force is the diameter of the opening or the diameter of the circumscribed circle of the opening, the cover thickness of the opening, the intersection of the virtual straight line and the main bar, the virtual straight line and the The distance between the circular opening or the intersection with the circumscribed circle, and the intersection between the imaginary straight line and the main muscle, and the reinforcement and the main reinforcement arranged farthest from the intersection between the imaginary straight line and the main reinforcement. Obtained from the distance between the intersections, the shear confidence strength is calculated using the approximate angle ,
Design program for reinforced concrete beams or columns with openings.

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