A method for testing and detecting stiffness of wooden frame shear walls

Abstract

The invention discloses a method for testing and detecting the stiffness of a wood frame shear wall. The shear wall comprises n covering panels. The method comprises the following steps: arbitrarily selecting a covering panel, and obtaining the thickness, area, shear modulus, shear stiffness of the covering panel connected with a wall stud and a group of nails per unit area moment of inertia; based on the parameters of thickness, area, shear modulus, shear stiffness of the covering panel connected with a wall stud and a group of nails per unit area moment of inertia, calculating and obtaining the group of nails rotation stiffness and the covering panel rotation stiffness; calculating the parameters of the group of nails rotation stiffness and the covering panel rotation stiffness, obtaining the comprehensive rotation stiffness of the covering panel, traversing all the covering panels, obtaining n comprehensive rotation stiffnesses; and calculating and obtaining the shear wall stiffness based on the n comprehensive rotation stiffness parameters and a wall height parameter. The invention has the beneficial effects of increasing the calculation accuracy of the shear wall stiffness and improving the efficiency of the shear wall stiffness test.

Description

Technical Field

[0001] The invention relates to the field of shear wall stiffness calculation, and in particular to a wooden frame shear wall stiffness testing method and a detection method. Background Art

[0002] The timber frame shear wall structure is a common structural form of low-rise timber frame buildings. It is composed of a timber frame and a shear wall. The timber frame is connected by mortise and tenon joints or metal parts, and the bending stiffness at the node is small. Therefore, the shear wall is the main lateral force resisting component in low-rise timber frame houses. It is composed of a timber frame, a covering panel and nails.

[0003] At present, there are two methods to determine the stiffness of timber frame shear walls. One is to test the shear wall according to the "Test Method for Static Load and Low-Cycle Repeated Horizontal Loading of Timber Structure Shear Walls" GB / T37745. The other is to look up the table in Appendix N of the "Timber Structure Design Standard" GB50005 to find the wall stiffness value corresponding to the design wall specifications.

[0004] However, when the existing technology tests the stiffness of shear walls, it is usually done manually and compared according to existing rules to determine the stiffness of the wood frame shear walls. When such a test method is used to test the shear walls, the test time is long and the cost is high. In addition, when the test is conducted on different personnel, the test results are inaccurate. In serious cases, the wall structure may become unstable, thus posing certain safety hazards.

[0005] In view of this, this application is hereby filed. Summary of the invention

[0006] The technical problem to be solved by the present invention is that in the prior art, the stiffness of the shear wall is tested and calculated by an operator according to rules, the test time is long, and the test results are inaccurate. The purpose is to provide a wooden frame shear wall stiffness test method and a detection method, which can improve the test efficiency of the shear wall stiffness and increase the accuracy of the shear wall stiffness test.

[0007] The present invention is achieved through the following technical solutions:

[0008] A method for testing the stiffness of a wood frame shear wall, wherein the shear wall comprises n covering panels, and the method steps include:

[0009] S1: Select a cladding panel at random and obtain the thickness, area, shear modulus, shear stiffness of the connection between the cladding panel and the studs, and the moment of inertia per unit area of ​​the nail group;

[0010] S2: Based on the parameters of thickness, area, shear modulus, shear stiffness of the connection between the cladding and the studs, and the moment of inertia per unit area of ​​the nail group, the rotational stiffness of the nail group and the rotational stiffness of the cladding are calculated;

[0011] S3: Calculate the rotational stiffness of the parameter group nails and the rotational stiffness of the covering panel to obtain the comprehensive rotational stiffness of the covering panel, and traverse all the covering panels to obtain n comprehensive rotational stiffnesses;

[0012] S4: Based on n comprehensive rotation stiffness parameters and wall height parameters, the shear wall stiffness is calculated.

[0013] Traditionally, when testing the stiffness of a shear wall, an operator usually tests the stiffness of the shear wall according to relevant specifications. However, when using this method to test the stiffness, it takes a long time and is costly, and different operators may measure different results, resulting in inaccurate test stiffness results. In serious cases, it may bring safety hazards to the constructed wall. The present invention provides a method for testing the stiffness of a wooden frame shear wall. By obtaining parameters of a covering panel and between the covering panel and a group of nails, the parameters are calculated to obtain the shear wall stiffness, thereby increasing the calculation accuracy of the shear wall stiffness and improving the efficiency of the shear wall stiffness test.

[0014] Preferably, in the step S1, the shear modulus is measured by a shearing method of a covering panel.

[0015] Preferably, in step S1, the shear stiffness is measured by a nail detection stiffness method.

[0016] Preferably, the sub-steps of step S2 include:

[0017] The shear stiffness of the connection between the parametric cladding panel and the studs, the moment of inertia per unit area of ​​the nail group, and the cladding panel area are calculated to obtain the rotation stiffness of the nail group.

[0018] The parameters of the cladding panel area, thickness and shear modulus are calculated to obtain the cladding panel rotational stiffness.

[0019] Preferably, the specific expression of the comprehensive rotational stiffness is:

[0020]

[0021] K r is the rotational stiffness, K 板 is the rotational stiffness of the cladding panel, K 钉 is the rotational stiffness of the nail group.

[0022] Preferably, the rotational stiffness K of the cladding panel is 板 The specific expression is:

[0023] K 板 =G B ×t×A w

[0024] G B is the shear modulus of the cladding panel, A w is the area of ​​the covering panel, and t is the thickness of the covering panel.

[0025] Preferably, the group of nails has a rotational stiffness K 钉 The specific expression is:

[0026] K 钉 =I xy ×k×A w

[0027] I xy is the moment of inertia per unit area of ​​the nail group, k is the shear stiffness of the connection between the covering plate and the stud column nails, A w is the area of ​​the cladding panel.

[0028] Preferably, the moment of inertia per unit area of ​​the nail group is xy The specific expression is:

[0029]

[0030] I x =∑(y j -y0) 2 n j

[0031] I y =∑(x i -x0) 2 n i

[0032]

[0033]

[0034] I x is the moment of inertia of the nail column about the neutral axis in the Y direction, I y is the moment of inertia of the nail column about the neutral axis in the X direction, x0 is the coordinate of the neutral axis in the X direction, y0 is the coordinate of the neutral axis in the Y direction, and x i is the X-coordinate of the nail, y j is the Y coordinate of the nail, n i is the number of nails in the X direction, n j is the number of nails in the Y direction.

[0035] Preferably, the specific expression of the shear wall stiffness is:

[0036] K w =∑Kri / H 2

[0037] K ri is the rotational stiffness of each covering panel and the corresponding nail corresponding to the wall, and H is the height of the wall.

[0038] The present invention also discloses a method for detecting the stiffness of a wood frame shear wall, the method comprising the following steps:

[0039] Obtaining the stiffness of the shear wall to be tested, wherein the stiffness is the stiffness of the shear wall obtained by testing using the above-mentioned testing method;

[0040] Based on the shear wall stiffness parameters, the horizontal displacement of the wall top is calculated by using the area distribution method or the stiffness distribution method;

[0041] Calculate the horizontal displacement of the wall top and the wall height to obtain the inter-story displacement angle;

[0042] Determine whether the inter-story displacement angle is less than the displacement angle limit. If so, the stiffness of the shear wall to be tested meets the requirements. Otherwise, adjust the position of the nail group on the shear wall and repeat steps S1 to S4 for the stiffness of the shear wall to be tested until the inter-story displacement angle is less than the displacement angle limit.

[0043] Compared with the prior art, the present invention has the following advantages and beneficial effects:

[0044] The embodiment of the present invention provides a method for testing and detecting the stiffness of a wooden frame shear wall. The method obtains the parameters of a covering panel and between the covering panel and a group of nails, calculates the parameters to obtain the shear wall stiffness, thereby increasing the calculation accuracy of the shear wall stiffness and improving the efficiency of the shear wall stiffness test. BRIEF DESCRIPTION OF THE DRAWINGS

[0045] In order to more clearly illustrate the technical solutions of the exemplary embodiments of the present invention, the drawings required for use in the embodiments will be briefly introduced below. It should be understood that the following drawings only show certain embodiments of the present invention and therefore should not be regarded as limiting the scope. For ordinary technicians in this field, other related drawings can be obtained based on these drawings without paying creative work.

[0046] Figure 1 Schematic diagram of the test method

[0047] Figure 2 Schematic diagram of shear wall structure DETAILED DESCRIPTION

[0048] In order to make the objectives, technical solutions and advantages of the present invention more clearly understood, the present invention is further described in detail below in conjunction with embodiments and drawings. The exemplary embodiments of the present invention and their description are only used to explain the present invention and are not intended to limit the present invention.

[0049] In the following description, a large number of specific details are set forth in order to provide a thorough understanding of the present invention. However, it is apparent to one of ordinary skill in the art that these specific details are not necessarily employed to practice the present invention. In other embodiments, in order to avoid obscuring the present invention, well-known structures, circuits, materials, or methods are not specifically described.

[0050] Throughout the specification, references to "one embodiment," "an embodiment," "an example," or "an example" mean that a particular feature, structure, or characteristic described in conjunction with the embodiment or example is included in at least one embodiment of the present invention. Therefore, the phrases "one embodiment," "an embodiment," "an example," or "an example" appearing in various places throughout the specification do not necessarily all refer to the same embodiment or example. In addition, particular features, structures, or characteristics may be combined in one or more embodiments or examples in any suitable combination and / or sub-combination. In addition, it will be appreciated by those of ordinary skill in the art that the figures provided herein are for illustrative purposes and that the figures are not necessarily drawn to scale. The term "and / or" as used herein includes any and all combinations of one or more of the associated listed items.

[0051] In the description of the present invention, the directions or positional relationships indicated by terms such as “front”, “rear”, “left”, “right”, “up”, “down”, “vertical”, “horizontal”, “high”, “low”, “inside” and “outside” are based on the directions or positional relationships shown in the accompanying drawings and are only for the convenience of describing the present invention and simplifying the description. They do not indicate or imply that the device or element referred to must have a specific direction, be constructed and operated in a specific direction. Therefore, they should not be understood as limiting the scope of protection of the present invention.

[0052] Embodiment 1

[0053] This embodiment discloses a method for testing the stiffness of a wood frame shear wall. Figure 1 As shown, the shear wall includes n covering panels, characterized in that the method steps include:

[0054] S1: Select a cladding panel at random and obtain the thickness, area, shear modulus, shear stiffness of the connection between the cladding panel and the studs, and the moment of inertia per unit area of ​​the nail group;

[0055] In the step S1, the shear modulus is measured by a shearing method for the covering panel, and the shear stiffness is measured by a nail testing stiffness method. In the step S1, the basic dimensions of the covering panel are measured, including the thickness and area of ​​the covering panel.

[0056] S2: Based on the parameters of thickness, area, shear modulus, shear stiffness of the connection between the cladding and the studs, and the moment of inertia per unit area of ​​the nail group, the rotational stiffness of the nail group and the rotational stiffness of the cladding are calculated;

[0057] The sub-steps of step S2 include: calculating the shear stiffness of the connection between the parameter covering panel and the stud nails, the moment of inertia per unit area of ​​the nail group, and the covering panel area to obtain the rotation stiffness of the nail group;

[0058] The parameters of the cladding panel area, thickness and shear modulus are calculated to obtain the cladding panel rotational stiffness.

[0059] S3: Calculate the rotational stiffness of the parameter group nails and the rotational stiffness of the covering panel to obtain the comprehensive rotational stiffness of the covering panel, and traverse all the covering panels to obtain n comprehensive rotational stiffnesses;

[0060] The specific expression of the comprehensive rotational stiffness is:

[0061]

[0062] K r is the rotational stiffness, K 板 is the rotational stiffness of the cladding panel, K 钉 is the rotational stiffness of the nail group.

[0063] The rotational stiffness K of the cladding panel 板 The specific expression is:

[0064] K 板 =G B ×t×A w

[0065] G B is the shear modulus of the cladding panel, A w is the area of ​​the covering panel, and t is the thickness of the covering panel.

[0066] The group of nails rotation stiffness K 钉 The specific expression is:

[0067] K 钉 =I xy ×k×A w

[0068] I xy is the moment of inertia per unit area of ​​the nail group, k is the shear stiffness of the connection between the covering plate and the stud column nails, A wis the area of ​​the cladding panel.

[0069] The moment of inertia per unit area of ​​the nail group is I xy The specific expression is:

[0070]

[0071] I x =∑(y j -y0) 2 n j

[0072] I y =∑(x i -x0) 2 n i

[0073]

[0074]

[0075] I x is the moment of inertia of the nail column about the neutral axis in the Y direction, I y is the moment of inertia of the nail column about the neutral axis in the X direction, x0 is the coordinate of the neutral axis in the X direction, y0 is the coordinate of the neutral axis in the Y direction, and x i is the X-coordinate of the nail, y j is the Y coordinate of the nail, n i is the number of nails in the X direction, n j is the number of nails in the Y direction.

[0076] S4: Based on n comprehensive rotation stiffness parameters and wall height parameters, the shear wall stiffness is calculated.

[0077] The specific expression of the shear wall stiffness is:

[0078] K w =∑K ri / H 2

[0079] K ri is the rotational stiffness of each covering panel and the corresponding nail corresponding to the wall, and H is the height of the wall.

[0080] Implementation process:

[0081] like Figure 2As shown, it is composed of two upper and lower covering panels. The covering panels are made of domestic OSB boards. The covering panels and the wall columns are connected by multiple steel nails 1. The size of the upper covering panel 2 is 1220mm×610mm, and the size of the lower covering panel 3 is 1220mm×2440mm. The nail spacing between the covering panel and the wooden frame is 100mm. The diameter of the steel nail 1 is 2.8mm and the length is 50mm.

[0082] The shear wall stiffness is calculated according to the following steps: the shear stiffness of the nail connection is measured by a nail shear stiffness test, k=480N / mm;

[0083] The thickness of the covering plate is t = 12 mm, and the area of ​​the upper covering plate 2 is A w上 =7442cm 2 , the area A of the lower cover panel 3 w下 =29768cm 2 The shear modulus G of the cladding panel was measured by shear test of the cladding panel. B =588N / mm 2 ;

[0084] Calculate the moment of inertia per unit area of ​​the nail group corresponding to each covering panel I xy :

[0085] First calculate the unit area moment of inertia I of the lower covering panel xy下 : Coordinate of the neutral axis in the X direction Y-axis coordinate of the neutral axis

[0086] The moment of inertia of the nail row about the neutral axis in the Y direction is I x =∑(y j -y0) 2 n j =5.08×10 7 mm 2 ;

[0087] The moment of inertia of the nail row about the neutral axis in the X direction is I y =∑(x i -x0) 2 n i =1.84×10 7 mm 2 ;

[0088] Moment of inertia per unit area of ​​the lower cladding panel

[0089] Similarly, calculate the unit area moment of inertia I of the upper cover panel xy上 =1.53;

[0090] Calculate the corresponding group nail rotation stiffness K of each covering panel 钉 :

[0091] The rotational stiffness K of the lower panel nail group 钉下 =I xy下 ×k×A w下 =6.7×10 9 N·mm;

[0092] The rotational stiffness K of the upper panel nail group 钉上 =I xy上 ×k×A w上 =5.5×10 8 N·mm;

[0093] Calculate the rotational stiffness K of each cladding panel 板 :

[0094] The rotational stiffness K of the lower cladding plate 板下 =G B ×t×A w下 =2.1×10 10 N·mm;

[0095] The rotational stiffness K of the upper cladding plate 板上 =G B ×t×A w上 =5.3×10 9 N·mm;

[0096] Calculate the comprehensive rotational stiffness K of each cladding panel and the corresponding nail group r :

[0097] The combined rotational stiffness of the lower cladding plate and the corresponding nails

[0098] The combined rotational stiffness of the upper cladding plate and the corresponding nails

[0099] Calculate the shear stiffness K of the entire wall w :

[0100] K w =∑K ri / H 2 =K r上 +K r下 / H 2 =599.6N / mm

[0101] The present embodiment discloses a method for testing the stiffness of a wooden frame shear wall. The method obtains the parameters of a covering panel and between the covering panel and a group of nails, calculates the parameters to obtain the shear wall stiffness, thereby increasing the calculation accuracy of the shear wall stiffness and improving the efficiency of the shear wall stiffness test.

[0102] Embodiment 2

[0103] This embodiment discloses a method for detecting stiffness of a wood frame shear wall, the method steps comprising:

[0104] Obtaining the stiffness of the shear wall to be tested, wherein the stiffness is the shear wall stiffness obtained by testing using the testing method in Embodiment 1;

[0105] Based on the shear wall stiffness parameters, the horizontal displacement of the wall top is calculated by using the area distribution method or the stiffness distribution method;

[0106] Calculate the horizontal displacement of the wall top and the wall height to obtain the inter-story displacement angle;

[0107] Determine whether the inter-story displacement angle is less than the displacement angle limit. If so, the stiffness of the shear wall to be tested meets the requirements. Otherwise, adjust the position of the nail group on the shear wall and repeat steps S1 to S4 for the stiffness of the shear wall to be tested until the inter-story displacement angle is less than the displacement angle limit.

[0108] In this embodiment, according to the "Wood Structure Design Standard" GB50005, the horizontal shear force Vw borne by each shear wall is calculated using the area distribution method or the stiffness distribution method, and the horizontal displacement of the wall top Δ = V w / K w ; Determine whether the inter-layer displacement angle Δ / H meets the 1 / 250 displacement angle limit in the "Wood Structure Design Standard" GB50005. If it exceeds the limit, adjust the nail spacing, nail section size or covering panel thickness and repeat steps 1 to 8, and quickly review until it meets the 1 / 250 displacement angle limit, which means that the wood frame shear wall meets the stiffness design requirements.

[0109] A method for detecting the stiffness of a wooden frame shear wall disclosed in this embodiment can continuously adjust the number of nail groups on a designed shear wall, so that the stiffness of the shear wall finally set can ensure a certain degree of stability and increase the stability of the wall constructed by the shear wall.

[0110] The specific implementation methods described above further illustrate the objectives, technical solutions and beneficial effects of the present invention in detail. It should be understood that the above description is only a specific implementation method of the present invention and is not intended to limit the scope of protection of the present invention. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present invention should be included in the scope of protection of the present invention.

Claims

1. A method for testing the stiffness of a timber frame shear wall, wherein the shear wall comprises n cladding panels, characterized in that: The method steps include: S1: Select a cladding panel at random and obtain the thickness, area, shear modulus, shear stiffness of the connection between the cladding panel and the studs, and the moment of inertia per unit area of ​​the nail group; S2: Based on the parameters of thickness, area, shear modulus, shear stiffness of the connection between the cladding and the studs, and the moment of inertia per unit area of ​​the nail group, the rotational stiffness of the nail group and the rotational stiffness of the cladding are calculated; S3: Calculate the rotational stiffness of the parameter group nails and the rotational stiffness of the covering panel to obtain the comprehensive rotational stiffness of the covering panel, and traverse all the covering panels to obtain n comprehensive rotational stiffnesses; S4: Based on n comprehensive rotation stiffness parameters and wall height parameters, the shear wall stiffness is calculated; Specifically, The specific expression of the comprehensive rotational stiffness is: K r is the rotational stiffness, K 板 is the rotational stiffness of the cladding panel, K 钉 is the rotational stiffness of the nail group; The rotational stiffness K of the cladding panel 板 The specific expression is: K 板 =G B ×t×A w G B is the shear modulus of the cladding panel, A w is the area of ​​the covering panel, t is the thickness of the covering panel; The group of nails rotation stiffness K 钉 The specific expression is: K 钉 =I xy ×k×A w I xy is the unit area moment of inertia of the nail group, k is the shear stiffness of the connection between the covering plate and the stud, A w is the area of ​​the cladding panel; The moment of inertia per unit area of ​​the nail group is I xy The specific expression is: I x =∑(y j -y0) 2 n j I y =∑(x i -x0) 2 n i I x is the moment of inertia of the nail column about the neutral axis in the Y direction, I y is the moment of inertia of the nail column about the neutral axis in the X direction, x0 is the coordinate of the neutral axis in the X direction, y0 is the coordinate of the neutral axis in the Y direction, and x i is the X-coordinate of the nail, y j is the Y coordinate of the nail, n i is the number of nails in the X direction, n j is the number of nails in the Y direction; The specific expression of the shear wall stiffness is: Kw=∑K ri / H 2 K ri is the rotational stiffness of each covering panel and the corresponding nail corresponding to the wall, and H is the height of the wall.

2. A method for testing the stiffness of a wood frame shear wall according to claim 1, characterized in that: In the step S1, the shear modulus is measured by a shearing method of a covering panel.

3. A method for testing the stiffness of a wood frame shear wall according to claim 2, characterized in that: In the step S1, the shear stiffness is measured by a nail detection stiffness method.

4. A method for testing the stiffness of a wood frame shear wall according to claim 1, characterized in that: The sub-steps of step S2 include: The shear stiffness of the connection between the parametric cladding panel and the studs, the moment of inertia per unit area of ​​the nail group, and the cladding panel area are calculated to obtain the rotation stiffness of the nail group. The parameters of the cladding panel area, thickness and shear modulus are calculated to obtain the cladding panel rotational stiffness.

5. A method for detecting stiffness of a wood frame shear wall, characterized in that: The method steps include: Obtaining the stiffness of the shear wall to be tested, wherein the stiffness is the stiffness of the shear wall obtained by testing by the testing method according to any one of claims 1 to 4; Based on the shear wall stiffness parameters, the horizontal displacement of the wall top is calculated by using the area distribution method or the stiffness distribution method; Calculate the horizontal displacement of the wall top and the wall height to obtain the inter-story displacement angle; Determine whether the inter-story displacement angle is less than the displacement angle limit. If so, the stiffness of the shear wall to be tested meets the requirements. Otherwise, adjust the position of the nail group on the shear wall and repeat steps S1 to S4 for the stiffness of the shear wall to be tested until the inter-story displacement angle is less than the displacement angle limit.

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