Universal taper conversion joint structure and method of calculating, making and installing same

Abstract

The present application relates to a kind of universal conical conversion joint structures, including steel box girder foundation and tower crane, the steel box girder foundation is provided with the connecting installation site for tower crane installation, the bottom of the tower crane is provided with connecting base, the connecting installation site and the connecting base exist misalignment angle between, it further includes conversion joint, the conversion joint includes joint main body, the joint main body includes with the first connecting end corresponding with the steel box girder foundation, with the second connecting end corresponding with the connecting base, and the cross-sectional area of first connecting end is less than the cross-sectional area of the connecting installation site;The conversion joint is welded on the connecting installation site by the first connecting end, and the second connecting end of the conversion joint after welding is set is mutually matched with the connecting base and is connected.The present application also relates to the calculation method, preparation method and installation method of universal conical conversion joint structure, only need to rotate conversion joint to the tower crane installation direction of construction demand, under the basis of the invariable steel box girder, tower crane installation direction can be adjusted.

Description

Technical Field

[0001] This invention relates to the field of tower crane technology, and in particular to a universal tapered adapter structure and its calculation, preparation and installation methods. Background Technology

[0002] Tower cranes, also known as "tower hoists," are lifting equipment used on construction sites to lift raw materials for construction, such as steel bars, timber, concrete, and steel pipes.

[0003] To ensure the safe operation of tower cranes, reinforced concrete foundations are commonly used. The typical procedure involves pre-embedding fasteners within the reinforced concrete foundation at four points in a square arrangement. Standard sections are anchored into these pre-embedded fasteners, and then stacked one standard section at a time. The standard sections provide compressive and tensile strength, while the reinforced concrete foundation resists punching shear. This technique is advantageous due to its skilled and reliable construction. However, it requires extensive earthwork excavation during concrete pouring and necessitates post-pouring curing of the reinforced concrete foundation. Furthermore, the fasteners are not reusable, and they are prone to misalignment, failing to match the standard tower crane sections. This necessitates disassembly and re-embedding, extending construction time and wasting significant amounts of materials.

[0004] Currently, steel box girder foundations are still used to secure tower cranes, and these foundations are reusable compared to reinforced concrete foundations. However, the standard section used for connecting tower crane foundations on the steel box girder foundation requires specialized design. Furthermore, the original tower crane is designed with a specific installation direction, and the joint fixed to the connection point on the steel box girder foundation can only have one direction. During actual installation, the tower crane's original direction may deviate from the actual installation direction, requiring slight adjustments. However, this cannot be changed once the cross-shaped steel box girder foundation is in place, rendering the original tower crane transition section unusable. Summary of the Invention

[0005] The purpose of this invention is to solve the above-mentioned technical problems and provide a universal tapered adapter structure. The cross-sectional area of ​​the second connecting end of this universal tapered adapter structure is larger than that of the first connecting end, creating an area difference. The second connecting end connects to the connecting base of the tower crane foundation, while the first connecting end connects to the connecting installation position of the steel box girder foundation. When the universal tapered adapter structure rotates to the installation direction required by the connecting base of the tower crane foundation, i.e., the installation direction of the tower crane, because the area of ​​the first connecting end is relatively small and smaller than the connecting installation position on the steel box girder foundation, it has sufficient space to rotate to fit and weld with the connecting installation position of the steel box girder foundation, without causing issues with the tower crane connecting base. When there is a misalignment angle between the first connecting end and the steel box girder connecting installation position, there is a problem that the first connecting end cannot be properly connected or welded to the steel box girder connecting installation position. Moreover, the universal tapered conversion joint structure can be reused. When similar tower cranes need to be installed in other places, if the original tower crane installation angle meets the requirements, it can continue to be used. If it does not meet the requirements, the first connecting end will be welded and cut at the connecting installation position on the steel box girder foundation, the connection between the second connecting end and the connecting base will be disassembled, and then the tapered conversion joint structure will be rotated to meet the angle required by the actual construction situation, and then welded and tightened. This saves the materials and costs of manufacturing new joints, reduces the need to recalculate the various parameters of the joints, and ensures the safety of construction.

[0006] The present invention adopts the following technical solution:

[0007] A universal tapered conversion joint structure includes a steel box girder foundation and a tower crane. The steel box girder foundation is provided with a connection mounting position for the tower crane to install. The bottom end of the tower crane is provided with a connecting base. There is a misalignment angle between the connection mounting position and the connecting base. The structure is characterized by further including a conversion joint. The conversion joint includes a joint body. The joint body includes a first connecting end corresponding to the steel box girder foundation and a second connecting end corresponding to the connecting base. The cross-sectional area of ​​the first connecting end is smaller than the cross-sectional area of ​​the connection mounting position.

[0008] The adapter is welded to the connection mounting position via the first connection end, and the second connection end of the adapter after welding is matched and connected to the connection base.

[0009] Preferably, the second connecting end includes a connecting panel, and the connecting panel and the connecting base are provided with corresponding mounting holes, and fasteners are detachably installed on the mounting holes.

[0010] Preferably, the diameter of the connecting panel is greater than the diameter of the connector body, and the connecting panel and the connector body are centrally overlapped.

[0011] It also includes several reinforcing ribs, which are arranged in right-angled triangles or right-angled trapezoids. One right-angled side of the reinforcing rib is welded to the outer side of the connector body, and the other right-angled side of the reinforcing rib is welded to the bottom side of the connecting panel.

[0012] Preferably, a plurality of the reinforcing ribs are evenly arranged around the centerline of the joint body, and the mounting holes are provided between two adjacent reinforcing ribs.

[0013] Preferably, the joint body is formed by welding several vertical steel plates end to end to form a hollow structure, or the joint body is formed by bending steel plate structures and then welding them end to end to form a hollow structure.

[0014] In another embodiment, the steel box girder foundation includes a first steel box girder and a second steel box girder intersecting the first steel box girder. The sides of the first steel box girder and / or the second steel box girder are also provided with reinforcing steel plates corresponding to the reinforcing ribs. One side of the reinforcing steel plate is welded and fixed to the steel box girder foundation, and the top end face of the reinforcing steel plate is welded and connected to the bottom end of the reinforcing rib.

[0015] The present invention also provides a calculation method for the universal tapered transition joint structure described herein, the specific steps of which are as follows:

[0016] Step 1) Based on the tower crane model, consult the tower crane instruction manual to determine the following values ​​for the standard section width B, the standard bending moment MK, the standard torque MZ, the standard vertical load FK, the standard horizontal shear force VK, and the width B2 of the connecting base steel plate of the standard section of the tower crane under working and non-working conditions.

[0017] Step 2) Lay out the foundation for the tower crane steel box girder. The specific layout needs to be determined according to the construction requirements.

[0018] Step 3) Arrange the location of the tower crane universal conversion tapered joint according to the actual conditions of the construction site;

[0019] Step 4) Assuming the dimensions of the steel plate for the universal conversion tapered joint structure, perform verification calculations. The verification steps are shown in the following formula. If the verification is successful, assume the dimensions are acceptable; otherwise, thicken the steel plate. Where:

[0020] 1) Based on the combination formula of basic load effects in the "Code for Design of Building Structures" GB50009, convert the standard values ​​into design values:

[0021] Where FK is the standard value of vertical load in the tower crane's instruction manual, which is a permanent load, and the partial factor for permanent loads is taken as 1.3; MK is the standard value of bending moment of the tower crane, MZ is the standard value of torque of the tower crane, and VK is the standard value of horizontal shear force of the tower crane. MK, MZ, and VK are variable loads, and the combination factor for variable loads is taken as 1.5.

[0022] 2) Using the calculation formula for the eccentric vertical force of a single pile in a pile group foundation as specified in the "Code for Design of Building Foundations" GB50007, the design values ​​of the universal conversion tapered joint structure under both working and non-working conditions were calculated, totaling eight values. The largest value was taken as Fmax. The calculation formula is as follows:

[0023] (Equation 1)

[0024] in,

[0025] (Equation 2)

[0026] The height of the tower crane steel box girder is the same as the height of the first and second steel box girder cross-sections.

[0027] 3) Calculate the force V along the X-axis respectively. 1max Force V along the Y-axis 2max The calculation formula is as follows:

[0028] (Equation 3)

[0029] (Equation 4)

[0030] in,

[0031] Force is transmitted along axes X1 and Y1.

[0032] V1max is the maximum design value converted from the standard value in the tower crane instruction manual, and V2max is the horizontal shear force converted from the tower crane torque, with V1max being horizontally perpendicular to V2max.

[0033] 4) Calculate the bending strength of the vertical steel plate (calculation of the bending strength of vertical steel plate 501a and the first weld 510);

[0034] According to mechanics of materials, the moment of inertia I of the planar portion enclosed by the vertical steel plate is calculated using the following formula:

[0035] (Equation 5)

[0036] Wherein, t1: thickness of the vertical steel plate; t2: thickness of the reinforcing rib; B1: width of the joint body; B2: width of the connecting panel;

[0037] Based on Equation 5 and mechanics of materials, calculate the section modulus:

[0038] (Equation 6);

[0039] Where B: the width of a standard section of the tower crane.

[0040] Calculate the cross-sectional area: (Equation 7)

[0041] The strength of the weld and steel plate is calculated based on the calculated cross-sectional area and section modulus W obtained above.

[0042] (Equation 8)

[0043] in,

[0044] h1: Steel plate thickness of the connecting base of the tower crane standard section; h2: Steel plate thickness of the connecting panel of the universal tapered adapter; h3: Overall height of the universal tapered adapter body;

[0045] By consulting the steel structure handbook, we obtained the steel plate strength grade and the corresponding design strength 1 for the steel plate thickness, as well as the design value 2 for the bending strength of equal-strength welded steel plates, and the design value 3 for the shear strength of equal-strength welded steel plates.

[0046] When the bending strength calculated by formula 8 is less than the design strength 1 of the steel plate and the design bending strength 2 of the weld of equal strength, then the above dimensions are valid.

[0047] When the bending strength calculated by formula 8 is greater than the design strength 1 of the steel plate and the design bending strength 2 of the equal strength weld, it is necessary to increase the width B1 of the joint body, or increase the thickness t1 of the vertical steel plate, or decrease the overall height h3 of the universal tapered conversion joint; then repeat the above calculation until the bending strength calculated by formula 8 is less than the design strength 1 of the steel plate and the design bending strength 2 of the equal strength weld.

[0048] 5) Calculate the shear strength of the vertical steel plate (calculation of vertical steel plate components and calculation of the shear strength of the first weld).

[0049] According to the theory of material strength:

[0050] (Equation 9)

[0051] If the shear strength calculated by formula 9 is less than the design strength of the equal-strength shear strength 3, then the above calculation meets the requirements;

[0052] If the shear strength calculated by formula 9 is greater than the shear strength design value of 3, then the width B1 of the joint body needs to be increased, or the thickness t1 of the vertical steel plate needs to be increased; then repeat the above calculation steps 2)-5) until the shear strength calculated by formula 9 is less than the shear strength design value of 3.

[0053] 6) Calculation of steel plate connecting bolts (505)

[0054] (i) Assuming the opening area of ​​the joint mounting hole is A1, if the size of the connecting bolt is the same as that of the connecting base of the tower crane standard section, and the thickness of the connecting panel h2 is greater than the thickness of the connecting base of the tower crane standard section h1, then the shear strength of the mounting hole of the connecting base of the tower crane standard section does not need to be calculated.

[0055] (ii) Let the opening area of ​​the joint bolt be A2, the shear design strength of the joint bolt be V1, and the compressive design strength be V2;

[0056] Based on the minimum values ​​of the compressive strength and shear strength of the high-strength bolts, the smaller value is taken as FF1;

[0057] The bending moment MF1 is calculated using the following formula:

[0058] (Equation 10); (Equation 11);

[0059] The flexural strengths F1 and F2 are calculated using the following formulas:

[0060] (Equation 12); (Equation 13)

[0061] Wherein, W1 and W2 are the section modulus of the connecting panel formed by two adjacent second welds;

[0062] The calculation method for the section modulus (W1, W2) of the connecting panel enclosed by two adjacent second welds (511) shall be implemented with reference to formulas 5 and 6;

[0063] If the results of formulas 12 and 13 are less than or equal to the design strength of the steel plate 1, then the above calculation meets the requirements; otherwise, the thickness h1 of the connecting base of the tower crane standard section should be increased.

[0064] 7) The steel selection and welding method for the second and third welds are the same as those for the first weld.

[0065] 8) If all the above calculations are completed, the modeling is valid.

[0066] This application also provides a method for preparing the universal tapered adapter described in this application, the specific steps of which are as follows:

[0067] 1) Select a suitable steel plate based on the calculated parameters;

[0068] 2) Based on the calculated parameters, the steel plate is cut using the acetylene-oxygen cutting method to cut out the universal tapered adapter body, connecting panel, and reinforcing ribs. Then, a steel plate drilling machine is used to drill holes in the connecting panel to form the adapter mounting holes. The cut universal tapered adapter body, connecting panel, and reinforcing ribs are then ground using a steel plate grinding machine. After each universal tapered adapter body, connecting panel, and reinforcing rib is processed, the universal tapered adapter body, connecting panel, and reinforcing rib are assembled together using welding rods and welding machine, and then welded together using a welding machine.

[0069] This application also provides a method for installing the universal tapered adapter described in this application, the specific steps of which are as follows:

[0070] 1) Rotate the universal tapered adapter to match the required installation angle between the universal tapered adapter and the connection base of the tower crane foundation;

[0071] 2) After rotation, if the reinforcing rib does not extend beyond the connection and installation position of the steel box girder, the first connection end of the universal tapered conversion joint body is welded to the connection and installation position, and the weld is calculated according to the formula requirements shown; if the reinforcing rib extends beyond the connection and installation position after rotation, a reinforcing steel plate is welded to the side of the first steel box girder and / or the second steel box girder at the location corresponding to the reinforcing rib.

[0072] 3) Insert the vertical support rod of the standard tower crane section into the connecting panel, and use fasteners to connect and secure the connecting base of the tower crane to the connecting panel. Tighten the fasteners with a torque wrench according to the torque requirements.

[0073] Compared with the prior art, the beneficial effects of the present invention are as follows:

[0074] By adopting the above solution, the tower crane installation direction can be easily matched with the actual construction requirements through a simple rotating universal tapered adapter. This avoids the problem of the tower crane's design and installation direction deviating from the actual installation direction due to the adapter's setting not meeting the actual construction requirements, resulting in a mismatch between the steel box girder foundation and the adapter, and consequently, the tower crane's inability to be matched with the steel box girder foundation. Furthermore, when it is necessary to change the tower crane foundation in other locations, if the original tower crane installation angle meets the requirements, it can continue to be used; if not, the first connection end on the steel box girder foundation is welded and cut, the connection between the second connection end and the connecting base is disassembled, and then the tapered adapter structure is rotated to meet the angle required by the actual construction situation, and then welded and tightened. The installation is simple, thus saving the materials and costs of manufacturing new joints, reducing the need to recalculate the joint parameters, and ensuring construction safety. Attached Figure Description

[0075] Figure 1 A top view of the foundation layout for the tower crane's steel box girder;

[0076] Figure 2 According to Figure 1 Enlarged schematic diagram of the arrangement of universal tapered transition joints on the steel box girder foundation;

[0077] Figure 3 This is a force analysis diagram of a universal tapered adapter joint;

[0078] Figure 4 According to Figure 3 Another force analysis diagram of the universal tapered adapter joint;

[0079] Figure 5 Schematic diagram of the first connection end of the universal tapered adapter. Figure 1 ;

[0080] Figure 6 Schematic diagram of the first connection end of the universal tapered adapter. Figure 2 ;

[0081] Figure 7 Schematic diagram of the first connection end of the universal tapered adapter. Figure 3 ;

[0082] Figure 8 Schematic diagram of the second connection end of the universal tapered adapter. Figure 1 ;

[0083] Figure 9 Schematic diagram of the second connection end of the universal tapered adapter. Figure 2 ;

[0084] Figure 10 for Figure 4 Enlarged view of the universal tapered joint at point 5 (circled);

[0085] Figure 11 The diagram shows the relationship between the forces V1max and V2max of the universal tapered adapter joint.

[0086] Figure 12 This is a partial enlarged view of the conversion joint 5 and the welding machine part of the steel box girder foundation, according to another embodiment.

[0087] Figure label:

[0088] 1-First steel box girder; 11-First steel box girder connection and installation position; 2-Second steel box girder; 21-Second steel box girder connection and installation position; 3-Surrounding structure; 4-Tower crane; 41-Connecting base; 411-Base mounting hole; 42-Vertical support rod of tower crane standard section; 5-Conversion joint; 51-First conversion joint; 52-Second conversion joint; 53-Third conversion joint; 54-Fourth conversion joint; 501-Joint body; 502-First connecting end; 503-Vertical steel plate; 504-Reinforcing rib; 505-Second connecting end; 506-Connecting panel; 507-Joint mounting hole; 508-Steel plate connecting bolt; 509-Supporting reinforcing bar; 510-First weld, connecting weld between vertical steel plate and first and second connecting ends; 511-Second weld, weld between reinforcing rib and first connecting end; 512-Third weld, weld between reinforcing rib and second connecting end; 6-Reinforcing steel plate; 7-Reinforcing connecting weld. Detailed Implementation

[0089] To facilitate understanding of the present invention, a detailed description of the present invention will be provided below with reference to the accompanying drawings. The drawings show preferred embodiments of the present invention and should not be construed as limiting the scope of protection of the present invention. This application can be embodied in many different forms, and those skilled in the art can make some non-essential modifications, improvements, and adjustments to the present invention based on the above description.

[0090] It should be noted that all directional indications in the embodiments of the present invention, such as up, down, left, right, front, and back, are only used to explain the corresponding positional relationship and movement of each component in a specific posture (as shown in the attached figure). If the specific posture changes, the directional indication will also change accordingly.

[0091] Furthermore, the use of terms such as "first," "second," etc., in this invention is for descriptive purposes only and should not be construed as implying or indicating relative importance or implicitly specifying the number of technical features shown. Thus, a feature defined with "first" or "second" may explicitly or implicitly include at least one of those features. For example, the first adapter 51, second adapter 52, third adapter 53, and fourth adapter 54 referred to herein all refer to adapter 5 in this application.

[0092] This invention provides a universal tapered transition joint structure, including a steel box girder foundation and a tower crane 4. A connection mounting position for the tower crane is provided on the steel box girder foundation. A connecting base 41 is provided at the bottom of the tower crane. There is a misalignment angle between the connection mounting position and the connecting base 41. Figure 1The tower crane steel box girder foundation is arranged as a cross steel box girder foundation, including a first steel box girder 1, a second steel box girder 2 perpendicular to the first steel box girder 1, and a surrounding structure 3. The first steel box girder 1 and the second steel box girder 2 are provided with a first steel box girder connection installation position 11 and a second steel box girder connection installation position 21. In the actual construction site environment, the steel box girder foundation layout can be adjusted according to construction needs.

[0093] It also includes adapter 5, for example Figure 1-2 The first, second, third, and fourth conversion joints 51, 52, 53, and 54 shown are provided. Each conversion joint 5 includes a joint body 501. The joint body 501 includes a first connecting end 502 corresponding to the first steel box girder connection installation position 11 or the second steel box girder connection installation position 21, and a second connecting end 505 corresponding to the connecting base 41. The cross-sectional area of ​​the first connecting end 502 is smaller than the cross-sectional area of ​​the first steel box girder connection installation position 11 and the second steel box girder connection installation position 21.

[0094] The adapter 5 is welded to the connection mounting position via the first connection end 502, for example... Figure 1 The first adapter 51 and the fourth adapter 54 shown are respectively installed on the first steel box girder connection installation position 11, and the second adapter 52 and the third adapter 53 are respectively installed on the second steel box girder connection installation position 21; and the second connection end 502 of the adapter 5 after welding is matched and connected to the connection base 41.

[0095] The structure of the connector body 501 will be further described below. The second connecting end 505 of the universal tapered adapter structure includes a connecting panel 506. The connecting panel 506 has connector mounting holes 507, which correspond one-to-one with the base mounting holes 411 on the connecting base 41. Fasteners, such as steel plate connecting bolts 508 and nuts (not shown), are detachably installed on the connector mounting holes 507 and the base mounting holes 411. The steel plate connecting bolts 508 are inserted one-to-one into the base mounting holes 411 and the connector mounting holes 507, and the nuts are tightened using a torque wrench. This effectively secures the tower crane's connecting base 41 and the connecting panel 506, thus securing the tower crane 4 and the second connecting end 505.

[0096] Further analysis, such as Figure 5-10As shown, the diameter-width value of the connection panel 506 is B2, and the diameter-width value of the joint body 501 is B1. The diameter-width value B2 of the connection panel 506 is greater than the diameter-width value B1 of the joint body 501, and the connection panel 506 and the joint body 501 are arranged with their centers coinciding. The joint body 501 further includes a number of reinforcing ribs 504, and a number of the reinforcing ribs are arranged in a right triangle or a right trapezoid. One right side of the reinforcing rib is welded to the outer side of the joint body 501, and the other right side of the reinforcing rib is welded to the bottom side of the connection panel 506. In a preferred embodiment, as Figure 11-12 , the reinforcing rib is a right trapezoid. Therefore, an inverted conical structure is formed. Thus, a structure with a generally triangular cross-section is formed by the joint body 501, the first connection end 502, and the second connection end 505, improving the working stability and safety of the universal conical adapter structure. And the smaller cross-section of the first connection end 502 provides more possible angles for the rotation of the entire universal conical adapter structure, so that when the installation angle of the tower crane needs to be slightly adjusted, a large rotation radian of the first connection end 502 will not affect the connection between the second connection end 505 and the connection base 41 of the tower crane.

[0097] The reinforcing ribs 504 are uniformly arranged around the center line of the joint body 501. Therefore, a "rice" shape is presented on the bottom side of the connection panel 506, as Figure 8-9 , ensuring that the joint body 501 can obtain sufficient rigid support on each side. And a joint installation hole 507 is provided between two adjacent reinforcing ribs 504 to facilitate fastening corresponding to the base installation hole 411 of the tower crane connection base 41 one by one.

[0098] Figure 5-7 The structure of the joint body 501 is further analyzed. From Figure 5-7 it can be seen that the joint body 501 is formed by welding a number of vertical steel plates 503 end to end to form a hollow structural member; or, the joint body 501 is formed by bending a steel plate structural member and then welding the ends to form a hollow structural member. Such a setting ensures that the inner side of the joint body 501 is relatively flat, facilitating the anchoring of the universal conical adapter by the vertical support rod of the tower crane standard section, which is beneficial to the installation of the tower crane foundation.

[0099] In a preferred embodiment, a support steel bar 509 is also provided in the universal conical adapter, as Figure 5-7 shown, which is used to assist in positioning the installation of the tower crane base. When calculating the force analysis, the support steel bar 509 is not considered.

[0100] In another embodiment, as Figure 12As shown, under the cross-shaped steel box girder foundation, in order to meet construction requirements, after rotating the universal tapered transition joint structure, a portion of the reinforcing rib 504 is set outside the steel box girder foundation. At this time, reinforcing steel plates 6 need to be set on the side of the first steel box girder 1 and / or the second steel box girder 2 corresponding to the reinforcing rib. One side of the reinforcing steel plate is welded to a steel box girder 1 and / or the second steel box girder 2. The top end face of the reinforcing steel plate 6 is welded to the bottom end of the reinforcing rib 504 to form a reinforcing weld seam 7. This ensures that the part of the bottom of the reinforcing rib that was not rigidly supported after rotation is fully supported, and that the transmission of vertical loads will not cause structural deformation of the universal tapered transition joint.

[0101] The selection of steel plates for the above structure needs to be determined by the parameters calculated below, because joints in the steel box girder foundation of the steel structure foundation require special calculation. The specific steps for calculating the above universal joint tapered connector structure are as follows:

[0102] Step 1) Based on the tower crane model, consult the tower crane instruction manual to determine the following values ​​for the standard section width B, the standard bending moment MK, the standard torque MZ, the standard vertical load FK, the standard horizontal shear force VK, and the width B2 of the connecting base steel plate of the standard section of the tower crane under working and non-working conditions.

[0103] Step 2) Arrange the foundation for the tower crane steel box girder, such as... Figure 1 As shown, the foundation is arranged as a cross-shaped steel box girder, in which the first steel box girder 1 and the second steel box girder 2 are intersected, but the specific arrangement needs to be determined according to the construction requirements.

[0104] Step 3) Based on the actual conditions of the construction site, arrange the connection and installation positions 11 and 21 of the tower crane universal conversion tapered joints 51, 52, 53, and 54 on the first and second steel box girders 1 and 2, as follows: Figure 2 As shown;

[0105] Step 4) Assuming the dimensions of the universal tapered connector 5 steel plate, perform verification calculations. The verification steps are shown in the following formula. If the verification is successful, assume the dimensions are acceptable; otherwise, thicken the steel plate. Where:

[0106] 1) Based on the combination formula of basic load effects in the "Code for Design of Building Structures" GB50009, convert the standard values ​​into design values:

[0107] Wherein, FK is the standard value of vertical load in the tower crane instruction manual, which is a permanent load, and the partial factor for permanent load is 1.3; MK is the standard value of bending moment of tower crane, MZ is the standard value of torque of tower crane, VK is the standard value of horizontal shear force of tower crane, MK, MZ and VK are variable loads, and the combination factor for variable load is 1.5.

[0108] Using the calculation formula for the eccentric vertical force of a single pile in a pile group foundation from the "Code for Design of Building Foundations" GB50007, the design values ​​of universal joint tapered joints 51, 52, 53, and 54 were calculated under both working and non-working conditions, for a total of eight values. Figure 3 The stress conditions of the universal tapered joints 51, 52, 53, and 54 are shown. The largest value among them is taken as Fmax. The calculation formula is as follows:

[0109] (Equation 1)

[0110] in,

[0111] (Equation 2)

[0112] The height of the tower crane steel box girder is Figure 1 The height of the cross-sections of the first and second steel box girders are known conditions.

[0113] 2) Calculate the force V along the X-axis. 1max Force V along the Y-axis 2max The calculation formula is as follows:

[0114] (Equation 3)

[0115] 3) Calculate the force V along the Y-axis. 2max The calculation formula is as follows:

[0116] (Equation 4)

[0117] in,

[0118] Although the force calculated along the X-axis generally has an angle with the X1-axis, and the force calculated along the Y-axis generally has an angle with the Y1-axis, the force is smaller after considering the projection. To simplify the calculation and increase the safety margin, it is assumed that the transmitted force is along the X1 and Y1 axes. V1max is the maximum value of the design value converted from the standard value in the tower crane manual, and V2max is the horizontal shear force converted from the tower crane torque. V1max is horizontally perpendicular to V2max.

[0119] 4) Calculate the bending strength of the vertical steel plate 503 (calculation of the bending strength of the vertical steel plate 503 and the first weld 510).

[0120] According to mechanics of materials, the moment of inertia I of the planar portion enclosed by the vertical steel plate 503 is calculated using the following formula:

[0121] (Equation 5)

[0122] Wherein, t1: thickness of vertical steel plate 503; t2: thickness of reinforcing rib 504; B1: width of joint body 501; B2: width of connecting panel 506;

[0123] Based on Equation 5 and mechanics of materials, calculate the section modulus:

[0124] (Equation 6);

[0125] Where B: the width of a standard section of the tower crane.

[0126] Calculate the cross-sectional area: (Equation 7)

[0127] The strength of the weld and steel plate is calculated based on the calculated cross-sectional area and section modulus W obtained above.

[0128] (Equation 8)

[0129] in,

[0130] h1: Thickness of 41 steel plate for the connecting base of the tower crane standard section; h2: Thickness of 506 steel plate for the connecting panel of the universal tapered adapter; h3: Overall height of the universal tapered adapter;

[0131] By consulting relevant steel structure manuals, we obtained the steel plate strength grade and the corresponding design strength 1 for the steel plate thickness, as well as the design bending strength 2 and the design shear strength 3 for equal-strength welding.

[0132] When the bending strength calculated by formula 8 is less than the design strength 1 of the steel plate and the design bending strength 2 of the weld of equal strength, then the above dimensions are valid.

[0133] If the bending strength calculated by formula 8 is greater than the design strength 1 of the steel plate and the design bending strength 2 of the welded steel plate of equal strength, then it is necessary to increase the width B1 of the base, or increase the thickness t1 of the vertical steel plate 503, or decrease the overall height h3 of the universal tapered adapter. Then repeat the above calculation until the bending strength calculated by formula 8 is less than the design strength 1 of the steel plate and the design bending strength 2 of the welded steel plate of equal strength.

[0134] 5) Calculate the shear strength of the vertical steel plate (calculation of vertical steel plate 503 component and calculation of shear strength of the first connecting weld 510).

[0135] According to the theory of material strength:

[0136] (Equation 9)

[0137] If the shear strength calculated by formula 9 is less than the design strength of the equal-strength shear strength 3, then the above calculation meets the requirements;

[0138] If the shear strength calculated by formula 9 is greater than the equivalent shear design strength 3, then the width B1 of the joint body 501 needs to be increased, or the thickness t1 of the vertical steel plate 503 needs to be increased. Then repeat the above calculation steps until the shear strength calculated by formula 9 is less than the equivalent shear design strength 3. This is because the shear strength of the weld in the steel plate is always less than or equal to the shear strength of the steel plate. Therefore, if the weld meets the requirements, the steel plate strength is satisfied.

[0139] 6) Calculation of 508 steel plate connecting bolts

[0140] (i) Assuming the opening area of ​​the joint mounting hole 507 is A1 (the same as the opening area of ​​the base mounting hole 411 of the tower crane standard section), if the size of the steel plate connecting bolt 508 component is the same as that of the base of the tower crane standard section, and the thickness h2 of the steel plate of the connecting panel 506 is greater than the thickness h1 of the steel plate of the connecting base 41 of the tower crane standard section, then the shear strength of the mounting hole of the connecting base 41 of the tower crane standard section does not need to be calculated.

[0141] (ii) Let the opening area of ​​the connecting bolt 508 be A2, the shear design strength of the joint bolt be V1, and the extrusion design strength be V2;

[0142] Based on the comparison of the minimum values ​​of the extrusion strength and shear strength of high-strength bolts (generally shear strength is smaller), the smaller value is taken as FF1;

[0143] The bending moment MF1 is calculated using the following formula:

[0144] (Equation 10); (Equation 11);

[0145] The flexural strengths F1 and F2 are calculated using the following formulas:

[0146] (Equation 12); (Equation 13)

[0147] Wherein, W1 and W2 are the section modulus of the connecting panel 506 enclosed by two adjacent second welds 511 (specific enclosed area shown in the diagram). Figure 9 );

[0148] The calculation method for the section modulus (W1, W2) of the connecting panel 506 formed by two adjacent second welds 511 is implemented with reference to formulas 5 and 6.

[0149] If the results of formulas 12 and 13 are less than or equal to the design strength 1 of the steel plate, then the above calculation meets the requirements; otherwise, the thickness h1 of the connecting base 506 of the tower crane standard section should be increased.

[0150] 7) The steel selection and welding method for the second weld 511 and the third weld 512 are the same as those for the first weld 510 above.

[0151] 8) If all the above calculations are completed, the modeling is valid.

[0152] Based on the above calculations, the forming process of a universal conversion tapered joint structure based on the above-mentioned steel structure tower crane foundation includes the following steps:

[0153] 1) Select a suitable steel plate based on the parameters calculated above;

[0154] 2) Based on the calculated parameters, the universal tapered adapter body 501, connecting panel 506, and reinforcing rib 504 are cut using the acetylene-oxygen cutting method. Then, a steel plate drilling machine is used to drill holes in the connecting panel 506 to form the adapter mounting holes 507. A steel plate grinding machine is then used to grind the cut universal tapered adapter body 501, connecting panel 506, and reinforcing rib 504. After the processing of each universal tapered adapter body, connecting panel, and reinforcing rib is completed, the universal tapered adapter body, connecting panel, and reinforcing rib are assembled together using welding rods and a welding machine, and then welded. The specific weld seams can be seen in the image. Figures 5-9 ;

[0155] Welding quality requirements: The weld strength is equal to that of a butt joint, or the butt weld grade is Grade I or II.

[0156] Once all universal tapered adapter joints are machined, they will be installed.

[0157] An installation method based on the above-mentioned universal tapered adapter structure includes the following specific steps:

[0158] 1) Rotate the adapter 5 by an angle so that the second connection end 505 of the universal tapered adapter matches the required installation angle of the connection base 41 of the tower crane foundation;

[0159] 2) After rotation, if the reinforcing rib 504 does not extend beyond the first and second steel box girder connection installation positions 11 and 21, then the first connecting end 502 of the universal tapered conversion joint body is welded to the first and second steel box girder connection installation positions 11 and 21, and the weld is calculated according to the formula shown above; if the reinforcing rib extends beyond the first and second steel box girder connection installation positions 11 and 21 after rotation, then a reinforcing steel plate 6 is welded to the side of the first steel box girder and / or the second steel box girder corresponding to the reinforcing rib, and the welded reinforcing connection weld also needs to be calculated according to the formula shown above.

[0160] 3) Insert the vertical support rod 42 of the tower crane standard section into the connecting panel 506, and use fasteners to connect and secure the connecting base 41 of the tower crane to the connecting panel 506. Tighten the fasteners with a torque wrench according to the torque requirements.

[0161] The above installation method allows for omnidirectional adjustment of the tower crane foundation installation direction without altering the steel box girder foundation. This makes it easy to match the tower crane foundation with the steel box girder foundation, avoiding the waste and time of having to dismantle the pre-designed tower crane foundation and remake it when the installation position deviates from the design position.

[0162] Therefore, when tower crane foundations need to be changed elsewhere, this universal tapered adapter can be used for different types of tower cranes with similar other parameter requirements without the need to make new tower crane foundations. If the installation direction of another tower crane is the same as the original, the original universal tapered adapter structure can be used directly. If the installation direction of another tower crane is different from the original tower crane installation direction, it is only necessary to remove the steel plate connecting bolts, weld and cut the tapered adapter, remove the adapter, rotate the adapter to the appropriate tower crane installation direction, re-match the second connection end with the tower crane's connecting base 41, and weld the first connection end. The adapter can then be reused for the new tower crane installation. The installation is simple and reduces the time spent on calculating various parameters of the adapter and the cost of manufacturing the adapter.

[0163] The above description is merely a preferred embodiment of the present invention and is not intended to limit the invention. For those skilled in the art, the present invention can have various modifications, variations, and alterations. Any modifications, substitutions, or improvements made within the spirit and principles of the present invention should be included within the scope of protection of the present invention.

Claims

1. A universal tapered transition joint structure, comprising a steel box girder foundation and a tower crane (4), wherein a connection mounting position for the tower crane is provided on the steel box girder foundation, and a connecting base (41) is provided at the bottom end of the tower crane, wherein there is a misalignment angle between the connection mounting position and the connecting base (41), characterized in that, It also includes a conversion connector (5), which includes a connector body (501). The connector body (501) includes a first connecting end (502) corresponding to the steel box girder foundation and a second connecting end (505) corresponding to the connecting base (41). The cross-sectional area of ​​the first connecting end (502) is smaller than the cross-sectional area of ​​the connecting installation position. The adapter (5) is welded to the connection mounting position via the first connection end (502), and the second connection end (505) of the adapter (5) after welding is matched and connected to the connection base (41). The second connecting end (505) includes a connecting panel (506), and the connecting panel (506) and the connecting base are provided with corresponding mounting holes, and fasteners are detachably installed on the mounting holes; The diameter B2 of the connecting panel is greater than the diameter B1 of the connector body, and the connecting panel (506) and the connector body (501) are arranged with their centers overlapping. It also includes several reinforcing ribs (504), which are arranged in right-angled triangles or right-angled trapezoids. One right-angled side of the reinforcing rib is welded to the outer side of the connector body, and the other right-angled side of the reinforcing rib is welded to the bottom side of the connecting panel. A plurality of the reinforcing ribs (504) are evenly arranged around the centerline of the connector body (501), and a connector mounting hole (507) is provided between two adjacent reinforcing ribs (504). The main body of the joint is formed by welding several vertical steel plates end to end to form a hollow structural component. The steel box girder foundation includes a first steel box girder (1) and a second steel box girder (2) that intersects with the first steel box girder. The sides of the first steel box girder and / or the second steel box girder are also provided with reinforcing steel plates (6) corresponding to the reinforcing ribs. One side of the reinforcing steel plate is welded and fixed to the foundation of the steel box girder, and the top end face of the reinforcing steel plate is welded and connected to the bottom end of the reinforcing rib.

2. A calculation method for a universal tapered transition joint structure, applicable to the universal tapered transition joint structure described in claim 1, characterized in that, Includes the following steps: Step 1) Based on the tower crane model, consult the tower crane instruction manual to determine the following values ​​for the standard section width B, the standard bending moment MK, the standard torque MZ, the standard vertical load FK, the standard horizontal shear force VK, and the width B2 of the connecting base steel plate of the standard section of the tower crane under working and non-working conditions. Step 2) Lay out the foundation for the tower crane steel box girder. The specific layout needs to be determined according to the construction requirements. Step 3) Arrange the location of the tower crane universal conversion tapered joint according to the actual conditions of the construction site; Step 4) Assuming the dimensions of the steel plate for the universal conversion tapered joint structure, perform verification calculations. The verification steps are shown in the following formula. If the verification is successful, assume the dimensions are acceptable; otherwise, thicken the steel plate. Where: 1) Based on the combination formula of basic load effects in the "Code for Design of Building Structures" GB50009, convert the standard values ​​into design values: Where FK is the standard value of vertical load in the tower crane's instruction manual, which is a permanent load, and the partial factor for permanent loads is taken as 1.3; MK is the standard value of bending moment of the tower crane, MZ is the standard value of torque of the tower crane, and VK is the standard value of horizontal shear force of the tower crane. MK, MZ, and VK are variable loads, and the combination factor for variable loads is taken as 1.

5. 2) Using the calculation formula for the eccentric vertical force of a single pile in a pile group foundation as specified in the "Code for Design of Building Foundations" GB50007, the design values ​​of the universal conversion tapered joint structure under both working and non-working conditions were calculated, totaling eight values. The largest value was taken as Fmax. The calculation formula is as follows: —Equation 1 in, —Equation 2, The height of the tower crane steel box girder is the same as the height of the first and second steel box girder cross-sections. 3) Calculate the force V along the X-axis respectively. 1max Force V along the Y-axis 2max The calculation formula is as follows: —Equation 3 —Equation 4 in, Force is transmitted along axes X1 and Y1. V1max is the maximum design value converted from the standard value in the tower crane instruction manual, and V2max is the horizontal shear force converted from the tower crane torque, with V1max being horizontally perpendicular to V2max. 4) Calculate the bending strength of the vertical steel plate; According to mechanics of materials, the moment of inertia I of the planar portion enclosed by the vertical steel plate is calculated using the following formula: —Equation 5 Wherein, t1: thickness of the vertical steel plate; t2: thickness of the reinforcing rib; B1: width of the joint body; B2: width of the connecting panel 506; Based on Equation 5 and mechanics of materials, calculate the section modulus: —Equation 6; Where B: the width of a standard section of the tower crane. Calculate the cross-sectional area: —Equation 7 The strength of the weld and steel plate is calculated based on the calculated cross-sectional area and section modulus W obtained above. —Equation 8 in, h1: Steel plate thickness of the connecting base of the tower crane standard section; h2: Steel plate thickness of the 506 connecting panel of the universal tapered adapter; h3: Overall height of the universal tapered adapter; By consulting the steel structure handbook, we obtained the steel plate strength grade and the corresponding design strength 1 for the steel plate thickness, as well as the design value 2 for the bending strength of equal-strength welded steel plates, and the design value 3 for the shear strength of equal-strength welded steel plates. When the bending strength calculated by formula 8 is less than the design strength 1 of the steel plate and the design bending strength 2 of the weld of equal strength, then the above dimensions are valid. When the bending strength calculated by formula 8 is greater than the design strength 1 of the steel plate and the design bending strength 2 of the equal strength weld, it is necessary to increase the width B1 of the first connection end, or increase the thickness t1 of the vertical steel plate (503), or reduce the overall height h3 of the universal tapered conversion joint body; then repeat the above calculation until the bending strength calculated by formula 8 is less than the design strength 1 of the steel plate and the design bending strength 2 of the equal strength weld. 5) Calculate the shear strength of the vertical steel plate. According to the theory of material strength: —Equation 9 If the shear strength calculated by formula 9 is less than the design strength of the equal-strength shear strength 3, then the above calculation meets the requirements; If the shear strength calculated by formula 9 is greater than the shear strength design value of 3, then the width B1 of the joint body needs to be increased, or the thickness t1 of the vertical steel plate needs to be increased; then repeat the above calculation steps 2)-5) until the shear strength calculated by formula 9 is less than the shear strength design value of 3. 6) Calculation of steel plate connecting bolts (508) (i) Assuming the opening area of ​​the joint mounting hole (507) is A1, if the size of the connecting bolt is the same as that of the connecting base of the tower crane standard section, and the thickness of the connecting panel h2 is greater than the thickness of the connecting base of the tower crane standard section h1, then the shear strength of the mounting hole of the connecting base of the tower crane standard section does not need to be calculated. (ii) Let the opening area of ​​the connecting bolt (508) be A2, the shear design strength of the connecting bolt be V1, and the compressive design strength be V2; Based on the minimum values ​​of the compressive strength and shear strength of the high-strength bolts, the smaller value is taken as FF1; The bending moment MF1 is calculated using the following formula: —Equation 10; —Equation 11; The flexural strengths F1 and F2 are calculated using the following formulas: —Equation 12; —Equation 13 Wherein, W1 and W2 are the section modulus of the connecting panel (506) enclosed by two adjacent second welds (511); The calculation method for the section modulus (W1, W2) of the connecting panel (506) enclosed by two adjacent second welds (511) shall be implemented with reference to formulas 5 and 6; If the results of formulas 12 and 13 are less than or equal to the design strength of the steel plate 1, then the above calculation meets the requirements; otherwise, the thickness h1 of the connecting base of the tower crane standard section should be increased. 7) The steel selection and welding method for the second weld (511) and the third weld (512) are the same as those for the first weld (510) mentioned above. 8) If all the above calculations are completed, the modeling is valid.

3. A method for fabricating a universal tapered transition joint structure, based on the calculation method for a universal tapered transition joint structure described in claim 2, characterized in that, Includes the following steps: 1) Select a suitable steel plate based on the calculated parameters; 2) Based on the calculated parameters, the steel plate is cut using the acetylene-oxygen cutting method to cut out the universal tapered adapter body, the connecting panel (506) and the reinforcing rib. Then, a steel plate drilling machine is used to drill holes in the connecting panel (506) to form the adapter mounting holes (507). The cut universal tapered adapter body (501), the connecting panel (506) and the reinforcing rib (504) are then ground using a steel plate grinding machine. After the processing of each universal tapered adapter body, connecting panel and reinforcing rib is completed, the universal tapered adapter body, connecting panel and reinforcing rib are assembled together using welding rods and welding machine and then welded using a welding machine.

4. An installation method for a universal tapered adapter structure, based on the universal tapered adapter structure described in claim 1, characterized in that, Includes the following steps: 1) Rotate the adapter to match the required installation angle between the universal tapered adapter and the connection base of the tower crane foundation; 2) After rotation, if the reinforcing rib does not extend beyond the connection and installation position of the steel box girder, the first connection end of the universal tapered conversion joint body is welded to the connection and installation position, and the weld must meet the strength requirements; if the reinforcing rib extends beyond the connection and installation position after rotation, a reinforcing steel plate is welded to the side of the first steel box girder and / or the second steel box girder corresponding to the reinforcing rib. 3) Insert the vertical support rod of the tower crane standard section into the connecting panel, and use fasteners to connect and secure the connecting base of the tower crane to the connecting panel (506). Tighten the fasteners with a torque wrench according to the torque requirements.

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