A construction method suitable for a double-layer composite structure of a cable-net shell with elastic hanging

Abstract

The application discloses a construction method suitable for a double-layer composite structure of a tensile string net shell with elastic hanging, and is characterized by layer-by-layer construction from bottom to top, which solves the precision and quality problems commonly existing in the construction process of the double-layer composite structure of the tensile string net shell with elastic hanging. The construction method of the application reduces the absolute value of installation error through pre-bias, offsets the influence of construction deformation, realizes fine control of error and deformation in the construction process, and significantly improves the precision of structure construction forming. The structure tensioning process control is adopted, the strut does not need to be pre-biased in the strut tensioning process, the construction is convenient, the deflection of the strut can be avoided, the tensioning forming effect is good, the spring system is installed together with the strut but is connected in lag, secondary hoisting is avoided, the amount of high-altitude operation is reduced, the operation difficulty is lowered, and the construction is convenient. The construction sequence is reasonable, the stress state of the structure after forming is consistent with the design state, additional internal force is avoided, and the construction quality is easy to guarantee.

Description

TECHNICAL FIELD

[0001] The present application relates to the field of building steel structure construction, in particular to a construction method of a double-layer composite structure with elastic hanging of a string-net shell. BACKGROUND

[0002] The string-net shell structure has a self-balancing stress mechanism and excellent spanning performance, and has been widely used in the field of large-span space structures in recent years. With the further increase of the demand for architectural functions and aesthetic effects, a system of hanging a large-span sandwich structure by using a spring system under the string-net shell structure has appeared. The lower structure can avoid setting a support system by using the suspension effect of the upper string-net shell structure, thereby providing a large space for the building while achieving a substantial reduction in the amount of steel used.

[0003] The upper and lower double-layer structures of such a system are cooperatively stressed and mutually influenced, but the string-net shell, the spring system and the lower hanging structure are all sensitive to deformation and stress. The projections of the string-net shell joints, the bracing bars, the spring system and the lower structure joints in the design state should be coincident, and the bracing bars and the spring system should only bear axial force. However, during the construction process, the relative errors may be caused by the relatively independent installation of the double-layer structure before the spring system is connected, and the large change in the shape during the tensioning and forming process of the string-net shell may cause problems such as deviation of the bracing bar shape, which seriously affects the installation accuracy and further causes the bracing bars and the spring system to be installed non-perpendicularly. This situation not only affects the visual effect of the building, but also changes the stress state of the structure, which may cause construction defects of the structure and pose a safety risk. Therefore, for such a structure system, it is of great engineering significance to design a construction method that can effectively reduce construction errors, improve the installation accuracy of the bracing bars and the spring system, and conveniently construct the structure to reduce construction defects and make the formed state of the structure meet the design concept. It is a problem to be solved by the skilled in the art. SUMMARY

[0004] The purpose of the present application is to provide a construction method suitable for such a structure system to solve the precision and quality problems commonly existing in the construction process of the double-layer composite structure with elastic hanging of a string-net shell. The method can realize fine control of errors during the construction process, effectively improve the installation accuracy of the structure, has strong feasibility, does not change the design stress state of the structure during the construction process, reduces construction defects, and ensures the forming effect of the structure.

[0005] The above technical purpose of the present application is achieved by the following technical solution: a construction method suitable for a double-layer composite structure with elastic hanging of a string-net shell, which is constructed layer by layer from bottom to top, and the specific steps are as follows:

[0006] (1) Set up the temporary support system required for the installation of the lower structure;

[0007] (2) Through the simulation analysis and calculation of the construction deformation of the lower structure throughout the construction process, the pre-offset values ΔX 下 , ΔY 下 , ΔZ 下 are determined, the assembly coordinates (X+ΔX 下 , Y+ΔY 下 , Z 下 +ΔZ 下 ) are calculated according to the pre-offset values and the design coordinates (X, Y, Z 下 ) of the lower structure, and then the assembly of the lower structure is completed through the construction process such as hoisting, and the assembly error of the lower structure is measured as ΔX' 下 , ΔY' 下 , ΔZ' 下 ;

[0008] (3) The temporary support system required for the erection of the upper tense chain net shell structure is set up;

[0009] (4) Through the simulation analysis and calculation of the construction deformation of the upper tense chain net shell throughout the construction process, the pre-offset values ΔX 上 , ΔY 上 , ΔZ 上 are determined, the assembly coordinates (X+ΔX 上 , Y+ΔY 上 , Z 上 +ΔZ 上 ) are calculated according to the pre-offset values and the design coordinates (X, Y, Z 上 ) of the tense chain net shell, and then the assembly of the tense chain net shell (excluding the cable system and the strut) is completed through the construction process such as hoisting, and the assembly error of the tense chain net shell is measured as ΔX' 上 , ΔY' 上 , ΔZ' 上 ;

[0010] (5) The center point A of the lower structure hanging joint is taken as the reference point, the projection point B falling within the range of the upper tense chain net shell joint is obtained by vertical projection, the theoretical pre-offset values of the point B in the horizontal direction are calculated as , and the point C is obtained after the pre-offset according to the value, the strut is installed taking the point C as the control point, and then the cable system is installed;

[0011] (6) The tense chain net shell is constructed by adopting the symmetric step-by-step tensioning process of the two ends of the cable, and the shape changes ΔX 上1 , ΔY 上1 , ΔZ 上1 of the tense chain net shell are monitored and recorded in the process;

[0012] (7) The temporary support system of the upper tense chain net shell structure is unloaded, and the shape changes ΔX 上2 , ΔY 上2 , ΔZ上2 ;

[0013] (8) Install the spring system, the double-layer structure is connected by the spring system, and no obvious shape change occurs in the structure during the process;

[0014] (9) Uninstall the temporary support system of the lower-layer structure, and monitor and record the shape changes of the double-layer structure, respectively, ΔX 上3 , ΔY 上3 , ΔZ 上3 and ΔX 下1 , ΔY 下1 , ΔZ 下1 during the process;

[0015] (10) Install the auxiliary structure and apply the use load, etc., and the construction is completed. Monitor and record the shape changes of the double-layer structure, respectively, ΔX 上4 , ΔY 上4 , ΔZ 上4 and ΔX 下2 , ΔY 下2 , ΔZ 下2 during the process.

[0016] Further, the relationship between the pre-offset value of the lower-layer structure in the above construction method and the deformation during the construction process is Without considering the assembly error, the formed coordinate value of the lower-layer structure when the construction is completed is consistent with the design coordinate.

[0017] Further, the relationship between the pre-offset value of the tensile chain net shell structure in the above construction method and the deformation during the construction process is Without considering the assembly error, the formed coordinate value of the tensile chain net shell structure when the construction is completed is consistent with the design coordinate.

[0018] Further, in the above construction method, the upper tensile chain net shell and the lower-layer structure are not limited to be assembled by hoisting technology, and different technologies such as lifting can also be used according to the construction conditions.

[0019] Further, in the above construction method, the pin shaft is connected between the strut and the tensile chain net shell, the pin shaft ear plate is not assembled with the tensile chain net shell at the same time, but is installed together with the strut, and the ear plate is installed at the installation position determined by the control point C. When the construction is completed, the horizontal installation error between the strut and the tensile chain net shell and the relative error between the strut and the hanging node of the lower-layer structure are The relative error between the assembly of the double-layer structure is neutralized by adjusting the installation position of the strut, and the absolute value of the error is reduced.

[0020] Further, in the above construction method, the spring system is installed on the ground together with the strut, is in place in the air together with the strut, but is not connected with the hanging node of the lower-layer structure, which can avoid the secondary hoisting of the spring system and reduce the amount of high-altitude operation.

[0021] Further, in the construction method, the two ends of the cable are symmetrically and stepwise tensioned, the strut does not need to be pre-biased during tensioning, the tensioning stroke of the two ends of the cable is adjusted in real time according to the verticality observation result of the strut during stepwise tensioning, if the strut deviates to one side, it indicates that the tensioning stroke on the deviating side is too large, the tensioning should be temporarily suspended, and the tensioning stroke on the other side is too small, the tensioning should be continued, until the strut deviation is restored, and the two sides continue to be tensioned at the same time.

[0022] Further, in the construction method, the upper string-net shell structure should be unloaded after tensioning, then the spring system is connected, and finally the temporary support system of the lower structure is unloaded. Under this construction sequence, the spring system is avoided from being stressed in advance, the spring only bears the vertical load transmitted by the lower structure after being connected, which is more consistent with the design stress state. The spring is also avoided from being connected in advance, which causes the tensioning construction deformation of the string-net shell to generate construction additional internal force of the lower structure, and affects the safety of the structure.

[0023] In summary, the present application has the following advantages:

[0024] (1) The construction method reduces the absolute value of the installation error by pre-biasing, offsets the influence of construction deformation, realizes fine control of error and deformation during construction, and significantly improves the precision of structure construction forming;

[0025] (2) The construction method uses structure tensioning process control, the strut does not need to be pre-biased during tensioning, the construction is convenient, and the strut deviation phenomenon is avoided, the tensioning forming effect is good;

[0026] (3) The spring system is installed with the strut but connected later, avoiding secondary lifting, reducing the amount of high-altitude work and the difficulty of work, and facilitating construction;

[0027] (4) The construction sequence is reasonable, the stress state of the structure after forming is consistent with the design state, additional internal force is avoided, and the construction quality is easy to guarantee. BRIEF DESCRIPTION OF DRAWINGS

[0028] Figure 1 is a three-dimensional schematic view of the structure of the embodiment of the present application;

[0029] Figure 2 is a cross-sectional schematic view of the structure of the embodiment of the present application;

[0030] Figure 3 is a schematic view of the construction process of the structure of the embodiment of the present application;

[0031] Figure 4 is a three-dimensional schematic view of the connection node of the lower net shell and the spring system in the embodiment of the present application;

[0032] Figure 5 This is a three-dimensional schematic diagram of the upper tensioned wire mesh shell node in an embodiment of the present invention;

[0033] Figure 6 This is a top view of the upper tensioned wire mesh shell node in an embodiment of the present invention;

[0034] Figure 7 This is a three-dimensional schematic diagram of the connection between the bottom node of the strut and the spring system in an embodiment of the present invention.

[0035] In the diagram: 1. Tensed wire mesh shell; 2. Structural column; 3. Stud; 4. Cable system; 5. Spring system; 6. Lower mesh shell; 7. Concrete beam; 8. Temporary support system for the lower mesh shell; 9. Temporary support system for the tensioned wire mesh shell; 10. Lower mesh shell hanging node; 11. Tensed wire mesh shell node; 12. Bottom node of the strut. Detailed Implementation

[0036] The following is in conjunction with the appendix Figures 1-7 The present invention provides a more detailed description of the construction method applicable to a double-layer composite structure of tensioned wire mesh shell with elastic suspension.

[0037] like Figure 1 and Figure 2 As shown, the present invention relates to a double-layer composite structure system of tensioned wire mesh shell with elastic suspension, mainly including tensioned wire mesh shell 1, structural columns 2, struts 3, cable system 4, spring system 5, and lower wire mesh shell 6; the tensioned wire mesh shell 1 forms a self-balancing force system through struts 3 and cable system 4 and is supported by structural columns 2 to form a stable structure; the lower wire mesh shell 6 is supported on concrete beams 7 around its perimeter and is suspended from the strut nodes of tensioned wire mesh shell 1 by spring system 5, and works together with the upper tensioned wire mesh shell 1 to form a double-layer composite structure;

[0038] A construction method for a double-layer composite structure with elastic suspension and tensioned wire mesh shell includes the following steps:

[0039] 1. For example Figure 3 As shown, first, a temporary support system 8 is erected for the installation of the lower mesh shell 6;

[0040] 2. The total deformation of the lower reticulated shell 6 is calculated through simulation analysis of the entire construction process. The absolute value of the total deformation in each direction is the pre-deflection value ΔX. 下 ΔY 下 ΔZ 下 The pre-deflection direction is opposite to the direction of the total deformation during construction. This is based on the pre-deflection value and the design coordinates (X, Y, Z) of the lower reticulated shell 6. 下 The assembly coordinates (X+ΔX) were calculated. 下 ,Y+ΔY 下 Z 下 +ΔZ 下, the assembling error of the lower-layer net shell 6 is ΔX' 下 , ΔY' 下 , and ΔZ' 下 .

[0041] 3. Setting up the temporary support system 9 required for installing the upper-layer tensile chain net shell 1;

[0042] 4. Calculating the total deformation of the upper-layer tensile chain net shell 1 during the whole construction process through simulation analysis, and the absolute value of the total deformation in each direction is the pre-offset value ΔX 上 , ΔY 上 , and ΔZ 上 . The pre-offset direction is opposite to the direction of the total deformation. The assembling coordinates (X+ΔX 上 , Y+ΔY 上 , and Z 上 +ΔZ 上 ) are calculated according to the pre-offset value and the design coordinates (X, Y, Z 上 ) of the tensile chain net shell 1. The assembling of the tensile chain net shell 1 (excluding the cable system 4 and the strut 3) is completed through the sectional hoisting process according to the assembling coordinates, and the assembling error of the tensile chain net shell 1 is ΔX' 上 , ΔY' 上 , and ΔZ' 上 .

[0043] 5. As shown in Figures 4 to 6 , the center point A of the lower-layer net shell hanging node 10 is taken as the reference point to vertically project upward to obtain the projection point B, which falls within the range of the upper-layer tensile chain net shell node 11 (when there is an assembling error and installation pre-offset, the point B does not coincide with the center point O of the tensile chain net shell grounding node 11). According to the difference between the relative error of the assembling of the tensile chain net shell 1 and the lower-layer net shell 6 and the installation pre-offset value, the installation control point of the strut 3 is also pre-offset in the horizontal direction. Taking the point B as the reference, the horizontal pre-offset values are The pre-offset direction is the direction of the point B pointing to the center point O of the tensile chain net shell node 11. After pre-offset according to the values, the point C is obtained. The strut 3 is installed by taking the point C as the control point.

[0044] As shown in Figure 7 , the bottom end node 12 of the strut 3 and the spring system 5 are pre-connected on the ground, so that the spring system 5 can be positioned together when the strut 3 is installed, but the spring system 5 cannot be connected with the lower-layer net shell hanging node 10 at this time. Then, the cable system 4 is installed and pre-tightened.

[0045] 6. The upper layer of the tensile string structure 1 is tensioned by the symmetrical and hierarchical tensioning process of the two ends of the cable. During the hierarchical tensioning process, the tensioning stroke of the two ends of the cable is adjusted in real time according to the verticality observation results of the strut. If the strut deflects to one side, the tensioning stroke of the deflection direction is too large, and the tensioning should be temporarily suspended. The tensioning stroke of the other side is too small, and the tensioning should be continued. When the deflection of the strut is restored, the two sides continue to be tensioned simultaneously. The shape changes ΔX 上1 , ΔY 上1 , and ΔZ 上1 of the tensile string structure 1 are monitored and recorded during the process.

[0046] 7. The temporary support system 9 of the upper layer of the tensile string structure 1 is unloaded. The shape changes ΔX 上2 , ΔY 上2 , and ΔZ 上2 of the tensile string structure 1 are monitored and recorded during the process.

[0047] 8. The spring system 5 is connected to the hanging node 10 of the lower layer of the tensile string structure 6. During this process, the structure does not have obvious shape changes.

[0048] 9. The temporary support system 8 of the lower layer of the tensile string structure is unloaded. At this time, the spring system 5 starts to bear force. The shape changes ΔX 上3 , ΔY 上3 , and ΔZ 上3 of the tensile string structure 1 and ΔX 下1 , ΔY 下1 , and ΔZ 下1 of the lower layer of the tensile string structure 6 are monitored and recorded during the process.

[0049] 10. The auxiliary structure such as the roof panel is installed, and the construction is completed. The shape changes ΔX 上4 , ΔY 上4 , and ΔZ 上4 of the tensile string structure 1 and ΔX 下2 , ΔY 下2 , and ΔZ 下2 of the lower layer of the tensile string structure 6 are monitored and recorded during the process.

[0050] When the construction is completed, the total deformation of the tensile string structure 1 and the lower layer of the tensile string structure 6 caused by the construction is offset by the corresponding pre-offset values. Without considering the assembly error, the tensile string structure 1 and the lower layer of the tensile string structure 6 reach the design coordinate position. At this time, the projection positions of the connection nodes of the tensile string structure 1, the strut 3, the spring system 5, and the lower layer of the tensile string structure 6 coincide, which meets the design shape and force requirements. If the assembly error is considered, the deviation between the tensile string structure 1 and the lower layer of the tensile string structure 6 and the design position is the assembly error. Without the influence of the construction deformation, the horizontal installation error between the strut 3 and the tensile string structure 1 and the horizontal installation error between the strut 3 and the lower layer of the tensile string structure 6 are is the average value of the relative assembly error of the cable-net shell 1 and the lower-layer net shell 6, further reduces the error extreme value, improves the installation precision, and can also preferably ensure the structure forming effect and stress state.

[0051] The above only describes the preferred embodiments of the present application, and the protection scope of the present application is not limited to the above-described embodiments only, and any technical solution falling within the concept of the present application belongs to the protection scope of the present application.

[0052] It should be noted that, for those skilled in the art, some improvements and refinements without departing from the principles of the present application should also be considered as the protection scope of the present application.

Claims

1. A construction method suitable for a double-layer composite structure of a cable-net dome with elastic hanging, which is constructed layer by layer from bottom to top, characterized in that The specific steps are as follows: (1) erecting a temporary support system required for installing the lower structure; (2) Through the whole construction process simulation analysis and calculation of the construction deformation of the lower structure and determine the pre-offset value ΔX 下 , ΔY 下 , ΔZ 下 , according to the pre-offset value and the design coordinates (X, Y, Z 下 ) of the lower structure, the assembly coordinates (X+ΔX 下 , Y+ΔY 下 , Z 下 +ΔZ 下 ) are calculated, and then the lower structure is assembled through hoisting and other construction processes. The assembly error of the lower structure is measured as ΔX ' 下 , ΔY ' 下 , ΔZ ' 下 ; (3) erecting a temporary support system required for installing the upper tense chain net shell structure; (4) Through the whole construction process simulation analysis and calculation of the construction deformation of the upper string net shell and determine the pre-offset value ΔX 上 , ΔY 上 , ΔZ 上 , according to the pre-offset value and the design coordinates (X, Y, Z 上 ) of the string net shell, the assembly coordinates (X+ΔX 上 , Y+ΔY 上 , Z 上 +ΔZ 上 ) are calculated, and then the string net shell is assembled through hoisting and other construction processes. The string net shell does not include the cable system and the strut, and the assembly error of the string net shell is measured as ΔX ' 上 , ΔY ' 上 , ΔZ ' 上 ; (5) The center point A of the following layer structure hanging joint is taken as the reference point to project vertically upward to obtain the projection point B, which falls within the range of the upper layer tensile chain net shell joint. The theoretical pre-offset value of point B in the horizontal direction is calculated as Point C is obtained after pre-offsetting by this value, and a support rod is installed with C as the control point, followed by installation of the cable system; (6) The upper layer of the catenary net shell is tensioned by adopting the symmetric grading tensioning process at both ends of the cable, and the changes ΔX 上1 , ΔY 上1 , and ΔZ 上1 of the catenary net shell are monitored and recorded during the process. (7) Unloading the temporary support system of the upper-layer tensegrity shell structure, monitoring and recording the shape change ΔX 上2 , ΔY 上2 , ΔZ 上2 of the tensegrity shell during the process; (8) installing the spring system, and the double-layer structure is connected through the spring system, and no obvious shape change of the structure occurs in this process; (9) Unload the temporary bracing system of the lower structure, monitor and record the changes in the configuration of the double-deck structure as ΔX 上3 , ΔY 上3 , ΔZ 上3 and ΔX 下1 , ΔY 下1 , ΔZ 下1 respectively during the process; (10) Installation of auxiliary structures and application of service loads, etc., construction completed, during which the configuration changes of the double-layer structure were monitored and recorded as ΔX. 上4 ΔY 上4 ΔZ 上4 and ΔX 下2 ΔY 下2 ΔZ 下2 .

2. The construction method for the double-layer composite structure with the tensile-arched-mesh suspended ceiling according to claim 1, characterized in that: The relationship between the pre-offset value of the lower structure and the deformation during construction in the above construction method is The formed coordinate value of the lower structure at the time of completion of construction is consistent with the design coordinate value without considering the assembly error.

3. The construction method for the double-layer composite structure with the tensile-arched-mesh suspended ceiling according to claim 1, characterized in that: The relationship between the pre-offset value of the cable-net shell structure in the construction method and the deformation in the construction process is Without considering the assembling error, the forming coordinate value of the cable-net shell structure at the completion of the construction is consistent with the design coordinate.

4. The construction method for the double-layer composite structure with the tensile-arched-mesh suspended ceiling according to claim 1, characterized in that: In the above construction method, the upper tense chain net shell and the lower structure are not limited to being assembled by hoisting process, and different processes such as lifting can also be used according to the construction conditions.

5. The construction method suitable for the double-layer composite structure of the tensile-arched-mesh shell with elastic hanging according to claim 1, characterized in that: In the construction method, the pin shafts are connected between the struts and the tensegrity shell, the pin shaft ear plates are not assembled simultaneously with the tensegrity shell, but are installed together with the struts, the ear plates are determined to be installed at the control point C, and when the construction is completed, the horizontal installation error between the struts and the tensegrity shell and the relative error between the struts and the lower layer structure hanging nodes are The relative error between the double-layer structures is neutralized by adjusting the installation position of the struts, so that the absolute value of the error is reduced.

6. The construction method for the double-layer composite structure with the tensile-arched-mesh suspended ceiling according to claim 1, characterized in that: In the above construction method, the spring system and the strut are installed on the ground together, and are in place in the air with the strut but are not connected with the hanging nodes of the lower structure, which can avoid the secondary hoisting of the spring system and reduce the amount of high-altitude operation.

7. The construction method for the double-layer composite structure with the tensile-arched-mesh suspended ceiling according to claim 1, characterized in that: In the above construction method, the symmetric and staged tensioning method is used for the two ends of the cable when the tense chain net shell structure is tensioned, and the strut does not need to be pre-biased during tensioning. During the staged tensioning process, the tensioning stroke of the two ends of the cable is adjusted in real time according to the verticality observation results of the strut. If the strut deviates to one side, it means that the tensioning stroke in the direction of the strut deviation is too large, and the tensioning should be temporarily suspended, and the tensioning stroke on the other side is too small and should be continuously tensioned, until the strut deviation condition is restored, and then the two sides are continuously tensioned at the same time.

8. The construction method for the double-layer composite structure with the tensile-arched-mesh suspended ceiling according to claim 1, characterized in that: In the above construction method, the upper tense chain net shell structure should be unloaded after tensioning, and then the temporary support system of the lower structure is connected, and finally the temporary support system of the lower structure is unloaded. In this construction sequence, the spring system is not subjected to stress in advance, and only bears the vertical load transmitted by the lower structure after the spring is connected, which is more in line with the design stress state, and also avoids the additional internal force of the lower structure caused by the deformation of the tense chain net shell during tensioning construction when the spring is connected in advance, which affects the safety of the structure.

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