Installation method of annular crossed cable system supporting dome structure
The technical field is as follows:
the invention relates to an installation method of an annular crossed cable system supporting dome structure, and belongs to the field of space cable truss structures.
Background art:
with the continuous development of society, the demand of people for public activity spaces such as large exhibition halls, sports stadiums and the like is increasing day by day. This phenomenon has also prompted constant innovation in the form of large-span spatial structures. Not only is the innovation in the aspects of safety and economy, but also the innovation in the aspects of modeling and construction, thereby meeting the continuously updated aesthetic requirements of people and facilitating the construction operation of constructors. In recent years, large-span suspended dome structures, cable dome structures and cable truss structures are widely applied to the construction of stadiums at home and abroad.
The suspended dome structure is reasonable in stress, high in structural efficiency and clear in force transmission path, the stress performance of the high-strength stay cable is fully utilized, the steel consumption is reduced while the structural rigidity is guaranteed, and the structure becomes light and rich in expressive force. Cable dome and cable truss structures are typical cable structures, and are widely applied to public buildings such as stadiums due to the factors of strong space spanning capacity, low steel consumption and the like.
However, there are significant disadvantages to either a suspended dome structure or a cable dome or cable truss structure:
1. the suspended dome structure has obvious key components, namely annular cables, and once the annular cables fail, the annular cables can cause the failure of the inclined stay cables and the vertical stay bars, and even directly cause the continuous collapse of the structure.
2. The cable truss structure cannot ensure out-of-plane stability due to the structure, and stabilizing cables need to be arranged along the circumferential direction to ensure out-of-plane stability of each cable truss. The collapse resistance of the structure is weak, the spoke type cable truss structure connects cable trusses together by means of central ring cables, and the structure obtains enough rigidity and bearing capacity by tensioning the central ring cables. Once the central ring cable is broken, the structural rigidity is obviously reduced, and even the whole structure collapses; meanwhile, the upper layer rod piece and the lower layer rod piece are both flexible inhaul cables, the space node coordinate positioning is complex, and the construction difficulty is high.
3. The cable dome structure also has obvious key components, namely annular cables, and once the annular cables fail, the failure of the inclined stay cables and the vertical stay bars can be caused, and even the continuous collapse of the structure can be directly caused; meanwhile, the upper layer rod piece and the lower layer rod piece are both flexible inhaul cables, the space node coordinate positioning is complex, and the construction difficulty is high.
For such structures, the mounting method is relatively mature.
For example, the method for installing the string-supported dome cable rod system by lifting ring by ring comprises the following steps: firstly, installing an upper latticed shell, secondly assembling the cable rod lifting unit, and then lifting the cable rod lifting unit ring by taking the upper latticed shell as a platform.
The installation method can achieve a good effect when used for installing structures such as a suspended dome and the like, but for the annular cross cable system supporting dome structure, the node structure is complex, the rigidity of the lower cable system is low before prestress is applied, and the installation method adopting integral lifting cannot be achieved, so that the construction method suitable for the annular cross cable system supporting dome structure is provided.
The invention content is as follows:
the invention aims to provide a novel installation method of a large-span annular cross cable system supporting dome structure, which is suitable for buildings such as stadiums and the like, aiming at the particularity of the annular cross cable system supporting dome structure. The novel annular crossed cable system supporting dome structure consists of an upper latticed shell (1), a lower annular crossed cable system (2) and vertical supporting rods (3). Each cable in the annular crossed cable system is kept relatively independent and can bear load independently, even if one cable fails due to an accident, the structure can immediately redistribute internal force, the rest intact cable systems can provide bearing force, and the bearing force and the upper latticed shell bear force together, so that the structure cannot collapse integrally, and the redundancy of the structure is improved.
The purpose of the invention is realized by the following technical scheme:
the method for installing the annular crossed cable system supported dome structure is characterized in that the annular crossed cable system supported dome structure mainly comprises an upper latticed shell (1), a lower annular crossed cable system (2) and a plurality of vertical support rods (3); the lower annular crossed cable system (2) is an annular structure formed by encircling a plurality of cable crossed dispersed points; the vertical upper ends of the vertical support rods (3) are connected with the upper latticed shell (1), the lower ends of the vertical support rods are connected with the lower annular crossed cable system (2), the upper end of each vertical support rod (3) is connected with a grid cross point in the upper latticed shell (1), and the lower ends of the vertical support rods are connected with cable crossed positions of the lower annular crossed cable system (2). The upper latticed shell can be a Schwedler type, a cross square type, a three-way type, a Kaiwaite type, a rib ring type, a short-distance linear type or other forms of grids according to different grid division forms; according to different shapes of the reticulated shell, the reticulated shell can be a spherical reticulated shell or a cylindrical reticulated shell, etc.; according to the difference of the number of layers of the reticulated shell, the reticulated shell can be a single-layer reticulated shell or a double-layer reticulated shell; the lower annular crossed cable system (2) is formed by cable crossed parts formed by mutually crossing a plurality of relatively independent cables. The lower annular crossed cable system can be of a one-layer, two-layer or multi-layer annular structure; the two-layer or multi-layer annular structure is positioned at different heights up and down and is a coaxial two-layer or multi-layer annular structure; the cross part of the inhaul cable adopts a double-layer pressing plate type clamp node, and the double-layer pressing plate type clamp node is connected with the vertical supporting rod in a pin type. Each cable is independent, can bear the load alone, even one because of unexpected the inefficacy, can carry out internal force redistribution immediately, has improved the redundancy of structure.
The method for installing the annular crossed cable system supported dome structure is characterized by comprising the following steps of:
the method comprises the following steps: prefabricating a rod piece for preparing an upper-layer net shell and a corresponding node for assembling an annular crossed cable system supporting dome structure in a factory; after the net cage is transported to an installation site, the upper net cage is firstly assembled in a slicing mode on the ground, after the assembly is completed, each slice area of the upper net cage is lifted to a preset position by a truck crane, then a full scaffold is set up for fixing, and after all slice areas are lifted, the position of each slice area is finely adjusted, so that interfaces at the edges of each slice area are matched; after all the interfaces are matched, all the areas are connected on site to form a complete upper latticed shell; after the upper-layer reticulated shell is spliced, welding the whole upper-layer reticulated shell to the embedded steel plate of the base, and permanently fixing;
step two: prefabricating a guy cable, a vertical stay bar and a double-layer pressing plate type clamp in a factory, and transporting to a site for installation; after prefabrication is finished, marking is carried out on the crossed part of the inhaul cable according to a drawing, and a double-layer pressing plate type clamp is convenient to install;
step three: the lower end of the corresponding node of the upper latticed shell is matched and fixedly connected with the upper end of the vertical stay bar;
step four: matching and fixing the lower end of the vertical stay bar, the double-layer pressing plate type clamp and the stay cable to be crossed;
step five: applying prestress: after all the inhaul cables and the double-layer pressing plate type clamp are installed, prestress is applied to the inhaul cables;
step six: and clamping the double-layer pressing plate type clamp.
The specific steps of the first step are as follows: firstly, the rod pieces of the upper latticed shell are divided into a plurality of types according to the length, the number of the rod pieces with each type of length is determined, and the number of the nodes is determined at the same time. And then, carrying out factory processing strictly according to construction drawings. After the processing is finished, the steel plate is transported to a construction site by a truck for installation.
The third step comprises the following specific steps: and after the upper latticed shell is installed, installing the upper nodes of the vertical supporting rods on the corresponding nodes according to the order of installing the upper latticed shell.
The fourth step comprises the following specific steps: the lower end of the vertical stay bar is provided with two parallel double-lug plates with holes; the double-layer pressing plate type clamp comprises four clamping plates, and a first long clamping plate, a second long clamping plate, a third long clamping plate and a fourth long clamping plate are sequentially arranged from top to bottom; the lower surfaces of the first long clamping plate and the third long clamping plate are respectively provided with a groove, the upper surfaces of the second long clamping plate and the fourth long clamping plate are respectively provided with a groove, the first long clamping plate and the second long clamping plate are overlapped to form a first layer of double-layer plate, a through hole is formed in the middle of the first layer of double-layer plate, and the first long clamping plate and the second long clamping plate are fixed through a bolt; the third long clamping plate and the fourth long clamping plate are overlapped to form a second layer of double-layer plate, a through hole is formed in the middle of the second layer of double-layer plate, and the third long clamping plate and the fourth long clamping plate are fixed through a bolt; the second long splint is connected with the third long splint through a knob, and the distance and the angle between the second long splint and the third long splint are adjustable; the upper surface of the first long splint is provided with a single ear plate with a hole; a single lug plate of the double-layer pressing plate type clamp is inserted between the parallel double lug plates at the lower end of the vertical stay bar, holes are aligned with the holes, and the bolts are fixedly connected;
and respectively fixing two inhaul cables to be crossed in through holes of a first layer of double-layer plate and a second layer of double-layer plate of the double-layer pressing plate type clamp, but allowing the clamped inhaul cables to slide in the through holes.
The concrete steps of the fifth step are as follows: tensioning each cable in a synchronous tensioning mode, wherein a tensioning counterforce device installed at a node is firm, reliable and easy to disassemble; the influence of the guy cable on the external upper latticed shell is considered during tensioning, the deformation of the upper latticed shell is controlled in a symmetrical tensioning mode, the upper latticed shell is tensioned in batches in a fixed direction in three stages, the tensioning process is divided into three stages, the first stage is tensioned to 30% of a target cable force, the second stage is tensioned to 60% of the target cable force, and the third stage is overstretched to 105% of the target cable force to offset the prestress loss.
The sixth step comprises the following specific steps: after all the inhaul cables are tensioned, all the nodes are checked and finely adjusted, the hexagonal bolts are screwed up after the situation that the inhaul cables are correct is confirmed, the first layer of long clamping plates of the double-layer pressing plate type clamp nodes are clamped, the vertical supporting rods and the inhaul cables are fixed at the positions of the double-layer pressing plate type clamp nodes and cannot slide, and therefore installation is finished.
The guy cable consists of a guy cable and an anchorage device, the guy cable adopts a Galfan plating layer guy cable or a stainless steel guy cable, the anchorage devices are arranged at two ends of the guy cable, and the adjustable anchorage devices are fork lug sleeves.
Has the advantages that: the method absorbs the excellent installation method of other large-span cable truss structure installation processes, is combined with the annular cross cable system supporting dome structure form, can give full play to the advantages of the annular cross cable system supporting dome structure, and has high practical value.
Drawings
FIG. 1 is a fragmentary view of an upper portion of a latticework shell of an annular cross-rigging supported dome structure;
FIG. 2 is an isometric view of the upper latticework shell of the annular cross-rigging supported dome structure;
FIG. 3 is a diagram of the upper latticework shell and vertical struts of an annular cross-rigging supported dome structure;
FIG. 4 is an isometric view of an annular cross-rigging support dome structure;
FIG. 5 is a detailed view of a node of the double-layer pressing plate type clamp;
in the figure: A. b, C-Upper reticulated shell segment; 1-upper reticulated shell; 2-lower layer annular cross cable system; 3-vertical brace rod; 4-vertical brace ear plates; 5-clamping plate ear plates; 6. 9, 13 bolts; 7-first long splint; 8-second long splint; 10, a nut; 11-third long splint; 12-fourth long splint; 14-double-layer pressing plate type clamp node.
The specific implementation mode is as follows:
the present invention will be further illustrated with reference to the following examples, but the present invention is not limited to the following examples.
Example 1
The annular cross cable system supporting dome structure mainly comprises an upper latticed shell 1, a lower annular cross cable system 2 and a plurality of vertical supporting rods 3; the lower annular crossed cable system 2 is an annular structure formed by encircling a plurality of cable crossed dispersed points; the vertical upper ends of the vertical support rods 3 are connected with the upper latticed shell 1, the lower ends of the vertical support rods are connected with the lower annular crossed cable system 2, the upper end of each vertical support rod 3 is connected with a grid cross point in the upper latticed shell 1, and the lower ends of the vertical support rods are connected with the cable cross part of the lower annular crossed cable system 2. The upper latticed shell can be a Schwedler type, a cross square type, a three-way type, a Kaiwaite type, a rib ring type, a short-distance linear type or other forms of grids according to different grid division forms; according to different shapes of the reticulated shell, the reticulated shell can be a spherical reticulated shell or a cylindrical reticulated shell, etc.; according to the difference of the number of layers of the reticulated shell, the reticulated shell can be a single-layer reticulated shell or a double-layer reticulated shell, and the embodiment is a single layer; the lower annular cross cable system 2 is composed of cable crossing parts formed by crossing a plurality of independent cables. The lower annular crossed cable system can be of a one-layer, two-layer or multi-layer annular structure; the two-layer or multi-layer annular structure is positioned at different heights up and down, is a coaxial two-layer or multi-layer annular structure, and is a 4-layer structure in the embodiment; the cross part of the inhaul cable adopts a double-layer pressing plate type clamp node, and the double-layer pressing plate type clamp node is connected with the vertical supporting rod in a pin type. Each cable is independent, can bear the load alone, even one because of unexpected the inefficacy, can carry out internal force redistribution immediately, has improved the redundancy of structure. The guy cable consists of a guy cable and an anchorage device, the guy cable adopts a Galfan plating layer guy cable or a stainless steel guy cable, the anchorage devices are arranged at two ends of the guy cable, and the adjustable anchorage devices are fork lug sleeves.
The specific installation method of the annular crossed cable system supporting dome structure comprises the following steps:
the method comprises the following steps: firstly, the rod pieces of the upper latticed shell are divided into a plurality of types according to the length, the number of the rod pieces with each type of length is determined, and the number of the nodes is determined at the same time. And then, carrying out factory processing strictly according to construction drawings. After the processing is finished, the steel plate is transported to a construction site by a truck for installation.
Step two: after the net shell is transported to an installation site, the upper layer net shell 1 is assembled on the ground in a split mode to form A, B, C three or more pieces (see fig. 1), after the assembly is completed, for a large-span structure, three pieces of the upper layer net shell A, B, C are hung to a preset position through a truck crane and then are temporarily fixed through a full scaffold, for a small-span structure, the divided pieces are directly hoisted to the preset position to be initially fixed through a simple device, and the stability of the small-span structure is guaranteed. After all the sections are hoisted, finely adjusting the position of each section to enable the interfaces at the edge of each section to be well matched, and after all the interfaces are matched, carrying out on-site connection of each section on the structure to form a complete upper-layer reticulated shell 1 (see figure 2); after the upper latticed shell 1 is spliced, the upper latticed shell is welded to an embedded steel plate of the base and is permanently fixed;
step three: prefabricating a guy cable, a vertical stay bar 3 and a double-layer pressing plate type clamp 14 in a factory, and transporting to a site for installation; after prefabrication is finished, marking is carried out on the crossed node position of the cable according to a drawing, and the double-layer pressing plate type clamp 14 is convenient to install;
step four: after the upper latticed shell 1 is installed, installing vertical brace upper nodes on corresponding nodes according to the sequence of installing the upper latticed shell 1.
Step five: the double-layer pressing plate type clamp 14 of the stay cable is installed at the lower end of the stay rod, the ear plate 5 is arranged on the upper side of the first layer long clamping plate 7 of the double-layer pressing plate type clamp 14, the ear plate 4 is also arranged on the lower portion of the vertical stay rod, the prepared holes of the ear plates are aligned, the stay rod pin 6 penetrates through the prepared holes to fix the ear plates, and the middle stay rod 3 is in a free suspension state at the moment.
Step six: fixing the fixed end of the stay cable with a corresponding node of the upper latticed shell 1 through an ear plate, drawing the stretching end of the stay cable to a position 1m away from the node ear plate at the other end by drawing equipment, drawing the stretching end of the stay cable to be in place by utilizing equipment such as a hoisting belt, a jack and the like, and fixing the other end of the stay cable at the ear plate by using a pin shaft; two pull cables at each ear plate are sequentially installed in a clockwise direction; after the installation of the inhaul cable is finished, a second layer of long clamp plate 8 of a double-layer clamp plate type clamp node 14 is installed at the position of the marked node, and after the second layer of long clamp plate is in place, a nut 9 on the lower side of the first layer of long clamp plate is screwed to lightly clamp the first layer of long clamp plate 7 and the second layer of long clamp plate 8, but the inner layer of the clamped inhaul cable is allowed to slide; the toothed bulge of the third layer of long splint 11 is placed in the toothed groove of the second layer of long splint, and the toothed groove of the second layer of long splint is tightly clamped and attached to the toothed bulge of the third layer of long splint after the angle of the inhaul cable is adjusted by rotating the third layer of long splint, so that the node cannot rotate; the outer layer cable of the inhaul cable is placed at a cable groove of a third layer long splint 11, a bolt 13 is placed on the third layer long splint 11 in advance, a screw hole of a fourth layer long splint 12 is aligned with the bolt and is attached to the third layer long splint 11, at the moment, a nut is installed and is screwed down lightly, but the outer layer cable is allowed to slide along the cable groove, at the moment, all the inhaul cables in the cable truss structure are in a loose state and cannot bear external load, and the attached drawing 5 shows.
Step seven: and step seven, repeating the concrete steps of the step five and the step six until all the components are installed in place.
Step eight: tensioning each cable in a synchronous tensioning mode, wherein a tensioning counterforce device installed at a node is firm, reliable and easy to disassemble; during tensioning, the influence of the stay cable on the external upper latticed shell (1) is considered, the deformation of the upper latticed shell 1 is controlled in a symmetrical tensioning mode, the upper latticed shell is tensioned in batches in a fixed direction in three stages, the tensioning process is divided into three stages, the first stage is tensioned to 30% of the target cable force, the second stage is tensioned to 60% of the target cable force, and the third stage is overstretched to 105% of the target cable force to offset the prestress loss.
Step nine: after all the inhaul cables are tensioned, all the nodes are checked and finely adjusted, after the situation that the inhaul cables are correct is confirmed, the hexagon bolts are screwed down to clamp the first layer of long clamping plates 7 of the double-layer pressing plate type clamp 14, the vertical supporting rods 3 and the inhaul cables are fixed at the position of the double-layer pressing plate type clamp 14 and cannot slide, and installation is finished.
The foregoing is an exemplary embodiment of the present invention, and the practice of the present invention is not limited thereto.