CN103590603B - Large span multi-curvature shell structure of reinforced concrete method - Google Patents

Abstract

A construction method for a large-span multi-curvature thin-shell reinforced concrete structure. The specific construction steps include drawing drawings, making and constructing glass fiber reinforced plastics, cleaning the construction site, performing setting-out positioning according to predetermined curvature and contour line data, erecting support frames, and erecting thin-shell reinforced concrete structures. Shell structure support frame, making thin shell structure formwork, binding shell steel bars, pouring concrete and removing formwork support frame, etc., the present invention adopts the contour line method and control line to decompose the formwork to determine the specifications of the component glass fiber reinforced plastics, and realizes rapid erection. The construction time is saved; the part near the bottom of the shell adopts double-sided glass fiber reinforced plastic formwork, and the mold is sealed with spaced steel wire mesh, which ensures the vertical bearing capacity and solves the problem of large-slope concrete construction, effectively solving the problem of structural alignment The oblique thrust of the body; in addition, in the present invention, the concrete is poured symmetrically in sections to balance the force on the support system and solve the construction difficulties caused by the large shell area and steep slope.

Description

Construction method of long-span multi-curvature thin-shell reinforced concrete structure

technical field

The invention relates to a reinforced concrete construction method of a large-span multi-curvature thin shell structure, in particular to a construction method of an eggshell-shaped reinforced concrete structure.

Background technique

With the strengthening of my country's economic strength, people have put forward higher and higher requirements for the shape and space of buildings. The continuous development of architectural structure theory and the accumulation of large-scale engineering practice have led to the development of concrete structure forms from regular planes and straight spaces to special-shaped spaces, beautiful shapes, and high headroom. For space-shaped structures, choosing a reasonable and safe formwork support design method and advanced construction technology is the key to ensuring the quality and effect of the structure. Large-span, multi-curvature, and complex spatial structures are beautiful and majestic, and are increasingly favored by investors. However, at present, although the construction technology of high-rise buildings has reached a relatively high level, for such large-span, For space structures with multiple curvatures and complex shapes, especially cast-in-place reinforced concrete structures, there is still relatively little practice in the prior art, and the corresponding construction methods and processes are also very imperfect and mature. At present, glass fiber reinforced plastics are mostly used as multi-curvature structures. However, due to the many changes in curvature, the position positioning and height control of the vertical poles during the erection of the support frame are facing difficulties. Due to the relatively large span, the load-bearing capacity of the general FRP formwork cannot meet the requirements, and the curvature of the shell edge is large. Concrete Concrete slides easily during pouring. Therefore, there is an urgent need for a construction method for large-span multi-curvature thin-shell reinforced concrete structures with reasonable cost, simple operation, and high feasibility.

Contents of the invention

The purpose of the present invention is to provide a construction method for large-span multi-curvature thin-shell reinforced concrete structures, which solves the difficult problems in the construction of large-span multi-curvature thin-shell reinforced concrete structures in the prior art, such as the problem of determining the specifications of glass fiber reinforced plastics, and the large curvature changes. In the process of erecting the support frame, the position positioning and height control of the vertical pole are facing difficulties. Due to the large span, the load-bearing capacity of the general FRP formwork cannot meet the requirements, and the concrete is prone to slide when pouring the concrete due to the large curvature of the shell edge. question etc.

To achieve the above object, the specific implementation scheme adopted by the present invention is:

A construction method for a large-span multi-curvature thin-shell reinforced concrete structure, characterized in that:

Its construction specific steps include:

Step 1. Draw CAD construction drawings, and draw 3D model drawings through rhino software, and at the same time draw the floor plan layout of the support frame and the contour projection diagram of the shell;

Step 2. Make the component glass fiber reinforced plastics with specific curvature: Find the longitudinal central axis of the structure to be constructed on the 3D model diagram, and use the longitudinal central axis as the baseline to make a series of parallel lines with an interval of 1 to 3 meters on both sides as a control Line, the specifications and curvature data of the part surrounded by two adjacent control lines and two adjacent contour lines are used as the specifications and curvature data of the decomposed FRP, and the formwork manufacturer makes the component FRP according to the obtained data;

Step 3: Clean up the construction site;

Step 4, setting out positioning: measure the construction site and set out the positioning according to the plan layout of the vertical pole of the full house support frame and the contour line projection diagram of the shell, and mark the position of the contour line and the vertical pole;

Step 5. Set up the full support frame: set up the full support frame under the proposed thin shell structure, use fasteners to connect the vertical bar and the horizontal bar to form a frame body, the top of the vertical bar of the support frame is connected to the U bracket, and the U bracket is on top Connect the steel pipe keel with the same curvature as the thin shell, and add a wooden wedge between the U bracket and the steel pipe keel to plug the gap between the steel pipe and the U bracket;

Step 6. Make the thin-shell structure formwork: first, the formwork boundary line with an elevation of 1 to 2 meters is used. The part below the formwork boundary line adopts double-sided FRP formwork, that is, the bottom formwork and the top formwork are set up at the same time; the part above the formwork boundary line adopts Single-sided FRP formwork, that is, only the bottom formwork; the bottom formwork and top formwork of the double-sided FRP formwork of the thin shell structure are connected by anti-sealing bolts;

Step 7. After the formwork is installed, directly bind the steel bars in the middle of the formwork, including bending the steel bars according to the predetermined curvature, binding the steel bars of the hidden beams of the shell and binding the steel bars of the shell plates, and setting up intercepting steel wire meshes at intervals between the shell steel bars, and pouring concrete When intercepting the concrete drop;

Step 8. Concrete pouring: Use continuous layer pouring method, control the pouring thickness of each layer within 450mm, the interval between the upper and lower layers should not exceed the initial setting time of the concrete, and pour 50mm thick shell concrete evenly at the bottom before pouring concrete Cement mortar with the same mortar composition; when pouring the double-sided glass fiber reinforced plastic formwork part at the bottom, adopt the symmetrical cutting method on both sides; finally, manually vibrate and calender the surface, and the shell is formed;

Step 9, maintaining the shell formed by pouring concrete;

Step 10. Remove the support frame of the thin shell structure.

The specific operation of setting up the thin shell structure support frame in the step 5 is:

Step 1. Mark the location of the number rod layout on the floor plan of the vertical rod of the support frame in the whole hall;

Step 2. Arrange the number rods according to the layout diagram of the number rods;

Step 3. Determine the elevation of the middle vertical pole by means of pulling wires of adjacent scale rods, and saw the steel pipe of the vertical pole to make the height meet the requirements;

Step 4. Set up poles gradually from the left and right sides to the middle;

Step 5. Install the U bracket on the top of the pole;

Step 6. Check and calibrate the height of the pole;

Step 7, set up the cross bar;

Step 8, bending the steel pipe along the curvature of the thin shell structure to make a steel pipe keel, and making corresponding wooden wedges at the same time;

Step 9. Put the steel pipe keel on the top of the frame, tie it firmly with the U bracket with iron wire, and tie it with the crossbar 7 with iron wire, plug the wooden wedge between the U bracket and the steel pipe keel, and the support frame is completed.

Wherein, in the step 3, the number pole is not load-bearing, only the elevation control of the pole is carried out, and it is dismantled as it is erected. During the operation, every 4 to 8 columns of poles are used as a group. When the erection of the first group of poles is completed , remove the number rod used to control the elevation, and then start to arrange the next group of number rods, and set up the next group of vertical poles.

In the operation steps of the construction method of the large-span multi-curvature thin-shell reinforced concrete structure, the specific operation steps for making the thin-shell structure formwork in the step six are:

Step 1. Number all the templates to be installed with different curvatures according to the positions to be installed;

Step 2. Mark the template boundary line at the place where the height of the shell is 1-2 meters, that is, mark a contour line of a specific height as the template boundary line;

Step 3. Hoist the glass fiber reinforced plastic bottom formwork for the entire shell: install the bottom formwork from the top to both sides according to the number. It is necessary to ensure that the joints are tight. The joints of the formwork are pasted with sponge strips. The joints between the formworks are sealed with special materials. To prevent slurry leakage;

Step 4. Prepare the shell glass fiber reinforced plastic top formwork for the part below the formwork boundary line: in the part below the formwork boundary line, add a layer of glass fiber reinforced plastic on the outer surface of the completed single-side glass fiber reinforced plastic to become a double-sided glass fiber reinforced plastic formwork, and the double-sided glass fiber reinforced plastic formwork The bottom formwork and the top formwork are connected by pull water stop bolts;

Step 5. Calibrate the formwork: After the formwork construction is completed, the review work must be carried out, and the concrete can only be poured when the requirements are met.

As an optimal scheme in the operation steps of the construction method of the large-span multi-curvature thin-shell reinforced concrete structure, in the sixth step, welded steel bar heads are added to both sides of the pulling water-stop bolts as top supports.

As an optimal scheme in the operation steps of the construction method of the large-span multi-curvature thin-shell reinforced concrete structure, in the sixth step, the two ends of the anti-slip bolts are worn with frustum-shaped rubber plugs with anti-slurry effect, and the net of the two rubber plugs is The spacing is the thickness of the shell minus twice the thickness of the rubber plug. After the concrete is poured, the rubber plug will be removed, and an arc-shaped pit will be left on the wall. The pit will be filled with waterproof mortar with a higher grade.

As an optimal solution in the operation steps of the construction method of the large-span multi-curvature thin-shell reinforced concrete structure, in step 6, the front and rear edges of the bottom formwork are provided with flanging, and the height of the flanging is the same as the thickness of the shell.

Compared with the prior art, the advantage of the present invention is that: the present invention uses the contour line method with the control line to decompose the formwork to determine the specifications of the component glass fiber reinforced plastics, and at the same time quickly realizes the unification of the position and height of the vertical pole in the support frame so as to perform rapid erection. The construction time is saved; the double-sided closed formwork is used near the bottom of the shell to ensure the vertical bearing capacity; the spaced steel wire mesh is used to seal the formwork when the steel bars are bound, which solves the problem of large-slope concrete construction and effectively solves the problem. The oblique thrust of the structure on the frame is solved, and the problem of cold joints in the construction of the prior art is well solved; in addition, in the present invention, the concrete is poured symmetrically in sections, so that the force of the support system is balanced, and it solves the problem caused by the area of the shell. Construction difficulties caused by large and steep slopes.

Description of drawings

Fig. 1 is the construction flowchart of the large-span multi-curvature thin-shell reinforced concrete structure construction method of the present invention;

Fig. 2 is a schematic diagram of vertical poles and contour lines in the construction of an eggshell-shaped reinforced concrete structure according to an embodiment of the present invention;

Fig. 3 is the schematic diagram of formwork structure in the construction of eggshell-shaped reinforced concrete structure of the embodiment of the present invention;

Fig. 4 is a structural schematic diagram of an eggshell-shaped reinforced concrete structure according to an embodiment of the present invention.

Reference signs: 1-double-sided glass fiber reinforced plastic formwork, 2-pull water stop bolts, 3-water stop sheet, 4-steel pipe keel, 5-wooden wedge, 6-U bracket, 7-horizontal bar, 8-vertical bar, 9-shell, 10-formwork boundary, 11-contour line, 12-one-sided FRP formwork, 13-bottom reinforcement, 14-top reinforcement, 15-bottom formwork, 16-top formwork, 17-interception wire mesh.

Detailed ways

The eggshell-shaped reinforced concrete structure involved in the embodiment of the present invention is the exterior decoration structure of the gate. Design according to the reasonable service life of 50 years, the safety grade of the building structure is two grades, and the seismic fortification intensity is 8 degrees, as shown in Figure 4, the shell top elevation of the structure schematic diagram of the eggshell-shaped reinforced concrete structure of the present invention is 4.45m , the shell has a span of 42m, which is relatively large, and the surface curvature of the structure varies widely and irregularly, which makes the design and construction of the formwork difficult.

Fig. 1 is the construction flowchart of the large-span multi-curvature thin-shell reinforced concrete structure construction method of the present invention, and concrete construction method is as follows:

1 Draw construction drawings

Draw the 3D model diagram through the Rhino software, and at the same time draw the floor plan of the support frame pole 8 and the schematic diagram of the contour projection of the shell;

2 Make the component FRP with specific curvature

Specific steps are as follows:

1) Find out the longitudinal central axis and contour line of the structure;

2) Take the central axis as the baseline and make parallel lines with a distance of 2m to both sides as the control line;

3) Take the control line as the benchmark to make a vertical cut plane on the structural model, and the two arcs where the cut plane intersects with the structure are the bottom line and the top line of the structure;

4) The area between two adjacent control lines and two adjacent contour lines is the decomposed template model, and the intersection data of the four lines is the data of the four corners of the template;

5) According to the characteristics of contour lines and control lines, the specific data of each template can be determined.

6) According to the obtained data, the formwork manufacturer produces the finalized FRP formwork

3 Construction site cleanup

Before construction, the ground where the support frame is to be erected should be cleaned up, and the underplate of the support frame should be ensured to be evenly stressed.

4 According to the established curvature and contour line 11 data and lay out the positioning

Fig. 2 is a schematic diagram of vertical rod and contour layout in the eggshell-shaped reinforced concrete structure construction method of the embodiment of the present invention; Fig. 3 is a structural schematic diagram of the formwork in the eggshell-shaped reinforced concrete structure construction method of the embodiment of the present invention; In this embodiment, the computer model construction simulation technology has been used in the early stage of the project to obtain the specific data of the curvature and the contour line and combine the two to obtain the design value of the formwork. Schematic diagram of the plane of the high line, measure the construction site according to the diagram, set out the line and position, mark the position of the contour line 11 and the pole 8.

5 Set up the support frame

Set up a support frame: set up a protective operating frame on the roof of the basement, and the operating frame is set up around the gate. The vertical distance of the vertical poles is 1500mm, the row distance is 1000mm, and the step distance is 1200mm. Safety nets, dense mesh safety nets and skirting boards are added. The protective railing adopts the form of three railings. The sweeping pole is 50mm from the working surface, the middle railing is 500mm from the ground, and the upper railing is 1500 from the ground. The height exceeds the operating surface by no less than 1500mm.

6 Set up the support frame of the thin shell structure

The technical parameters of the support frame: the support frame adopts the fastener type steel pipe support frame system, the vertical and horizontal spacing of the vertical poles 8 should not be greater than 950mm, the step distance is 1200mm, the first horizontal bar is 300mm from the ground, and all support tops use U brackets 6, The steel pipe keel 4 is on the U bracket 6, and there is a wooden wedge between the two. The bottom of all the vertical poles 8 can be used as a short wooden square of 50×100mm as a skid, and the length is not less than 400mm. The skid is unified with the steel pipe keel 4 In the same direction. The spacing from the top support point to the last cross bar 7 is no more than 300mm. The crossbar of the support frame should be pressed tightly against the templates on both sides of the subsequent installation to prevent horizontal displacement.

The specific erection steps of the support frame: mark the arrangement position of the vertical pole on the floor plan of the support frame in the whole hall → determine the elevation of the middle pole 8 through the drawing of the adjacent vertical pole, and saw the steel pipe of the vertical pole to make it The height meets the requirements→set up the vertical pole 8 step by step from the left and right sides to the middle→set the U bracket 6 on the top of the vertical pole 8→inspect and calibrate the height of the vertical pole 8→set up the cross bar 7→bend the steel pipe along the curvature of the thin shell structure , make the steel pipe keel 4, and make the corresponding wooden wedge 5 at the same time → install along the steel pipe keel 4 and tie it firmly with the U bracket with iron wire, and tie it with the cross bar 7 with iron wire, and plug the wooden wedge 5 between the U bracket and the steel pipe keel 4 , the support frame is completed.

The gate structure has a large span and is an irregular eggshell shell 9, and the surface curvature of the structure varies widely and is irregular. Therefore, the positioning, measurement and setting out of the gate is the most important thing to ensure the construction quality of the entire project; the contour line of the gate The 11 projection line is an irregular arc, and the surveyor can only set out the line point by point, and then connect the line. The structure span of the gate shell is 42 meters. There are many projection points of the contour line 11 that need to be measured and set out, and the workload is extremely high. Large, requiring a large number of surveyors to cooperate; surveyors need to release the plane layout net of the formwork support system on the structural roof, and all support frame poles 8 need to be positioned on the structural roof. The workload is large and a large number of surveyors are required Cooperate with the operation; the shelf worker erects the crossbar 7 according to the step distance of the crossbar 7, and when the vertical pole 8 is erected to the height range required by the design, an adjustable U bracket 6 is placed on the top of the vertical pole 8 through the control of the pull wire of the adjacent leather number rod. And adjust to the design elevation; the support frame is set up from the left and right sides of the gate to the middle, and the number poles are not load-bearing, and should be controlled with the height of the poles 8 to be erected and dismantled; every five columns of poles 8 are a group, and when the first group When the five rows of vertical poles 8 are erected to the design elevation, remove the scale poles used to control the elevation, then start to arrange the second set of scale poles, set up the second set of poles 8, and so on; due to the structural span, the structural curvature Smaller, and the length of the steel bar is 9-12m, so it can be bound by manual bending along the surface of the formwork.

7 Make a thin shell structure template

Both the top formwork 16 and the bottom formwork 15 of the thin-shell structure formwork adopt prefabricated glass fiber reinforced plastic formwork. First, the elevation is 1.350 meters high. For the above part, only the bottom formwork 15 is provided, and A14 paired waterstop bolts are used between the top formwork 16 and the bottom formwork 15. The vertical spacing of the paired waterstop bolts is 350mm, and the horizontal spacing is 600mm. The bolts need to be welded with waterstops 3 , welded 50mm A14 steel bar heads on both sides of the waterstop screw as a top support, and put 25mm thick conical rubber plugs on both ends of the screw as anti-sludge caps when sealing the mold. After the concrete is poured, take out the rubber plug, and an arc-shaped pit will be left on the wall, and the pit will be filled with waterproof mortar with a higher grade.

The specific construction steps are: first, number all the templates to be installed with different curvatures according to the location to be installed; mark the template boundary line 10 at the place where the height of the shell 9 is 1.35 meters, that is, mark a contour line of a specific height as the template boundary line 10. Hoist the bottom formwork for the entire shell 9. 15: The formwork is installed from the top to both sides according to the number. It is necessary to ensure that the joints are tight. The joints of the formwork are pasted with sponge strips. The joints between the formworks are coated and sealed with special materials. Prevent grout leakage; set up the shell 9 top formwork 16 for the part below the formwork boundary 10; correct the formwork: after the formwork construction is completed, the review work must be carried out, and the concrete can only be poured when the requirements are met. The bottom mold of the front and rear edges of the housing 9 should be provided with flanging on one side of the structural edge, and the flanging height is the same as the thickness of the structural plate.

Formwork professional manufacturers and technicians design formwork and support system configurations, draw formwork arrangement diagrams, and number, process and install all formworks; for formwork support, arrangement, construction sequence and disassembly methods, the foreman must explain to the team members in detail Disclosure; the templates and accessories transported to the site should be counted and inspected one by one according to the specifications and quantities, and those that do not meet the quality requirements should not be used; the templates are sorted by number on the site and stacked in parallel, and the upper and lower templates should be placed between the upper and lower templates. The formwork is compressed and deformed; the outer formwork of the root of the shell 9 must be closed after the acceptance of the steel bars. Paste sponge strips on the seams to prevent grout leakage. After the formwork is completed, it must be reviewed and the concrete can only be poured when the requirements are met.

8 Binding of shell reinforcement

8.1 Rust removal of shell foundation beam reinforcement

Due to the long-term exposure of the steel bars on the construction site, the surface has different degrees of floating rust. In order to meet the requirements of the design and construction specifications, this part of the steel bars needs to be derusted to ensure the construction quality of the project.

According to the different floating rust conditions of steel bars, the following two methods are mainly adopted:

1) For steel bars with a lot of floating rust, use a rust remover to remove them;

2) For steel bars with little floating rust, use steel brush to remove them.

8.2 Steel bar processing

Reinforcement staff of the construction team is responsible for flipping the steel bars. A steel bar processing shed is set up at the construction site, and all steel bars are processed and bent at the construction site.

8.3 Binding of hidden beams at the edge of the shell and hidden beams at the bottom

Familiar with the drawings, clean up the bill of materials→sort out the steel bars used→clean up the operation surface→transport the steel bars in place→draw the spacing of the beam stirrups→place the beam stirrups→through the bottom longitudinal reinforcement of the beam→through the top longitudinal reinforcement of the beam→adjust the thickness and spacing of the reinforcement cover→ Check whether the protective layer of steel bars and the position of steel bars meet the requirements → clean up the on-site equipment and waste.

8.4 Binding of steel bars for shell plates

Familiar with the drawings, check the bill of materials → sort out the steel bars used → clean the formwork → mark the line on the formwork → ship the steel bars in place → tie the bottom reinforcement 13 → tie the top reinforcement 14 → adjust the thickness and spacing of the reinforcement protection layer → check whether the reinforcement protection layer and the location of the reinforcement are correct Meet the requirements → clean up on-site equipment and waste. Before tying the steel bars, the surface of the formwork must be brushed with a release agent. During the preparation work, focus on controlling the specifications and sizes of the steel bars, the thickness of the concrete pad, the size of the horse stool iron, the positioning bar of the wall column reinforcement, and the embedded iron parts, etc.

9 pouring of concrete

The strength grade of the concrete for this shell structure is C30, and the particle diameter of the concrete aggregate shall not be greater than the minimum thickness of the protective layer. When pouring, a car pump pours from the left and right sides of the gate to the middle.

Pre-arrange the location of the concrete feeding point and the number of vibrator operators. Before concrete pouring, pour 50mm thick cement mortar with the same composition as the concrete mortar of the shell evenly at the bottom. Concrete should be continuously poured in layers, and the pouring thickness of each layer should be controlled within 450mm. After vibrating and compacting, the material should be redistributed from the place where the material was cut first. The interval between the upper and lower layers should not exceed the initial setting time of the concrete. The weather conditions, concrete retarding time and other conditions are determined, and the general control should not be greater than 1.5h. Manual vibration is used, and B20 steel bars are repeatedly inserted and tamped. Since the shell 9 is an eggshell-shaped inclined roof, within the scope of pouring one-sided formwork, that is, the part with an elevation above 1.35m, when the shell 9 is concreted, in order to prevent the concrete from falling to a low place, the slump of the concrete within this range It is strictly controlled at 140±10mm, and at the same time, on the 9 steel bars of the shell, a steel wire mesh is set every 3m to stop the concrete from falling. The bottom closed formwork part is poured with A50 vibrating rod, and the material is symmetrically cut on both sides.

In order to control the structural surface elevation of the shell 9, before pouring concrete, within the structural scope of the one-sided formwork, a steel bar head is welded every 2m along the contour line 11, and welding is not allowed on the stress bars. The elevations of the structural surfaces of the casing 9 are the same. During the concrete pouring process, special personnel are assigned to take care of the formwork and check the support of the formwork at any time. In the process of concrete pouring for beams and slabs, it is not allowed to concentrate on one point of blanking, and it is not allowed to accumulate a large amount of concrete in one place. The concrete should be poured in a symmetrical way, and the uniform blanking should be maintained to avoid concentrating a large amount of load on one point and causing local failure. stable.

10 Remove the support frame of the thin shell structure after concrete curing

Formwork removal can only be started when the concrete strength reaches 100% of the design strength. It should be dismantled by number and block by block from top to bottom, and it is strictly forbidden to dismantle the upper and lower sides at the same time. Removal sequence: remove the top formwork 16 FRP → lower the U bracket 6 → remove the bottom formwork 15 FRP → remove the support system support frame.

(1) Before the steel bars are bound, the foreman should make a written technical disclosure to the construction team, and make further detailed disclosures to the operation team before the construction can be arranged. Clarify the specific requirements of the site: elastic line, the first steel bar on the side of the steel control line board is 50mm away from the concrete beside the beam, etc., the distance between the steel bar stool, the method of steel bar binding, the order of steel bar binding, the thickness of pads in different parts, the allowable deviation of steel bar binding, etc.

(2) Before binding the steel bars, the surface of the formwork must be brushed with a release agent, and some necessary preparations must be done in place, focusing on controlling the diameter and size of the steel bars, the thickness of the concrete pad, the size of the horse stool iron, and the positioning of the wall column steel bars Ribs, pre-embedded iron parts, etc.

(3) Construction materials and construction waste shall not be overloaded on the structure during the construction period.

11 Engineering quality control of long-span multi-curvature thin-shell reinforced concrete

The formwork installation must ensure that the position is accurate, the formwork joints are tight, the support system is firm and reliable, and no deformation or displacement occurs. After the formwork is installed, surveyors should check the formwork position, verticality, elevation, pre-buried and reserved hole positions, etc. The allowable deviation of the thin-shell structure formwork shall comply with the provisions in Table 1 below; when the steel bars are installed, the type, grade, specification and quantity of the stressed steel bars must meet the design requirements. For the position of the center line, it should be measured along the vertical and horizontal directions, and the larger value should be taken. The qualified point rate of the protective layer thickness of the longitudinally stressed reinforcement on the upper part of beams and slabs should reach more than 90%, and no more than The size deviation of 1.5 times the value in Table 2 or Table 3, Table 4 is the engineering quality requirements for concrete pouring.

Claims (7)

1. a large span multi-curvature shell structure of reinforced concrete method, is characterized in that:

Its Specific construction step comprises:

Step one, drafting construction drawing: draw construction drawing, and become 3D illustraton of model by rhinoceros Software on Drawing, draw full hall bracing frame vertical rod (8) layout plan and housing isohypse perspective view simultaneously;

The component glass fiber reinforced plastic of step 2, making specific curvature: find the length of structure to be onstructed to central axis on described 3D illustraton of model, using length to central axis for baseline does the parallel lines of a series of spacing 1 ~ 3 meter as control line to both sides, adjacent two control lines and adjacent two isohypses (11) are surrounded the specification of part and curvature data as the specification of glass fiber reinforced plastic after decomposing and curvature data, template producer according to must data creating component glass fiber reinforced plastic;

Step 3, construction plant cleaning;

Step 4, unwrapping wire are located: carry out measurement and unwrapping wire location to job site, the position of mark isohypse (11) and vertical rod (8) according to full hall bracing frame vertical rod (8) layout plan and housing isohypse perspective view;

Step 5, set up full hall bracing frame: set up full hall bracing frame in the below of planning to build thin shell structures, adopt fastener that vertical rod (8) and cross bar (7) are connected into support body, the top of the vertical rod (8) of bracing frame connects U holder (6), connect the steel tube framework (4) identical with shell curvature on U holder (6), described U hold in the palm to add between (6) and steel tube framework (4) timber wedge (5) jam-pack steel pipe and U hold in the palm between gap;

Step 6, making thin shell structures template: first absolute altitude is the template line of demarcation (10) of 1 ~ 2 meter high, and template line of demarcation (10) part below adopts bilateral glass steel form (1), namely sets up soffit formwork (15) and top template (16) simultaneously; Part more than template line of demarcation (10) adopts one-sided glass steel formwork (12), namely only has soffit formwork (15); Adopt drawing water-proof bolt (2) to connect between the soffit formwork (15) of the bilateral glass steel form (1) of thin shell structures and top template (16);

After step 7, model sheetinstallat complete directly in a template between assembling reinforcement, comprise according to determining curvature bending reinforcing steel bar, the dark beam steel of colligation housing and colligation shell plates reinforcing bar, between housing reinforcing bar, interception gauze wire cloth (17) is set up at interval, tackles concrete and fall during pouring concrete;

Step 8, fluid concrete: adopt continuous stratification pouring procedure, every layer of cast THICKNESS CONTROL is within 450mm, the interval time of levels does not exceed the concrete initial setting time, first in the thick cement mortar identical with housing concrete mortar composition of bottom even cast 50mm before pouring concrete; When pouring into a mould bottom bilateral glass steel form (1) part, adopt bilateral symmetry cutting mode; Also press polish of finally manually vibrating is wiped one's face, and housing (9) is shaping;

Step 9, maintenance is carried out to the housing (9) that concrete casting forms;

Step 10, dismounting thin shell structures bracing frame.

2. a kind of large span multi-curvature shell structure of reinforced concrete method according to claim 1, is characterized in that: the concrete operations of setting up thin shell structures bracing frame in described step 5 are:

Step 1, on full hall bracing frame vertical rod (8) layout plan, mark marked rod cloth set-point;

Step 2, according to marked rod arrangement diagram arrange marked rod;

Step 3, absolute altitude by adjacent marked rod span wire system determination intermediate uprights, carry out sawing to pole steel tube, make it highly meet the requirements;

Step 4, progressively set up vertical rod (8) from the left and right sides toward centre;

Step 5, vertical rod (8) top install U holder (6);

Step 6, vertical rod (8) is highly tested and calibrated;

Step 7, set up cross bar (7);

Step 8, the curvature of steel pipe along thin shell structures to be bent, make steel tube framework (4), make corresponding timber wedge (5) simultaneously;

Step 9, steel tube framework (4) is placed on frame top, asks (6) colligation firm with iron wire and U, and links with cross bar 7 iron wire colligation, U holds in the palm between (6) and steel tube framework (4) and fills in timber wedge (5), and bracing frame completes.

3. a kind of large span multi-curvature shell structure of reinforced concrete method according to claim 2, it is characterized in that: marked rod not load-bearing in described step 3, the absolute altitude only carrying out vertical rod (8) controls, with taking with tearing open, be one group with every 4 ~ 8 row vertical rods in operation, after the vertical rod of first group has been set up, remove the marked rod being used for elevation control, then start to arrange next group marked rod, set up next group vertical rod (8).

4. a kind of large span multi-curvature shell structure of reinforced concrete method according to claim 1, is characterized in that: the concrete operation step making thin shell structures template in described step 6 is:

Step 1, the template to be installed of all different curvature to be numbered according to position to be installed;

Step 2, be highly place mark template line of demarcation (10) of 1 ~ 2 meter at housing (9), namely marking the isohypse of a certain height is template line of demarcation (10);

Step 3, to whole housing (9) lifting glass fiber reinforced plastic bottom template (15): bed die is installed according to numbering from top to both sides, must ensure that piece is tight, sponge strip is pasted at formwork edge joint place, and the piece proprietary material between template smears sealing, with mortar leakage prevention;

Step 4, with lower part prepared by housing (9) glass fiber reinforced plastic top template (16) to template line of demarcation (10): in template line of demarcation (10) with lower part, one deck glass fiber reinforced plastic is added again at completed one-sided glass fiber reinforced plastic lateral surface, becoming bilateral glass steel form (1), adopting drawing water-proof bolt (2) to connect between the soffit formwork (15) of bilateral glass steel form and top template (16);

Step 5, template to be corrected: must check work after template construction, reaching requirement can fluid concrete.

5. a kind of large span multi-curvature shell structure of reinforced concrete method according to claim 1, is characterized in that: to drawing the both sides of water-proof bolt (2) to be welded with steel bar end as shoring in described step 6.

6. a kind of large span multi-curvature shell structure of reinforced concrete method according to claim 1, it is characterized in that: to the plug drawing the two ends of water-proof bolt (2) to be installed with the truncated cone-shaped of anti-slurry effect in described step 6, the clear spacing of two plugs is the thick thickness deducting twice plug of housing, plug is taken out after pouring concrete is complete, housing will leave arc pit, the higher leveled waterproofing mortar filling of pit label.

7. a kind of large span multi-curvature shell structure of reinforced concrete method according to claim 1, it is characterized in that: described in step 6, the sagittal edge of soffit formwork (15) arranges flange, the thickness of the same housing of flange height (9) is identical.