This project is a commercial and residential building project of Hongyang Garden in Tangshan City, located on the west side of Torch Road in Tangshan City. Prepared by Tangshan Hongyang Real Estate Development Company through bidding, Tangshan Guo Wang Construction and Installation Co., Ltd. won the bid. The construction period is 333 days, and it is required to start on June 1+00, and be completed and delivered on October 30, 2002. The project is designed by Tangshan Planning and Architectural Design and Research Institute, and the building plane is a 5-unit combined strip residential building. The building area is 16757.66M2 (including basement area of 23 10M2). The basement is one and a half floors, and the main body on the ground is six floors. The basement is 2.2M high, the first floor is 3.6M high, the second floor is 3.0M high, and the third to sixth floors are 2.9M high. Huxing combination is one staircase and two households, the first and second floors are commercial and the third to sixth floors are residential. The project is a frame structure. Scaffold erection scheme is based on Technical Specification for Safety of Fastening Steel Pipe Scaffolding in Building Construction (JGJ 130-200 1), Safety Inspection Standard for Building Construction (JGJ59-99), Detailed Rules for Implementation of Safety Inspection Standard for Building Construction in Hebei Province and drawings.
Second, the scaffold material requirements
1) All kinds of scaffolding bars are welded steel pipes of No.3 steel, with an outer diameter of 48mm and a wall thickness of 3.5 mm. The products qualified by the manufacturer are used and have certificates of approval, and their mechanical properties should comply with the provisions of Q235A steel in the current national standard "Carbon Structural Steel" GBT700. The length of steel pipes used for vertical rods, main rails and diagonal rods is 4-6m, and the length of small rails and Rachel rods is 2. 1.
2) Fasteners shall use the qualified products of the manufacturer and hold the product certificate. The technical performance of fastener forged cast iron meets the requirements of Steel Pipe Scaffolding GB15831-1995. All fasteners used shall be inspected, and there shall be no defects such as air holes, sand holes, cracks and slippery threads. The joint surface between fastener and steel pipe should be strictly shaped to ensure good contact with steel pipe fastener. When the fastener clamps the steel pipe, the minimum distance at the opening should not be less than 5mm, the movable parts of the fastener can rotate flexibly, the gap between the two rotating surfaces of the rotating fastener should be less than 65438±0mm, and the fastener should not be damaged when the tightening torque of the fastener bolt reaches 60n * m..
3) The scaffold board shall be made of larch, with a thickness of 50mm and a width of 300 mm, and it shall not be used if it is decayed, twisted, twisted, broken or has a large transverse scab. The scaffold board used is 8cm at both ends, and it is wrapped with No.8 lead wire hoop for 3 times.
Three, scaffolding technical measures
1, construction preparation
(1) Before the scaffold erection, the technical director of the construction site shall make a written technical disclosure to the professional team leader paragraph by paragraph according to the scaffold erection plan, and perform the disclosure signing procedures, with each party holding one copy and supervising each other. The professional team leader shall make technical disclosure to the operators before the shift, and make disclosure records.
(2) According to the requirements of various materials used in scaffolding, all materials used should be inspected and accepted before they can be used on site. After entering the site, it should be classified and neatly stacked, and used for listing.
(3) Scaffolding operators must be trained by the labor department and hold relevant certificates.
2, the basis of scaffolding
(1) Before scaffold erection, the foundation shall be leveled and compacted, and there shall be no water around the scaffold foundation. A drainage ditch shall be set at 0.5 meters outside the scaffold external pole. Set a puddle at the lowest point, water flows into the puddle, and the water is discharged by submersible pump. The slope of the drainage ditch is 3-5‰. In order to ensure the bearing capacity of the frame foundation, the backfill soil of the foundation groove must be compacted layer by layer before the scaffold foundation can be made.
(2) After the backfill soil is compacted, a 0.2×3m wooden scaffold board with a thickness of 50mm is laid on it, and then a steel base is placed on the wooden scaffold board, and a vertical rod is placed on the steel base. After that, pay-off positioning shall be carried out according to the designed vertical pole spacing, and the wooden scaffold board shall be laid smoothly and shall not be suspended.
3, scaffolding structure technical requirements
(1) According to the requirements of scaffold structure, this project is a frame structure with internal and external double bent frames. The inside of the scaffold is 200mm away from the wall, the column is 450mm below the cornice, the outside column is out of the wall 1.2m, the column row spacing 1.2m, the vertical distance of the column 1.8m, and the step distance of the main rail is 65438. The upright post and the main rail are connected by straight fasteners. During erection, the vertical pole should be erected on the outside of the main rail, and the joints of two adjacent rails should be staggered by one step, and not less than 500mm. The distance from the center of each joint to the main node should not be greater than 1/3 step. Erection of poling should be vertical and horizontal, the verticality of poling should be 1/400, the total height should not exceed 50mm, the main rail should be horizontal, the total horizontal difference should not exceed 20 mm, the vertical distance deviation of poling should not exceed 20 mm, the length of small rail extending laterally from the frame should be 140mm, and the distance between small rail and main node should not be greater than 65430 mm
(2) For Rachel of the frame and the building, the height of the frame should be tied with short steel pipes and building columns on each floor, and the scaffolding with Rachel poles inside and outside should be fastened with fasteners and vertical poles or main rails. The vertical height of the tensile joint is not more than 4m, the layer-by-layer tensile joint and the horizontal spacing are not more than 6m, and one tensile joint is set every other concrete column. When setting, it should be as close as possible to the master node, and the distance from the master node should not exceed 30cm. The layout form adopts flower rows.
(3) The bracing is set with 6m steel pipes, with 7 uprights and 7 crossbars as a set of bracing, and every 6 sets of bracing at a 45-degree angle with the ground. The corners at both ends of the scaffold are set on both sides, and each set of bracing should be set continuously from top to bottom. In addition to fastening both ends of the diagonal bar with rotating fasteners, two fasteners should be added in the middle, and the distance between the fasteners at both ends of the diagonal bar and the vertical railing node should not be greater than 150. At the bottom of the diagonal and vertical rod connection point distance is not more than 200mm, bridging lap length is 1000mm, with three fasteners, fasteners at the end of the steel pipe is not less than 10cm. The lower end of the scissors must touch the ground.
(4) The scaffold of the construction operation layer must be paved, stable and strict, and the distance from the wall shall not be greater than 200mm. Scaffolding boards shall be laid between the upright post and the wall surface, and there shall be no gaps and head control panels. Only one operation layer is considered in the top-down construction of this project. For scaffolding laid by opponents, two small bars must be set below the joint, and the plate end is at the corner from the small bar150 mm.
(5) In order to protect the operation floor and the access opening, two protective railings shall be set at the height of 1.2m of the operation floor, but a dense mesh net with a license shall be hung, and the side ropes of the net shall be tied tightly with the main rail, and the skirting board with the height of 180mm shall be replaced with a wooden skirting board. Set a layer of pocket net at a distance of 3m from the ground, and set a safe passage at the south side of the building, with a length of 3m and a height of 3m, which is the same as the width of the hole. The upper layer is paved with a layer of 50mm wooden scaffolding, and signs are hung.
(6) Sealing method between scaffold and building: the federated eye network is vertically closed, and the quality requirements of federated eye network: ① The federated eye network should have four certificates and be flame retardant, and its continuous burning and smoldering time should not exceed 4 seconds. Comply with GB 16909. ② There are more than 2,000 meshes per10cm×10cm =100cm2. Permeability test of dense mesh net: When conducting the permeability test, lay the net flat at an angle of 30 degrees with the ground, and 3 meters above its center, use a 5KG steel pipe (pipe diameter 48-5 1mm) to freely fall vertically. If it does not penetrate, it will be a qualified product. Binding method of dense mesh wind: use 14# lead wire to bind the dense mesh net on the column or main rail to make the net firmly connected with the frame. The material of the fly should comply with GB 16909. Bag net sealing: use big eye safety net (flat net) to seal scaffolding and buildings, and set flat net on the second floor, once every10m.
(7) Scaffolding passage: Scaffolding body shall be provided with safety rails: ① The rail width shall not be less than 1m, and the slope shall be 1: 3 (height: length). (2). The spacing between the vertical pole and the horizontal pole should be suitable for scaffolding, the foundation should be treated according to the requirements of scaffolding, and the facade should be set with scissors. (3) The spacing between the small bars on the pedestrian ramp should not exceed1.5m. (4) When scaffolding is spread, anti-skid strips should be nailed on the board, and the anti-skid strips should not be greater than 300 mm..⑤ (5) A guardrail should be set, with an upper protective railing of 1.2m and a lower protective railing of 0.6m from the scaffold board, and a width of 180mm should be set at the same time.
(8) scaffold unloading platform: the unloading platform shall be marked with the control load; Construction should be carried out in strict accordance with the erection plan.
Design and calculation of unloading platform
The transverse distance of the vertical pole is b = 1m, the longitudinal distance of the vertical pole is l = 1.5m, and the step distance is h =1.5m..
Scissors are arranged continuously, and the width of the discharging platform is c = 2m.
(1) strength calculation
Mmax=q 12/8
q= 1.2(GK。 c+GH)+ 1.4 qqk . c
GK- scaffold board weight GK=0.3KN/M2.
C —— the width of the discharging platform C=2M.
GK- unit length of steel pipe GK = 38n/m
Kq- construction live load KQ= 1.2N/M2.
Qk- standard value of construction load QK=2000N/M2.
q = 1.2 *(300 * 1.0+38)+ 1.4 * 1.2 * 2000 * 1 = 405.6+3360 = 3765.6n/M
mmax =(3765.6 * 12)/8 = 470.7n . m
Check bending strength
s = Mmax/W = 470.7/5078 = 92.7n/MM2 & lt； 205 North /MM2
Therefore, the safety meets the design requirements.
(2) Calculation of deformation
Look-up table φ48*3.5 steel pipe parameters.
E=2.06* 105N/MM2 (elastic modulus of steel pipe)
I= 12 190mm (moment of inertia of steel pipe section) w/b = 5ql3/384ei = (5 * 3765.6 *10003)/(384 * 2.06 *105).
= 0.19% =1/5261150 meets the requirements.
Structural calculation meets the requirements of strength, stiffness and stability.
(9) Erection sequence of external scaffold
Scaffolding in this project is erected from bottom to top. After the poling pad is finished, scale out from one side of the building and draw the poling axis on the pad with chalk. Then put the standard base and sweeping bar on the base plate-> vertical bar (and then fasten the vertical bar and sweeping bar with right-angle fastener)-> install sweeping bar-> install the first step putlog-> correct vertical bar-> set the first row of pull nodes-> install.
Four, scaffolding inspection and acceptance
During installation, disclosure shall be made according to the construction progress; During inspection and acceptance, installation and acceptance shall be carried out in stages according to the progress; After the acceptance, it can be delivered for use and submitted to the scaffold for signature. Scaffolding shall be accepted by the competent foreman, technician, scaffolder, team leader and full-time safety officer.
Five, scaffolding use, maintenance, maintenance technical measures
1, the scaffold shall be inspected by designated personnel every day to check whether the columns and plates are sinking or loose, whether the fasteners of the frame body are slipping or loose, and whether the parts of the frame body are complete.
2, completes the scaffolding foundation drainage, after the rain to conduct a comprehensive inspection of scaffolding frame body foundation, it is forbidden to scaffolding basement water sinking.
3. The operating layer construction load shall not exceed 270KG//m2, and the cross bar support and cable wind rope shall not be fixed on the scaffold. It is forbidden to hang heavy objects on scaffolding.
4. It is forbidden for anyone to dismantle any parts on the scaffold at will.
5. In case of gale, fog, heavy rain and heavy snow with magnitude 6 or above, scaffold operation should be suspended, and operation can be continued only after inspection.
Six, scaffolding matters needing attention
1, steel pipes with an outer diameter of 48mm and 5 1mm are strictly prohibited to be mixed.
2. At the master node, the distance from the center line of fasteners such as fixed horizontal bar or vertical horizontal bar, bracing and lateral support to the master node is not more than150 mm. ..
3. The length of each rod end protruding from the edge of the fastener cover plate should not be less than 140mm.
4. The opening of the butt fastener should face the inside of the shelf, with the bolt facing up and the opening of the right-angle fastener not facing down to ensure safety.
5, shelf homework personnel must hold relevant certificates, wear safety helmet, fasten your seat belt.
6, in strict accordance with the erection scheme construction; Even the wall and bracing should be set in time, and shall not lag more than two steps.
7, in the process of erection, should pay attention to adjust the verticality of scaffolding, the maximum allowable deviation is100 mm. 。
Seven, scaffolding material dosage plan
Material Name Unit Quantity Entry Time
After the T 20 foundation of scaffold pipe is backfilled,
After backfilling the foundation of 1500 with right-angle fasteners,
400 After the foundation of docking fastener is backfilled.
After the rotary fastener foundation is backfilled for 500.
After the foundation of scaffold 1270 is backfilled,
After backfilling 900 dense mesh nets 1.8×6M.
After the flat screen 2×3M 240 slab foundation is backfilled,
Eight, scaffolding plan, elevation