In order to better grasp the construction technology, mechanical combination, construction period and personnel allocation of capping beam project, the first capping beam project was specially constructed in the left picture of pier 64, and the construction pile number was K 107+776.82. The length of capping beam is 1 1.25m, the width is 1.85m, the height is 1.60m, and the axial spacing between two columns is 6.80m
Two. Project management objectives
The qualified rate of the first acceptance of the project quality in this bid section is 100%, and the unqualified project is not allowed, and the unqualified project is resolutely put an end to it. The Project Management Department promises to achieve 100% qualification rate at any time, whether it is self-inspection, sampling inspection or final inspection by the owner and supervisor, and strive for a good reputation.
Three. Construction arrangement and preparation
1. construction period: according to the site situation and construction organization arrangement, it is planned to start construction on 1 October 28th, 2009 and complete it on1October 30th. The planned construction period is 3 days, including bottom formwork installation1day, steel bar binding for 0.5 days, side formwork installation for 0.5 days and inspection for 0.5 days.
2. The service road in Dingcheng section of Changde City in this contract section has been completed, and the roads in the field are hardened with 40cm thick mud pebbles. The reinforcement site is hardened with concrete, and the reinforcement and its semi-finished products are piled up by the method of underlaying and covering.
3. Main material: the cement is P.O42.5 cement produced by Jidong Cement Co., Ltd.; Yueyang yellow sand is adopted; The crushed stone of Anjiagang in Dingcheng District of Changde City, the bar produced by Hunan Hualing Lianyuan Iron and Steel Co., Ltd. and the coil steel produced by Hunan Lengshuijiang Iron and Steel Co., Ltd. UNF-3A admixture produced by Shanxi Huangteng Chemical Co., Ltd. was adopted.
4. The concrete mixture ratio test was carried out. The design strength is 30Mpa, the 28-day strength reaches 40.2Mpa, and the design mix ratio is 392: 749: 1094: 196 (cement: yellow sand: gravel: water). The design slump is 8cm.
4. Construction organization and equipment
1. Construction organization system
The project management department has carried out a reasonable division of labor for the construction management personnel, and strictly controlled the construction progress and quality.
2. Mechanical equipment
(1) The construction team is equipped with 25t crane 1 set, 2 loaders, on-site traffic vehicles 1 set and 200Kw generator set 1 set.
(2) The concrete used shall be uniformly mixed and transported by the concrete mixing station in this contract. There are two 1000 forced mixers and three 10m3 concrete mixers in Hexi concrete mixing station of this bid.
(3) There are two cutting machines in the steel bar workshop, 1 cutting machine, 1 bending machine, 1 straightening machine and six electric welding machines.
(4) A set of capping beams, using the integral formwork with side ladle bottom. When making formwork, the block formwork and the capping beam formwork are designed and made as a whole.
Verb (abbreviation of verb) construction technology and scheme
(A) the construction process
First, measure and locate, then fix the hoop, place the bottom formwork, then tie the steel bar, install the side formwork, check after adjustment and inspection, and finally pour the concrete. The construction process is as follows:
Measuring and positioning → installing hoop → placing bottom formwork → steel bar binding → installing side formwork → inspection → concrete pouring → inspection.
(2) the main working procedure construction scheme
1. Measuring unreeling
Before capping beam construction, set the center point on the top surface of the column with surveying GPS, with the allowable deviation of 10mm, measure the elevation of the top surface of the column with a level, and install the template after being reviewed by the technical director and the supervisor.
2. Steel bar construction: the steel bar is formed by bone mould near the pier, and then hoisted in place by crane. The steel skeleton needs to be reinforced to facilitate hoisting.
3. Template construction
(1) The formwork of pier capping beam adopts large composite steel formwork, and adopts the structural form of side wrapping bottom.
(2) Place a steel hoop (500mm high in a single layer) at an appropriate height of the column, place two 36a-shaped I-beams on the hoop, tile channel steel or square timber on the I-beams, and lay a bottom die on the channel steel or square timber.
(3) After the steel skeleton is formed, erect the side formwork. Large composite steel formwork is used for the side formwork, and 10[ channel steel, spacing 100cm] is used for the rear flange. Back stare blankly up and down set φ 16 to bolt, brace on both sides of the template.
Construction guarantee measures of intransitive verbs
1. Quality assurance measures
(1) organizational guarantee measures
(1) Establish and improve the quality management system, and form a quality management network consisting of the construction director, the quality inspector, the construction team leader and team members, vertically and horizontally with the construction, technology, quality inspection, materials and other departments. Formulate and improve various quality management systems and post responsibility systems, and implement a one-vote veto system for all quality personnel; ② The construction of each working procedure shall be carried out in strict accordance with the design drawings and construction specifications, and the "three inspections" system shall be implemented; (3) Implement a graded technical disclosure system, so that the construction technical scheme of each working procedure can be known fairly well; (4) Carry out model project construction, sum up experiences and lessons in time, and ensure that the construction technology is feasible, the quality is safe and reliable; ⑤ Establish a technical review system to ensure that the measurement and setting-out, test and data filling are reviewed, so as to find and solve problems in time; ⑥ Formulate quality reward and punishment measures, constantly encourage and improve employees' sense of excellence in various forms, and strengthen employees' technical and quality training.
(2) Technical guarantee measures
(1) Reinforcement: a. Hardening treatment shall be carried out at the reinforcement processing and storage site; B, raw materials and semi-finished steel bars stored in the open air are covered with rain cloth; C. If the exposed reinforcement of the constructed structure is exposed for too long, measures should be taken, such as outsourcing plastic film or covering it with rain cloth as a whole; D. Corroded steel bars must be thoroughly derusted before being used in structural construction, and seriously corroded steel bars should be treated as waste and not used; E resolutely refuse to use inferior steel bars or unqualified steel bars, and use 506 covered electrode for steel bar welding.
(2) Concrete: A. Strictly control the raw materials of concrete, and resolutely do not use unqualified materials, and the incoming materials can only be used after being inspected by the supervision engineer; B. Mix concrete in strict accordance with the mixture ratio, and adjust the construction mixture ratio in time according to the material situation; C. Strengthen specimen production during concrete construction, with no less than 2 groups per shift. After the completion of concrete construction, cover or spray water for maintenance in time; D. check the slump at least 3 times per shift.
2. Time limit for a project guarantee measures
(1) Optimize the construction scheme, arrange the construction reasonably, and alternate with flowing water construction; (2) Strengthen the safety and quality control in the construction process, and regard safety and quality as the first factor to ensure the construction period; (3) When preparing the construction operation plan, fully consider the construction interference and unexpected factors in rainy days, increase the material supply and reserve, and submit the quality inspection in time; (4) Equipped with sufficient mechanical equipment, construction management personnel and on-site construction personnel; ⑤ Invest enough manpower and material resources to eliminate construction interference and create a good construction environment; ⑥ Prepare the generator set, ensure power failure without stopping, arrange night lighting, organize construction day and night, and the technical and quality inspection personnel are on duty day and night; ⑦ Arrange site drainage facilities, cover the work shed, prepare enough raincoats, rubber shoes and rain-proof cloth, set up electrical rain-proof devices, and make preparations for construction in rainy season to ensure uninterrupted rainy season.
refer to
[1] Zhong Xiaohui. Application of embedded support in the construction of capping beam of high pier of a road and bridge [J]. Guangdong Civil Architecture, 2004.438+02
[2] YANG Yabing, LIU, Optimal design and construction of prestressed capping beam substructure [J]. Chinese and foreign highways, 2004.04