Section 1 Material incoming inspection Material quality is the basis of engineering quality. If the material quality does not meet the requirements, the project will not meet the standards. Therefore, strengthening material inspection is an important guarantee to improve engineering quality.
Article 1 Site material inspection procedure: 1. When the materials enter the site, the construction unit, supervision unit, construction unit, supplier and other relevant personnel shall participate in the on-site inspection. 2. The construction unit shall fill in the material entry inspection sheet, and attach the quality certificate and test report of steel and other materials to the supervision sheet. Article 2 On-site inspection contents: Visual inspection, actual measurement and other methods can be adopted. Mainly check whether the components are deformed (including deformation during transportation and welding deformation), whether the dimensions and specifications of the components meet the requirements of design drawings, and measure the galvanized thickness of the components with a coating thickness gauge. If there is any deformation, the construction unit must be required to correct it before installation, and the component shall not be corrected when the ambient temperature is lower than-16℃. The allowable deviation of component shape and geometric size shall meet the following requirements: component length: when L ≤ 5m 2mm; When l > 5m±3mm, the relative difference between the length of the member on the same floor and the mast chord is 65438±0mm；; The overall bending of the member is L/ 1000, and it is not more than 5 mm; The local bending is 1/750 of the measured length, and not more than 3 mm; The distance between the hole on the flange and the hole on a single flange is 0.7 mm; ; Hole spacing corresponding to each flange of mast or composite member: when the aperture is ≤ 21.5mm1.5mm+0.5mm, when the aperture is ≥ 26mm 2.0mm, the connecting plate of the connecting plate deviates from the plane 1.0mm, The connecting plate deviates from the bolt hole1.0 mm. The distance between any two holes or the distance between the hole on the node plate and the reference line is 65438±0.5mm, and the deviation of the crossbar or diagonal of the mast or composite member is 3.0 mm in the plane and out of the plane, in which the newly placed complex tower should pass the factory test and acceptance. In case of doubt about materials, sampling inspection shall be carried out according to relevant national standards, and the materials can only be used when the results meet the requirements of national standards and design documents. When using imported steel and substitute materials, it is necessary to provide the mechanical properties and chemical composition of the materials, and carry out sampling inspection, which can only be used after passing the design sampling inspection. Section II Acceptance of Tower Foundation The tower foundation shall be jointly accepted by the construction unit and supervision unit in conjunction with the civil construction unit, design unit and tower installation and construction unit. At the time of acceptance, the civil construction unit shall submit the following technical documents: design documents (including design change notice and material substitution certificate), material quality certificate or material reinspection report, concealed engineering records, concrete compressive strength experimental report, foundation concrete engineering construction records, civil foundation retest records and land rent test records (the land rent should be less than 5 ohms). The results of joint inspection and acceptance shall meet the design requirements and relevant national quality acceptance specifications. And check the data according to the basic acceptance data. The deviation between the position of the anchor bolt at the tower foot and the supporting surface of the flange shall meet the requirements in the table below. Allowable deviation of bearing surface, bearing and low-pin bolt: each allowable deviation is 1. Bearing surface (concrete pier) elevation ② ≤ h/1500; 11002 bearing surface (upper end face of flange) ① elevation ② levelness (upper end face of flange) 1.5mm 1/500 and not more than 3mm 3 torsion deviation of anchor bolt position (arbitrary cross section) 1.0mm 4 diagonal deviation of anchor bolt flange ≤ 1500 and < 10 mm (1 is diagonal distance) 5 The deviation between adjacent anchor bolts is ≤b/ 1500 and < 10 mm (b is tower foot span) 6 The length of anchor bolts protruding from the flange surface is a/kloc-0. When steel plates need to be padded, each stack shall not exceed three pieces. The gap between the bottom plate (flange) of the steel tower column and the foundation (the gap reserved for adjusting the horizontal height difference between the flange and the floor) should be compacted with fine stone concrete before the main load is loaded. Before installing the steel structure, the bolts exposed from the top surface of the foundation should be coated with anti-corrosion materials and properly protected to prevent the bolts from being corroded and damaged. The antiseptic material used is generally butter. Section III Inspection of Tower Installation Quality Article 1 Tower installation method: Before tower installation, construction personnel should carefully study the construction organization design or construction scheme. The tower can be installed by single-piece hoisting, extended assembly (single bar assembly combined with bar hoisting) and comprehensive installation, and when conditions permit, it can also be installed by integral hoisting. When expansion joint assembly is adopted, the strength and stability of deformable members should be checked by the fruit unit, and reinforcement measures should be taken when necessary. When the comprehensive installation method is adopted, its structure must be divided into several three-dimensional units, and all components of each system (unit) should have sufficient spatial stiffness and reliable stability after installation. When the integral lifting installation method is adopted, it must be approved by the design recalculation, and the auxiliary facilities and equipment should be calculated completely. When it is necessary to use the installed structure to hoist other components and equipment, the consent of the design unit should be obtained, and the strength and stability of related components should be checked, and reliable measures should be taken to prevent the structure from being damaged. Main components (tower column, cross bar, rigid diagonal bar, etc. ) determine the geometric position, should be hoisted to the design position, and preliminary correction and fastening before releasing the hook. After each layer of components is hoisted, they must be corrected according to the following table. When continuing to install the previous layer, the deviation value of the next layer should be considered. In order to ensure the safety of construction personnel, the construction is not allowed in the wind above level 6. Allowable deviation of integral and single-layer installation: each allowable deviation is 1. Verticality of the tower: ① overall verticality ② vertical deviation of two adjacent floors ≤H/ 1500≤H/750② horizontal height difference of the top surface of the horizontal flange of the tower column (horizontal height difference between adjacent tower columns in each section) ≤2mm≤ 1.5mm③ height difference of the horizontal tower beam of the tower platform ≤1/kloc-. Geometric tolerance of 0mm≤4mm750 4 tower section: when diagonal error D≤ 4m and D > 4m, and adjacent spacing error d≤ 4m and D > 4m, the cross-section difference of each layer of spherical grid is ≤ 2.00 mm ≤ 3.00 mm ≤1.50 mm ≤ 2.50 mm ≤ 5.00 mm, and the prestressed flexible diagonal bar and horizontal tension should be Pay attention to the influence of post-tensioned prestressed reinforcement on the stress value of prestressed reinforcement to prevent the reinforcement from twisting. The influence of light and temperature should be considered when prestressing. After prestressing steel bars, welding or heating shall not be carried out on or near steel bars. Flexible steel bars with the same section shall be prestressed at the same time. When testing and adjusting installed structural units, natural deformation caused by external environmental influences (such as wind, temperature difference and sunshine) should be considered.
Article 2 Quality control of flange connection: For nodes connected by flanges, the bonding rate of flange contact surface shall not be less than 75%. Check with a 0.3mm feeler gauge that the sum of the insertion depth and area is not more than 25% of the total area, and the maximum gap at the edge is not more than 0.8mm. When the flange gap exceeds 0.8mm, a gasket should be padded, and the gasket should be galvanized and treated with anti-corrosion. For joints connected by gusset plates, the bonding rate of the two surfaces of the contact surface should not be less than 75%. Check with a 0.3mm feeler gauge that the sum of the areas of the insertion depth should not be greater than 25% of the total area. The vertical inclination of the tower center should not be greater than11500 of the whole tower height. The torsion angle of steel tower shall not be greater than 0.65438 0 degrees.
Article 3 Installation requirements of antenna and feeder: the antenna bracket, suspension height and orientation shall meet the design requirements, and shall be firmly connected with the steel tower structure. The position and strength of the bridge feeder should meet the design requirements and should be firmly connected with the structural members of the steel tower. The flatness error of arch surface is ≤ 0. 15mm.
Article 4 Stair installation requirements: The steel stair treads shall be flat, and the inclination error shall be ≤ 2.00 mm. The upper and lower sections of the straight stair shall be connected with the vertical rod of the anchor. All railings shall be firmly connected with adjacent plates.
Article 5 Quality control of mast installation: single-piece hoisting, extended assembly (single-section or multi-section combination) and comprehensive installation can be adopted for mast installation, and integral hoisting can be adopted if conditions permit. Enlarging assembly and combined hoisting means checking the strength and stability of the deformation of components. When mast members are needed to support the lifting of mobile poles and other equipment, the strength and stability of mast members should be checked. And reliable measures should be taken to prevent parts from being damaged. Before installation, the fiber rope shall be tested according to the design requirements. When installing the mast, the fiber rope should be installed synchronously in time and pre-tensioned according to the design requirements. When hoisting the mast, temporary ropes should be added according to the installation load. The vertical inclination of the mast center should not be greater than H/ 1500 of the measured height. The horizontal distance error from the ground anchor of the rope to the center of the mast is ≤H/ 1500, and the included angle between the horizontal projections of the rope is ≤ 5 (degrees).
Article 6 Quality requirements for connection and fixation of components: The connection joints of various components must be inspected frequently before they can be fastened and welded. The connecting bolts of tower columns, cross bars, diagonal bars and main beams must be 100% perforated, and 2% of the bolts in the secondary part are allowed not to be perforated, but they must be repaired by electric welding. The weld strength should be equal to all bolts of the joint, and for high-strength bolts, it should be equal to the strength of missing bolts. The tower flange is locked with double nuts, and other bolts are locked with spring washers. The bolt penetration direction should be consistent and reasonable, and the exposed length after tightening is 2 ~ 3 buttons. Tighten the flange bolts symmetrically according to the fillet distribution angle; Tighten the connecting bolts symmetrically from the center to the edge. After fastening, effective measures must be taken to prevent bolts from loosening under tension and dynamic load. Quality requirements for welded components: When welding tower components, the project leader shall ensure that the welding process is operated by qualified workers. Welding is not allowed without effective protective facilities: strong wind (wind speed is greater than or equal to 10m/s), rain or snow; Relative humidity is greater than or equal to 90%. All on-site welds shall be inspected as Grade III welds, and welding materials shall be replaced by the factory. Welding shall be windproof, heat-insulated and degreased. Carry out rust prevention treatment after passing the inspection. After the tower is installed, it must be measured and corrected as a whole, and all the values must meet the acceptance specifications.
Article 7 Lightning protection measures for towers: towers should have perfect devices for preventing direct lightning and secondary induction lightning, and the introduction of lightning protection belts must comply with the design and relevant specifications. Generally, two lightning rods are led down from the top of the tower, and are reliably welded and fixed with the tower body, and reliable rust removal and anti-corrosion measures should be taken at the welding site.
Article 8 Warranty of tower installation project: The warranty period of tower installation is generally one year. After the tower is installed for one year, the verticality of the tower should be rechecked and corrected. After correction, the tower installation contractor shall cast exposed anchor bolts with fine stone concrete to prevent the anchor bolts from rusting.