When the diameter of the full-length reinforcement on the upper part of the frame beam is inconsistent, the full-length reinforcement between different straight diameters is overlapped by welding.
1) Process principle: straight thread reinforcement connection is a mechanical connection joint that can withstand tensile and compressive forces.
Operators: carry out technical disclosure and technical training for operators according to their process requirements.
The form of hooks shall meet the design requirements.
The material personnel of the project department and the on-site construction personnel shall check the appearance quality of steel, and check the quantity, diameter and size of steel.
3) Process flow: acceptance of threaded sleeve → breaking and cutting of reinforcement → inspection of diameter with outer diameter caliper → rolling on the cut flat end → inspection of thread with thread ring gauge → putting on protective sleeve → screwing in and installation with wrench on site → joint inspection to see whether it is screwed in place.
（3） The vertical transportation of reinforcement materials in the project is mainly carried out by tower crane.
（5） In order to ensure the position of the upper reinforcement of the floor slab, the reinforced horse stool is adopted.
（1） The shape and size of reinforcement processing must meet the design requirements.
Then place the reinforcement on the grinding wheel cutting machine and cut the head by 0.5 ~ 10mm to achieve flat end..
The production shall be carried out in strict accordance with the size, form and quantity of the reinforcement material list.
Finally, the material personnel of the project department shall sign on the acceptance sheet and make a qualified mark before it can be transported to the site for installation.
The material of threaded sleeve must have sufficient strength and comply with the technical conditions for high quality carbon structural steel (gb699-2015).
After fabrication, hang up signboards by categories and stack them neatly.
When the on-site reinforcement foreman receives semi-finished products, the person in charge of the reinforcement processing workshop shall make detailed records, handle the distribution and handover procedures, control the quantity of materials received, and avoid repeated material requisition, resulting in steel waste.
The length of straight section of hooks shall not be less than 10 times the diameter of reinforcement.
（2） Reinforcement stacking: after the reinforcement is transported to the construction site, it shall be stored in strict accordance with the batch, grade, brand, diameter and length, and the quantity shall be indicated to avoid confusion, and shall not be stacked together with acid, salt, oil and other items.
In the process of construction, the base metal and joints on site shall be randomly sampled and submitted for inspection together with the owner and the supervisor according to relevant regulations to ensure the stability of steel quality.
After the preliminary inspection is qualified, it shall be reported to the supervisor’s on-site personnel for acceptance.
180 degree hook shall be made at the end of grade I reinforcement, and its arc bending diameter shall not be less than 2.5 times of reinforcement diameter D, and the length of straight part shall not be less than 3 times of reinforcement diameter D.
Among them, the number of straight thread connection joints is large and the quality requirements are high.
The main parameters such as heat treatment status, pitch, profile height, profile angle, nominal diameter and thread tolerance shall comply with relevant regulations.
4) Operating points: ① steel bar end cutting: check whether the processed steel bar meets the requirements.
Account shall be made for the use of incoming reinforcement, and the use of reinforcement shall be tracked and recorded.
2) Construction preparation construction machines and tools: reinforcement straight thread threading machine, rounding equipment, gauge, wrench, grinding wheel saw, grinder, grinding wheel machine, etc.
The straight thread reinforcement connection process is mainly described.
（5） Reinforcement straight thread connection: the reinforcement joints of the project are connected by four connection modes: straight thread connection joint, flash butt welding joint, electroslag pressure welding joint and lap joint.
1、 Basic reinforcement scheme (I): according to the site conditions of the project, the reinforcement is processed in batches in the site, and the reinforcement processing site and reinforcement stacking site are also adjusted in time with the project progress.
（4） The allowable deviation of reinforcement processing is: the net size of the stressed reinforcement along the length direction is ± 10mm; The bending position of bent reinforcement shall be ± 20mm.
（1） Reinforcement mobilization and process inspection: when entering the site, the factory certificate of this batch of steel shall be provided, and the base metal shall be sampled and submitted for inspection.
Oil stains, paint stains and rust shall be removed before use.
They can work only after passing the examination and holding an employment certificate; Material: ① the connected reinforcement shall meet the reinforcement standard; ② Material of straight thread connecting sleeve: provide qualification certificate of connecting steel sleeve and verification certificate of torque wrench.
When mechanical connection is adopted, the frame strut Grade I joints are adopted for frame supported beams (including transfer beams such as frame supported beams), and grade II joints are adopted for other special marks.
The bending diameter shall be greater than the diameter of stressed reinforcement and not less than 2.5 times the diameter of stirrups.
See ⑥ reinforcement support for the specification and spacing of the horse stool reinforcement.
2、 Raw materials of reinforcement: raw materials of reinforcement of the project are purchased by the material Department of our company through unified bidding and processed on site (stirrups and some plate reinforcement are outsourced semi-finished products).
Its process is to first process the connection end of reinforcement into straight thread with a special threading machine for straight thread reinforcement joint on the construction site, and then tighten the reinforcement and the connection sleeve with pipe wrench through the straight thread connection sleeve.
The steel bar is processed by cutting machine to ensure that the end is flat and the structure is not damaged.
Reinforcement with granular or flake old rust shall not be used.
（2） When the end of the reinforcement is bent, the bending diameter shall not be less than 4 times of the reinforcement diameter D, and the length of the straight part shall be determined according to the design requirements.
3、 During the fabrication of reinforcement, the setting out shall be carried out according to the material list, and the batch production can be carried out only after the trial production is qualified.
（3） Material custody: the reinforcement shall be managed by a specially assigned person, and a strict management system of acceptance, storage and receipt shall be established.
The surface of reinforcement shall be clean and free from damage.
There shall be no harmful gas near the reinforcement stacking place to avoid corrosion of the reinforcement.
（2） In this project, the reinforcement with stress diameter greater than or equal to 12 and less than 22 is connected by welding or mechanical connection, the reinforcement with stress diameter greater than or equal to 22 is connected by mechanical connection, and the reinforcement with diameter less than 12 can adopt binding lap joint.
（3） The ends of stirrups in the project shall be provided with hooks.
（4） The reinforcement mesh on the upper floor of the basement floor of the project adopts φ 20 reinforced horse stool shall be erected with a spacing of 1500mm and arranged in quincunx; Tie bars are made of φ 12@800 Quincunx setting.
