How to ensure the safety of steel structure installation in rainy season?

Arrange special personnel to know the weather forecast in time and master the rainy weather data in advance. Arrange special personnel to inspect and manage the special projects on site before it rains. If the rainproof measures or measures are not standardized, the subcontractors shall be ordered to make rectification within a time limit, especially the lightning protection measures, which must be carefully and comprehensively inspected.

1. 1 Formwork rainproof measures

When the formwork is stacked, the lowest layer must be overhead from the ground to prevent rain immersion damage. In the template stacking place, there must be effective ground drainage measures to prevent rainwater deposition. Before it rains, the formwork and wooden back stare blankly must be effectively covered with plastic sheets in time. When constructing formwork in rainy days, beams and wall formwork must be provided with cleaning ports or water outlets. When it rains, cover the release agent with plastic sheets to prevent the isolation layer from being washed away by rain. The template isolation layer washed by rain must be repainted before closing the mold.

1.2 Rainproof measures for steel bars

Steel bars placed on site for a long time should be covered with rain to prevent serious corrosion of steel bars. Steel yard must have good drainage to prevent rain from soaking corroded steel bars.

In principle, the welding of steel bars should be stopped in rainy days. Under special circumstances, rainproof measures must be taken to prevent rain from wetting welded joints, which will change or reduce the mechanical properties of steel bars, thus affecting the processing quality.

1.3 concrete rainproof measures

Do a good job of pumping water in aluminum fluoride workshop, stop pouring concrete in case of heavy rain, leave construction joints in a reasonable position, do a good job of on-site drainage, and cover the poured concrete with plastic sheets in time to prevent changing the concrete mixture ratio, reducing the concrete strength grade and affecting the engineering quality. Before concrete pouring, the dirt and water in the formwork must be cleaned up before concrete pouring. Before concrete pouring, it is necessary to accurately grasp the weather forecast to avoid heavy rain during pouring, and sufficient rain-proof materials should be prepared at the site to cover it to prevent sudden rain during pouring. During construction in rainy season, the concrete mixing station is required to adjust the water consumption of concrete in time according to the actual moisture content of sand and gravel to ensure the quality of concrete. When pouring in rainy days, it is required to appropriately reduce the slump of the factory concrete.

1.4 rainproof measures for steel structures

In order to ensure the normal construction in the rain period and ensure the engineering quality. The main working procedures and climate-sensitive working procedures of this project should be based on the characteristics of rainy season construction, and corresponding technical measures should be worked out. High-strength bolts should not be installed in rainy days, and there should be no rain on the friction surface and high-strength bolts. When the rainy season is bad and the technical requirements cannot be met, the construction should be stopped. At this point, attention should be paid to ensuring the safety of the working face and setting necessary temporary reinforcement measures. In rainy season construction, it should be ensured that the construction personnel need rain gear. Pay special attention to construction electricity protection. When it rains, except in special circumstances, the aerial work should be stopped, the aerial workers should be evacuated to the safety inspection area, and the electric brake should be applied. L steel structure hoisting needs to hang facade net on the outside of the building, and protective railings should be set on the stairs, adjacent to the building and uncovered holes in the building. For the component to be hoisted, the water on the surface of the component should be cleaned first, especially the friction surface of the component, and the surface should be kept dry. If the wind force is greater than level 5, in rainy and foggy weather, stop the supporting process of high-altitude hoisting and installation; Such as welding, laying profiled steel plates, threading high-strength bolts and correcting structures.

1.4. 1 Welding of steel structure

Before construction, the operating platform should be tightly wrapped around the column at a height higher than the welding joint 1m, and the holes and joints on the platform plane should be tightly covered with asbestos cloth to prevent wind blowing and welding slag splashing. In principle, open-air welding is not allowed in rainy days. After butt welding, heat preservation should be strengthened to avoid brittle fracture caused by sudden drop of weld temperature. Wrap the weld around with asbestos cloth first, and then wrap it with rock wool. Welding machines, welding wires and gas cylinders should be placed in special sheds. So as to prevent the solder material from getting wet.

1.4.2 installation of high-strength bolts

Install high-strength bolts above level 5 wind, and stop operation in rainy and foggy weather. Before using high-strength bolts, the appearance of high-strength bolts should be checked, and there should be no corrosion and thread damage. If so, it should be repaired before use. Before operation, the moisture and impurities in the connector connection parts should be removed, and the connection surface should be kept clean and dry.

1.5 scaffold rainproof measures

Before and after the rain, the fasteners of scaffolding must be checked one by one, and the foundation of scaffolding must be checked first during the inspection. During the inspection, the construction and inspection personnel must ensure that their own safety protection measures are put in place, pay attention to anti-slip and fall prevention, and strictly prohibit illegal command.

1.6 temporary rainproof measures

The leakage protection devices of all kinds of electrical appliances must be sensitive, and all kinds of construction wires must be checked regularly. Insulation outsourcing must be intact to prevent rain leakage from hurting people. Outdoor electric welding machine, grinder, threading machine and other equipment should be equipped with a sunshade at the upper part and padded at the lower part to prevent rain soaking. The power cord shall not be erected with bare wires or plastic wires, and the distribution box must be rain-proof. The metal sheath of mechanical and electrical equipment must adopt reliable zero protection, and the leakage protection device of motor switch box should be reliable. Any mechanical operator must hold relevant certificates and wear insulating rubber shoes and gloves as required. In case of heavy rain, stop all electromechanical operations, and the main electrical box of the on-site steel processing plant must turn off the power supply. Check the safety performance of machinery and electrical appliances in time after rain. It is forbidden to hoist equipment and components and manually carry materials or equipment during heavy rain. Cables and wires used on site are strictly forbidden to get wet or laid on wet ground, and should be installed overhead or buried, with safe and reliable protection measures. Before the construction in rainy season, the power supply, electrical box, grounding and insulation of tower crane should be shaken and recorded. After the rain, all electrical equipment and electrical boxes should be inspected once, and the door of each electrical box must be closed and not opened.

2. Other safety measures

Anti-skid strips on the road should be tied firmly, and the anti-skid strips should be inspected and reinforced regularly to prevent people from accidentally falling up and down. Immediately after the rain, organize manpower to clean up the accumulated water in the field and roads. Special attention should be paid to the slippery scaffolding after rain, and the operators should pay special attention to anti-skid and anti-fall. Fences or warning signs should be set at the potholes to prevent people from slipping. The lightning protection device of the freight elevator on site must be checked regularly during the rain period. Site construction personnel, safety officers and technicians shall inspect the site regularly during the rain period, and handle the problems in time when found. The rainy season is sultry, so the logistics department should do a good job of heatstroke prevention and cooling for the construction personnel.

3. Health measures

Check all kinds of machinery before construction in rainy season, and set up oil pan as required to prevent the environment from being washed by rain. Clean up the garbage on site in time. If it can't be cleaned in time, it must be covered to prevent it from being washed away by rain. Toxic harmful waste must be collected in the garbage sorting room in time. Toxic and hazardous materials must be stacked in classified warehouses. In rainy days, steel bars and steel members are wrapped with plastic sheets. Attention must be paid to noise control during construction.