Kneel for construction safety measures plan in high temperature season

A, hot weather operation safety precautions

1. Arrange work and rest time reasonably, avoid high temperature period, and pay close attention to construction when the weather is cool in the morning and evening.

2. Wear safety helmet in strict accordance with the requirements of outdoor high temperature operation in summer.

3. Employees should learn the knowledge of safe construction in summer and master relevant prevention and protection skills.

4. In the closed (semi-closed) space of high temperature workplace, appropriate measures should be taken to do a good job of ventilation and cooling to avoid heatstroke.

5. In hot weather, pressure vessels should avoid high temperature and sunshine.

6. Pay attention to personal hygiene in high temperature in summer and don't eat unclean food; Prevention of mosquito bites and seasonal diseases.

7. The construction weather is hot in summer, and there are many cases of wearing slippers to work shirtless. This situation should be strictly prohibited, and the inspection on the correct use and wearing of labor protection articles should be strengthened.

8. Fire prevention measures should be taken in summer construction, and oxygen acetylene bottles should strictly abide by safety operation procedures and do a good job of preventing exposure.

Second, the steel structure

1. It is forbidden to pile steel bars at will, and transportation and stacking should be arranged in a unified way.

2. Waterproof and rust-proof measures should be taken in the steel processing plant and semi-finished product stacking place on the construction site.

3. When stacking, wood should be placed above the bottom mat to prevent water from rusting the steel bars.

4. Cover the reinforcement with geomembrane in rainy days, and check whether the geomembrane leaks.

5. It is strictly prohibited to pile up on the excavated plain soil, so it is easy to make the square wood fall into the soil, make the steel bar in direct contact with the soil, and cause the steel bar to rust.

6. During outdoor construction in summer, it is forbidden for workers to touch steel bars directly with their bare hands when handling steel bars, so as not to cause burns.

7. When steel binding, take protective measures.

Third, the construction template

1. When construction templates are stacked in summer, fire-fighting equipment should be placed in the site to avoid fire caused by dry temperature.

2. When materials are piled up in a centralized way, personnel shall be arranged to carry out special inspection, and there shall be no open fire at the site.

3. Construction templates, beam and wall templates must have cleaning ports or water outlets, and the template release agent should be covered with plastic sheets in case of rain after painting to prevent the isolation layer from being washed away by rain.

4. If the steel pipe frame material is supported on the backfill soil, sleepers and pads should be well padded. Check the firmness, stability and section size of the formwork in time after the rain.

5. Wooden formwork used in rainy days should be dismantled and leveled to avoid deformation and cleaned up in time. Brush the release agent again after the heavy rain.

6. After the template is assembled, concrete should be poured as soon as possible to prevent the template from being deformed in the sun and rain. If the formwork cannot be poured in time after assembly and gets wet by rain, recheck it before pouring concrete to reinforce the formwork and support.

7. Formwork and components: The stacking area should be hardened and firmly inserted. Before pouring concrete in rainy days, carefully check the formwork and support to prevent the formwork support from loosening.

8. When the big formwork falls to the ground, the ground should be solid and supported firmly.

9. The formwork and square timber used in the main structure shall be dismantled in time and transported to the designated site to prevent the formwork and square timber from being exposed to the sun and rain.

Fourth, the concrete construction

1. Mixing proportion adjustment

Slump loss should be fully considered when adjusting the mixture ratio to reduce concrete slump loss and avoid hydration heat concentration. Cement with low hydration heat can be used as raw material, and the setting time of concrete can be delayed by adjusting the content of compound admixture to meet the construction requirements.

2. Mixing and transportation of concrete

Effective measures should be taken to control the mixing temperature of concrete in hot season. By mixing with low-temperature water and washing aggregate with cold water, measures are taken to control the temperature of cement entering the machine and reduce the mixing temperature of concrete.

(1) In summer, cold water is poured on the body of the concrete transport vehicle to prevent the heat of the steel tank from being transferred to the concrete, thus causing the temperature of the concrete to rise. Before each concrete construction, each concrete transporter to be constructed is required to sprinkle water to cool down, so as to avoid evaporation of water in concrete due to high humidity and reduce the construction quality of concrete.

(2) In the process of concrete transportation, the road should be kept flat and smooth, and the concrete should be kept uniform during transportation. When transported to the pouring site, it will not be layered or separated, and it will have the required slump and air content.

(3) Pump concrete, wrap the pump pipe with felt, and regularly sprinkle water on the surface of the pump pipe to reduce the temperature rise of the pump pipe caused by sunlight and concrete friction, and avoid concrete slump loss and pipe plugging.

(4) When pouring concrete, attention should be paid to drawing water and wetting the pump pipe with mortar. The transportation capacity of concrete transportation equipment should meet the needs of concrete setting speed and pouring speed to ensure the continuous pouring process.

3. Concrete pouring

(1) Strengthening temperature observation in construction can avoid temperature cracks.

(2) Take appropriate temperature control measures: reduce the pouring temperature, pay attention to the sun protection of aggregate during concrete construction, add ice cubes or ice water to mix concrete, and cover the container during transportation to prevent sun exposure; Reduce the temperature rise of hydration heat, choose reasonable raw materials, adopt good mixture ratio and reduce the dosage of cement; In order to prevent surface cracks, measures can be taken to improve the surface temperature of concrete, such as thermal insulation covering the exposed surface of concrete structure, erection of thermal insulation shed and covering with plastic film.

(3) When pouring mass concrete, cooling water pipes (serpentine pipes) can be buried in the structure and cooled with circulating water.

4. Maintenance of concrete

If the concrete poured in summer is not properly maintained, it will reduce the strength of concrete or cause plastic shrinkage cracks on the surface.

(1) curing shall be carried out immediately after the completion of operation or initial setting of concrete, and continuous curing shall be carried out by spraying water. For the first 7 days after concrete pouring, the concrete shall be kept fully moist.

(2) After the specified curing is completed, it is best to provide a wet cover for its surface when uncovering the film.

(3) Tap water or qualified water source must be used for concrete curing, and sewage or acidic water shall not be used. Sprinkling times should be based on the wet state of concrete surface.

(4) If artificial watering and spraying are used for curing, the concrete surface can be covered (wrapped) tightly with absorbent materials such as geotextile, sacks and cotton felt, and the interval between watering and spraying is short. Keep the inside and outside of the hood moist from beginning to end to prevent dry-wet cycle. Generally speaking, the curing water temperature should not be lower than 15℃, and the difference between curing water temperature and concrete surface temperature should not be higher than 15℃, so as to prevent cracks on concrete surface.

(5) When the concrete surface is wrapped with plastic film for moisture curing, the plastic film should have certain crack resistance, tensile strength and flexibility. After the concrete is demoulded, water should be sprayed on the concrete surface first, and it should be wrapped immediately. Plastic film should be close to the concrete surface to avoid leakage and air tightness.

During the curing period, water droplets will appear on the concrete surface from beginning to end. In order to keep the concrete surface moist, water can be sprayed into the plastic film regularly, and the integrity of the film should be checked frequently. If the plastic film is found to be broken, it should be repaired in time.

(6) According to different meteorological temperature conditions and different structural characteristics, the curing period of high performance concrete should generally be controlled within 14-28 days. During this curing period, heat preservation and curing measures should be taken to ensure that the curing humidity of concrete meets the requirements and the hydration of concrete can proceed smoothly.