foundation pit project safety manual directory
1, construction plan
2, foundation pit support
3, drainage
4, foundation pit excavation
5, pit edge load
6, security protection
7, foundation pit monitoring
8, support demolition
9, operating environment
10, emergency plan
, construction plan
★ Special construction plans should be prepared for foundation pit projects
★ Special construction plans should be reviewed and approved in accordance with regulations
Setting requirements:
1. Special construction plans should be prepared separately for foundation pit earth excavation, support and precipitation projects with excavation depth exceeding 3m (including 3m) or not exceeding 3m but with complex geological conditions and surrounding environment. (Attachment I of Building Quality [2009] No. 87)
2. Before the construction of the foundation pit project, the "Regulations on Safety Management of Sub-Projects with Highly Risk (Construction Quality (2009) No. 87) No. 13) shall be conducted, and the technical department of the construction enterprise shall organize the professional and technical personnel of the construction technology, safety, quality and other departments of the unit for review. If the review is approved, the technical person in charge of the construction enterprise shall be signed by the technical person in charge, stamped with the official seal of the unit's legal person and then submitted to the supervision enterprise. The project supervisor engineer shall review and sign and stamp the professional qualification registration seal. (Construction Quality [2009] Article 87)
Foundation Pit Maintenance★The special construction plan for foundation pit projects exceeding a certain scale should be organized to organize experts to demonstrate the setting requirements of
:
1. Earth excavation, support and precipitation projects of foundation pits (troughs) with excavation depth exceeding 5m (including 5m). (Attachment II of Building Quality [2009] [2009])
2. Although the excavation depth does not exceed 5m, the geological conditions, surrounding environment and underground pipelines are complex, or the earth excavation, support and precipitation projects of foundation pits (troughs) that affect the safety of adjacent buildings (structures). Earth excavation, support and precipitation projects. (Attachment II of Construction Quality [2009] No. 87)
★ If the surrounding environment or construction conditions of the foundation pit change, the special construction plan should be reviewed and approved again
Setting requirements: foundation pit support structure is greatly affected by the surrounding environment and the changes in excavation depth, and if the original construction plan needs to be changed, the special construction plan should be reviewed and approved again.
Foundation pit protection2. Foundation pit support★ For narrow foundation troughs manually excavated, support measures should be taken for narrow foundation troughs with large excavation depth or slope collapse risk
Steel support supportSetting requirements:
1. Excavation depth or slope collapse risk should be selected according to the applicable conditions of Table 3.3.2 in (JGJ120-2012).
2. During the excavation of foundation grooves, observe the changes in support at any time. If there is a significant overturn or bulge, immediately add symmetric support to the overturn or bulge areas.
★ The slope rate of natural slope should comply with the special construction plan and specification requirements
setting requirements:
1. Strictly follow the design and construction plan content, and slop different soil quality according to different slope rates.
2. The following slopes should not be used by the slope rate method (GB50330-2002 Article 12.1.2)
① Slope excavation adversely affects the proposed or adjacent buildings (structures);
② Slopes with groundwater development;
③ Slopes with poor stability
3. Allowed slopes. (GB50330-2002 Table 12.2.1)
★ Foundation pit support structure should meet the design requirements
Underground continuous wall support
Pile-Anchor cable support real picture
Steel support support
Foundation pit support concrete support
Setting requirements:
1. The form of the support structure is strictly constructed according to the design and construction plan content;
2. Support structure type and scope of application.
★ Effective control measures should be taken when the horizontal displacement of the support structure reaches the design alarm value
earth-conversion backpressure
Setting requirements:
1. The monitoring alarm value of the foundation pit project should meet the limit value of the foundation pit project design, the design requirements of the underground main structure, and the control requirements of the monitoring object. The monitoring and alarm value of the foundation pit project is determined by the foundation pit project designer. (GB 50497-2009 Article 8.0.1)
2. The monitoring alarm value of foundation pit project should be controlled by two values: the cumulative change amount and the change rate value of the monitoring project. (GB 50497-2009 Article 8.0.2)
3. The displacement of the inner and outer strata of the foundation pit caused by enclosure wall construction, foundation pit excavation and precipitation shall be controlled according to the following conditions: (GB 50497-2009 Article 8.0.3)
① shall not cause instability of the foundation pit;
② shall not affect the size, shape of the underground structure and the normal construction of underground projects;
③The deformation caused by existing buildings (structures) around shall not exceed the requirements of relevant technical specifications; ④ shall not affect the normal use of surrounding roads, underground pipelines, etc.;
⑤ Meet the technical requirements of special environments.
4. The monitoring alarm value of foundation pit and support structure should be determined based on the monitoring items, characteristics of the support structure and foundation pit level.
★Effective drainage and drainage measures should be taken if groundwater is within the excavation depth range of the foundation pit.
Setting requirements:
1. The precipitation of foundation pit can be carried out using pipe wells, vacuum well points, jet well points, etc., and should be selected according to the applicable conditions in Table 7.3.1. (JGJ120-2012 Article 7.3.1)
2. The designed precipitation water level in the foundation pit should be 0.5m lower than the bottom surface of the foundation pit. When the elevator shaft, water collection well and other parts of the main structure deepen the foundation pit partially, the design precipitation water level should be considered according to its depth or local groundwater control measures should be taken separately for it.
3. When using water cut-off combined with groundwater control method for decompression and decompression precipitation outside the pit, the maximum depth drop value of the water level of the precipitation well should still be specified. Each precipitation well position should form a closed shape at a certain distance along the periphery of the foundation pit. When the groundwater flow rate is small, the precipitation wells should be arranged at equal intervals; when the groundwater flow rate is large, the distance between the precipitation wells should be appropriately reduced in the direction of groundwater recharge. For narrow and long foundation pits with smaller widths, precipitation wells can also be arranged on one side of the foundation pit. (JGJ120-2012 Article 7.3.3)
★ Drainage ditches that meet the specifications should be set up on the ground around the edge of the foundation pit
★ Drainage ditches should be taken for slope excavation, slope surfaces, and slope foot
★ Drainage ditches and water collection wells should be set up around the bottom of the foundation pit, and water accumulation should be removed in time
drainage ditches renderingsSetting requirements:
1. Underground drainage measures should be selected according to the slope hydrological geology and engineering geological conditions. Large-diameter pipe wells, horizontal drainage pipes or drainage cut-off troughs can be selected. When the drain pipe is above the groundwater level, measures should be taken to prevent leakage. (GB50330-2002 Article 3.5.3)
2. Slope project should be equipped with water discharge holes. For rocky slopes, the drainage holes should be given priority in areas with crack development and severe water seepage. Drainage ditches should be installed in front of slope foot, graded platform and support structure. When water seepage on the potential rupture surface is severe, the drainage hole should penetrate deep into the potential rupture surface. (GB50330-2002 Article 3.5.4)
3. Open ditch drainage can be used for groundwater from pit bottom, surface water congestion around foundation pits, and precipitation wells; for groundwater seeping below pit bottom, blind ditch drainage can be used for groundwater; when open ditch cannot be set between the basement floor and the support structure, blind ditch drainage can also be used for groundwater. (JGJ120-2012 Article 7.4.1)
4. The slope of open and blind grooves should not be less than 0.3%. When drainage is used for open ditches, anti-seepage measures should be taken at the bottom of the ditch. When blind ditches are used to discharge groundwater seeped out from the bottom of the pit, its structure, filler and its density should meet the requirements of the main structure. (JGJ120-2012 Article 7.4.3)
5. A water collection well should be set up along the drainage ditch every 30m to 50m; the net cross-sectional dimension of the water collection well should be determined based on the drainage flow. Anti-seepage measures should be taken in water collection wells. (JGJ120-2012 Article 7.4.4)
6. The seepage of the foundation pit slope should be inserted into the water conduit pipe to be discharged. The spacing, diameter and length of the water conduit pipe should be determined based on the seepage amount and the characteristics of the seepage soil layer.(Article 7.4.5 of JGJ120-2012)
7. When using pipes to drain, the diameter of the drainage pipe should be determined based on the drainage volume. The slope of the drain pipe should not be less than 0.5%. The drainage pipe materials can be made of steel pipes and PVC pipes. Drying holes should be installed on the drainage pipes, and the spacing between the dredging holes should not be greater than 10m. (JGJ120-2012 Article 7.4.6)
4. Foundation pit excavation★ The support structure must meet the strength required by the design before excavation can be excavated the lower soil
earth excavationSetting requirements:
1. When the strength of the support structure components reaches the design strength of the excavation stage, excavation can only be achieved; for support structures that use prestressed anchor rod , the lower soil can only be excavated after the pre-addressing force is applied; for the soil nail wall, the lower soil should be excavated after the maintenance time of the soil nail and spray concrete surface layer is greater than 2 days before the lower soil can be excavated. (JGJ120-2012 Article 8.1.1)
2. When the anchor rods, earth nails and support above the excavation surface of the foundation pit do not meet the design requirements, it is strictly forbidden to over-excavate downwards. (JGJ120-2012 Article 8.1.3)
3. During the construction process, it is strictly forbidden for equipment or heavy objects to collide with foundation pit support structures such as support structures, waist beams, anchors, etc., and heavy objects shall not be placed or hung on the support structure. (JGJ180-2009 Article 6.3.2)
★ Strictly follow the requirements of the design and construction plan, excavation in segments and balanced excavation
Setting requirements:
1. Excavation should be layered according to the construction sequence specified in the design of the support structure and the excavation depth. (JGJ120-2012 Article 8.1.1)
2. When excavating to the construction surface of the anchor rod and the soil nail, the height difference between the excavation surface and the anchor rod and the soil nail should not be greater than 500mm. (JGJ120-2012 Article 8.1.1)
3. Excavation of soft soil foundation pits should still comply with the following regulations (JGJ120-2012 Article 8.1.2)
① Excavation should be carried out according to the principles of layering, segmentation, symmetry, balance and timely development;
② When the main structure adopts pile foundation and the foundation pile has been constructed, the excavation thickness of each layer should be limited according to the characteristics of the soft soil under the excavation surface;
③ For support structures that use internal support, it is advisable to pour concrete support or install steel support by troughing; after excavation reaches the support working surface, support construction should be carried out in time;
④ For gravity cement soil walls, excavation should be carried out in sections along the direction of the cement soil wall, and the length of each excavation section should not be greater than 40m.
4. The foundation pit earth should be excavated in different areas and layers in accordance with the excavation plan, controlling the area of the zone, the depth of the layered excavation and excavation speed, and setting up anchors or support in a timely manner to control the impact of time and space on the deformation of the foundation pit from all aspects.
5. The excavation of foundation pit earth should be layered, segmented and balanced according to the design and construction plan requirements, and the principle of anchoring first (support) and then excavating, monitoring while excavating, and protection while excavating. Extremely deep digging is strictly prohibited. (JGJ180-2009 Article 6.1.3)
★ During the excavation of the foundation pit, measures should be taken to prevent collision of support structures, engineering piles or disturbing the original soil of the base.
Professional personnel stand by and command to ensure that the excavation does not collide with the support structureSetting requirements:
1. The construction process should be combined with the on-site construction environment and select appropriate excavation machinery for earth excavation.
2. When excavating around the construction piles, it is advisable to install guardrails around the construction piles or hang warning signs in appropriate places.
3. Pay attention to the visibility of the excavation surface. If necessary, lighting fixtures must be installed for filling light. Reflective signs should be posted near the work area for night construction.
4. During the excavation process, professionals should stand by the side to ensure that the excavation process does not collide with the support structure. Surveyors need to strengthen monitoring of excavation surface elevation to prevent overexcavation.
5. During mechanical excavation, 300-500mm thick soil should be left in the foundation pit and the walls of the pit and then manually excavate and repair; if there is excessive excavation, it should be kept in its original state and should not be filled in falsely. It should be processed after the experience tank.(DBJ/T15-20-97 Article 14.1.5)
★ Machinery operates on soft soil sites, and hardening measures such as laying slag, sand and gravel should be taken
Soft soil site. Effective measures should be taken first to prevent the machinery from sinkingSetting requirements: Dig soil on soft soil sites or silt. When the machinery cannot walk and operate normally, the excavation machinery should be hardened by laying slag, sand and gravel. (JGJ 180-2009 Article 6.3.6)
5. Pit edge load★ The loads of soil, materials and other materials shall not exceed the foundation pit support design permit
★ The safety distance between the construction machinery and the edge of the foundation pit must meet the design requirements
Machinery and material placement diagramSetting requirements:
1. On the vertical pit wall, this safety distance should be appropriately increased. It is not advisable to pile discarded soil at the edge of the foundation pit in soft soil areas. 2. The parking position of construction equipment must be stable. The distance between large and medium-sized construction equipment and pit edges should be determined by calculation based on the weight of the equipment, foundation pit support conditions, soil quality conditions, etc.
6. Security protection★ Protective railings must be set around foundation pits with excavation depths of 2m or above, and the protection railing settings must comply with the specifications requirements
Security protection railingSetting requirements: Protective railings must be installed around foundation pits with excavation depths of more than 2m. The protective railings should comply with the following provisions: (JGJ180-2009 Article 6.2.1)
1. The height of the protective railing should not be less than 1.2m;
2. The protective railings should be composed of cross bars and vertical poles; the cross bars should be equipped with 2 to 3 channels, the lower rods should be 0.3m to 0.6m, and the upper rods should be 1.0m to 1.2m; the spacing between vertical poles should not be greater than 2.0m , the distance between the vertical pole and the slope should be greater than 0.5m;
3. The protective railing should be equipped with a tight-gauge safety net and foot panel; the safety net should be closed from top to bottom; the height of the foot panel should not be less than 180mm, and the height of the lower edge of the foot panel should not be greater than 10mm;
4. The material of the protective railing should be strong enough and must be firmly installed, and the upper pole should be able to bear external forces greater than 1000N in any direction.
★ A special stairway for construction personnel to go up and down must be set up in the foundation pit, and the stairway settings must comply with the specifications and requirements
secure channel
secure channel
precipitation well protection diagramsetting requirements:
1. When precipitation is used at well points, protective covers or fences should be set at the wellhead, and warning signs should be obvious. After the precipitation is stopped, the well should be filled in time. (JGJ180-2009 Article 6.3.10)
2. Pay attention to protecting the wellhead to prevent debris from falling into the well. Check drainage pipes and ditches frequently to prevent leakage. Precipitation in winter, and anti-freeze measures should be taken. (JGJ/T111-98 Article 8.2.3)
7. Foundation pit monitoring★ Before excavation of a foundation pit, a monitoring plan should be prepared, and the monitoring project, monitoring alarm value, monitoring method and the layout of monitoring points, monitoring period and other contents should be clarified.
Monitoring plan should be prepared before excavation of foundation pitsSetting requirements:
1. Construction foundation pit project monitoring should comprehensively consider the foundation pit project design plan, geotechnical engineering conditions of the construction site, surrounding environmental conditions, construction plan and other factors, formulate reasonable monitoring plans, and carefully organize and implement monitoring.
2. Before the construction of the foundation pit project, the monitoring unit should prepare a monitoring plan, and the monitoring plan must be approved by the construction party, the designer, the supervisor, etc.
3. The monitoring plan should include project overview, monitoring purpose and basis.
Foundation pit excavation should clarify the monitoring projectsetting requirements:
1. The monitoring project of foundation pit project should match the foundation pit project design and construction plan.
2. First-level foundation pit should be measured: horizontal displacement at the top of the slope, vertical displacement at the top of the slope, deep horizontal displacement, vertical displacement of columns, support internal force, anchor internal force, groundwater level, vertical displacement of the surrounding surface, horizontal and vertical displacement and inclination of surrounding buildings, surface cracks of surrounding buildings, and deformation of surrounding pipelines.(GB50497-2009 Article 4.2.1)
3. When there are subways, tunnels or other buildings and facilities with special requirements for displacement around the foundation pit, the monitoring project should be determined in consultation with the relevant units. (GB50497-2009 Article 4.2.2)
Foundation pit monitoring should clarify the monitoring alarm valuesetting requirements:
1. Foundation pit project monitoring must determine the monitoring alarm value, and the monitoring alarm value should meet the control requirements of foundation pit engineering design, underground structure design and protected objects in the surrounding environment. (GB 50497-2009 Article 8.0.1)
2. When special circumstances occur, a hazard alarm must be issued immediately and emergency measures should be taken for the protection objects in the foundation pit support structure and surrounding environment. (GB 50497-2009 Article 8.0.7)
Foundation pit monitoring should clarify the monitoring method and the layout of monitoring pointsSetting requirements:
1. The layout of the monitoring points of the foundation pit project should reflect the actual status of the monitoring object and its changing trends. The monitoring points should be arranged on the key characteristic points of internal force and deformation, and should meet the monitoring requirements. (GB 50497-2009 Section 5.1.1)
2. The layout of foundation pit project monitoring points should not hinder the normal work of the monitoring objects, and should reduce the adverse impact on construction work. (GB 50497-2009 Article 5.1.2)
3. The selection of foundation pit monitoring should be determined based on factors such as foundation pit category, design requirements, site conditions, local experience and applicability of methods, and the monitoring method should be reasonable and easy to implement. (GB 50497—2009 Article 6.1.1)
Slope top horizontal displacement monitoring
Slope top vertical displacement monitoring
Ground settlement observation point
Deep horizontal displacement monitoring
Water level monitoring
Surface crack monitoring of surrounding buildings
Anchor cable tension monitoring★ The time interval for foundation pit monitoring should be determined based on the construction progress. When the rate of change of the monitoring results is large, the number of observations should be encrypted.
Monitoring frequency of on-site instrument monitoring Foundation pit category Construction process Foundation pit design depth (m) ≤5m5～10m10～15m＞15m First-level excavation depth (m) ≤51 times/1d1 times/2d1 times/2d5～10
1 times/1d1 times/1d1 times/1d1 times/1d＞10
2 times/1d2 times/1d1 times/1d1 times/1d1 times/1d1 times/1d1 times/1d1 times/1d1 times/1d1 times/1d1 times/1d1 times/1d1 times/1d1 times/1d1 times/1d1 times/1d1 times/1d1 times/5d1 times/2d1 times/1d1 times/1d＞281 Times/7d1 times/5d1 times/3d1 times/3d2nd-level excavation depth (m) ≤51 times/2d1 times/2d
5～10
1 times/1d
1 times/1d
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2. The monitoring frequency of the foundation pit project before excavation is determined according to the specific situation;
3. The instrument monitoring frequency of the project that is suitable for measurement and can be measured can be appropriately reduced according to the specific situation;
4. The monitoring frequency within 3 days after the support of the supported support structure begins to be demolished and the demolition is completed.
Setting requirements:
1. The determination of the monitoring frequency of the foundation pit project should meet the requirements that the system can reflect the important changes of the project measured by the monitoring object without missing the change moment. (GB50497-2009 Article 7.0.1)
2. The monitoring frequency of the monitoring project should be determined based on the types of foundation pits, different construction stages of foundation pits and underground projects, as well as changes in surrounding environment, natural conditions and local experience. When the monitoring value is relatively stable, the monitoring frequency can be appropriately reduced. For the project to be tested, in the absence of data abnormalities and accident signs, please refer to Table B.11.7 for the determination of the on-site instrument monitoring frequency after excavation. (GB50497-2009 Article 7.0.3)
3. When one of the following situations occurs, monitoring should be strengthened and the monitoring frequency should be increased. (GB50497-2009) 7.0.4.
1) Monitoring data reaches the alarm value;
2) Monitoring data changes greatly or the rate is accelerated;
3) There is bad geology not found in the survey;
4) Ultra-deep, long-term excavation or failure to timely support construction violates the design working conditions;
5) A large amount of water accumulated in the foundation pit and surrounding areas, long-term continuous rainfall, and leakage of municipal pipelines;
6) The ground load near the foundation pit suddenly increases or exceeds the design limit;
7) The support structure cracks;
8) The surrounding ground suddenly settles or severe cracks;
9) The adjacent buildings suddenly settles, uneven settlement or severe cracks;
10) Pipe surge, leakage or sand flow occurs at the bottom and side walls of the foundation pit;
11) Reorganize the construction after an accident in the foundation pit project;
12) Other abnormal situations affecting the safety of the foundation pit and surrounding environment occur.
★ In foundation pit excavation monitoring projects, phased monitoring reports should be submitted according to design requirements.
Setting requirements:
1. Foundation pit monitoring and analysis personnel should have strong comprehensive analysis capabilities and be able to provide reliable comprehensive analysis reports in a timely manner. (GB50497-2009 Article 9.0.1)
2. The phased report should include the corresponding engineering, meteorological and surrounding environment profiles of the monitoring stage, the monitoring projects and layout diagrams of the measurement points in the monitoring stage, etc. (GB50497-2009 Article 9.0.11)
8. Support removal★ The removal method and order of the foundation pit support structure should comply with the requirements of the special construction plan.
Setting requirements:
1. The construction unit should fully understand the drawings and materials of the demolition project, conduct on-site surveys, and prepare construction organization design or safety special construction plan. (JGJ147-2004 Article 2.0.2)
2. Operators must be equipped with labor protection service supplies. (JGJ147-2004 Article 4.5.3)
3. Demarcate dangerous areas at the demolition construction site, set up cordons and related safety signs, and special personnel should be assigned to supervise. (JGJ147-2004 Article 4.5.4)
4. Before the construction of the project before demolition, a written safety technical briefing must be given to the construction worker. (JGJ147-2004 Article 5.0.5)
5. Foundation pit support demolition mainly adopts manual demolition, mechanical demolition and other unconventional demolition methods. The demolition is carried out according to the construction plan. The order of demolition should be carried out in accordance with the principle of first construction and then demolition, that is, it will be carried out in layers from bottom to top.
★ During mechanical demolition operation, the construction load shall not be greater than the bearing capacity of the supporting structure
Mechanical demolitionSetting requirements:
1. During construction, a dedicated person must be responsible for monitoring the structural status of the demolished building and keeping records. When there is a trend of unstable state, work must be stopped and effective measures must be taken to eliminate hidden dangers. (JGJ147-2004 Article 4.2.2)
2. During demolition and construction, overloading operations or arbitrarily expanding the scope of use is strictly prohibited. The site for use in machinery and equipment must ensure sufficient bearing capacity. (JGJ147-2004 Article 4.2.3)
3. For larger components, cranes must be used to lift them away to a safe place in time. (JGJ147-2004 Article 4.2.4)
★ When manually dismantling, protective facilities should be set up according to regulations.
Manual dismantling of safety protection
Manual dismantling of safety protectionSetting requirements:
1. The scaffolding used for demolition construction must be constructed according to the erection plan. When operating horizontally, the operator should maintain a safe distance. (JGJ147-2004 Article 4.5.1)
2. When performing manual demolition operations, the removed components should have a safe place to place. (Article 4.1.1, JGJ147-2004)
3. When manually demolishing, corresponding measures should be taken to ensure safety before demolition and construction can be carried out. (JGJ147-2004 Article 4.1.7)
★ Unconventional demolition methods such as blasting and cutting should comply with the current relevant national regulations and requirements.
Blasting demolition
Blasting demolition
Setting requirements:
1. Blasting demolition project should be divided into three levels A, B, and C according to the operating conditions of the surrounding environment, demolition objects, building categories, and blasting scale, and according to the current national standard "Blasting Safety Regulations" GB6722, and corresponding safety technical measures should be taken. Blasting and demolition projects should be subject to safety assessment and can only be implemented after review and approval by relevant local departments. (JGJ147-2004 Article 4.3.1)
2. Construction units engaged in blasting and demolition projects must hold the "Explosive Materials Use License" issued by the statutory department of the project location and undertake the corresponding level of blasting and demolition projects. The blasting and demolition designers should have a blasting engineering and technical personnel operating certificate that undertakes the blasting and demolition operation scope and corresponding levels. Operators engaged in blasting and demolition construction should be on duty with a certificate (JGJ147-2004 Article 4.3.2)
3. During blasting and demolition construction, the blasting parts should be covered and blocked, and the covering materials and shading facilities should be firm and reliable. (JGJ147-2004 Article 4.3.9)
4. When using corrosive static crushing operations, grouting personnel must wear protective gloves and protective glasses. After the crushing agent is injected into the hole, the operator should maintain a safe distance and is strictly prohibited from walking in the hole injection area. (JGJ147-2004 Article 4.4.2)
5. Static crusher is strictly prohibited from being mixed with other materials. (Article 4.4.3 of JGJ147-2004) 6. Between two adjacent holes, it is strictly forbidden to carry out construction simultaneously with the injection of crushing agent. (JGJ147-2004 Article 4.4.4)
★ The safety distance between earthwork machinery and construction personnel in the foundation pit should comply with the specifications.
Foundation pit earthwork machinery safety distance
Foundation pit earthwork machinery safety distanceSetting requirements: Construction personnel should work outside the mechanical slewing radius. (JGJ33-2001 Article 5.1.10)
★ Up and down vertical operations should take effective protective measures according to regulations
Up and down vertical operations protection
Up and down vertical operations protectionSetting requirements:
1. When performing up and down three-dimensional cross-operation, the position of the lower layer operation must be outside the possible fall range radius determined by the height of the above layer, otherwise a safety protection layer should be set. (JGJ80-91 Article 5.2.1)
2. Since objects may fall from above or are affected within the range of the crane's rotating rod, a double-layer protective corridor with the top that can prevent penetration must be set up. (JGJ80-91 Article 5.2.5)
★ Special personnel should be installed to monitor the excavation within various pipelines
Pipeline range construction protectionSetting requirements:
1. Before operation, the location and direction of the construction site (wires, underground cables, pipelines, tunnels, etc.) should be clearly recorded, and marked with obvious marks. Working within 1m of its distance is strictly prohibited. (JGJ33-2001 Article 5.1.3)
2. Machinery shall not operate near overhead transmission lines, and shall leave a safe distance in accordance with the provisions of Article 4.1.17 of the "Technical Regulations on the Use of Construction Machinery" JGJ33-2001. (JGJ33-2001 Article 5.1.7)
3. When excavating soil within 2m of power, communications, gas, water supply and other pipelines, safety protection measures should be taken and a dedicated person should be appointed to supervise it.
★ The construction area should have good lighting, and a light source with sufficient illumination should be set up when the light is weak.
Setting requirements:
1. There must be sufficient illuminance on the working surface and maintain the stability of illuminance;
2. The light source position should be properly configured to avoid direct or reflective string light causing glare.
★ Prepare foundation pit project emergency plan as required, and improve the content
★ Emergency materials, materials, tools and tools should be stored at the construction site and a special warehouse should be set up
Setting requirements:
1. Prepare emergency plans as required before construction. Common types of accidents include water rush, sand rush, collapse, electric shock, object strike, gas poisoning, high altitude fall, etc.;
2 , Before construction, the operators should be briefed and informed;
3. The warehouse must be equipped with special fire extinguishing equipment;
4. Various materials in the warehouse must be classified and arranged neatly and marked;
5. Large-scale equipment and materials are not stored in the project department. The corresponding contact information, contact information and emergency routes of other external units should be made, and they can be called in time when a dangerous situation occurs.
