The management and control of dangerous and large projects is the key point in the project construction, one of the keys of the project supervision control, and also an important work of the supervision control in advance and in the process.
1. Current Situation of Construction Supervision of Dangerous and Large Projects and Suggestions for Improvement
At this stage, all participating units are uneven in project management and technical level, passive in the evaluation, scheme preparation, review, supervision review, implementation and other work quality of major and dangerous projects, and have blind, random, “three violations” and other bad behaviors, which are easy to cause production safety hazards or accidents.
Once the accident occurs, the supervision organization is liable to be held accountable for its lack of supervision responsibilities, and even some supervisors are held criminally responsible. Therefore, the management and control of dangerous and large projects is particularly important to the work of the supervision organization, and it is also an important embodiment of the high-quality service of supervision.
In order to strengthen the safety management of divisional and subdivisional works with high risks in housing construction and municipal infrastructure projects, and effectively prevent production safety accidents, the Ministry of Housing and Urban Rural Development has successively issued the Provisions on Safety Management of Divisional and Subdivisional Works with High Risks (Ministry of Housing and Urban Rural Development [2018] №37 Order), the Notice on Issues Related to the Provisions on Safety Management of Divisional and Subdivisional Works with High Risks (Ministry of Housing and Urban Rural Development [2018] №31 Document), etc, In combination with documents and relevant requirements, this paper mainly expounds how to realize high-quality supervision of major and dangerous projects from the aspects of identification, summary, scheme preparation, expert argumentation, supervision approval and implementation inspection and acceptance of major and dangerous projects. Scope of divisional and subdivisional works with high risk
1、 Foundation pit works
(1) Earth excavation, support and dewatering works of foundation pit (trench) with excavation depth of more than 3m (including 3m).
(2) Although the excavation depth is not more than 3m, the geological conditions, surrounding environment and underground pipelines are complex, or the earthwork excavation, support and dewatering works of foundation pits (trenches) that affect the safety of adjacent buildings and structures.
2、 Formwork and support system
(1) Various tool type formwork works: including sliding formwork, climbing formwork, flying formwork, tunnel formwork, etc.
(2) Concrete formwork support works: concrete formwork support works with an erection height of 5m or more, or an erection span of 10m or more, or with a total construction load (design value of basic combination of load effects, hereinafter referred to as design value) of 10kN/m2 or more, or with a concentrated line load (design value) of 15kN/m or more, or with a height greater than the horizontal projection width of the support and relatively independent and unconnected members.
(3) Bearing support system: used for full hall support system such as steel structure installation.
3、 Hoisting and hoisting, installation and removal of hoisting machinery
(1) Non conventional lifting equipment and methods are used, and the single piece lifting weight is 10kN or more.
(2) Installation works with hoisting machinery.
(3) Installation and dismantling of hoisting machinery.
4、 Scaffolding works
(1) Floor type steel pipe scaffold works (including lighting shaft and elevator shaft scaffold) with a height of 24m and above.
(2) Attached lifting scaffold works.
(3) Cantilever scaffold works.
(4) Hanging basket for work at heights.
(5) Unloading platform and operation platform works.
(6) Special scaffold works.
5、 Demolition works
Demolition works that may affect the safety of pedestrians, traffic, power facilities, communication facilities or other buildings and structures.
6、 Concealed excavation works
Tunnels and caverns constructed by mining method, shield tunneling method and pipe jacking method.
7、 Others
(1) Building curtain wall installation works.
(2) Installation of steel structure, grid structure and cable membrane structure.
(3) Manual hole digging pile works.
(4) Underwater operation works.
(5) Installation of prefabricated concrete components for prefabricated buildings.
(6) The adoption of new technology, new process, new materials and new equipment may affect the construction safety of the project, and there is no national, industrial and local technical standard for divisional and sub divisional works.
2. Scope of divisional and subdivisional works with greater risk exceeding a certain scale
1、 Deep foundation pit works
Earth excavation, support and dewatering works of foundation pit (trench) with excavation depth of more than 5m (including 5m).
2、 Formwork and support system
(1) Various tool type formwork works: including sliding formwork, climbing formwork, flying formwork, tunnel formwork, etc.
(2) Concrete formwork support works: the erection height is 8m and above, or the erection span is 18m and above, or the total construction load (design value) is 15kN/m2 and above, or the concentrated line load (design value) is 20kN/m and above.
(3) Bearing support system: it is used for steel structure installation and other full hall support systems, bearing single point concentrated load of 7kN and above.
3、 Hoisting and hoisting, installation and removal of hoisting machinery
(1) Non conventional lifting equipment and methods are used, and the single piece lifting weight is 100kN or above.
(2) Installation and dismantling of hoisting machinery with a hoisting capacity of 300kN or above, or with a total erection height of 200m or above, or with a foundation elevation of 200m or above.
4、 Scaffolding works
(1) Floor type steel pipe scaffold works with a height of 50m and above.
(2) Attached lifting scaffold works or attached lifting operation platform works with lifting height of 150m and above.
(3) Cantilever scaffold works with the erection height of 20m and above for segmented scaffold.
5、 Demolition works
(1) Wharf, bridge, overhead, chimney, water tower or demolition works of special buildings and structures that are easy to cause toxic and harmful gas (liquid) or dust diffusion, flammable and explosive accidents during demolition.
(2) Demolition works within the scope of influence of cultural relics protection buildings, excellent historical buildings or historical and cultural areas.
6、 Concealed excavation works
Tunnels and caverns constructed by mining method, shield tunneling method and pipe jacking method.
7、 Others
(1) Installation of building curtain wall with construction height of 50m and above.
(2) Steel structure installation works with a span of 36m and above, or space truss and cable membrane structure installation works with a span of 60m and above.
(3) Manual hole digging pile works with excavation depth of 16m and above.
(4) Underwater operation works.
(5) The overall lifting, translation, rotation and other construction processes of large structures with a weight of 1000kN and above.
(6) The adoption of new technology, new process, new materials and new equipment may affect the construction safety of the project, and there is no national, industrial and local technical standard for divisional and sub divisional works.
3. How to Realize High Quality Supervision of Dangerous and Large Projects
1、 Prepare the list of dangerous and major projects and special construction plan
The specific work is as follows:
(1) The Director shall review the division of unit, divisional and subdivisional works declared by the construction unit in combination with relevant engineering quality inspection and evaluation standards, construction design documents and other relevant provisions, so as to lay a solid foundation for the construction unit to carry out the evaluation of major and dangerous projects and prepare the list of major and dangerous projects.
(2) The supervision organization shall assign supervisors with rich experience in construction supervision to participate in the safety risk identification and assessment organized by the construction company.
(3) The supervision organization shall review the list of major and dangerous works declared by the construction company according to the division and risk assessment report of unit, divisional and sub divisional works. The special construction scheme to be prepared shall be specified in the list of major dangerous projects, which shall be demonstrated and reviewed by experts. The list of major dangerous projects shall be approved by the director and reported to the construction unit and the supervision company.
(4) The technical director of the construction unit shall reasonably determine the preparation, review, (demonstration), approval, implementation and other work plans of each special construction scheme according to the approved overall schedule, list of dangerous and major projects, etc. The special construction plan shall be approved by the Director and reported to the Employer and the Supervisor.
2、 Prepare special construction scheme for dangerous and large projects
In the construction preparation stage, the construction unit shall standardize the work flow of preparation, review and application of special construction scheme for major and dangerous projects.
(1) Verify the members of the construction company’s scheme preparation team: to prepare a more complete scheme, the construction company should establish a technical public relations team to formulate a scheme preparation plan. The supervision organization should participate in collecting relevant data, reviewing design documents, and conducting in-depth field surveys. (2) Standardize the construction company’s plan review process: check whether the construction company has established an internal special construction plan review team to form a standardized internal review process; Whether the internal level audit system or comprehensive joint audit system has been implemented.
(3) Verify the framework system of the construction company’s scheme preparation: the corresponding supervision engineer shall participate in the preparation of the scheme framework system. According to the relevant requirements of the construction contract, design documents, general construction team, risk assessment, emergency plan and other factors, such as the surrounding environment of the construction site, geological and hydrological conditions, climatic conditions, underground pipelines and other factors, it is proposed to determine the framework system of the special construction scheme preparation, and collect data related to the dangerous project.
3、 Review the special construction scheme of dangerous large projects
The chief director is the main responsible person for the review of the special construction scheme of dangerous and large projects. The chief director shall organize the relevant special supervisors and supervisors of the supervision organization to participate in the review. The construction unit shall organize experts to demonstrate and review the special construction scheme for large and dangerous projects exceeding a certain scale.
1. Director organizes review
Before reviewing the special construction scheme of dangerous and large projects, the supervision organization shall establish a scheme review team, which is generally composed of the director, special supervisors (quality, safety, test, etc.) and supervisors.
(1) The supervision organization shall collect relevant review basis and check whether the latest relevant basis is adopted. The Director shall first review whether the framework system of the special construction scheme is complete and whether the main contents of the scheme meet the mandatory standards (national standards, industrial standards); Then the special supervisor and supervisor shall review the compliance of the detailed contents of the scheme against the technical specifications, general construction team, design drawings, etc.
(2) Review the project overview, and determine relevant important parameters against the construction design drawings, including determining whether the description of the surrounding construction environment, pipeline disclosure content, cross influence scope, hydrogeology, climate and meteorology and other conditions is complete, generally including the basic situation of the project, construction layout, construction requirements, technical conditions, etc.
(3) Review the construction plan to determine whether the construction progress plan, personnel, equipment and tools, materials and semi-finished products mobilization plan, cost use plan, etc. of the dangerous project meet the construction requirements, including the description of the type and quantity of personnel, mechanical model combination and quantity, material name and quantity, etc.
(4) Review the construction organization and process technology, including the leadership, functions of the construction unit, the organization of the operation level and the division of responsibilities of relevant construction personnel, technical parameters, process flow, construction methods, inspection and acceptance, control measures, etc. If the requirements are not met, the written extracts shall be submitted to the scheme preparer for modification.
(5) Review quality, safety, environment and other assurance measures, including organizational measures, technical measures, risk source notification, safety precautions, emergency plans or emergency disposal, monitoring and monitoring, and correct and modify the missing items or incomplete parts.
(6) Relevant calculations or checking statements in the standardized scheme, review the references, calculation formulas, value references, calculation process, allowable value determination and other important contents in the calculation statement, and check whether the calculation bookmark and seal are complete. If the computer model software calculation system is adopted, the name of the software shall be specified, the three-dimensional check calculation diagram or check calculation results of the check calculation model shall be attached, and the degree of force influence shall be reflected by the color mark of the model.
(7) Review whether the construction chart design in the appendix of the scheme is complete. The construction unit shall prepare the engineering design drawings, relevant plans, and engineering tables in a standardized manner, and cover the whole construction process of major and dangerous projects.
(8) Actively encourage the construction unit to adopt innovative scientific and technological means to apply them to the preparation system of special schemes for dangerous large projects, such as BIM technology application, monitoring and monitoring system, media video control, etc.
2. Expert argumentation and review
For large and dangerous projects exceeding a certain scale, the construction unit shall organize an expert demonstration meeting to demonstrate the special construction scheme. In case of general construction contracting, the general construction contractor shall organize an expert demonstration meeting. Before expert argumentation, the special construction scheme shall be reviewed by the construction unit and the chief supervision engineer.
After the expert argumentation meeting, an argumentation report shall be formed, and consensus on the approval, modification and disapproval of the special construction scheme shall be put forward. The expert is responsible for the demonstration report and signs for confirmation.
If the special construction scheme needs to be modified and approved after demonstration, the construction unit shall modify and improve it according to the demonstration report. The special construction scheme shall be reviewed and signed by the technical director of the construction unit, affixed with the official seal of the unit, reviewed and signed by the chief supervision engineer, and affixed with the professional seal before implementation.
If the special construction scheme fails to pass the demonstration, the construction unit shall reorganize the expert demonstration according to the requirements of this provision after modification.
[Participants]
The participants in the expert demonstration meeting of special construction scheme for dangerous and large projects exceeding a certain scale shall include:
(1) Experts (experts shall be selected from the expert pool established by the competent housing and urban and rural construction department of the local people’s government, and the number of experts shall not be less than 5, who meet the professional requirements, and those who have an interest in the project shall not participate in the expert demonstration meeting as experts);
(2) Project leader of the construction unit;
(3) Project technical directors and relevant personnel of relevant survey and design units;
(4) Technical directors of the General Contractor and subcontractors or authorized professional technicians, project directors, project technical directors, special construction scheme preparers, full-time project safety production management personnel and relevant personnel;
(5) The project chief supervision engineer and professional supervision engineer of the supervision unit.
[Demonstration content]
For the special construction scheme of large and dangerous projects exceeding a certain scale, the main contents of expert demonstration shall include:
(1) Whether the contents of the special construction plan are complete and feasible;
(2) Whether the calculation sheet, checking basis and construction drawings of special construction scheme conform to relevant standards and specifications;
(3) Whether the special construction scheme meets the actual situation on site and can ensure construction safety.
4. Implement supervision of dangerous and large projects
(1) The director shall check the performance of specific personnel on duty against the list of quality and safety organizations, environmental protection, emergency plans and other leading groups in the plan, and assess if necessary. In case of incompetence or nonperformance of duties, the construction unit shall be required to replace and the project leader shall be notified in writing.
(2) The Chief Engineer shall organize to check the preparation of the construction site, construction elements, operating environment, etc., whether the name, hazard source, construction time and relevant responsible person of the dangerous project are publicized in a prominent place, and set up safety warning signs in the dangerous area.
(3) The Chief Engineer shall organize relevant supervisors to participate in the disclosure of the special construction scheme of the construction company, check whether the safety technical disclosure of the construction site management personnel to the operating personnel is in place, and review the training and education of the operating personnel, the wearing of labor supplies, and the employment of special workers with certificates.
(4) The director shall organize the inspection of safety production conditions before the commencement of divisional and sub divisional works, and those meeting the conditions shall be approved by the director; If the conditions are not met, the construction unit shall be urged to continue to rectify and improve.
(5) The supervision organization shall perform relevant supervision systems in strict accordance with the special construction scheme, such as the first piece project approval system, the process inspection and acceptance system, the temporary facilities inspection and acceptance system, and the material mobilization acceptance system, and shall form inspection and acceptance records, image data, strengthen multiple control, and leave no hidden dangers.
(6) In the implementation stage of the special construction scheme, the supervision organization shall comprehensively master the implementation of the scheme through multiple supervision means such as on-site supervision, patrol, inspection and acceptance, detection and monitoring, consulting experts, and talking with on-site personnel. In particular, verify and control the key parts of the project, concealed works, hazardous operations, etc.
(7) If the supervision organization finds that the construction unit fails to implement the special construction scheme, it shall issue a supervision instruction sheet and require the construction unit to rectify. If any potential safety hazard is found, the construction unit shall be required to rectify; If the situation is serious, the construction unit shall be required to stop the construction and report to the construction unit in time. If the construction unit refuses to rectify or stop the construction, the supervision organization shall report to the relevant competent department in time.
(8) Carry out handover and acceptance of divisional and subdivisional works, and urge the management personnel of the construction unit to follow up the removal of dangerous parts (supports, equipment, temporary power, etc.), removal of equipment from the site, restoration of safety facilities, and protection of finished products, without leaving any hidden dangers.
