Old building renovation projects have become an important part of urban construction. Construction suspended platforms are widely used in exterior wall renovation and energy-saving retrofitting due to their efficiency and convenience. However, the aging structure and complex environment of old buildings present unique safety challenges for suspended platform construction. How to scientifically adapt the suspended platform equipment and systematically mitigate risks is crucial to ensuring the smooth implementation of the project.
I. Special Risks of Suspended Platform Operations in Old Buildings Old buildings generally suffer from reduced structural load-bearing capacity, numerous wall attachments, and narrow working spaces. According to the "Safety Technical Specification for Construction Tool-Type Scaffolding," the front support of the suspension mechanism is strictly prohibited from being supported on parapet walls or eaves edges, but many old building roofs lack reliable support points. At the same time, inconsistent wall material strength and unclear concealed pipelines increase the risk of collisions and snagging during suspended platform operation. Furthermore, renovation projects are often located in residential areas, with strict restrictions on construction noise and schedules, further compressing the safe working space.
II. Key Safety Considerations for Construction Suspended Platforms
1. Precise Fit of the Suspension System
A specific load-bearing capacity test must be conducted on the roof structure to ensure that the structural load-bearing capacity at the support points exceeds the maximum load value of the suspended platform under various working conditions. When using non-standard forms such as wall-mounted suspensions, a specialized plan should be reviewed by experts. During the installation of the suspension mechanism, workers must maintain a distance of at least 2 meters from the edge of the roof; in confined spaces, fall prevention measures must be implemented.
2. Optimal Configuration of Steel Wire Ropes
Hot-dip galvanized steel wire ropes for suspended platforms are becoming the preferred choice for the renovation of old buildings. Data shows that their service life is four times that of ordinary steel wire ropes, and maintenance costs can be reduced by 65%. A single 12mm diameter steel wire rope is 15% lighter, facilitating position adjustment in confined spaces; the zinc-iron alloy layer has a hardness of HV200 or higher, effectively resisting frictional damage from wall protrusions. Introducing intelligent sensing technology to monitor tension changes and wear levels in real time can reduce the construction accident rate by 25% compared to previous models. 3. Enhanced Safety Measures
The height of the guardrails around the suspended platform should be no less than 800mm and 1100mm respectively, and the base plate should be equipped with a baffle no less than 150mm high. Given the unevenness of the walls of older buildings, cushioning devices such as sponge pads and rubber pads should be added to the sides of the platform to prevent collision damage to existing walls and windows. The horizontal distance from buildings is recommended to be no more than 150mm, and wall-mounted wheels or guide devices should be installed.
III. Systemic Risk Mitigation Measures
1. Pre-construction Risk Assessment
A comprehensive assessment of the suspended platform's usage status, maintenance records, site environment, and personnel qualifications must be conducted before construction. A hierarchical risk assessment index system should be established, covering four dimensions: construction environment, personnel, equipment, and management. Risk levels should be determined using the Delphi method and fuzzy mathematical models.
2. Full-Process Safety Management
Personnel Control: Operators must be certified and wear five-point safety belts. Working under the influence of alcohol or entering/exiting the suspended platform through windows or other unauthorized means is strictly prohibited. Load Control: Strictly limit the load to 80% of the rated load; never use as a vertical transport vehicle.
Environmental Response: Immediately cease operations in case of strong winds (level 5 or above), rain, snow, heavy fog, or other severe weather. Lower the suspended platform to the ground and secure the cables and wire ropes. Isolation measures must be implemented within 10 meters of high-voltage power lines.
Inspection and Maintenance: Implement a pre-shift inspection, joint acceptance, and regular maintenance system, focusing on key devices such as safety locks, speed limiters, and brakes. Safety locks must activate within 30cm of the suspended platform's descent.
3. Intelligent Monitoring and Emergency Response: Promote the installation of intelligent limit devices such as overload alarms, anti-tilt devices, and anti-overshoot devices. Develop emergency plans and equip the platform with manual lowering devices to ensure safe descent to the ground in case of power outages or malfunctions. Implement closed management of the suspended platform, with keys kept by designated personnel to prevent unauthorized movement of the suspension mechanism.
