Major casualties caused by the collapse of coupler scaffolding will be repeated and inevitable. The reasons can be summarized as follows:
First, the quality of coupler steel pipe scaffolding in my country is seriously out of control.
Table 5.1.7 in the specification JGJ130-2001 stipulates that the anti-slip bearing capacity of the butt fastener is 3.2KN, and the anti-slip bearing capacity of the right-angle and rotary fastener is 8KN. Some experts found from on-site inspections that it is difficult for products in actual applications to meet this requirement. After a major accident occurred at a construction site, the couplers were inspected, and the qualified rate was 0%.
Second, the quality of the steel pipe is seriously out of control.
A large number of steel pipes without effective anti-rust treatment have flowed into the market. Since they have not been confirmed by an effective quality inspection system, the products cannot provide quality assurance of safety standard loads, which seriously violates the principle of zero quality defects. In addition, in reality, due to unfair competition, construction units and leasing companies use inferior steel pipes, and some projects even use scrap steel pipes as scaffolding. Objectively, the safety of the coupler steel pipe scaffolding is completely out of control. Some experts inspected the steel pipes after a major accident in a certain project, and the qualified rate was only 50%.
Third, the problem of on-site erection and construction safety management.
The flexible and diverse application characteristics of the coupler steel pipe scaffolding also bring huge uncertainty in the on-site erection and construction process. The various safety hazards caused by the lack of management, lack of training, lack of unified design command, and lack of responsibility due to subcontracting at all levels are simply difficult to enumerate.
Fourth, wrong application.
According to the experience of developed countries, the coupler steel pipe scaffolding can only be used for auxiliary connection and scissor bracing in other scaffolding and support system applications such as gantry, cup-hook scaffolding, and disc-hook scaffolding. It can never be used to build any large scaffolding system, let alone support systems with high load requirements. As far as I know, the coupler steel pipe scaffolding, which accounts for about 10% of our company’s export volume, is not used to build large scaffolding or support systems. In the United States, even the construction and maintenance of common two-story villas use gantry frames, and I have never seen coupler steel pipe scaffolding used to build construction platforms. The reason is simple. If it is used in this way, even if the quality of American standard couplers and steel pipe scaffolding is fully in line with safety requirements. However, since the erection plan is difficult to standardize, the erection process cannot be guaranteed to be safe because of the uncontrollable details of too many manual operations. At the same time, compared with the gantry or cup-hook scaffolding, the labor and steel consumption of such an application are doubled, resulting in a sharp increase in the total cost of the project and losing the application’s significance in terms of economic efficiency.
Fifth, wrong standard orientation.
The “JGJ130-2001 Safety Technical Specification for Fastener-type Steel Pipe Scaffolding in Construction” approved by the Ministry of Construction of the People’s Republic of China on February 9, 2001 and implemented on June 1, 2001 is an industry standard promulgated earlier in my country, which has a profound impact on the design and construction of scaffolding erection and dismantling in my country. Many technical personnel of design and construction units use the methods and specifications provided by this standard as the basis for system erection and construction design. Many published papers use this standard as the basis to discuss how to correctly verify whether the load of the scaffolding application system is reasonable, whether the erection is correct, and even analyze the causes of scaffolding collapse accidents based on this standard. It is worth noting that after many collapse accidents, the re-calculation of load calculations performed according to these standards is still qualified. In other words, the collapse accidents that have occurred should not have occurred in theory. This embarrassing phenomenon itself is caused by the wrong guidance of the standard on the application of modified products. The “5. Design Calculation” and “6. Construction Requirements” in the standard tell us how to calculate and set up large scaffolding application systems. The “6.8. Formwork Support” section in the standard tells us how to use the fastener-type steel pipe scaffolding to set up the support system. These fundamental, misguided ideas come from the fact that we still have a vague understanding of the common sense that has been confirmed by the application experience of developed countries.
Post time: Jul-22-2025