Demolition of old buildings will result in a waste of resources. The buildings can be re-used through reinforcement, strengthening, and repair, but a little carelessness will lead to a big mistake!
The following reminds you that you must look at the following misunderstandings during structural strengthening reinforcement:
There are hidden safety hazards in buildings, but due to wrong reinforcement design, disordered reinforcement construction procedures, poor reinforcement materials, and unqualified reinforcement procedures, the expected results cannot be achieved after reinforcement, and potential safety hazards still exist, even causing damage during the reinforcement process. After reinforcement, new safety hazards arise!
Adopting integrated bidding for reinforcement and reconstruction design and construction, winning the bid at a low price. It is always believed that reinforcement design and construction can be done with reinforcement qualifications, and there is no need to assess the strength. In the end, it is discovered that the hidden dangers after reinforcement and reconstruction have not been eliminated, but new leaks, cracks, sinks, and inclination have occurred. The situation was so serious that it collapsed and eventually had to be demolished and rebuilt.
It is believed that there is no need for a design and construction team with rich experience. It adopts the general contracting of civil engineering qualifications by individuals, and finally subcontracts and subcontracts. There are shortcomings afterwards, the reinforcement effect cannot be achieved, and there are hidden dangers.
On-site construction personnel only follow the drawings and ignore the actual problems on the site. Although the construction is completed in accordance with relevant specifications and procedures, the newly discovered diseases of the original structure on the site are not treated, resulting in defects after the reinforcement and reconstruction.
The unit price of reinforced and reconstructed steel bars, concrete, and steel structures is equated with the fixed price of ordinary new civil works and steel structures. Reinforcement and reconstruction are affected by the reinforced and reconstructed building, the construction site is limited, the construction technology is limited, the construction process is limited, the construction nodes are increased, the construction efficiency is greatly reduced, and the construction labor cost and the cost of measures are greatly increased. Therefore, the unit price is much higher than the price of new construction.
Because the reinforcement and renovation design did not do the overall experience calculation, the reinforced part of the building was too strong, and the unreinforced part was weak. The building as a whole could not work in coordination and did not meet the requirements of seismic bearing capacity. Therefore, it is recommended to do the overall calculation design for the reinforced and reconstructed buildings.
Regardless of the rigidity requirements, new damage will occur due to insufficient rigidity after reinforcement and transformation. Especially for some structural transformations, such as insufficient beam height when joist pulls out the column, continuous beam slab has become simply supported beam slab when partial beam slab is removed, and it is very dangerous to remove it without considering structural reinforcement.
There is a lack of scientific research and calculations, and sticky steel and carbon fiber are regarded as a cure for all diseases. As long as it is reinforced, stick steel, carbon fiber, or even multiple layers regardless of the situation. I just want to compensate for the strength. I don’t understand what is the super-reinforced beam-slab structure and its failure mechanism, nor do I understand that the shear force transmission of the adhesive interface is related to the bonding strength of the beam-slab itself. Although it is reinforced, hidden dangers still exist.
For the design of the brick-concrete structure to be transformed into an inner frame, the method of adding foundations and beams, slabs and columns first, and then removing the inner walls and each layer board was not taken. Instead, the internal walls and slabs are first demolished in the construction, and the external walls are unstable. Even if temporary supports are added, their support will affect the construction space and deform, which will cause unsafe factors in the reconstruction construction.
When the outer steel is used for reinforcement, the adhesive glue is used to paste the outer steel and then welded, causing the welding to burn out the adhesive. Or do not pay attention to the bonding glue, use unqualified glue types, replace the bonding glue with cement mortar, etc.
It is believed that the role of adhesive glue without anchoring measures, or despite the addition of anchoring measures, the hidden dangers caused by factors such as low shear resistance and low bonding ability caused by the low strength of the reinforced concrete are still present. As a result, the bonding fails after the pasting and reinforcement, and the separation is chipped off, resulting in new hidden dangers or sudden failure of the structure during use.
Emphasizes the need to implement the terms that should not be violated in the new construction code, so that it cannot be reinforced or allowed to freely, without scientific treatment measures, making the reinforced nodes and structures unreliable, etc., to two extremes.
Due to the lack of attention to the reinforcement and transformation projects, random subcontracting and subcontracting, the reinforcement and transformation team has no structural professionals, with a little knowledge of the structure, not familiar with the reinforcement and transformation, and does not understand the design intent of the reinforcement and transformation. It will only do the construction of various processes, and the lack of strict control of the process, or the chaos of the process, or no unloading measures, no monitoring behavior, etc. cause safety hazards during or after construction.
Language: English
