Issues related to design changes in civil engineering construction
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During the construction of the civil engineering foundation, without the approval of the design institute, the construction party altered the design, changing the structure of 8 rebar bars of 6 different sizes to one consisting of 4 rebar bars of 10 different sizes, which were then tied together. Doing this certainly doesn’t meet the standards, but the foundation has already been poured. Has anyone encountered such an incident before? Can we just make do like this, or does it have to be dug up and rebuilt? I seek help from experts to resolve this issue. . . .
Why isn’t construction carried out in accordance with the design requirements? In such cases, it’s usually possible to have the designer redo the calculations to determine whether the structure can bear the weight. But most people are afraid of taking responsibility and won’t rashly issue a certificate! I work on chimney construction projects. Sometimes, when we encounter mountainous areas, there are too many stones during foundation excavation, making it difficult to reach the designed depth. We want to reduce the excavation depth, but no one is willing to issue a certificate for that, so in the end we have to use pneumatic hammers to break the stones!
It’s impossible to dig it out; we can recalculate. The static pressure tests conducted during inspection are carried out at a higher frequency for this type of cast-in-place pile. If the quantity is small, it’s easy to handle – just add a few more. But if there are too many… . . . . .
The structure of 8 bars, each with a diameter of 6, has been changed to 4 bars, each with a diameter of 10. In civil engineering construction, steel bars can be replaced. There are two principles for such replacements: one is replacement based on equal area, that is, replacement with bars of equal cross-sectional area; the other is replacement based on equal strength. However, in either case, approval from the designer is required
Here, the cannon mechanism must be opened for rework, and all costs must be borne entirely by the contractor! This practice of ignoring design principles and making arbitrary changes to them must be met with zero tolerance. If you compromise once, there will surely be a second time; and when problems arise, those who adopt an indifferent attitude cannot escape responsibility! Why harm oneself?
The specifications require that any replacement of rebar must be approved by design. Equal-area substitution and equal-strength substitution only meet the strength requirements; after substitution, the structural requirements and crack requirements must also be satisfied.
It depends on whether you are the contractor or the client. This is a case of acting first and reporting later, something that happens frequently during construction. Once this occurs, the contractor can choose to hide it from the owner, as long as it remains undiscovered. Moreover, out of a sense of responsibility for safety, it is also necessary to ensure that any changes made to the design still meet the requirements of the original design.
It’s necessary to design a reconfirmation; wish the original poster good luck