On those ‘optimizations’.
What material should be used to fill the less than one meter backfill space between the basement exterior wall and the foundation pit support? The design is written in plain soil, but compaction machinery cannot enter the site at all – if there are no technical personnel on the project proposing to “replace with low-grade concrete”, then this location will inevitably settle and crack in the later stage.
A small optimization could result in a cost difference of hundreds of thousands and a few months of time savings.
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