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1. Geological survey reports should be used properly; the choice of foundation type should be determined by oneself, rather than adopting the foundation type recommended in the report. In general, structural designers are more knowledgeable about foundation design than geological surveyors. 2. Impact vibration caisson cast-in-place piles should be used with caution: necking is a common phenomenon. 3. Manual dug piles: Construction in sand and gravel layers (especially during hole expansion) carries a high risk of cross-hole interference, making the work dangerous. If the pile is too short (e.g., less than 6m), it cannot be considered a pile but should be regarded as a pier. 4. Foundation treatment: replacement filling, vibration compaction, CFG piles (settlement should be considered, per Clause 9.1.3 of the foundation treatment standards). 5. The basement floor slab is not designed as a raft slab, but rather uses so-called \"waterproof slabs\"; their thickness should be no less than 300 mm. In addition to the buoyant force of groundwater, there is also the reaction force from the foundation, and it is necessary to calculate the reinforcement required. The crack width should not exceed 0.2 mm (Article 4.1.6, Paragraph 2 of the Technical Code for Waterproofing of Underground Structures GB 50108-2001). 6. Settlement joints are not necessary at expansion joints and seismic joints. The author observed a 6-story masonry structure residence equipped with a seismic joint and a settlement joint, both 100 mm wide; as a result, the strip foundations on either side of the seismic joint were highly eccentric foundations, which is highly inappropriate. 7. The cushion layer under the basement floor slab shall be made of C15 concrete (Code for Waterproofing of Underground Structures, Article 4.1.5). 8. Attention should be paid to the minimum reinforcement ratio ρmin for the vertical and horizontal reinforcement in basement walls. 9. The basement walls should have horizontal construction joints. 10. Leaving only post-cast joints in extremely long basements does not solve the problems of temperature and concrete shrinkage during use; measures such as increasing reinforcement, using crack inhibitors, and employing prestressed concrete should be taken. The spacing between rebar in the exterior walls, floor slab, and roof slab of the basement should not exceed 150 mm. 11. Settlement observation points should be arranged, and detailed drawings of these points should be provided; the observation methods must also be specified, rather than simply stating that they follow certain standards. 12. Check for weak underlying strata of the foundation: The simplified formula (stress diffusion angle θ) in Article 5.2.7 of the \"Code for Design of Foundation Engineering GB 50007-2002\" can be used; however, when Es1/Es2 < 3, no value for θ can be obtained, and the base stress formula can also be used for calculation. 13. For the inspection of pile foundations (including pile body quality and single-pile bearing capacity), there should be explanations regarding the inspection methods and the number of inspections to be carried out; it is not sufficient to state that inspections shall be conducted in accordance with certain standards. 14. Should pure basements without superstructures be designed for seismic resistance in seismic areas? There are already clear regulations regarding this issue; for example, Article 6.1.3, Paragraph 3 of the \"Code for Seismic Design of Buildings GB 50010-2002\" stipulates that \"...for those parts of the basement that do not have an upper structure, grade 3 or a lower grade may be adopted depending on the specific circumstances.\" Similarly, Article 4.8.5 of the \"Technical Code for Concrete Structures in High-Rise Buildings JGJ 3-2002\" states that \"...for those parts of the basement that extend beyond the main building structure and lack an upper structure, grade 3 or grade 4 may be used as the seismic resistance grade, depending on the specific conditions.\" For seismic design with a seismic intensity of 9 degrees, the seismic resistance rating of the basement structure should not be lower than grade II. ”However, clause 4.2 of section 5.2.1 of the Beijing Local Standard \"Technical Details for Building Design in Beijing – Structural Engineering\", published by the Beijing Building Design Standardization Office in December 2004, stipulates that: \"Underground structures without an upper structure, such as underground garages, can be designed without considering seismic requirements.\" ”As for this regulation, both the author and many senior structural design professionals in our institute find it incomprehensible. As is well known, during an earthquake, the seismic forces (energy) propagate through the ground in the form of seismic waves, rather than through the air. Damage also occurs beneath the surface of the ground, in forms such as landslides, collapses, liquefaction (sand spraying), subsidence, and surface cracking, which indicates that seismic forces continue to cause damage underground; as a result, foundation structures are also damaged. Most areas in Beijing are designated with an earthquake resistance intensity of 8 degrees; how can underground structures without an upper structure be designed as non-seismic? 15. For the rest, see the author’s “Discussion on the Construction of Reinforced Concrete Structures (V).” Last edited by Lai Lai on 2009-3-15 00:26]