(1) The bearing capacity of piles will see breakthrough development. Currently, single piles with a bearing capacity of 1,500 tons are rare, but in the future, as long as the superstructure requires it, piles with loads exceeding 2,000 tons will not be a problem. From an economic perspective, the structural form of one column supported by one pile can be widely adopted. Achieving this goal will require progress in pile materials and pile-driving equipment. The strength and diameter (>1 m) of PHC piles (high-strength prestressed concrete pipe piles) will be increased. In terms of pile-driving equipment, the combination of hydraulic hammers and mud rotary drilling will make it no problem to penetrate sand and gravel layers at depths of 20–30 m. A new type of composite pile is bound to emerge; this pile type will be a combination of H-section steel piles, which have strong penetration capability, and PHC piles.

     (2) The shape of piles will inevitably break through the concept of straight shafts and linear forms, evolving into support structures of different configurations. For example, open caisson structures are used for tube-in-tube and tube-cage structures in high-rise buildings, and underground diaphragm walls have already become part of basement exterior walls. Sheet-like, zigzag, and grid-like underground support structures—different from existing pile foundations but possessing the functions and concepts of piles—will inevitably partially or locally replace monotonous pile foundations. The construction machinery for such underground support structures will not be traditional pile drivers, but rather excavators modeled on underground diaphragm wall construction machinery. If a breakthrough is made in compressed-air wall protection, the bottom can be enlarged to form a belled pier-type enlarged head, further improving its bearing capacity, reducing settlement, and lowering costs.

     (3) Currently, pile materials are mainly reinforced concrete, followed by steel piles. With the development of polymer materials in the chemical industry, it is not necessarily impossible to manufacture high-strength chemical composite piles comparable to reinforced concrete piles through chemical grouting. At present, cement-soil mixing piles are widely used in composite foundation treatment, and chemical grouting is also a common method. On this basis, the development of mixing piles and mixing walls made of chemical materials and soil for purposes such as seepage prevention and water retention should be just around the corner.