In the process of reinforcing and renovating existing structures, pile foundations play a pivotal role in foundation enhancement, renovation, or underpinning of buildings. Alas, conventional equipment and methodologies frequently fall short in fulfilling the construction requirements of pile foundations characterized by large diameters, lengths, and high load-bearing capacities, especially under the constraints of low internal headroom conditions within existing buildings. To address these specific demands, anchor jacked pile technology and cement-soil composite pile technology is integrated, subsequently leading to the development of low-clearance jet grouting jacked composite pile technology and a comprehensive set of jet grouting jacked integrated equipment. The feasibility of this state-of-the-art approach has been substantiated through extensive full-scale field tests, which have also allowed for a comparative evaluation of the construction techniques, individual pile load-bearing capacities, and internal pile forces for jet grouting jacked composite piles, rotary jet grouting piles and jacked piles. The experimental results emphasize that jet grouting jacked composite pile technology exhibits a considerably enhanced bearing capacity in comparison to traditional jacked and jet grouting piles, thus indicating its potential in effectively tackling the challenges associated with reinforcing and renovating pre-existing structures.