Abstract: Vertical and annular reinforcing steel bar stress and pipe-soil contact pressure during pipe jacking were monitored on the spot. Field data were analyzed. It showed that axis force increased along with pipe jacking at the very start, and it maintained stated basically when jacking to a certain distance. When inner side reinforcing steel bar of tip and bottom pipe were pulled, outer side were pressed. And both sides of pipe were just contrary. Reinforced concrete pipe could be regarded as flexible pipe. Annular reinforcing steel bar bears very little but with great alteration. Pipe-soil contact pressure increased slowly along with pipe jacking, and it also maintained stated basically after some distance. Contact pressure of tip pipe was greatly affected by grouting. The pressure decreased obviously after grouting and it could be adopted as up-earth gravity. Contact pressures of both sides were affected less. Compared with the tip pipe, they were almost the same before grouting and noticeably bigger after grouting.

Key words: pipe jacking, pipe stress, pipe-soil contact pressure, site monitoring