Understanding API ICP653 Reading 7-Worksheet-04 Part1

APPENDIX B
EVALUATION OF TANK BOTTOM SETTLEMENT
B.1.1 Common methods to monitor potential problem:
a. Initial settlement survey, at erection and hydro.
b. Planned frequency, per soil settlement predictions
c. For existing tanks (with no settlement history), monitoring
should be based on visual observations and prior service history.
B.1.2 Excessive settlement requires evaluation/interpretation of survey
data. Tank should be emptied and releveling repair conducted.
B.1.3 Correcting shell and bottom settlement problems include the following
techniques:
a. Localized bottom plate repair.
b. Partial releveling of tank periphery.
c. Major releveling of shell and bottom.
Charlie Chong/ Fion Zhang