To extend the work period and shoulder half of the expenditures of the additional work in the event of unforeseen difficult ground condition in piling work performed according to the contractor s design 又或在打桩工程按承建商的设计进行而遇到不可预知复杂岩土的情况时，房委会会予以延长施工期，并承担相关额外工程支出的半数。
