Foundation work borehole leakage testing system - combines air pressure with water testing to detect leakage in deep hole

摘要

The method of testing holes in the ground for water leakage, prior to sinking foundations for buildings etc., uses apparatus for pumping water down the hole. A tube (10) lowered into the hole to deliver water is fitted with a sealing collar (7) at the top, and a rubber plug (6) just above the bottom to form a water chamber below. A water meter (14) pressure recording devices (20, 22) and manometer (12) are used above ground. To improve the accuracy for deep holes, an air line (28) is passed through the water supply tube, air forced in, then slowly reduced, then the system tested for air leakage. A bubble indicator (30) and air pressure measuring device (32) are used. A non return valve is mounted on the bottom of the air tube (28).