How many days can hydraulic shoring be used before hydraulic bleeds down?

• A. Two days
• B. Eight days
• C. Six days
• D. Four days

Answer: (A)

Hydraulic shoring works by using a sealed hydraulic system to push and hold shields against trench walls. The effectiveness depends on maintaining pressure in that system. Over time, seals and fittings can leak and temperature changes can cause fluid expansion or contraction, so the pressure gradually bleeds down. Because of this potential loss of support, the safest practice is to limit continuous use to a short period—two days—before rechecking the system, re-pressurizing, or restoring the shoring setup. This helps ensure the trench remains protected and reduces the risk of wall movement if the hydraulic pressure drops. If more time is needed, a different approach or additional support should be considered rather than relying on the same hydraulic setup without reinspection.