Constellation, le dépôt institutionnel de l'Université du Québec à Chicoutimi

Résumé

Rock mass erosion has been a serious safety concern in recent years, especially in the case of dam spillways. Rock block removal by uplift depends on the weight of the block, shearing resistance developed along the sliding faces and hydraulic forces around the block. The effects of several geomechanical and hydraulic parameters on the hydraulic pressures around a block are being studied using a pilot plant scale laboratory spillway model. This study focuses on the effect of joint opening (JO) and block protrusion (BP) on the hydraulic pressures inside the joint and on the top of the block. The blocks are placed in 5 different configurations for testing with three different opening values between the blocks (3, 10 and 20mm) and different block protrusion heights. The test results show that the pressure on the top of the block has a dominating effect in the uplift of the block as the pressure on the bottom of the block remained almost constant with different JO and BP conditions. Test results revealed that block protrusion plays a very important role in the uplift of a block.