【Daily Discussion】Public Utilities – Water Resources and Hydropower – 20210515
Thread Content
What are the causes of the common sliding failure modes in earth-rock dams? Answer: Reasons for damage: ① Inadequate consideration of the impact of waves; ② Unreasonable design of the slope protection structure; ③ Poor quality control during the construction of the slope protection – the dry-laid stones are not compact enough, with large gaps between them, and in some cases the structure even becomes elevated; ④ Incorrect selection of materials for slope protection; ⑤ During operation and management, a sudden drop in water level in the reservoir creates high seepage pressures behind the slope protection, leading to its expansion, cracking, lifting, and sliding, resulting in damage. If repairs are not carried out promptly, the damage worsens over time; ⑥ The effects of freezing in cold regions. We welcome active participation in discussions; the system offers generous rewards for answering questions from VIP members! ! !
1) Curve sliding surface: When the sliding surface passes through the cohesive soil area, its shape is usually a curved surface with a steep top and a gradually flatter bottom; in stability analysis, it is often replaced by an arc. 2) Sliding surfaces on slopes, which often occur in dam slopes made of non-cohesive soils. Such as in thin-core wall dams, inclined wall dams ； When part of the dam slope is submerged, the sliding surface is usually near-linear, with the turning point generally located near the water surface. 3) Composite sliding surfaces: thick core walls, or various soil dams composed of clay and non-clay soils form composite sliding surfaces. When there are weak interlayers in the dam foundation, due to their low shear strength, the sliding surface does not deepen further downward; instead, a composite sliding surface consisting of curved and straight sections is formed along those interlayers.
1) Curve sliding surface: When the sliding surface passes through the cohesive soil area, its shape is usually a curved surface with a steep top and a gradually flatter bottom; in stability analysis, it is often replaced by an arc. 2) Sliding surfaces on slopes, which often occur in dam slopes made of non-cohesive soils. Such as in thin-core wall dams, inclined wall dams ； When part of the dam slope is submerged, the sliding surface is usually near-linear, with the turning point generally located near the water surface. 3) Composite sliding surfaces: thick core walls, or various soil dams composed of clay and non-clay soils form composite sliding surfaces. When there are weak interlayers in the dam foundation, due to their low shear strength, the sliding surface does not deepen further downward; instead, a composite sliding surface consisting of curved and straight sections is formed along those interlayers.
The forms of earth and rock dam slippage are closely related to factors such as the dam structure, materials used in construction, properties of the foundation, and the operating conditions of the dam. Common shapes of sliding failure surfaces include: (1) curved sliding surfaces. When the sliding surface passes through the cohesive soil zone, its shape is usually a curved surface with a steep top and a gradually flatter bottom; in stability analysis, it is often replaced by an arc. ⑵Sliding line. It occurs frequently on the dam slopes of non-cohesive soils, such as thin-core wall dams and inclined-wall dams ； When part of the dam slope is submerged, the sliding surface often takes on a quasi-linear shape, with the turning point generally near the water surface. ⑶Composite sliding surface. Thick core dams or various soil dams composed of clay and non-clay soils form composite sliding surfaces. When there are weak interlayers in the dam foundation, due to their low shear strength, the sliding surface does not extend further downward; instead, it forms a composite sliding surface that consists of curved and straight sections along those interlayers.
The forms of earth and rock dam slippage are closely related to factors such as the dam structure, materials used in construction, properties of the foundation, and the operating conditions of the dam. Common shapes of sliding failure surfaces include: (1) curved sliding surfaces. When the sliding surface passes through the cohesive soil zone, its shape is usually a curved surface with a steep top and a gradually flatter bottom; in stability analysis, it is often replaced by an arc. ⑵Sliding line. It occurs frequently on the dam slopes of non-cohesive soils, such as thin-core wall dams and inclined-wall dams ； When part of the dam slope is submerged, the sliding surface often takes on a quasi-linear shape, with the turning point generally near the water surface. ⑶Composite sliding surface. Thick core dams or various soil dams composed of clay and non-clay soils form composite sliding surfaces. When there are weak interlayers in the dam foundation, due to their low shear strength, the sliding surface does not extend further downward; instead, it forms a composite sliding surface that consists of curved and straight sections along those interlayers.
1) Curve sliding surface: When the sliding surface passes through the cohesive soil area, its shape is usually a curved surface with a steep top and a gradually flatter bottom; in stability analysis, it is often replaced by an arc. 2) Sliding surfaces on slopes, which often occur in dam slopes made of non-cohesive soils. Such as in thin-core wall dams, inclined wall dams ； When part of the dam slope is submerged, the sliding surface is usually near-linear, with the turning point generally located near the water surface. 3) Composite sliding surfaces: thick core walls, or various soil dams composed of clay and non-clay soils form composite sliding surfaces. When there are weak interlayers in the dam foundation, due to their low shear strength, the sliding surface does not deepen further downward; instead, a composite sliding surface consisting of curved and straight sections is formed along those interlayers.
①Inadequate consideration was given to the impact of waves on damage; 2) The slope protection structure is unreasonable; 3) Quality control during the construction of the slope protection was inadequate – the dry-laid stones were not compact enough, with large gaps between them, and in some cases the structure even became elevated; 4) The materials used for slope protection were inappropriate; 5) During operation, a sudden drop in water level in the reservoir caused large gaps to form on the back side of the slope protection.
1) Curve sliding surface: When the sliding surface passes through the cohesive soil area, its shape is usually a curved surface with a steep top and a gradually flatter bottom; in stability analysis, it is often replaced by an arc. 2) Sliding surfaces on slopes, which often occur in dam slopes made of non-cohesive soils. Such as in thin-core wall dams, inclined wall dams ； When part of the dam slope is submerged, the sliding surface is usually near-linear, with the turning point generally located near the water surface. 3) Composite sliding surfaces: thick core walls, or various soil dams composed of clay and non-clay soils form composite sliding surfaces. When there are weak interlayers in the dam foundation, due to their low shear strength, the sliding surface does not deepen further downward; instead, a composite sliding surface consisting of curved and straight sections is formed along those interlayers.