砂墙
1.Through the field observation and comparative seism-geologic studies, many seism-genesis soil-layer structures such as vibration-liquefied sand vein, vibration-liquefied sand dyke, sandy cobble dyke by fissure filling, seismic fall mass, seismic intra-layer fault and seism-settlement structures etc. were recognized .
2.In this paper, using the nonlinear finite element analysis, the stress-strain in the Hua Liang Ting Earth Dam is calculated to investigate the cause of longitudinal cracks in the watertight core.
3.Practices show that the compressive strength, the modulus of elasticity, the permeability coefficient and the compactness of concrete obtained respectively by the compaction method, the unconfined compression static compaction method, the sand trenching and filling method, and nuclear densimeters meet the requirement of design, and the mixing proportion of concrete of the side-wall is reasonable.
4.So far as the mixing material for building the earthrock fill dam with clay core for Shiquanhe Hydropower Station is concerned, the effect from the variation of the sand content for the filter material on the maximum dry density and the relevant parameters are to be determined within the variation area of the mixing mass ratio of (46~54):(54~46) through this experiment, due to the max, dry density is largely influenced by the mixing ratio of both the lifter material and the clay and the sand content of the filter material, so as to determine the actual filling compactness of the mixing material of the core.
5.A brief introduction is given to the treatment of the Zeya dam foundation,principles of seepage control and design of the concrete face rockfill dam of the Zeya reservoir.As for the excavation of the sand-gravel zones,except the toe slab and its 1/9 bottom width down stream,the alluvial layers are excavated to the micro-weathered rocks,while the other sections remain unexcavated.Regarding to the treatment of the fracture zones,concrete filling is used for the toe slabs and semi-permeable materials are used for other section.According to the construction characteristics,a filter is placed in the down stream embankment foot.To improve the integrity of the dam foundation and anti-seepage capability consolidation grouting and curtain grouting are adopted.As a result safety,economic benefit,convenience in construction and good performace are achieved.
6.The study indicated that asphalt concrete core wall of Majiagou reservoir seeped terribly because of the fissure appearing between ZK7 and ZK7-1 and between ZK7-2 and ZK8. A central water leakage path was found out along the fault of F16 to the right sandless pipe in the right dam of Jicun hydropower station.
