Because of several historical reasons, there are heavy defects of quality level of powerhouse concrete placement for Cascade I Hydropower Station at Yunlonghe River. Especially,there exist some cellular parts and ballast-surface in the concrete surface of the project. In some places,the water leakage is much higher.
The measurement of actual works also explained that the use of compound geotextile in rock fill dam surface can reduce the amount of leakage water by 60%, the effects of imperviousness are obvious.
Based on collecting leakage data and making leakage investigation, according to summarize the reason for the network leakage, management measures were proposed, and also the technical measures for reducing leakage frequency and leakage quantity were presented from the view point of design, construction and maintenance.
1underwater. It analyzed the reasons influencing on leakage amount change by analysis of the leakage quantity during construction. The treatment effect was analyzed by the leakage condi-tion after treatment.
The cracks in the dam block No. 2 at Mianhuatan dam were splitting cracks, and the leakage quantity at the corresponding area in the gallery was up to 110 L/min and had been taken measures.
1underwater. It analyzed the reasons influencing on leakage amount change by analysis of the leakage quantity during construction. The treatment effect was analyzed by the leakage condi-tion after treatment.
Equations are given that allow calculating water leakage and the part of the hydrodynamic pressure that is caused by water leakage from layer to layer.
For concrete hydrogeological conditions, estimates are given for the hydrodynamic pressure and its part determined by water leakage between aquifers and from layer to layer in the case of ascending and descending groundwater flows.
It is necessary to apply longitudinal prestress to prevent crack and water leakage to transverse joints, where Design procedure for the transverse joints, assuming full-prestressing, is proposed.
The driving force for fluid inclusion deformation involves two related mechanisms: plastic deformation of hydrolytically weakened wet quartz in the healed fracture, and water leakage associated with preexisting and strain-induced dislocations.
During copper accumulation, a leakage of UV-absorbing compounds and inorganic phosphate was observed; this did not occur with lead, whereas with cadmium a small amount of leakage of inorganic phosphate was detected.
The strong correlations among major cations and chloride suggested that even a small amount of leakage from salty flushing water pipes can significantly affect the groundwater chemistry.
The amount of leakage had more effect on the model simulation of pressure heads than the way leakage was considered, localized or distributed along the laterals.