What is the reason why the freshly watered dam has flowing water

There is a sand hole on the dam body, which leads to water leakage and seepage in the dam body.

Water seepage is a phenomenon that is difficult to avoid in the operation of hydraulic buildings, but it cannot be ignored. If the water seepage is within the allowable range of the design and does not affect the benefits and safety, it is normal water seepage and can not be treated. If the seepage pressure, flow rate or leakage volume is too large and exceeds the design allowable value, which threatens the safety of the project, it must be dealt with in time.

Therefore, when the leakage phenomenon is found, it is necessary to first conduct a thorough inspection, strengthen observation and analysis, judge whether the leakage is abnormal, and decide whether it needs to be treated. The principles of seepage treatment are:"Upper plug and lower row"。That is, first find seepage water in the upstream **, try to intercept it, and prevent water from entering the building; In the downstream, seepage drainage measures are taken to ensure that the seepage water does not bring out the soil particles, resulting in dam slope collapse pits and landslides.

Large-scale projects. It should be reported to the local **, that is, to the water conservancy bureau, and the repair should be solved in a timely manner.

Minor works, generally grouting blockage. It's a more general approach.

Grouting and grouting can be divided into chemical grouting and cement grouting.

The principle of treatment is to solve the problem thoroughly, not only to deal with the water leakage, but also to enhance the overall strength of the dam.

There are several common methods:

Rebuilding clay covering: This method is suitable for the single-layer foundation with good anti-seepage effect of the dam body, but the impervious layer is deep, and the premise is that there is clay near the dam area, and the reservoir needs to be emptied or cofferdam.

Construction. Otherwise, the method of throwing soil in the upstream water or filling muddy water can only be used, but the effect is poor.

Construct clay interception wall or interlocking concrete well column: this method is suitable for the situation that the dam body is of good quality, the impervious layer is shallow and the foundation is not dug to the impervious layer, and the condition is that the reservoir needs to be emptied for construction. When the permeable layer is sand, sandy loam or other weak layers, mortar sheet piles can also be used.

Construction of concrete impermeable walls: This method is suitable for the case of deep permeable layers.

Grouting curtain: This method is suitable for gravel or fine sand foundations, and the reservoir cannot be emptied for construction. According to the fillability of the base material, clay grout, cement grout, clay cement grout or chemical grout can be selected respectively.

Construction of pressure reducing wells or pressure seepage tables and drainage ditches: This method is suitable for foundation confined water.

The escape slope behind the dam is greater than the allowable value or there is a swamping phenomenon.

Ferroconcrete.

The dam will cause the corrosion and cracks of the steel bars to increase due to leakage, forming a hidden danger of collapse accidents.

In earthwork dams, long-term leakage can cause dam collapse. Plugging construction to prevent the occurrence of dam failure.

It has a lot to do with the location. The altitude of the Nasser Reservoir and the Aswan Dam is not much different from that of the lower Nile waterway, and if the water above is intercepted, the water level of the downstream river will drop. On the contrary, there is a big difference in the altitude between Sanmenxia and the Wei River, and the groundwater from the direction of Sanmenxia is hit in the groundwater system.