Proposing solutions to calculate water level lowering for underground works in different hydrogeological conditions

Abstract

Currently, during the construction of high-rise buildings with basements, or underground works below ground level in our country, phenomena such as the bottom of the foundation pit, sand flowing on the side of the diaphragm wall, and ground subsidence occur, ... causing serious damage to people and property. These phenomena often occur during the pumping process to lower the groundwater level. One of the reasons leading to the above phenomena is that the assessment of hydrogeological characteristics of the construction area is unclear, so design calculation methods are applied that are not suitable for each application condition. In addition, during the operation of the drainage systems to lower the underground water level, it has not been strictly controlled, so when the water level is lowered too much (exceeding the allowable limit), the construction unit has no remedial measures. appropriate and timely. In this article, the authors provide formulas to calculate the flow corresponding to the water level lowered according to design applicable to complete and incomplete well conditions, applied in hydrogeological conditions. different literature. In addition, the authors provide steps to calculate pump flow when designing and propose a flowchart to control the design and operation of the drainage system to lower the groundwater level with the hope of helping implementation units. The company has a more general view of the process of calculating and designing the dry drain system, thereby being able to operate the system more safely.