Exploration On Factors And Arrangement Principle Affecting The Working Effect Of Relief Wells

All kinds of seepage control measures have been used in the levee seepage resistance project, among which the seepage drainage measures such as relief wells and drainage trenches are most widely used. However, because of the effect of relief wells would weaken with time and be affected greatly by hydrogeological conditions, people tend to choose the cutting seepage measures over relief wells. In this case, exploration on factors that affect the working effect of relief wells is of necessity.Factors have impact on the working effect of relief well includes the internal factors, such as well radius, well spacing, head loss and penetration etc, and external factors including seepage paths, water level, permeability of superstratum and distribution of hydrological. The past study on the effect of relief wells mainly focus on internal factors, but few on external factors. It is proved by engineering practice that external factors also affect the effect of relief wells significantly. Not enough understanding towards the influence of external factors leads to a rigidly conventional pattern on arrangement of relief wells, which greatly limits the effect of relief wells.By employing analytic solutions of indefinite length relief wells and horizontal two-dimensional seepage finite element program, the influence of internal and external factors to relief wells is studied in this paper, and based on which the arrangement principle of relief well is discussed. The study is carried out in following procedures:(1) By employing analytic solutions of indefinite length relief wells and horizontal two-dimensional seepage finite element program, the influence of internal and external factors to relief wells is studied. And the arrangement principles, such as the using condition of relief wells, principle of axis position choice, design of well height and arrangement medthods under distribution of hydrological, are discussed.(2) Basic on the relief wells arrangement practice in seepage resistance project of beijiang dike, the arrangement principle of relief wells under complicatied hydrogeological conditions is further discussed by means of horizontal two-dimensional computational model.(3) Finally, discussion on the optimization of the arrangement of relief wells used in chaozhou water conservancy project is made by using the arrangement principle obtained in former chapters.