荆江沙基堤防的管涌险情抢护与防治

介绍管涌险情的成因，“外截内导”的指导原则，“围井导滤”和“蓄水反压”的抢护方法，“出清水不带泥沙”的管涌险情控制标志．防止管涌的主要方法是前堵后排（ 导） 或前堵后压，以排为主，截、排、压兼施，延长渗径，改变堤基的渗流状态．采用填筑堤内平台，使覆盖层的厚度与水头差相等，是防止管涌险情发生的有效方法．

Piping Control for Embankment on Sand Foundation of Jingjiang

The causes of piping in the embankment of Jingjiang is introduced.The principle for preventing piping is “Inclosure outside the basin and diversion in the inner basin”.The measures such as flood diversion,and flood water storage to create a counter pressure,are taken.Clear flow is the mark of controlled piping.The main method for preventing piping is “Inclosure infront of the embankment and diversion behind the embankment with the stress placed on diversion”.In all,enclosure,diversion and creation of a counter pressure are adopted in the same time to prolong the seepage path and change the seepage pattern.The construction of platforms on the inner side of the embankment to make the covering strata thickness equal to the difference of water head is an effective way to prevent piping.