Construction method for treating flowing sand of deep foundation pit slope

Abstract

The invention discloses a construction method for treating flowing sand of a deep foundation pit slope. The essential significance of the construction method is to treat the stagnant water of the deepfoundation pit slope. Since releasable flowing can only occur to a geological sand layer with water under certain conditions inducement, the sand layer is naturally stopped if the water in the sand layer is discharged. The stagnant water in the geological sand layer is formed naturally, the conditions and reserves are both different, and the gushing potential of the flowing sand is different as well. According to the method, two measures are adopted according to the different gushing amounts, wherein the first measure is to use a reverse drainage water filtering channel and is suitable for the situation that the gushing of the flowing sand is small and slow; and the second measure is to use the reverse drainage water filtering channel and infiltrating wells, and is suitable for the case that the gushing of the flowing sand is large and the related section is long. The first measure of using the reverse drainage water filtering channel is characterized by comprising the steps of drilling a plurality of downwardly inclined water through holes in the edge of a trough at the trough slope where the flowing sand gushes, and intercepting the flowing sand water flowing into the foundationpit and draining the flowing sand into the sand layer of the next layer through filtering; and the second measure of using the reverse drainage water filtering channel and the infiltrating wells is characterized in that the water filtering channel is arranged at the trough slope and the plurality of infiltrating wells are additionally arranged at a place slightly away from the trough opening.

Description

technical field [0001] Engineering technology Suitable for grading foundation pits or supporting pile foundation pits [0002] technical background [0003] Quicksand on the side slope of deep foundation pit refers to that during the excavation of large or relatively large deep foundation pits, the deepest groove bottom of the foundation pit has no water, and the slope or groove wall at the upper part of the foundation pit (4-6m from the surface) is partially The phenomenon of quicksand occurs due to the presence of water outside the tank. When the quicksand gushes out seriously, it will cause the side slope of the foundation pit to landslide or the back of the groove wall to collapse, especially when there is a drop between the quicksand gushing point and the excavation depth, the quicksand gushes out very quickly, and the expansion speed of the landslide or collapse is also very fast. If it is not stopped immediately, it will constitute a major safety hazard or cause a maj...

AI Technical Summary

Problems solved by technology

But this method still has defects: at first, the biggest disadvantage is that it is very unfavorable to foundation pit excavation and slope protection (wall protection), because the water outlet point is on the top of the foundation pit, and along with the depth of the earthwork, the water collecting ditch, water collecting The pit also needs to be modified several times with the depth, which increases the consumption of machinery and labor and affects the progress of excavation and the follow-up of slope protection.

The second is that the fertilizer tank will eventually be occupied as an open drainage ditch and a sump. This facility will have a certain inconvenient impact on the construction of the underground project.

In addition, if the root of the slope is soaked in water for a long time, it is easy to induce a landslide on the slope if it is not properly prevented; if the construction period of the underground project is too long, more labor and power consumption will be added.

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