The water transport of loess slope and ecological treatment method
Technical field
The invention belongs to stability of slope and administer technical field, be specifically related to a kind of water transport and ecological treatment method of loess slope.
Background technology
The construction of infrastructure such as loess local highway, railway, water conservancy has formed a large amount of exposed side slopes inevitably, has influenced ecological environment on the one hand, in case rainfall will cause serious soil erosion on the other hand, even geological disaster such as landslide takes place.To this situation, many at present employing ecological protection improvement technology are improved slope stability, preserve the ecological environment simultaneously.The technology that protecting slope ecology is administered is with certain engineering and construction technology; On the basis that at first guarantees the side slope monolithic stability; On the side slope face, rebulid the certain thickness nutrition soil layer that is beneficial to plant growing; Create the good environment that is fit to plant growing, make domatic the going up of rock form the catch net that is interwoven with plant roots and stems together, play the effect of solid slope protection; Prevent domatic geotechnical body because of the erosion that suffers rainwater with wash away the loss that causes water and soil, and play the resultant effect of ecology recovering environment.
The precondition of zoology green-recovery technology is the side slope monolithic stability, and in the existing loess slope improvement method, often has such problem: loess body loose particles; Because rainfall; Soil body pore water pressure increases in the body of slope, and cohesive strength reduces, and shear strength reduces; The saturated yielding distortion possibly take place simultaneously, is very disadvantageous for the loess slope resistance to overturning.Adopt different schemes to different areas, geotechnical body, grade of side slope etc.; But these technical schemes all lay particular emphasis on the plant growing construction; Do not have to utilize comprehensively, fully the characteristics of loess slope self, ignored the ability of body self water outlet of loess slope slope, the equilibrium system that conserves water and soil.Can the water in the sloping body be discharged so provide a kind of, when guaranteeing slope stability, can make full use of again and discharge moisture cast side slope surface plant in the sloping body, a kind of like this process for comprehensively treating has the important project practice significance.
Summary of the invention
The water transport and the ecological treatment method that the purpose of this invention is to provide a kind of loess slope make the good and ecological sustainable development of loess slope resistance to overturning after the improvement.
The technical scheme that the present invention adopted is, a kind of water transport of loess slope and ecological treatment method carry out according to following steps:
Step 1, at first cut the earth to change at the side slope top and fill out, use sand, rubble or coarse sand to make permeable layer; On permeable layer, fill aquiclude then, aquiclude is that rammed earth forms; On aquiclude, cover the water and soil conservation layer, the water and soil conservation layer is the composite plant soil layer, and the composite plant soil layer uses the local soil of the seed, rhizome and the microorganism that contain eciophyte;
Step 2, on the side slope surface that is positioned at below the permeable layer, evenly and at interval hole and bury moisture migration pipe underground; The part that is positioned at cross section top 1/2~2/3 on each moisture migration pipe body has a plurality of water filtration eyeholes; Each moisture migration pipe body outside is surrounded by filtration beds, and each moisture migration pipe is positioned at the endcapped of side slope;
Step 3, latticed reinforced concrete skeleton frame is set along side slope surface; Also comprise a plurality of soil bolts; One end of each soil bolt and reinforced concrete skeleton frame connect and the other end is anchored in the inner soil layer of side slope, all plant plant in the grid of reinforced concrete skeleton frame.
The bottom surface top rade of permeable layer is 8 °~12 °, and the thickness of permeable layer is 27cm~33cm.
The thickness of aquiclude is 27cm~33cm.
Each moisture migration pipe top rade is 10 °~20 °.
Each moisture migration pipe is the UPVC plastic pipe, and the filtration beds of moisture migration pipe body external is gauze or geotextiles, and the end that moisture migration pipe is positioned at side slope uses the geotextiles sealing.
The concrete installation position of each moisture migration pipe is: the distance between adjacent in the horizontal direction two moisture migration pipe is 1.5m~2.0m, and the distance between adjacent two moisture migration of the in the vertical direction pipe is 1.8m~2.2m.
Secretion grouting between each moisture movement pipe mouth of pipe and its corresponding boring, the length of this grouting is 400mm~500mm.
Each soil bolt angle of declination is 15 °~25 °.
The equal correspondence of each soil bolt is bound up on the grid node of reinforced concrete skeleton frame; On the point midway between adjacent two soil bolts, all have moisture migration pipe installing hole on the reinforced concrete skeleton frame, each moisture migration pipe correspondence is arranged in the moisture migration pipe installing hole.
It is 10cm~20cm that the mouth of pipe of each moisture migration pipe all stretches out reinforced concrete skeleton frame.
The water transport of loess slope of the present invention and the beneficial effect of ecological treatment method are; Can realize intercepting water and blocking water of loess slope top, slope; Guarantee that the top, slope is stable, guide sloping body internal moisture to effluent simultaneously, supply with domatic plant growing required ecological environmental condition is provided.
Description of drawings
Fig. 1 is that the position of permeable layer among the present invention, aquiclude, water and soil conservation layer and moisture migration pipe concerns sketch map;
Fig. 2 is that the position of reinforced concrete skeleton frame and soil bolt and moisture migration pipe installing hole concerns sketch map among the present invention;
Fig. 3 is that the position of permeable layer among the present invention, aquiclude, water and soil conservation layer and soil bolt concerns sketch map;
Wherein, 1. permeable layer, 2. aquiclude, 3. water and soil conservation layer, 4. moisture migration pipe, 5. reinforced concrete skeleton frame, 6. soil bolt, 7. moisture migration pipe installing hole.
The specific embodiment
Like Fig. 1, Fig. 2 and shown in Figure 3, the water transport of a kind of loess slope of the present invention and ecological treatment method, carry out according to following steps:
Step 1, at first cut the earth to change at the side slope top and fill out, use sand, rubble or coarse sand to make permeable layer 1, the bottom surface top rade of permeable layer 1 is 8 °~12 °, and the thickness of permeable layer 1 is 27cm~33cm.The effect of permeable layer 1 is to be convenient to flow to side slope surface by the portion of water that ooze down on the top, slope through permeable layer 1.On permeable layer 1, fill aquiclude 2 then, aquiclude 2 is for rammed earth forms, and the thickness of aquiclude 2 is 27cm~33cm.On aquiclude 2, cover water and soil conservation layer 3, water and soil conservation layer 3 is the composite plant soil layer, and the composite plant soil layer uses the local soil of the seed, rhizome and the microorganism that contain eciophyte.Local soil is fit to the growth of local vegetation, and contains the seed, rhizome, microorganism etc. of eciophyte in the local soil, causes the clay fertilizer condition that is beneficial to plant growing to supply plant growth steady in a long-term, can form sloping top permanent vegetation cover.
Top, the loess slope slope soil body is generally particle looser and that weathering is serious, is unfavorable for that sloping body is stable, may be etched under the condition of raining, wash away along the slope and run off, and the side slope resistance to overturning is caused adverse effect.This part key technology is: permeable layer 1, aquiclude 2 and water and soil conservation layer 3 can form sloping top composite bed; Avoided top, side slope slope to produce the crack; The Free water row who gets into infiltration layer 1 supplies with vegetation moisture to domatic, reduces the quantity delivered that the moisture continuation is oozed down in the body of loess slope.
Step 2, on the side slope surface that is positioned at below the permeable layer 1, evenly and at interval hole and bury moisture migration pipe 4 underground, select the diameter of moisture migration pipe 4, aperture and hole depth when confirming boring according to moisture movement pipe 4 again according to local rainfall situation.Rainfall is the key factor that causes the side slope unstability, through moisture migration pipe 4 with water transport in the side slope to domatic, reduced on the one hand sloping in the pore water pressure of the soil body, improved the shear strength of the soil body, thereby helped the stable of sloping body; Moisture is domatic by flowing in the slope on the other hand, for the plant in the grid of reinforced concrete skeleton frame 5 provides indispensable growth conditions.
Moisture migration pipe will satisfy anticorrosion requirement and certain intensity condition on material.In the present embodiment, moisture migration pipe 4 is the UPVC plastic pipe, and the part that is positioned at cross section top 1/2~2/3 on each moisture migration pipe 4 body has a plurality of water filtration eyeholes, and the remainder of moisture migration pipe 4 bodys is used to catchment.Each moisture migration pipe 4 top rade is 10 °~20 °.Each moisture migration pipe 4 body outside is surrounded by filtration beds, and filtration beds is gauze or geotextiles.Each moisture migration pipe 4 is positioned at the end use geotextiles sealing of side slope, prevents that the soil body gets into the obstruction pipeline in the slope.
Wherein, the concrete installation position of each moisture migration pipe 4 is: the distance between adjacent in the horizontal direction two moisture migration pipe 4 is 1.5m~2.0m, and the distance between adjacent two moisture migration of the in the vertical direction pipe 4 is 1.8m~2.2m.
Situation such as downslide appear for fear of moisture migration pipe 4, the secretion grouting between each moisture movement pipe 4 mouth of pipe and its corresponding boring, and the length of this grouting is 400mm~500mm.
Step 3, latticed reinforced concrete skeleton frame 5 is set along side slope surface; Also comprise a plurality of soil bolts 6; One end of each soil bolt 6 and reinforced concrete skeleton frame 5 connect and the other end is anchored in the inner soil layer of side slope; Each soil bolt 6 angle of declination is 15 °~25 °, and length depends on actual need and decides.All plant plant in the grid of reinforced concrete skeleton frame 5, grass that plantation adapts to local climate, is prone to become to live, well developed root system and fertility are strong type or shrub.
At the loess slope growing plants on slope; Played the effect of bank protection and greening environment effectively, because rainfall is to bring out one of key factor of side slope unstability, and plant is through absorbing and evaporate moisture in the sloping body; Reduced the pore water pressure of the soil body; Increase the cohesive strength of the soil body, thereby improve the shear strength of the soil body, also help stability of slope.Simultaneously, because flourishing, intensive, interspersed, the networks of root system of plant etc. also help to prevent the weathering off of side slope.Conversely, also help the recovery of slope ecological environment, thereby move towards benign cycle.
The domatic support pattern of the present invention uses reinforced concrete skeleton frame 5 and soil bolt 6 combined supportings.Soil anchor bolt has advantages such as accounting for place, reduction of erection time, reduction cost less, is a kind of rod member that bears, and the supporting soil layer is stable in order to keep, and can stop effectively on every side that soil layer caves in, displacement and sedimentation.Soil bolt generally is made up of anchor head, free section and anchoring section three parts.Wherein anchoring section bonds together the body of rod (presstressed reinforcing steel) and the soil body anchoring body that forms anchor pole with cement paste or cement mortar.Soil anchor bolt expose the anchor pole part, free section all should be done the durability of corresponding preservative treatment measure with the assurance anchor pole with anchoring section.Operations such as the work progress of soil anchor bolt comprises pore-forming, lays pull bar, grouting and tensioning fixation.
Each soil bolt 6 equal correspondence is bound up on the grid node of reinforced concrete skeleton frame 5; On the point midway between adjacent two soil bolts 6, all have moisture migration pipe installing hole 7 on the reinforced concrete skeleton frame 5, each moisture migration pipe 4 correspondence is arranged in the moisture migration pipe installing hole.At this moment, moisture migration pipe 4 is positioned at the midpoint of adjacent two soil bolts 6, has maximum cast area.
The mouth of pipe of each moisture migration pipe 4 all stretches out reinforced concrete skeleton frame 5 and is 10cm~20cm, and to drop down onto the bottom domatic so that migrate out moisture.