CN205907658U - Be used for anti - structure that seeps water of concrete -faced rockfill dam construction time dam body - Google Patents

Abstract

The utility model discloses a be used for anti - structure that seeps water of concrete -faced rockfill dam construction time dam body, including constructing the blind drainage ditch in the dam body bottom, blind drainage ditch's the upper reaches are located the rear portion of dam body transition material, blind drainage ditch's low reaches lie in the low reaches dam facing, and elevation lower department in dam body low reaches sets up the sump pit, and it utilizes in the french drain water automatic discharge dam body infiltration of turning over of flowing automatically, do not destroy the seepage prevention structure at the upper reaches, and the later stage is without the shutoff.

Description

For face dam construction time dam body reverse osmosis water-bound

Technical field

This utility model is related to Hydraulic and Hydro-Power Engineering concrete dam field, is used for face dam construction time dam in particular to a kind of Body reverse osmosis water-bound.

Background technology

Based on the feature that CFRD dam material subzone and waterpower are excessive, the permeability of each area dam material is from upstream Downstream it is gradually increased, thus to control seepage stability, but, so can not protect the reverse consolidation pressure pair of bottom-up trip Bedding material, the solid slope protective layer in upstream and the destruction having poured panel, therefore bear seepage uplift (osmotic pressure) in construction time dam structure Ability be limited.CFRD during Construction, when upstream, excavation of foundation pit depth is larger, and construction water and rainwater penetrate into Dam body cocurrent upstream foundation ditch, all can form reverse head, act on completed bed course, the solid slope layer in upstream and concrete surface Plate.

Level of tail water 7m higher than upstream is found, reverse water pressure power causes bed course area damage envelope long in the construction of North-West Exit panel Reach 60m, more than 20 spring occurs, some fineves are flushed away, the solid slope in upstream protective layer produces very long crack.Tianshengqiao-I High concrete panel rock-fill dams test result illustrates, before panel pours, in the case of reverse osmotic pressure, the wide bed course of 3m can hold The inverse osmosis hydraulic gradient being subject to only about 1.2～1.4, when reversely water-head only has 3.6m～4.2m accordingly, you can produce pipe Gush destruction.The test of coral small stream CFRD also illustrates, before panel pours, in the case of inverse osmosis, 2m is wide Horizontal bed course critical hydraulic is about 0.6～1.5 than fall, destruction hydraulic gradient about 2.17～3.25, only about 2.5m～3.7m Reversely during water-head, it is possible to produce piping, native transitional type is destroyed with stream.

By the way of typically taking out lower row in the method for sump at present, such as Shuibuya Concrete Face Rockfill Dam, this dam Height of dam 233m, upstream and downstream water level discrepancy in elevation 26.7m, for ensureing that bedding material and extrusion side wall are not destroyed by inverse osmosis current, adopt Take and two gullys have been set in the main rockfill area apart from toe board rear portion 25m, shaft bottom has been sitting on basement rock, and draining # diameter 2m, by 2 Layer diameter is respectively the circular bar-mat reinforcement composition of 2m and 3m, bar diameter 20mm, spacing 10cm, wraps up in densification network outside bar-mat reinforcement.Face Before plate pours, along extrusion side wall upstream face by draining steel pipe separate, socket pvc pipe in case panel construction when draining.One phase panel Block drain pipe after the completion of pouring, when bedding fills to draining well head elevation before dam, proceed by gully closure.

Tradition solves CFRD during construction dam body seepage uplift mainly a following problem:

(1) construction is complicated

The steps such as traditional dam body reverse osmosis water process is typically directed to that drain pipe is embedding, water-pumping/draining and later stage closure, construction Complex.Taking Yunnan Cai Shi Tan reservoir as a example: this CFRD height of dam 101.8m, in the construction of rear dam slope water stop After the completion of, maximum stage difference reaches 17m in front and back, and dam foundation subsoil water adds the precipitation at dam site position through observation in 4.8～13.9l/s Conflux, construction when before dam slope reverse osmosis phenomenon more prominent.Treatment measures are: when 1. starting section enrockment body construction, in dam The zinc-plated floral tube of pre-buried 3 diameter 100mm does ejectment and processes.2., before panel construction, lay 3 in 1aa Colophonium sand lump bottom and fill Transverse drainage implemented by the nonwoven stringing filling out rubble, takes and enter in the embedded 4 groups of iron sheet water filtering tanks of nearly lower panels and water pump after concentration The water-pumping/draining of row panel construction time, before dam, clay and bedding implement closure when filling.3. in the pre-buried no sandpipe of downstream dam slope, by Dam water-pumping/draining from inside to outside, makes water level in the dam foundation be less than interior water level and is less than 1550m elevation, upstream clay material, rock ballast material fill and reach After 1560m elevation, operation of drawing water in stopping no sandpipe.

(2) if closure is not thorough, seepage channel may be formed on dam body

CFRD relies on rockfill supporting ＆ stablizing, depends on the concrete of upstream dam facing 0.3～1m Thin plate antiseepage.Panel, plate seam, panel and periphery ground seam collectively form seepage prevention system.At present typically using upstream The mode of draining processes dam body seepage uplift problem, so needs in panel or buries water pipe in toe board, thus can be Weak part is defined, so the later stage must be blocked, if closure quality reaches not in above-mentioned rock seepage prevention system To requiring, then may form seepage channel to threaten dam safety in dam body upstream.

(3), when upper pond level is higher, need to draw water from sump

Traditional method typically from upstream drainage, but, plinth foundation is typically relatively low, due to construction drainage and two sides massif The impact of draining, upstream Water Level in Foundation Pit is generally greater than sump, so pump drainage measure must be adopted, time-consuming.

Therefore it provides a kind of connection and reasonable arrangement, compact the seeming very for face dam construction time dam body reverse osmosis water-bound of linking It is necessary.

Content of the invention

Problem to be solved in the utility model seeks to provide a kind of connection and reasonable arrangement, is connected compact applying for face dam Duration dam body reverse osmosis water-bound, it is automatically drained out dam body reverse osmosis water using water body in french drain, does not destroy the antiseepage of upstream Structure, the later stage is without closure.

For solving above-mentioned technical problem, the one kind designed by this utility model is used for face dam construction time dam body reverse osmosis water and ties Structure, including the weeper drain being built in dam body bottom, the upstream of weeper drain is located at the rear portion of dam body transition region, weeper drain Downstream is located on the dam facing of downstream, arranges catch pit at the elevation of dam body downstream.

Preferably, weeper drain from upstream to the slope in downstream than for 0.5%.As such, it is possible to using water body in weeper drain It is automatically drained out dam body reverse osmosis water.

Further, the cross section of weeper drain is isosceles trapezoid.

Further, the upper bottom of isosceles trapezoid and the length gone to the bottom ratio is for 1:5.So, weeper drain is more firm, simultaneously The pressure of dam body can be preferably minimized.

Dao Yekan Secondary Hydropower Station (thaukyegat (2)) is located at stannum Tang of Burma (sittaung) river valley, Toungoo (taungoo) 21km to the east of city, installed capacity is 120mw, and average annual energy output is 6.047 hundred million kw h.Dao Yekan power station is big Dam is CFRD, 133 meters of crest elevation, 91 meters of height of dam.This utility model method is in Dao Yekan Secondary Hydropower Station Upper test, empirical tests, successfully solve following problem:

First, building gutter, easy construction using original bed lower position；

Second, due to downstream draining, not destroying " upstream apron+panel+toe board+bedding material+Transition Materials+sealing " The rock seepage prevention system being formed, so do not need other close measure after the completion of construction；

Third, dam body infiltration is flow in Excavation of Downstream Foundation Pit certainly, it is possible to use the drainage system in former base hole draws water it is not necessary to join The personnel of the standby other facility that draws water；

Fourth, having significant economic benefit, comparing with traditional drainage pattern, saving 1,800,000 yuan of fund, save the duration 2 months；

Fifth, the deformation of face dam and seepage flow tend towards stability substantially, it is seated in Highly weathered soft rock in plinth foundation major part Under conditions of, maximum settlement about 0.8m, less than 1% height of dam magnitude, maximum leakage is less than 10l/s, reaches advanced world standards.

Brief description

Fig. 1 is used for the structural representation of face dam construction time dam body reverse osmosis water-bound for this utility model；

Fig. 2 is the a-a cross section structure diagram of Fig. 1；

Fig. 3 is the b-b cross section structure diagram of Fig. 2；

Fig. 4 is the c-c cross section structure diagram of Fig. 2；

Fig. 5 is the d-d cross section structure diagram of Fig. 2；

Fig. 6 is the e-e cross section structure diagram of Fig. 2.

Wherein, dam body 1；Weeper drain 2；Dam body transition region 3；Downstream dam facing 4；Catch pit 5；The thickness l1 of protective layer；Fill out Fill thickness l2.

Specific embodiment

Below in conjunction with the drawings and specific embodiments, this utility model is described in further detail, but this embodiment should not This is interpreted as to restriction of the present utility model.

Shown in figure for face dam construction time dam body reverse osmosis water-bound it is characterised in that: include be built in dam body 1 bottom The weeper drain 2 in portion, the upstream of weeper drain 2 is located at the rear portion of dam body transition region 3, and the downstream of weeper drain 2 is located at downstream dam On face 4, catch pit 5 is set at dam body 1 downstream elevation.

Weeper drain 2 from upstream to downstream slope than for 0.5%.

The cross section of weeper drain 2 is isosceles trapezoid.

The upper bottom of isosceles trapezoid and the length gone to the bottom ratio is for 1:5.

During utility model works, for the building method of face dam construction time dam body reverse osmosis water-bound, walk including following Rapid:

1) excavate weeper drain at the elevation of riverbed bottom, if weeper drain 2 bottom of trench is higher than basement rock top, being expected with 3a will It is backfilled to weeper drain 2 Bottom Altitude less than the position of weeper drain 2 bottom of trench, if as shown in figure 3, weeper drain 2 bottom of trench is low In basement rock top, then it is excavated to weeper drain 2 Bottom Altitude, as shown in Figure 4；

2) fill weeper drain with 3d material again, 3d material filling thickness l2 is controlled to 200cm, and as shown in Fig. 3, Fig. 6,3d material is filled out Build layer and both sides other filler and synchronously fill；

3) by 3d, laying 3a material protection above position is expected to site operation road, laying 3a expects the thickness l1 of protective layer It is controlled to 150cm, as shown in Figure 3, Figure 4；

4) roll, sprinkle water, control number of rolling to be ten times, control watering amount by the 3d that filled expect volume 15～ 20%.

Described 3a material is the fresh rock mass of mild windization that block footpath is 30～50cm, and described 3d material is block footpath is the micro- of 50～80cm The fresh rock mass of air slaking.

Reverse osmosis water is automatically drained out dam body by weeper drain, enters catch pit.

The content not being described in detail in this specification, belongs to prior art known to those skilled in the art.

Claims (4)

1. a kind of for face dam construction time dam body reverse osmosis water-bound it is characterised in that: include being built in the row of dam body (1) bottom Water french drain (2), the upstream of described weeper drain (2) is located at the rear portion of dam body transition region (3), the downstream of described weeper drain (2) On downstream dam facing (4), setting catch pit (5) at the elevation of dam body (1) downstream.

2. according to claim 1 for face dam construction time dam body reverse osmosis water-bound: it is characterized in that, described draining is blind Ditch (2) from upstream to downstream slope than for 0.5%.

3. according to claim 1 and 2 for face dam construction time dam body reverse osmosis water-bound it is characterised in that: described row The cross section of water french drain (2) is isosceles trapezoid.

4. according to claim 3 for face dam construction time dam body reverse osmosis water-bound it is characterised in that: described isosceles ladder The upper bottom of shape and the length gone to the bottom ratio is for 1:5.