Plugging and dredging structure of flood drainage facility of tailing pond
Technical Field
The utility model relates to a shutoff of tailing storehouse flood discharge facility, dredge structure can extensively be applicable to the old flood discharge system of tailing storehouse, be about to close the improvement of tailing storehouse flood discharge system.
Background
The flood drainage system of the tailing pond mainly comprises a water inlet building, a water outlet building and energy dissipation facilities which are connected. The water inlet building is mainly a common drainage vertical shaft, a drainage chute and the like, wherein the drainage chute is divided into an arch cover plate chute and a flat cover plate chute; the water outlet structure comprises a culvert, a drainage tunnel, a spillway and the like. The tailing pond flood drainage system breaks down, and unable normal operating can cause the unable effectual earial drainage of flood, and the water level can sharply increase in the storehouse, causes the flood to spill over the dam crest of tailing dam, because the impact force of flood is very big and the stress surface if surpass the stress that bears, will lead to the tailing dam to appear breaking the phenomenon of dam, brings the calamity for the people's lives and property in storehouse dam low reaches to cause serious environmental protection accident. Tailings pond safety incidents caused by flood discharge system failure (whether in use or blocked) account for almost 50% of the total incidents. Some tailings accumulation dams are designed to have the height of more than 100m, flood drainage tasks are sequentially undertaken by several stages of flood drainage systems, and before a new stage of flood drainage system is formally started, the old flood drainage system needs to be safely and effectively plugged. In addition, after the tailing pond runs to the designed service life, the tailing pond needs to be closed, and for the tailing pond to be closed, the reliability cannot be guaranteed due to the effects of years of erosion, heavy pressure, shearing, surface subsidence and the like on the original flood drainage system. In order to effectively put an end to and reduce the hidden danger and risk brought by the uncertainty of the quality of the originally buried drainage structures, the hidden danger and risk are mainly expressed in the aspects of collapse, damage, sand leakage and the like of a flood drainage system, the old flood drainage system also needs to be safely and effectively plugged, and the stability and the downstream safety of the closed tailing pond are ensured. Therefore, whether the flood drainage system of the tailing pond can be safely and effectively plugged or not directly influences the safety and danger of the tailing pond.
At present, the blocking of the drainage system of the tailing pond has two methods, one is flexible blocking, namely, geosynthetic materials with the reverse filtration effect, such as non-woven geotextile, sand gravel, broken stone and other artificially synthesized or natural materials are used as a blocking body for blocking, and the drainage system after blocking can intercept tailing particles to enable the tailing particles to be deposited before or in the blocking body, and water can permeate through the blocking material. However, as the sediment thickness of the tailings is increased day by day, the water permeability of the plugging body is poorer and poorer, the water seepage amount is reduced gradually, and the purpose of plugging is finally achieved. The second is rigid plugging, which is plugging by rigid materials such as plain concrete, rubble concrete or grouted block stone and the like, and requires tight plugging and no water leakage.
Rigid plugging and flexible plugging are used, and the final purpose of the method is to successfully plug the flood drainage system. According to the two plugging principles, rigid plugging is that after self-plugging is finished, tailings and water seepage are blocked in front of a plugging body, and the outlet of a flood drainage system is required to drip water without leakage; the flexible plugging means that after plugging is finished, along with the time, inverted filter bodies such as broken stones, gravels, non-woven geotextiles and the like are gradually deposited by fine-particle tailings, so that the water permeability of the plugging body is increasingly poor, and finally the tailings and the water seepage are blocked in front of the plugging body. No matter which kind of shutoff mode is adopted, the drainage system is by the shutoff back, because there is the high water level in the tailing storehouse, leads to having formed huge flood peak in shutoff body department, and under this kind of high flood peak effect, the shutoff body is bearing huge water pressure, and along with the time lapse, this strand of water pressure can break the shutoff body by oneself, leads to the shutoff to become invalid, has very big potential safety hazard, probably brings serious consequence even.
In order to solve the leakage problem of the flood drainage system of the tailing pond, the reason of the leakage of the flood drainage system of a certain tailing pond is found through investigation and analysis in the text of 'research on leakage plugging measures of the flood drainage system of the tailing pond' published in 7 months in 2009. Aiming at the water stop failure of the expansion joint in the flood drainage system, the leakage stopping king and the high polymer material are matched for grouting, and meanwhile, the leakage point of the wall of the concrete flood drainage pipe is blocked by water glass-cement. The whole plugging construction is short in duration and good in effect, and potential safety hazards of the tailing pond due to leakage of a flood drainage system are eliminated. However, the plugging measure has high cost of plugging materials, is only suitable for local plugging of leakage points, and is not suitable for the treatment of old drainage systems of the tailing pond, namely the drainage systems of the tailing pond to be closed.
Disclosure of Invention
The utility model aims at providing a tailing storehouse flood discharge facility's shutoff, dredge structure in order to solve the above-mentioned problem that current rigidity shutoff and flexible shutoff exist respectively exactly to stop or reduce behind the shutoff because of the shutoff body bears huge water pressure and lead to potential safety hazard and environmental risk that the shutoff became invalid and probably bring.
In order to realize the above object of the utility model, the utility model relates to a shutoff of tailing storehouse flood discharge facility, dredge the structure combines rigidity shutoff and flexible shutoff mode, based on "stifled" dredge "principle, adopts following technical scheme:
the utility model relates to a shutoff of tailing storehouse flood discharge facility, dredge structure, including drainage chute, drainage culvert, the connecting well that sets up between drainage chute and drainage culvert. In addition, it still includes drainage chute and the block structure of connecting well, drainage culvert's anti-straining and drainage structures:
1) drainage chute and plugging structure of connecting well
The upper cover of the drainage chute is covered with a chute cover plate, and non-woven geotextiles are filled in the gaps between the chute cover plates and the gaps between the chute cover plate and the drainage chute so as to prevent tailings from entering the drainage chute through the gaps and realize 'water leakage and sand leakage prevention'; a stone block section, a gravel section and a melon and rice stone section are respectively arranged in the drainage chute from bottom to top, and stone blocks are also filled in the connecting well and are connected with the stone block section in the drainage chute; the length of a blocking section formed by the stone blocks, the broken stones and the melon and rice stones in the drainage chute is 1/3-1/2 of the total length of the drainage chute, and during the specific implementation process, less and uniform aggregates (stone blocks, broken stones or melon and rice stones) are poured into the drainage chute every time, so that the accumulation phenomenon is prevented; arranging an integrated prefabricated top cover plate at the water inlet of the drainage chute, wherein the section size of the top cover plate is required to completely wrap the water inlet of the drainage chute; non-woven geotextile is filled in a gap between the water inlet of the drainage chute and the top cover plate; in the lump stone section, the mass content of the lump stones with the grain size of 5-25 cm in size fraction is more than or equal to 95 percent; in the gravel section, the mass content of gravel with the grain size of 0.5-2 cm in size fraction is more than or equal to 95 percent; in the melon and rice stone section, the mass content of melon and rice stone with the grain size of 0-0.5 cm is more than or equal to 95%.
2) Reverse filtering and draining structure of drainage culvert
Arranging an inverted filter body which is 5-10 m long and is composed of a rock block section, a broken stone section and a melon and rice stone section from the outlet of the drainage culvert to the upstream; in the gravel section, the mass content of gravel with the grain size of 0.5-2 cm in size fraction is more than or equal to 95 percent; in the melon and rice stone section, the mass content of melon and rice stone with the grain size of 0-0.5 cm is more than or equal to 95 percent; a certain number of PE drainage pipes for guiding and draining water seepage in the drainage chutes and the drainage culvert are pre-embedded in the drainage culvert, the PE drainage pipes are distributed in a row and in a layered manner, and the specific number is comprehensively determined according to the inner diameter of the drainage culvert and the water quantity to be guided and drained; the PE infiltration discharge pipe is a perforated pipe, 2 layers of non-woven geotextile are wrapped on the periphery of the PE infiltration discharge pipe, and the PE infiltration discharge pipe is firmly tied by galvanized iron wires; and arranging a closed concrete retaining wall at the outlet of the drainage culvert, wherein the concrete grade of the retaining wall is not less than C30, the foundation is required to be located on an old soil layer and to be deep into the ground by 1.5-3 m, and the section size of the retaining wall is required to completely wrap the outlet of the drainage culvert. The blocking wall is adopted for blocking, and the PE seepage drainage pipe is used for assisting, so that the reverse filter body is prevented from being flushed out of the drainage culvert by the gradually increased water pressure along with the time.
In order to effectively plug the drainage chute and take the plugging cost into consideration, the length of a plugging section (a lump stone section, a broken stone section and a melon and rice stone section) in the drainage chute is 1/3-3/7 of the total section length of the drainage chute.
Further, in the plugging structure of drainage chute and connecting well, if the length of the plugging section in the drainage chute is L, then: the length of the block stone section is 0.40-0.55L; the length of the crushed stone section is 0.25-0.40L; the length of the melon-rice stone section is 0.15-0.25L.
Furthermore, in the reverse filtering and seepage discharging structure of the drainage culvert, if the total length of a reverse filter body consisting of the stone block section, the broken stone section and the melon and rice stone section is l, then: the length of the stone block section is 0.40-0.50 l, the length of the broken stone section is 0.25-0.40 l, and the length of the melon-rice stone section is 0.15-0.25 l.
In a specific implementation, the specification of the non-woven geotextile is selected to be 400g/m2The specification of the PE seepage drainage pipe is selected to be 75 mm.
The utility model relates to a shutoff of tailing storehouse flood discharge facility, dredge behind the structure adoption above technical scheme, have following positive effect:
(1) the drainage chute and the drainage culvert are plugged by the stones, the broken stones and the melon and rice stones, so that the plugging engineering quantity is small, and the engineering cost is low;
(2) the plugging method is simple and has strong operability;
(3) the plugging mode respectively absorbs the advantages of flexible plugging and rigid plugging, and the safety is good;
(4) the plugging principle is based on the plugging and dredging principle, and the practicability is strong;
(5) the uncertain potential safety hazard caused by plugging failure is avoided, and the social benefit and the economic benefit are remarkable.
Drawings
FIG. 1 is a sectional view of a drainage chute and a plugging structure of a connecting well according to the present invention;
FIG. 2 is a cross-sectional view of the chute cover plate and the drainage chute according to the present invention;
FIG. 3 is a sectional view of the reverse filtration and drainage structure of the drainage culvert of the present invention;
the reference signs are: 1-chute cover plate; 2-non-woven geotextile; 3-block stone section; 4-a gravel section; 5-melon rice stone segments; 6-top cover plate; 7-PE drainage pipe; 8-connecting well; 9-blocking wall.
Detailed Description
For better describing the utility model, the plugging and dredging structure of the flood discharging facility of the tailing pond is described in detail with the attached drawings.
Combine certain iron ore tailing storehouse to close to use actually in the storehouse design, shown by figure 1 the utility model discloses a drainage chute and the block structure section view of connecting well combine figure 2, figure 3 to see, the utility model relates to a shutoff of tailing storehouse flood discharge facility, dredge the structure, including drainage chute, drainage culvert, the connecting well 8 that sets up between drainage chute and drainage culvert, still include drainage chute and connecting well block structure, drainage culvert's the anti-straining and the drainage structure of oozing, concrete scheme is:
1) drainage chute and plugging structure of connecting well
The upper cover of the drainage chute is covered with chute cover plates 1, and the gaps between the chute cover plates 1 and the drainage chute are filled with the water with the specification of 400g/m2The non-woven geotextile 2 needs to be densely filled in the gap, so that tailings are prevented from entering the drainage chute through the gap, and water leakage and sand leakage are realized; a stone block section 3, a broken stone section 4 and a melon and rice stone section 5 are respectively arranged in the drainage chute from bottom to top, and stone blocks are also filled in the connecting well 8 and are connected with the stone block section 3 in the drainage chute; the length of a blocking section formed by the stone block section 3, the broken stone section 4 and the melon and rice stone section 5 in the drainage chute is 1/3-3/8 of the total length of the drainage chute; arranging an integrated prefabricated top cover plate 6 at a water inlet of the drainage chute, wherein the size of the section of the top cover plate 6 is required to completely wrap the water inlet of the drainage chute; the gap between the water inlet of the drainage chute and the top cover plate 6 is filled with the specification of 400g/m2A non-woven geotextile 2; the particle size of the stone in the stone block section 3 is 5-25 cm, the particle size of the broken stone in the broken stone section 4 is 0.5-2 cm, the particle size of the melon rice stone in the melon rice stone section 5 is 0-0.5 cm, and aggregates (stone block, broken stone and melon rice stone) in each section have a certain gradation, the aggregates poured into the drainage chute each time are few and uniform, and long bamboo pieces are used for poking and tamping to prevent the accumulation phenomenon. In the block structure of drainage chute and connecting well, establish the interior shutoff section length of drainage chute and be L, then: the length of the stone block section 3 is 0.45L, the length of the broken stone section 4 is 0.35L, and the length of the melon and rice stone section 5 is 0.20L.
2) Reverse filtering and draining structure of drainage culvert
A reverse filter body which is 6.5m long and consists of a block stone section 3, a broken stone section 4 and a melon and rice stone section 5 is arranged from the outlet of the drainage culvert to the upstream; in the lump stone section 3, the particle size of the lump stone is 5-25 cm; in the crushed stone section 4, the particle size of the crushed stone0.5-2 cm; in the melon-rice stone section 5, the grain diameter is 0-0.5 cm; a certain amount of chutes for guiding and draining water and water seepage in the culvert are pre-embedded in the culvert and have the specification of 400g/m2The PE seepage drainage pipe 7 is a floral pipe, and the periphery of the PE seepage drainage pipe 7 is wrapped by 2 layers of pipes with the specification of 400g/m2The non-woven geotextile 2 is firmly tied by galvanized iron wires; a closed concrete blocking wall 9 is arranged at the outlet of the drainage culvert, the concrete label of the blocking wall 9 is not less than C30, the foundation is located on the old soil layer and extends into the depth below the ground by 1.5-3 m, the section size of the blocking wall 9 is required to completely wrap the outlet of the drainage culvert, and the anti-filtering body is prevented from being flushed out of the culvert by the gradually increased water pressure along with the time. In the anti-filter and the row of drainage culvert ooze the structure, it is l to establish the total length of the anti-filter body that stone section 3, rubble section 4, melon and rice stone section 5 constitute, then: the length of the stone block section 3 is 0.45 l; the length of the gravel section 4 is 0.35 l; the length of the melon-rice stone section 5 is 0.20 l.
The utility model relates to a shutoff of tailing storehouse flood discharge facility, dredge structure have been used in the old flood discharge system in certain copper mine tailing storehouse and certain iron mine tailing storehouse closed storehouse design respectively, and the shutoff effect is fabulous, and engineering cost is low, has avoided because potential safety hazard and risk that the shutoff of flood discharge system became invalid and bring have received user's high evaluation.