CN104264635A - Construction technology of slag stacking behind concrete faced rock-fill dam - Google Patents

Abstract

The slag stacking construction technology behind the face rockfill dam relates to the technical field of hydropower and water conservancy engineering. It sets the spoil area behind the concrete face rockfill dam, and mainly stacks spoils from the main dam foundation, revetment excavation, stone yard excavation, and temporary engineering excavation. The top and side slopes of the spoil area are greened For soil and water conservation measures, set up horse tracks at appropriate elevations, and set drainage prisms and drainage corridors in the slag body behind the dam to discharge seepage water in the slag body and serve as a drainage channel for the main dam. The slag yard is arranged behind the dam, and the slag pile is directly pressed on the downstream dam surface, which can reduce the land acquisition and resettlement of the slag yard and its connecting roads; it is close to the excavation area of the project, which reduces the slag transportation distance; part of the main dam can be used The drainage and protective measures of the slag yard reduce the protection of the slag yard; the slag pile can be used as the weight of the dam foot, which increases the stability of the dam body, especially the anti-seismic stability; the slag yard structure behind the main dam is economical and environmentally friendly. It can be widely used in the construction of rockfill dams in hydropower and water conservancy projects.

Description

Construction technology of slag pile behind face rockfill dam

technical field

The invention relates to the technical field of hydropower and water conservancy engineering, in particular to the slag stacking construction technology behind a face dam.

Background technique

The main advantages of the construction of face rockfill dams are the full use of local materials, simple construction, reasonable use of excavated materials, reduction of spoils, savings in land occupation and investment, and good environmental protection effects. However, not all excavation slag can be used as dam filling materials. The organic components contained in humus soil are unstable, and the physical and mechanical properties are poor; generally, due to severe weathering, the rock mass above the middle part has low strength and physical and mechanical indicators. If it is broken, it cannot go to the dam and is discarded. These waste materials need to be accommodated in the waste slag area. Generally, some natural valleys are selected as slag dumps in general engineering, which brings a series of problems such as land acquisition and resettlement in the spoil area and its connecting roads, long distance of spoil transportation, water and soil conservation, and environmental protection. High, steep ditches, and large water catchment volumes make the slag field protection work a lot, which is neither economical nor environmentally friendly.

Contents of the invention

The technical problem to be solved by the present invention is: in view of the above problems, through the slag stacking technology behind the face rockfill dam, make full use of the space behind the dam to pile up the slag, provide a land acquisition and resettlement that can reduce the slag area and its connecting roads, Reduce the amount of slag field protection works and waste slag transportation distance, increase the stability of the dam body, beautify the environment of the dam area, and create an economical and environmentally friendly slag field structure behind the dam.

The technical solution of the present invention is: the slag stacking construction technology behind the face rockfill dam, which is to set the spoil area behind the face rockfill dam, and mainly pile up the spoil of the main dam foundation, bank revetment excavation, and stone yard excavation , as well as the spoil excavated by the temporary project, greening and water conservation measures shall be set up on the top and side slope of the spoil area, horse roads shall be set at appropriate elevations, and drainage prisms and drainage corridors shall be set in the slag dump behind the dam to discharge seepage in the slag dump and as a drainage channel for the main dam.

The technical effects of the present invention are: 1. The slag field is arranged behind the dam, and the slag body is directly pressed on the downstream dam surface, which can reduce the land acquisition and resettlement of the slag field and its connecting roads; 2. It is close to the excavation area of the project, reducing 3. The drainage of the main dam and its protection measures can be partially utilized, which reduces the protection amount of the slag field project; 4. The slag body can be used as the weight of the dam foot, which increases the stability of the dam body, especially Seismic and stable; 5. The top surface of the slag yard and the downstream slope are greened to beautify the environment of the dam area, adding recreational facilities such as squares, which is conducive to the development of the tourism industry in the later stage; 6. The structure of the slag yard behind the main dam is economical and environmentally friendly, and can be widely used It is used in the construction of rockfill dams in hydropower and water conservancy projects.

Description of drawings

Fig. 1 is a schematic plan view of the slag field structure behind the main dam of the present invention;

Fig. 2 is a schematic cross-sectional view of the structure of the slag field behind the main dam of the present invention.

Detailed ways

As shown in Figures 1 and 2, the spoil area is set behind the face rockfill dam, and the spoils from the main dam foundation, revetment excavation, stone yard excavation, and temporary engineering excavation are mainly piled up. Greening and water conservation measures shall be provided on the top and side slope of the slag area, horse roads shall be set at appropriate elevations, and drainage prisms and drainage corridors shall be arranged in the slag pile behind the dam to discharge water seepage in the slag pile and serve as a drainage channel for the main dam, which can prevent During the construction period, the reverse water pressure is generated behind the panel, and the drainage of the dam body can be kept smooth during the operation period.

Drainage prisms are arranged in the slag body behind the dam, and the drainage prisms on both sides are arranged in the slag body near the bank slope, mainly to discharge the seepage water in the high parts of the dam body and the slag body; the main drainage prisms are arranged between the bottom of the slag body, and the main Drainage corridors are set in the drainage prism, which are the main drainage channels for the main dam and slag, which can not only prevent reverse water pressure behind the panel during the construction period, but also maintain smooth drainage of the dam during the operation period.

Three drainage stainless steel pipes are installed on the panel, which extend into the drainage corridor, and a system cut-off drainage ditch is set behind the dam (including around the slag pile) to discharge the rainstorm catchment water from the mountains on both sides and the surface of the dam body.

The spoil area is set behind the concrete face rockfill dam, mainly stacking spoils from the excavation of the main dam foundation, revetment excavation, stone yard, and temporary works. , and set up horse trails at appropriate elevations. Drainage prisms and drainage corridors are set in the slag body behind the dam to discharge water seepage in the slag body and serve as a drainage channel for the main dam, which can prevent reverse water pressure behind the face plate during the construction period and maintain the dam during the operation period. Body drainage is smooth.

The spoil area behind the dam is located outside the dam body of the concrete face rockfill dam and within the scope of land acquisition behind the dam. It is mainly piled with excavated spoil from the excavation of the main dam foundation and revetment, the excavation of the stone yard, and temporary works. The top of the spoil area is Greening and water conservation measures shall be set up on the side slope.

A drainage prism is arranged in the slag pile behind the dam. Drainage prisms on both sides are set in the slag body near the bank slope, and mainly drain water seepage from the dam body and slag body at the height; main drainage and prisms are set between the bottom of the slag body, and drainage corridors are set in the main drainage prism for The main drainage channel of the main dam and the slag body can not only prevent the reverse water pressure behind the face plate during the construction period, but also keep the drainage of the dam body smooth during the operation period. Three drainage stainless steel pipes are installed on the panel, which extend into the drainage corridor, and a system cut-off drainage ditch is set behind the dam (including around the slag pile) to discharge the rainstorm catchment water from the mountains on both sides and the surface of the dam body.

Implementation example 1:

Below take the large-scale project that has adopted the technical scheme of the present invention as example in conjunction with accompanying drawing to further illustrate: the main dam of the upper reservoir of the Mudanjiang pumped storage power station, the spoil area behind the dam is located within the range line of land expropriation behind the main dam of the upper reservoir, and the main dam On the rear bank slope, within the excavation line of the main dam foundation of the upper reservoir. The main spoil area is located behind the concrete face rockfill dam, where the main dam foundation and revetment excavation, the spoil from the excavation of the stone yard and the excavation spoil of temporary works are mainly piled up. The spoil volume is about 264×10 ⁴ m ³ , The elevation of the top platform in the spoil area is 640.00m, the top width is 112m, and the downstream side-slope ratio is 1:3.0. Greening and water conservation measures (three-dimensional plant nets, internal shrubs and grass species) are set up. The maximum height is about 62m. 3m wide bridleways are set at the elevation of 620m.

There are three drainage prisms in the slag pile behind the dam. The foundation of the drainage prism on both sides is on the top of the soil-like fully weathered layer. The cross-section of the drainage prism: the bottom width is 3m, and the thickness is 3m. 5m, and the main drainage channel of the main dam is provided with a drainage corridor. The drainage corridor is reinforced concrete with a gate hole type, the inner diameter is 2m×2.5m (width×height), and the wall thickness is 1.0m. Drainage holes (row spacing 2m, spacing 3m, hole depth 1.5m), the entire tunnel line pre-buried φ100mmPE drainage pipes, spacing 0.5m, row spacing 1.0m; reverse osmosis drainage steel pipes (3φ25cm, leading into the drainage corridor) are installed behind the panel, which can prevent construction The reverse water pressure will be generated behind the panel during the period, and the drainage of the dam body will be kept smooth during the operation period. Behind the dam (including the surrounding area of the slag pile) a system intercepting drainage ditch is set up to discharge the rainwater catchment from the mountains on both sides and the surface of the dam body.

By adopting the technical solution of the present invention, the following effects are obtained:

(1) The project site is located in the forest farm of Chaihe Forestry Bureau in Weihushan ^Forest Park. The slag dump is arranged behind the face rockfill dam. It can reduce the area of arable land and forest land occupied by a large number of slag yards and their connecting roads, and reduce immigration;

(2) The drainage of the rockfill dam and its protection measures can be partially utilized, reducing the protection measures for the slag yard and the protection amount of the slag yard;

(3) It is close to the excavation area of rockfill dams and other projects, which reduces the distance of waste slag transportation and saves a lot of investment;

(4) The slag body can be used as the weight of the dam foot, which increases the stability of the dam body;

(5) The greening of the top surface of the slag yard and the downstream slope surface beautifies the environment of the dam area;

(6) Save nearly ten million in land acquisition fees, engineering measures fees and waste slag transportation costs for slag yards, which is both economical and environmentally friendly.

Claims (3)

1. slag construction technology behind rock dam, it is characterized in that, it is after waste region is located at rock, the waste of the main stacking key dam dam foundation, shore protection excavation, building stones field excavation, and the waste of temporary works excavation, top, waste region and side slope establish greening soil erosion management, and suitable elevation establishes packway, drainage prism and collector drain is established in slag body, in order to discharge the infiltration in slag body and the drainage channel as key dam behind dam.

2. slag construction technology behind rock dam as claimed in claim 1, it is characterized in that, establish drainage prism behind dam in slag body, both sides drainage prism is located at and closes in the slag body of bank slope, establish main drainage prism between bottom slag body, in main drainage prism, establish collector drain.

3. slag construction technology behind rock dam as claimed in claim 1, it is characterized in that, draining stainless steel tube established by panel, stretches into collector drain, arranges system drain dyke behind dam.