CN107687159A - The combination dam type and its method of construction of a kind of arch dam gravity dam - Google Patents

Abstract

The invention provides a combination dam type of arch dam-gravity dam and its construction method. The composite dam type includes an arch dam section, a concrete rockfill gravity dam section, and a concrete gravity dam section connecting the arch dam section and the concrete rockfill gravity dam section. One end of the arch dam section is supported on the bank slope bedrock, and the other end is supported on the concrete gravity dam section. The concrete rockfill gravity dam section includes a concrete gravity dam on the upstream side and a rockfill body on the downstream side. The construction method of the composite dam type includes the steps of interception and diversion construction, dam foundation groove excavation construction, concrete gravity dam section construction, concrete rockfill gravity dam section construction and arch dam section construction. The composite dam type expands the applicable conditions of the arch dam, the applicability of the dam type is wider, the structural design is simple, the construction is convenient, and it reflects good environmental protection.

Description

Combination dam type of arch dam-gravity dam and construction method thereof

technical field

The invention relates to the field of hydraulic structure engineering in hydraulic engineering, in particular to a novel dam type combined with an arch dam and a gravity dam and a construction method thereof.

Background technique

An arch dam is a water retaining dam built in a canyon. It is made into a horizontal arch, with the convex side facing the upstream, and the two ends are close to the canyon wall. It is a water-retaining building that can transmit part of the horizontal load to the bedrock on both sides. Space shell structure. Compared with the gravity dam, the stability of the arch dam body under the action of water pressure does not need to rely on its own weight to maintain, the arch dam has less requirements on the rock foundation of the dam site, and the arch dam mainly uses the reaction of the arch end bedrock to support. The section of the arch ring mainly bears the axial reaction force, which can make full use of the strength of the dam building material. Therefore, it is a dam type with good economy and safety. The terrain conditions suitable for the construction of arch dams are "V" or "U"-shaped terrain with narrow valleys, bilateral symmetry, and shrinking downstream, and the ratio of the valley width L to the dam height H (that is, the aspect ratio) is less than 4.5. The geological conditions are that the bedrock is uniform, solid and complete, has sufficient strength, low water permeability and can resist weathering.

It can be seen that although the arch dam is a dam type with good economy and safety, due to its high requirements on topographical and geological conditions, there are not many cases where the arch dam is suitable for construction. In terms of terrain conditions, it is common to see asymmetric river valleys with steep slopes on one side and gentle slopes on the other side, which are not suitable for the construction of arch dams. In terms of geological conditions, it is common to see complete, uniform, high-strength rock mass and weak water permeability on one side of the bank slope, while the rock mass on the other side bank slope is of poor quality, which is not suitable for building an arch dam.

Compared with arch dams, gravity dams rely on their own weight to maintain a stable dam type, and are highly adaptable to different terrain and geological conditions. Gravity dams can be built in any shape of valley, but the gravity dam has a large volume.

For river valleys where the slope topography and geological conditions on one side meet the construction requirements of an arch dam, while the other side does not meet the construction requirements of an arch dam but meets the construction requirements of a gravity dam, it is impossible to realize the construction of an arch dam alone as a barrage dam. It is not necessarily economical to choose a gravity dam.

Contents of the invention

The object of the present invention is to provide a combination dam type of arch dam-gravity dam and its construction method, so as to solve the problems in the prior art.

The technical scheme adopted for realizing the object of the present invention is such that a composite dam type of an arch dam-gravity dam comprises an arch dam section and a concrete rockfill gravity dam section, and a connecting arch dam section and a concrete rockfill gravity dam section concrete gravity dam section.

The arch dam section is in the shape of an arch convex to the upstream on a plane. One end of the arch dam section is supported on the bank slope bedrock, and the other end is supported on the concrete gravity dam section.

The concrete rockfill gravity dam section includes a concrete gravity dam on the upstream side and a rockfill body on the downstream side.

The contact surface between the concrete gravity dam section and the concrete rockfill gravity dam section is provided with structural joints. The structural seams are filled with water-stopping materials.

The present invention also provides a kind of construction method about the combination dam type of above-mentioned arch dam-gravity dam, comprises the following steps:

1) According to the designed diversion and closure scheme, construct the diversion facilities and closure facilities in the dam site area, and intercept and divert the surface and groundwater flow of the valley.

2) Excavate the dam type dam foundation according to the designed dam foundation groove position and geometric dimensions and other parameters.

3) Construct the concrete gravity dam section according to the designed dam structure.

4) Construct the concrete rockfill gravity dam section according to the designed dam structure.

5) Construct the arch dam section according to the designed dam structure.

Technical effect of the present invention is beyond doubt:

A. One end of the arch dam section is supported on the concrete gravity dam section, which solves the problem that the valley side does not meet the construction requirements of the arch dam, expands the applicable conditions of the arch dam, and the applicability of the dam type is more extensive;

B. The design is simple, the construction is convenient, and it reflects good environmental protection;

C. The dam type has strong reliability, and the structure meets the deformation, strength and stability requirements;

D. The dam type is small in size and the amount of concrete is small, which saves engineering investment and has good economy.

Description of drawings

Figure 1 is a schematic diagram of a composite dam structure;

Fig. 2 is A-A sectional view;

Figure 3 is a cross-sectional view of the crown of the arch dam section;

Fig. 4 is a structural schematic diagram of a concrete gravity dam section;

Figure 5 is a schematic diagram of the structure of the concrete rockfill gravity dam section.

In the figure: arch dam section 1, concrete gravity dam section 2, concrete rockfill gravity dam section 3, concrete gravity dam 301, and rockfill body 302 on the downstream side.

detailed description

The present invention will be further described below in conjunction with the examples, but it should not be understood that the scope of the subject of the present invention is limited to the following examples. Without departing from the above-mentioned technical ideas of the present invention, various replacements and changes made according to common technical knowledge and conventional means in this field shall be included in the protection scope of the present invention.

Example 1:

This embodiment discloses a composite dam type of an arch dam-gravity dam. In this embodiment, due to the limitation of slope topography and geological conditions, it is not suitable to build an arch dam. After comprehensive consideration of safety and economy, a composite dam type is selected.

Referring to Fig. 1 and Fig. 2, the combined arch dam-gravity dam type includes arch dam section 1, concrete rockfill gravity dam section 3, and concrete gravity dam section 2 connecting arch dam section 1 and concrete rockfill gravity dam section 3 .

The arch dam section 1 is located on the side of the valley bank slope with steep topography and good geological conditions. The arch dam section 1 is in the shape of an arch convex to the upstream on a plane. One end of the arch dam section 1 is supported on the steep bank slope bedrock, and the other end is supported on the concrete gravity dam section 2 . Referring to Fig. 3, the vertical section of the arch dam section 1 is in the form of a cantilever beam.

Referring to Fig. 4, the concrete rockfill gravity dam section 3 is located on the side of the valley bank slope with gentle topography or poor geological conditions (that is, the conditions for arch dam construction are not met). One end of the concrete rockfill gravity dam section 3 is close to the bank slope, and the other end is close to the concrete gravity dam section 2 . The concrete rockfill gravity dam section 3 includes a concrete gravity dam 301 on the upstream side and a rockfill body 302 on the downstream side. The basic section of the concrete gravity dam 301 is a right triangle as a whole. The upstream side of the concrete gravity dam 301 is a vertical plane, and the downstream side is an inclined plane.

Referring to FIG. 5 , the concrete gravity dam section 2 is mainly used to bear the end load of the arch dam section 1 and limit the deformation of the end of the arch dam section 1 . The basic section of the concrete gravity dam section 2 is a right triangle as a whole. The upstream side of the concrete gravity dam section 2 is a vertical plane, and the downstream side is an inclined plane. The concrete gravity dam section 2 is at the junction with the arch dam section 1 and the concrete rockfill gravity dam section 3 . The slope on the downstream side of the concrete gravity dam section 2 is flush with the slope on the downstream side of the rockfill body 302 . The crest elevation of the concrete gravity dam section 2 is equal to the crest elevation of the arch dam section 1 or the concrete rockfill gravity dam section 3 . The contact surface between the concrete gravity dam section 2 and the concrete rockfill gravity dam section 3 is provided with structural joints. The structural seams are filled with water-stopping materials.

Example 2:

This embodiment discloses a construction method of the composite dam type of the arch dam-gravity dam described in Embodiment 1, comprising the following steps:

1) According to the designed diversion and closure scheme, construct the diversion facilities and closure facilities in the dam site area, and intercept and divert the surface and groundwater flow of the valley.

2) Excavate the dam type dam foundation according to the designed dam foundation groove position and geometric dimensions and other parameters. Specifically, it includes steps such as strengthening the slope, excavating the abutment trench of the bank slope, and excavating the foundation trench of the valley dam foundation.

3) Construct the concrete gravity dam section 2 according to the designed dam structure.

4) Construct the concrete rockfill gravity dam section 3 according to the designed dam structure.

5) Construction of arch dam section 1 according to the designed dam body structure.

Claims (2)

1. A kind of 1. combination dam type of arch dam-gravity dam, it is characterised in that：Including arch dam section (1) and concrete enrockment gravity monolith (3), and linking arch dam section (1) and concrete enrockment gravity monolith (3) concrete gravity monolith (2)；

   The arch dam section (1) is in the plane in the arch for being convex to upstream；Described arch dam section (1) one end is supported on bank slope basement rock, The other end is supported on concrete gravity monolith (2)；

   The concrete enrockment gravity monolith (3) includes the concrete gravity dam (301) of upstream side and the rockfill in downstream (302)；

   The concrete gravity monolith (2) and the contact surface of concrete enrockment gravity monolith (3) are provided with structural joint；The structure Sealing material is filled with seam.
2. 2. the method for construction of the combination dam type on arch dam-gravity dam described in claim 1, it is characterised in that including following step Suddenly：

   1) water conservancy diversion according to design, scheme of river closure, the parallel works for Dam Site of constructing and dam facility, and to river valley earth's surface, Lower current are dammed and water conservancy diversion；

   2) according to parameters such as the dam foundation foundation trench position of design and physical dimensions, the dam type dam foundation is excavated；

   3) the dam structure construction concrete gravity monolith (2) according to design；

   4) the dam structure construction concrete enrockment gravity monolith (3) according to design；

   5) the dam structure construction arch dam section (1) according to design.