CN111945654B

CN111945654B - Structure of predetermineeing of early processing of dammed lake

Info

Publication number: CN111945654B
Application number: CN202010753264.XA
Authority: CN
Inventors: 金浩博; 王东; 刘后露; 郭广鑫; 梁勤正
Original assignee: Sichuan University
Current assignee: Sichuan University
Priority date: 2020-07-30
Filing date: 2020-07-30
Publication date: 2022-04-12
Anticipated expiration: 2040-07-30
Also published as: CN111945654A

Abstract

The invention belongs to the technical field of hydraulic engineering, and particularly relates to a preset structure for early treatment of a barrier lake of a potential landslide or debris flow risk river reach. The preset structure is a plurality of parallel floral tubes arranged on the riverbed of the risk river reach an upstream end water inlet structure connected with the floral tubes. The invention utilizes the principle of the osmotic destruction of the bulk heap of the weir plug: the preset floral tube is embedded by the barrier body, and an automatic drainage channel and a permeation damage channel are formed along with the rising of the water level of the barrier lake, so that the aims of preventing the rising of the water level of the barrier lake and generating permeation damage at the periphery of the floral tube to gradually drain the loose deposits of the barrier body downstream and finally automatically removing the barrier body by means of water power are fulfilled. The method has the advantages that the disposal cost of the barrier lake is low, and the risk of the barrier lake and the property and life loss caused by water drainage are reduced to the maximum extent.

Description

Structure of predetermineeing of early processing of dammed lake

Technical Field

The invention belongs to the technical field of hydraulic engineering, and particularly relates to a preset structure for early treatment of a barrier lake of a river section with potential landslide or debris flow risk.

Background

The dammed lake is formed by blocking off a river valley or storing water on a river bed by a landslide caused by landslide or landslide caused by an earthquake. China, particularly in western regions, has complex terrain and geology and is in an active earthquake activity zone, and the barrier lake has high risk probability, so that the downstream safety is endangered. The damming body of the damming lake is not fixed and unchanged, if no manual intervention exists, the damming body rises along with the water level of the damming lake and is washed, eroded, dissolved, collapsed and the like, if the damming lake breaks the mouth, a flood peak can be formed in a downstream river channel, and the destructive power of the damming lake far exceeds the flood disaster generated by general rainstorm. For barrier lakes with high risk, no rapid and low-risk rescue method is available at present. Traditionally, manual excavation, blasting and other modes are adopted to conduct weir crest drainage, and disposal is conducted by a method of gradually enabling a weir body to self-burst, but the process always corresponds to the reality that the water level of a dammed lake rises, the water storage amount is greatly increased, and the risk is increased, so that a small tiger grows into a large tiger, and even if final successful disposal is conducted, downstream flood disasters caused by burst weir flood and the cost are quite staggering.

In the prior art, the invention discloses a method for reducing the water level of a dammed lake by adopting a siphon effect, and using water flow induced by siphon to scour a downstream damming body to play roles in reducing the water level and removing the damming body by hydraulic erosion.

Disclosure of Invention

The invention aims to: in order to overcome the defects that the conventional method for disposing the weir dam needs to consume a large amount of manpower, material resources and financial resources and the risk of flood for the weir dam is high, the invention provides the preset structure for disposing the weir dam lake in the early stage, and the aims of inhibiting the water level of the weir dam lake from rising or rising too fast and gradually eroding and removing the weir dam body in an osmotic destruction mode are fulfilled by artificially manufacturing the drainage channel and the osmotic destruction channel by utilizing the osmotic destruction principle of the loose earth-rock structure.

In order to achieve the above object, according to an embodiment of the present invention, a preset structure for early disposal of a barrier lake is provided, where the preset structure for early disposal of a barrier lake comprises an upstream water inlet, a preset floral tube junction section, and a control gate. The upstream water inlet is connected with the intersection section of the preset perforated pipe and then connected with the preset perforated pipe which is arranged in parallel, and a control gate is arranged at the upstream water inlet.

The pipe body of the preset perforated pipe is provided with water outlet holes which are arranged at intervals in a quincunx shape.

The preset flower tubes are uniformly arranged at intervals at the bottom of the riverbed parallel to the river bank, the number of pipelines is arranged according to the width of the river, and the diameter of the pipeline is adjusted according to the depth and the amount of water.

The length of the preset floral tube is determined according to the length of a risk valley where the riverbed is located; the upstream water inlet is arranged at a certain interval distance upstream of the risk valley, and the tail part of the preset floral tube is arranged at a certain interval distance downstream of the risk valley; the separation distance is determined according to the risk level of the river valley.

The arrangement position of the preset perforated pipe intersection section is as close to the water inlet as possible, and the part adopts a pipeline without a water outlet hole.

And a control gate is arranged at the upstream water inlet. When disasters such as debris flow do not occur, the valve is closed, and the preset structure does not act and influence the normal state of the original riverbed; when a disaster happens to form a barrier lake, the valve is opened to enable the preset structure to start working, and the seepage channel acts.

The design principle of the invention is as follows: by presetting floral tubes at the bottom of a riverbed for predicting or monitoring a risk river reach, when a barrier lake is formed due to a risk disaster, a barrier body buries a preset floral tube main body, at the moment, an upstream water inlet control gate is rapidly opened, water flows enter a preset structure under the action of an upstream water head and are flushed out of the preset floral tubes and water outlet holes of the preset floral tubes, loose deposits of the barrier body on the periphery of a tube body are flushed and osmotically damaged while the upstream water level is inhibited from rising, the loose deposits are continuously flushed and carried away by the water flows downstream, and the barrier lake is thoroughly cleared up until the barrier body gradually collapses, erodes, osmotically breaks and flushes. Although the process is possibly longer, the state that the small tiger is not grown up and does not generate power is always maintained, and the hydraulic power is used for avoiding one-sidedly and one-sidedly drawing, so that the risk is low and the cost is low.

Compared with the existing method for removing the weir plug, the method has the advantages that:

(1) the hidden danger of the dammed lake is eliminated without large-scale mechanical excavation, the danger of dam break caused by blasting is avoided, the drainage and permeation channels are formed by the aid of the preset flower tubes, and the damming body is flushed by the aid of the flushing effect of water flow, so that a large number of resources can be saved.

(2) The method is simple to operate, high in operability and low in engineering cost, and can continuously guarantee the safety of the downstream area of the risk valley by predicting or monitoring the arrangement before the disaster happens.

(3) The invention can respond quickly when a disaster happens, and effect can be generated in time, so that the water level and the water quantity of the barrier lake are controlled at the early stage, the danger is low, large-flow flood cannot be generated during the discharge, and the invention has no harm to downstream areas.

Drawings

Fig. 1 is a top view of the structural arrangement of the present invention.

Fig. 2 is a cross-sectional view of the structural arrangement of the present invention.

FIG. 3 is a schematic view of the outlet holes on the preset flower tubes.

FIG. 4 is a cross-sectional view of a pre-set floral tube.

FIG. 5 is a cross-sectional view of an upstream water inlet.

1-upstream water inlet; 2, presetting a floral tube; 3-water outlet; 4-presetting a floral tube intersection section; 5-Risk valley; 6-control gate.

Detailed Description

The invention discloses a preset structure for early treatment of a barrier lake, which comprises an upstream water inlet, a preset floral tube intersection section and a control gate. The upstream water inlet is connected with the intersection section of the preset perforated pipe and then connected with the preset perforated pipe which is arranged in parallel, and a control gate is arranged at the upstream water inlet.

Presetting flower tubes which are uniformly arranged at intervals of 20-30 m at the bottom of a riverbed in parallel, wherein the arrangement number is determined according to the characteristics of a river valley; the diameter of the pipeline is selected according to hydrological characteristics such as the water level and the water quantity of a river channel; the pipe body of the preset perforated pipe is provided with quincunx water outlet holes which are arranged at intervals.

The length of the preset flower tube is determined according to the length of a risk river valley where the river bed is located; the upstream water inlet is arranged at a certain interval distance upstream of the risk valley, and the tail part of the preset floral tube is arranged at a certain interval distance downstream of the risk valley; the separation distance is determined according to the risk level of the river valley.

The preset perforated pipe is connected with the upstream water inlet through a preset perforated pipe intersection section, and the work of the preset structure is controlled through a control gate. The arrangement position of the preset perforated pipe intersection section is as close as possible to the water inlet, and the part adopts a pipeline without a water outlet hole.

The upstream water inlet is provided with a control gate and a valve. When disasters such as debris flow do not occur, the valve is closed, and the preset structure does not act and influence the normal state of the original riverbed; when a barrier lake is formed in the occurrence of a disaster, the valve is opened to enable the preset structure to start working, and the seepage channel acts; when the preset structure is in a standby stage, silt possibly enters the preset perforated pipe, and the control gate is opened periodically to wash away the silt in the pipe by using water flow.

The upstream water inlet, the type of the control gate, the size of the preset pipeline and the like are changed according to different types and risk grades of the risk river valley.

Claims

1. A preset structure for early treatment of a barrier lake is characterized by comprising an upstream water inlet (1) and a preset floral tube (2) horizontally laid at the bottom of a riverbed; the upstream water inlet (1) is provided with a control gate (6) to open and close the structure, and is connected with the preset perforated pipe (2) through a preset perforated pipe intersection section (4); presetting a floral tube (2), wherein a tube body of the floral tube is provided with quincunx water outlet holes (3) which are distributed at intervals, the diameter of a pipeline is determined according to the water depth and the water volume, the larger the water depth and the water volume is, the larger the diameter of the pipeline is, the number of pipelines is determined according to the width of a river width and the uniform interval parallel distribution, and the length of the pipeline is determined according to the length of a risk river valley (5) where the river bed is located; the upstream water inlet (1) is arranged at a certain interval distance on the upstream of the risk valley (5), the tail of the preset flower tube (2) is arranged at a certain interval distance on the downstream of the risk valley (5), and the interval distance is determined according to the risk grade of the valley.