A secondary anti-sand accumulation facility based on windbreak wall

Abstract

The invention relates to the technical field of wind and sand prevention for transportation facilities, and in particular to a secondary anti-sand accumulation facility based on a windbreak wall, comprising a first windbreak wall arranged on an embankment, flat land or a road cut, a second retaining wall arranged on the leeward side of the first windbreak wall of the embankment, flat land or road cut, and a sand interception ditch dug on the leeward side of the second retaining wall, and at the same time, an inclined plate is added on the top of the first windbreak wall for the road cut type with the most serious sand accumulation; by adopting the measures of arranging the second retaining wall, the sand interception ditch and the inclined plate, the phenomenon of sand on the leeward side returning to the line under the action of eddy current and forming sand accumulation is effectively prevented, thereby ensuring that the train is not affected by strong winds and sand accumulation in different terrains and runs at high speed and safely.

Description

Technical Field

[0001] The invention relates to the technical field of wind and sand prevention for transportation facilities, and in particular to a secondary anti-sand accumulation facility based on a windbreak wall. Background Art

[0002] Lanzhou-Xinjiang Second Line is the world's first high-speed railway that passes through a strong wind zone. It passes through the Yandun wind zone, Baili wind zone, Sanshili wind zone and Dabancheng wind zone, with a total railway mileage of 462.4 kilometers in the wind zone section. Strong winds frequently occur in the four major wind zones with extremely high wind speeds. In some sections, there are 208 days of strong winds greater than level 8 per year. Strong winds can easily cause accidents such as overturned trains, vehicle runaways, broken windows, and damaged driving facilities, which can cause great harm to railway operations, maintenance and transportation safety. In order to resist the harm of strong winds to passing trains, a large number of windproof structures have been built along the Lanzhou-Xinjiang Second Line. The most widely used of these are windbreak walls, such as Figure 4 , Figure 5 and Figure 6 As shown in the figure, the sections with windbreaks account for 65.1% of the total length of the Xinjiang section. Some windy sections are located in the undulating Gobi Desert, and the line passes through these places to form many road cuts, embankments and flat land. In the embankments and flat land sections, the height of the windbreaks is set at 3.8-4.3m to ensure that the train does not overturn when running in a windy environment. The road cuts themselves have a certain windproof ability, and the height of their windbreaks is smaller than that of the embankments and flat land sections at the beginning of the design.

[0003] Since the high-wind area is located in the Gobi Desert, the climate is dry and rainless, the soil is relatively loose, and the surface particle resources are rich. Under the action of strong airflow, the Gobi surface is seriously unstable, and the sand particles are easily driven by the wind to form strong wind and sand flow. Therefore, the high-wind area is usually also an area with frequent sand and dust activities. When the sand-carrying airflow passes through the windbreak wall along the railway, the airflow velocity is redistributed, and the balance state of the wind and sand flow is destroyed, causing some sand particles to be deposited around the windbreak wall and on the railway track, seriously affecting the safe operation of the train. Existing research results show that the line sand accumulation formed by the windbreak wall is mainly due to the large eddy area on the leeward side. The sand particles passing through the top of the windbreak wall are returned to the line under the action of the eddy current and form sand accumulation. Summary of the invention

[0004] In response to the problems existing in the prior art, the present invention provides a secondary anti-sand accumulation facility based on a windbreak wall. By adopting a second windbreak wall and a sand interception ditch, it effectively prevents the sand on the leeward side from returning to the line under the action of eddy currents and forming sand accumulation, ensuring that the train is not affected by strong winds and sand accumulation in different terrains, and can run at high speed and safely.

[0005] To achieve the above purpose, the technical solution adopted in this application is as follows:

[0006] A secondary anti-sand accumulation facility based on a windbreak wall comprises a first windbreak wall 1 arranged on an embankment, flat land or road cut, a second windbreak wall 2 arranged on the leeward side of the first windbreak wall 1 of the embankment, flat land or road cut, and a sand interception ditch 3 dug on the leeward side behind the second windbreak wall.

[0007] The height of the second windshield wall is the same as that of the first windshield wall 2 .

[0008] The second retaining wall 2 on the embankment is arranged at the top of the slope on the leeward side 1 of the first windbreak wall, the second retaining wall 2 on the flat ground is arranged 15-17m from the leeward side of the first windbreak wall 1, and the second retaining wall 2 on the cutting is arranged at the top of the slope on the leeward side of the first windbreak wall 1;

[0009] The sand intercepting ditch 3 is in an inverted trapezoidal shape, and the slope of the hypotenuse is 1.5:1.

[0010] The sand interception ditch 3 on the embankment is set at 1.5-2.5m away from the foot of the slope on the leeward side of the second retaining wall 2; the sand interception ditch 3 on the flat land or road cutting is set at 1.5-2.5m away from the leeward side of the second retaining wall 2.

[0011] An inclined plate 4 is installed on the first windbreak wall 1 arranged on the road cutting.

[0012] The angle between the leeward side of the first windbreak wall 1 and the inclined plate 4 is 120° to 150°.

[0013] The beneficial effects of the present invention are:

[0014] 1) It can ensure both sand and wind protection, getting rid of the shortcoming that the original windbreak wall cannot protect against wind and sand at the same time.

[0015] 2) The structure of the existing windbreak wall will not be changed, and the balance of wind and sand protection for embankments, cuttings and flat areas can be ensured.

[0016] 3) Quick installation, simple construction, low cost, and can be widely used. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] Figure 1 This is a schematic diagram of the embankment type windbreak wall structure of the present invention;

[0018] Figure 2 This is a schematic diagram of the flat-ground windbreak wall structure of the present invention;

[0019] Figure 3 This is a schematic diagram of the structure of the cutting type windbreak wall of the present invention;

[0020] Figure 4 It is a schematic diagram of the embankment type windbreak wall structure in the background technology;

[0021] Figure 5It is a schematic diagram of the flat-ground windbreak wall structure in the background technology;

[0022] Figure 6 It is a schematic diagram of the structure of a road cutting type windbreak wall in the background technology;

[0023] As shown in the figure: the first windbreak wall 1, the second windbreak wall 2, the sand interception ditch 3, and the inclined plate 4. DETAILED DESCRIPTION

[0024] The technical solution of the present invention is further described below with reference to the accompanying drawings and through specific embodiments:

[0025] Example 1

[0026] The present invention is a secondary anti-sand accumulation facility based on the existing windbreak wall, i.e., the first windbreak wall 1, including the first windbreak wall 1, the second windbreak wall 2, and the sand interception ditch 3. In addition to the first windbreak wall 1, the second windbreak wall 2 and the sand interception ditch 3, a sloping plate 4 with a certain angle is also added to the top of the first windbreak wall 1 for the road cut type, so as to shift the range of the leeward side reflow zone, so that the reflowing wind and sand flow can be intercepted by the second windbreak wall 2. However, the sloping plate 4 cannot be set for the embankment and flat land type, because the sloping plate 4 will affect the contact network and power supply facilities.

[0027] Figure 1 It is a secondary anti-sand facility for the embankment-type windbreak wall. Figure 4 It is a traditional embankment-type windbreak structure, with a height of generally 3.8-4.3m. Its original design function was to block the wind, and it did not take into account the accumulation of sand on the line. However, the line is now seriously sandy, affecting the safe operation of high-speed trains. Existing research results show that the reason for sand accumulation is that when the wind and sand flow passes through the first windbreak 1, the air flow velocity is redistributed, the balance state of the wind and sand flow is destroyed, and a large recirculation area is formed behind it, causing some sand particles that pass over the windbreak to return to the line under the action of the recirculation area and form sand accumulation. Figure 1 The middle line II indicates that the sand-carrying airflow returns to the line under the action of the recirculation zone, and line I indicates that the sand outside the recirculation zone moves to a distant place with the wind. Figure 1 The second retaining wall 2 and the sand intercepting ditch 3 are newly added. The function of the second retaining wall 2 is to intercept the return sand-carrying airflow and deposit it at a location far away from the track line. The function of the sand intercepting ditch 3 is to prevent the formation of new sand sources behind the second retaining wall 2, because sand deposition will gradually accumulate over time.

[0028] Figure 2 It is a secondary anti-sand accumulation facility of a flat-ground windbreak wall. Its sand accumulation mechanism is the same as that of an embankment-type windbreak wall, and the working principles of the added second retaining wall 2 and the sand intercepting ditch 3 are also the same.

[0029] Figure 3It is a secondary anti-accumulation facility for the cutting windbreak wall. The reasons for sand accumulation in the traditional cutting windbreak wall are the same as those in the embankment type, but on-site investigations have found that the sand accumulation caused by the cutting windbreak wall is more serious than that of the embankment type and the flat-ground type. The reason is that the cutting itself has a certain windproof function, so the height of the first windbreak wall 1 is shorter than that of the embankment type and the flat-ground type. The specific height is set according to the depth of the cutting, generally within 2.0-2.5m, and some deeper cutting sections do not have windbreak walls. At the beginning of the design, only how to prevent wind was considered, and it was not considered that windy areas are often also areas with rich sand sources, which will cause serious sand accumulation on the line while preventing wind. Therefore, due to the above reasons, the sand accumulation phenomenon in the cutting is more serious. In this regard, in addition to adding the second retaining wall 2 and the sand intercepting ditch 3, the road cutting windbreak wall also adds an inclined plate 4. The reason for adding the inclined plate 4 is that the first windbreak wall 1 of the road cutting is about 8.5m away from the first track line, and the fluid section behind it is large. The recirculation zone formed by the first windbreak wall 1 is often on the track line. After adding the inclined plate 4, the original recirculation zone is moved backward and intercepted by the second retaining wall 2 to achieve the purpose of reducing the accumulation of sand on the line, and the inclined plate 4 will not affect the contact network and other power supply equipment above the track. The role of the sand intercepting ditch 3 is the same as that of the above-mentioned flat land type and embankment type.

[0030] However, embankment-type and flat-ground windbreak walls are not suitable for setting up inclined plates. The reasons are as follows: on the one hand, the distance between the flat-ground and embankment-type windbreak walls and the track line is relatively close, about 4.5m, and the recirculation zone formed on the leeward side is not on the track line; on the other hand, the addition of the inclined plate 4 will affect the contact network and other power supply equipment above the track.

[0031] The results of the wind tunnel test show that after adding the second retaining wall 4, the sand accumulation on the track line is reduced by 63% as a whole (wind speed 21m / s). Therefore, adding the second retaining wall 2 can effectively reduce the sand accumulation on the track.

[0032] Its advantage is that it does not change the structure of the original windbreak wall, and it can protect against wind and sand at the same time. It can also ensure the balance of wind and sand protection for embankments, cuttings and flat areas. It is quick to install, easy to construct, and low in cost, and can be widely used.

[0033] It will be apparent to those skilled in the art that the invention is not limited to the details of the exemplary embodiments described above and that the invention can be implemented in other specific forms without departing from the spirit or essential features of the invention. Therefore, the embodiments should be considered exemplary and non-limiting in all respects, and the scope of the invention is defined by the appended claims rather than the foregoing description, and it is intended that all variations falling within the meaning and scope of the equivalent elements of the claims be included in the invention. Any reference numeral in a claim should not be considered as limiting the claim to which it relates.

[0034] In addition, it should be understood that although the present specification is described according to implementation modes, not every implementation mode contains only one independent technical solution. This description of the specification is only for the sake of clarity. Those skilled in the art should regard the specification as a whole. The technical solutions in each embodiment may also be appropriately combined to form other implementation modes that can be understood by those skilled in the art.

Claims

1. An application of a secondary anti-sand accumulation facility based on a windbreak wall, comprising a first windbreak wall arranged on an embankment, flat land or a road cut, characterized in that: A second retaining wall is set up on the leeward side of the first windbreak wall of the embankment, flat land or cutting, and a sand interception ditch is dug on the leeward side of the second retaining wall so that the railway line is placed between the first windbreak wall and the second retaining wall; The second retaining wall is set at the same height as the first windbreak wall; The second retaining wall on the embankment is set at the top of the slope on the leeward side of the first windbreak wall, the second retaining wall on flat ground is set 15-17m from the leeward side of the first windbreak wall, and the second retaining wall on the cutting is set at the top of the slope on the leeward side of the first windbreak wall.

2. The application of a secondary anti-sand accumulation facility based on a windbreak wall according to claim 1 is characterized in that: The sand intercepting ditch is in the shape of an inverted trapezoid, and the slope of the hypotenuse is 1.5:

1.

3. The application of a secondary anti-sand accumulation facility based on a windbreak wall according to claim 2 is characterized in that: The sand interception ditch on the embankment is set at 1.5-2.5m away from the foot of the slope on the leeward side of the second retaining wall; the sand interception ditch on the flat land or the road cut is set at 1.5-2.5m away from the leeward side of the second retaining wall.

4. The application of a secondary anti-sand accumulation facility based on a windbreak wall according to claim 1 is characterized in that: The first windbreak wall set up on the road cutting is equipped with inclined plates.

5. The application of a secondary anti-sand accumulation facility based on a windbreak wall according to claim 4 is characterized in that: The included angle between the first windbreak wall and the inclined plate is 120° to 150°.

Images