CN116219817A - Method for high-filling embankment by wind-blown sand in desert area - Google Patents

Abstract

The invention discloses a method for filling embankments in desert areas with high wind-blown sand, and belongs to the technical field of road construction. The method for filling the embankment by wind-blown sand in the desert area mainly comprises the following steps: pre-filling the roadbed to be filled, pushing the sand foundation by utilizing aeolian sand, layering initial pressure, sha Jichu flattening, leveling back pressure, vibrating and rolling the sand foundation, paving geotextiles and paving a natural gravel base layer; roadbed and slope protection are correspondingly carried out in the whole construction process. Through local materials and cooperation of the links, the quality of the high-fill desert embankment can be improved, a large amount of materials and manpower can be saved, and the construction method has higher economic and social benefits.

Description

Method for high-filling embankment by wind-blown sand in desert area

Technical Field

The invention relates to the technical field of road construction, in particular to a method for filling a embankment with wind-blown sand in a desert area.

Background

Along with the rapid development of the economy and the continuous perfection of foundation construction projects in China, the development of the China and the construction of the Xinjiang in the south are continuously promoted in recent years, the establishment of the Xinjiang desert roads is accelerated, the communication and the communication of the south-north Xinjiang are accelerated, and the method has important significance for promoting the conversion of the resource advantage to the economic advantage in the south-Xinjiang area.

However, the road construction in the desert area is complex, a large amount of materials and manpower are needed, and the quality is still to be further improved.

In view of this, the present invention has been made.

Disclosure of Invention

The invention aims to provide a method for filling a embankment with wind-blown sand in a desert area, which can improve the quality of the embankment with high-fill wind-blown sand, save a large amount of materials and manpower and has higher economic and social benefits.

The application can be realized as follows:

the application provides a method for highly filling embankment by wind-blown sand in a desert area, which mainly comprises the following steps: pre-filling the roadbed to be filled, pushing a sand foundation, layering initial pressure, sha Jichu flattening, leveling back pressure, vibrating and rolling the sand foundation, paving geotextiles and paving a natural gravel base layer; roadbed and slope protection are correspondingly carried out in the whole construction process;

wherein the roadbed filler is aeolian sand.

In an alternative embodiment, the pre-fill process includes: and (5) lofting a roadbed and treating the surface layer of the foundation.

In an alternative embodiment, the ground surface treatment thickness is 20-30cm.

In an alternative embodiment, the pushing the sand base includes: pushing from both sides of the route or taking material from along the wind volume Sha Liaochang.

In an alternative embodiment, each layer is filled to a thickness of 50-60cm.

In an alternative embodiment, the content of the sticky fine particles of the aeolian sand powder is not more than 25% when the roadbed is filled, and the salt content meets the XJTJ01-2001 requirement.

In an alternative embodiment, the stratified primary pressure comprises: after each pushing layer, leveling and rolling until the lofting elevation is reached.

In an alternative embodiment, the planing is performed using a bulldozer, more preferably a crawler bulldozer.

In an alternative embodiment, the planing is performed by a crawler dozer with a free-running capacity of 320 horsepower or more and a dead weight of 30t or more in the desert.

In an alternative embodiment, the number of passes during the initial lamination is 4-6.

In an alternative embodiment, leveling the back pressure includes: the method is carried out by adopting a self-propelled grader.

In an alternative embodiment, the power of the motor grader is above 180 KW.

In an alternative embodiment, the number of repressions is 2-3 passes.

In an alternative embodiment, vibratory compaction comprises: the method is carried out by adopting a high-power vibratory roller with the power of more than 20 t.

In an alternative embodiment, the high power vibratory roller operates at a high frequency of 34-50HZ and a stand of 0.6mm.

In an alternative embodiment, the unit vibration is rolled for 2-3 times during vibration rolling, and the rolling speed is not more than 6km/h.

In an alternative embodiment, laying a geotextile comprises: and paving the coiled geotextile on the flattened sand foundation along the trend of the road.

In an alternative embodiment, each segment laid is 150-200m in length.

In alternative embodiments, aeolian sand or natural gravel is used to press against the laying edges and/or lap joints.

In an alternative embodiment, overlapping lap joints are adopted at the joints of geotextiles, the transverse lap joint width is not less than 50cm, and the longitudinal lap joint length is not less than 50cm; more preferably, the joints of the geotextile are sewn by thin iron wires or nylon ropes; even more preferably, the stitch pitch is not less than 30cm.

In an alternative embodiment, the geotextile is model WJ80/PP.

In an alternative embodiment, after the geotextile is laid, vibratory compaction is performed to tightly bond the geotextile to the sand foundation, which in turn can further densify the sand foundation surface.

In an alternative embodiment, paving a natural gravel base layer comprises: paving by adopting a reverse pushing method.

In an alternative embodiment, a rolling step is included between the paving of the natural gravel base and the slope protection.

In alternative embodiments, natural gravel is leveled, and then is rolled 4-6 times with static rollers of 18 tons or more, or is vibrated 2-3 times with vibratory rollers, without sprinkling water.

In an alternative embodiment, the subgrade and slope protection comprises at least one of the following:

mode one: when the wind-packed sand is adopted to fill the roadbed in the section with the slope rate of the high-fill desert roadbed slope of 1:3, grass is made on the slope surface of the slope and grass square grid sand fixation protection is arranged;

mode two: widening each side of the aeolian sand subgrade;

preferably, the width is widened to 50cm; more preferably, the widened portion is constructed simultaneously with the fill body.

Mode three: laying a woven geotextile reinforcing layer on the top surface of the aeolian sand;

mode four: and (5) grass square side slope protection and/or high vertical sand-blocking fence protection are carried out.

In an alternative embodiment, grass grid sand fixation protection is adopted on two sides of the roadbed.

In an alternative embodiment, the grass grid is made of aquatic reed.

The beneficial effects of this application include:

the method for setting the wind-blown sand high-fill embankment in the desert area mainly comprises the following steps: pre-filling the roadbed to be filled, and then sequentially pushing a sand foundation, layering initial pressure, sha Jichu flattening, leveling back pressure, vibrating and rolling the sand foundation, paving geotextiles and paving a natural gravel base layer; roadbed protection is correspondingly carried out in the whole construction process; wherein the roadbed filler is aeolian sand. The wind-blown sand is used as roadbed filling, local materials are obtained, and the engineering cost can be effectively saved. Through the cooperation of the links, the quality of the embankment with high filling rate can be improved, a large amount of materials and manpower can be saved, and the method has higher economic and social benefits.

Drawings

In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the drawings that are needed in the embodiments will be briefly described below, it being understood that the following drawings only illustrate some embodiments of the present invention and therefore should not be considered as limiting the scope, and other related drawings may be obtained according to these drawings without inventive effort for a person skilled in the art.

FIG. 1 is a schematic view of a grass square;

FIG. 2 is a schematic plan view of a sand dune after grid arrangement;

FIG. 3 is a schematic view of a high vertical sand barrier;

FIG. 4 is a schematic diagram of a binding method of a high vertical sand barrier.

Detailed Description

In order to make the objects, technical solutions and advantages of the embodiments of the present invention more clear, the technical solutions of the embodiments of the present invention will be clearly and completely described below. The specific conditions are not noted in the examples and are carried out according to conventional conditions or conditions recommended by the manufacturer. The reagents or apparatus used were conventional products commercially available without the manufacturer's attention.

The method for filling the embankment with the wind-blown sand in the desert area is specifically described below.

A method for highly filling embankments in a desert area by wind-blown sand mainly comprises the following steps: pre-filling the roadbed to be filled, pushing a sand foundation, layering initial pressure, sha Jichu flattening, leveling back pressure, vibrating and rolling the sand foundation, paving geotextiles and paving a natural gravel base layer; roadbed protection is correspondingly carried out in the whole construction process.

Wherein, the roadbed filler is aeolian sand, and local materials are taken, so that the engineering cost can be effectively saved.

Before the pre-filling treatment, the method further comprises the step of roadbed design. For example, during design, the side slope is slowed down as much as possible, and a natural curved surface is formed to be integrated with the original landform, so that the vehicle is beautified and the driving safety is improved.

For reference, the pre-fill process includes: and (5) lofting a roadbed and treating the surface layer of the foundation.

Wherein, the roadbed lofting can be referred to: the subgrade edge is firstly put out according to the design drawing, the pre-sinking degree is considered when the embankment is lofted, and the pre-sinking degree value is considered according to the test result of the test section, and is generally about 3% of the filling height.

The foundation surface treatment can be referred to as: the surface turf, humus soil and shallow saline soil are removed, and then rolled before filling, and roadbed is directly filled after the compaction degree requirement is met, wherein the surface cleaning thickness can be 20-30cm, such as 20cm, 25cm or 30cm, and the like, and can be any other value within the range of 20-30cm.

Further, pushing the sand base may include: after the pay-off is designed according to the construction drawing, pushing is carried out from two sides of the route or the material is taken from the wind area Sha Liaochang along the route.

Preferably, the filling thickness (desired thickness) of each layer may be 50-60cm, such as 50cm, 55cm or 60cm, and the like, and may be any other value within the range of 50-60cm.

The filling can be carried out on site by adopting a dry compaction method, and preferably, the dry compaction can be carried out by adopting a large-tonnage vibratory roller.

When the wind-deposited sand fills the roadbed, grass, tree roots and the like mixed in each layering are removed in time. The content of the sticky fine particles of the aeolian sand powder is preferably controlled to be not more than 25% during roadbed filling, and the salt content therein cannot exceed the standard (according to XJTJ 01-2001).

The stratified primary pressure may include: after each pushing layer, leveling and rolling until the lofting elevation is reached.

For reference, bulldozers, preferably crawler dozers with a free-running capacity of 320 horsepower or more and a dead weight of 30t or more in the desert, may be used for leveling.

The number of passes during the initial lamination may be 4-6 passes (e.g., 4 passes, 5 passes, or 6 passes, etc.).

The leveling and back-pressing can be performed by adopting a self-propelled land leveler, and preferably, the power of the self-propelled land leveler can be set to be more than 180KW so as to ensure normal work when leveling the sand foundation.

Preferably, the construction is best to ensure the re-compression quality of the widening section and ensure the tire to be rolled for 2-3 times (namely, the number of re-compression times is controlled to be 2-3 times).

The vibration rolling can be performed by a high-power vibratory roller which can normally work on a sand foundation by more than 20 t.

The working high frequency of the high-power vibratory roller can be 34-50HZ (such as 34HZ, 35HZ, 36HZ, 37HZ, 38HZ, 39HZ or 40HZ, etc.), and the abutting amplitude can be 0.6mm.

In the above-mentioned vibration rolling process, it may be preferable to roll 2 to 3 times per vibration, the rolling speed being not more than 6km/h.

The sand foundation is flattened after vibrating compaction, so that the width, arch, elevation and the like of the roadbed meet the design requirements.

Further, laying the geotextile comprises: and paving the coiled geotextile on the flattened sand foundation along the trend of the road.

The length of each segment laid may be, for example, 150-200m, such as 150m, 160m, 170m, 180m, 190m or 200m, etc., or any other value in the range of 150-200m.

When the geotextile is paved, the geotextile is stretched and flattened, and the incomplete part is covered by another piece of woven cloth (the length and the width are 50cm more than the incomplete part).

To prevent lifting by wind, small amounts of wind-blown sand or natural gravel may be spread on the edges, joints, etc. to hold it down. Overlapping lap joints are adopted at the joints of geotextiles, and preferably, the transverse lap joint width is not less than 50cm, and the longitudinal lap joint length is not less than 50cm; more preferably, the joints of the geotextile are sewn by thin iron wires or nylon ropes with smaller extensibility, and the stitch pitch is not less than 30cm.

For reference, the geotextile used may be of the model WJ80/PP. The fabric has a part of the properties shown in tables 1 and 2.

TABLE 1 physical Property parameters of woven geotextile WJ80/PP

TABLE 2 other Properties of woven geotextile WJ80/PP

In an alternative embodiment, after the geotextile is laid, vibratory compaction (e.g., using a vibratory roller) is performed to tightly bond the geotextile to the sand bed, while also further compacting the sand bed surface. In addition, the geotextile and sand gravel base layer can be sprayed with water, vibrated and rolled (such as 3-4 times) together with the natural gravel base layer after being paved.

In this application, paving the natural gravel underlayment may be performed using a reverse push method.

Specifically, a reverse pushing method is adopted for paving, the dumper turns around and backs, the dumper is unloaded on a gravel layer with a slightly thick working surface, the dumper leaves, a bulldozer is used for paving the gravel material on a geotechnical cloth sand foundation, and a grader is used for fine leveling.

In an alternative embodiment, a rolling step is included between the paving of the natural gravel base and the slope protection.

Further, after leveling the natural gravel, the natural gravel is firstly rolled for 4-6 times (such as 4 times, 5 times or 6 times) by a static road roller with more than 18 tons or is vibrated and rolled for 2-3 times by a vibratory road roller.

Roadbed and slope protection is also contemplated herein and may include, for example, at least one of (and preferably all of) the following:

mode one: when the wind-packed sand is adopted to fill the roadbed in the section with the slope rate of the high-fill desert roadbed slope of 1:3, grass is made on the slope surface of the slope and grass square grid sand fixation protection is arranged.

Mode two: widening (e.g., widening to 50cm in width) is performed on each side of the aeolian sand subgrade, and preferably, the widening is performed simultaneously with the filling body.

Mode three: a woven geotextile reinforcing layer (such as WJ80 woven geotextile) is paved on the top surface of the aeolian sand, so that gravel can be prevented from being pressed into the aeolian sand, and the bearing capacity of a roadbed can be improved; on the other hand, the plate body effect of the roadbed can be enhanced, and the crack of the road surface caused by the peristaltic movement of dry sand under the working condition is prevented.

Mode four: and (5) grass square side slope protection and/or high vertical sand-blocking fence protection are carried out.

Wherein, grass square side slope protection can be referred to: according to the characteristics of the terrain, the topography, the geological conditions, the weather, the hydrology and the like of the area where the route passes, the safety, the stability, the environmental protection and the economy are taken as basic criteria, and grass grids are adopted on two sides of the roadbed for sand fixation protection.

Specifically, the raw annual aquatic reed is cut into pieces with the length of 70cm for standby. The land where grass square grids are planted is preferably made smooth before construction, the embankment adopts a slow slope cross section mode, and the slope rate of the embankment slope is determined according to the filling materials, the filling soil height, the wind direction, the road side topography and the protection condition; firstly, the design is considered by means of slowing down the slope rate of the slope, widening the platform and the like, and the self stability of the slope is pursued. For the high slope, the reinforcement measures can be combined to prevent steep slopes, the connection is smooth and suitable, the artificial mark is eliminated, the longitudinal and transverse transplanting lines are determined, the cut spare reed is placed perpendicular to the lines, and the middle position of the cut spare reed is placed on the lines. Then, the sand is forced to be pressed into the quicksand by 15cm along the line by a flat-head shovel, and exposed for 20cm. Then, the reed is shaped and straight and smooth by a spade or a foot, the two sides of the grass belt are backfilled with the foot and are compacted (which can be understood as leveling, sealing and compacting). Finally, the sand in the center of the grass square grid is scraped outwards by a spade, so that a low-lying arc shape is formed in the grass square grid, and the square grid is stable and the sand is accumulated. Preferably, the consumption of the reed is 1.2kg per 1 reed grid reed. In the above process, the schematic view of the structure of the grass square grid may be referred to fig. 1, and the schematic view of the sand hill plane after the square grid is set may be referred to fig. 2.

It should be noted that, the life of grass grid material adopts aquatic reed for 3-5 years, the specific life varies with topography and regional climate, and in construction and later maintenance management stage, grass grid sand is buried in early stage and should be maintained in the protection system outside to slow down the trend of killing from slight to serious, the life of grass flat sand barrier should be fully utilized for 3-5 years, the seedling stage of biological sand prevention is implemented as soon as possible, thus the total life investment of sand prevention and fixation is minimum and the benefit is maximum.

The protection of the high vertical sand-blocking fence can be referred to as follows: the sand blocking fence is arranged on the sand falling slope along the sand hill falling slope direction, and when the sand blocking fence must pass through, the sand falling slope (higher position) is preferably directly penetrated, so that the crossing distance is reduced. The reed fence is connected with the wooden piles through thin iron wires, the upright posts and the tightening iron wires are firstly implemented during construction, the X-shaped reinforcing iron wires on the leeward surface and the X-shaped reinforcing iron wires are positioned on two sides of the reed fence, the upper end and the lower end of the reed fence are provided with transverse iron wires (connected with reeds through binding wires), and the lower end of the reed fence is consistent with the upper part of the reed fence. The wooden sticks with the interval of 3m are provided with short wooden sticks and inclined pull iron wires (the length is 50 cm) which are inserted into sand or secondary Lin Bantiao with the diameter of 50-60mm is more than or equal to 40cm and bundled, the horizontal iron wires are embedded into sand soil for 40-60cm (plumb depth), the upper sand is stepped on after the embedding, and the inclined pull iron wires are inclined pull on a fixed design position for fixing the wooden sticks and the lower part of a fence, so that the erosion is avoided.

Preferably, the sand blocking fence is arranged at the outer side of the grass square, and a spare belt with a distance of about 12-20m with the sand fixing grass square is used for accumulating external accumulated sand, and the sand blocking fence is arranged at a position 1-2m away from the ridge line on the windward side of the sand dune. The sand blocking fence avoids oblique crossing and is prevented from being arranged in the falling sand slope along the falling sand slope direction of the sand dune. 3 sand-blocking fences should be arranged on the road section with serious sand damage. The statistics of the main wind direction should be closely paid attention to during construction; when the main wind direction is right to left, 3 sand-blocking fences are arranged on the right of the road, and when the main wind direction is undefined, 2 sand-blocking fences are respectively arranged on the left and right. According to the position and the state of a sand hill, a first sand blocking fence is arranged at a distance of 12-20m from a grass square lattice, a second sand blocking fence is arranged at a distance of 12-20m from the first sand blocking fence, the sand blocking fence is fixed by adopting reed, 1 wood stick (5 cm multiplied by 210 cm) is arranged at a distance of 3m, the wood sticks are nailed into sand for 70cm and exposed for 140cm, 2X-shaped reinforcing iron wires are respectively arranged at two sides of a net surface between two upright posts of the high vertical sand blocking fence (namely, reed or PE net is arranged in the middle of the X-shaped reinforcing iron wires), a transverse reinforcing iron wire is respectively arranged at the upper end and the lower end of the high vertical sand blocking fence, fixing piles (materials are arranged on two sides of the upright posts in the direction of the sand blocking fence, and the upright posts are tensioned by traction iron wires (the length is about 450 cm) and the length of the steel wires are not smaller than 40cm. Two grass square grids (1.0 m multiplied by 1.0 m) are respectively arranged at two sides of the bottom of the high vertical sand barrier, and the total width is 4m. In the above process, the structure of the high vertical sand-blocking fence (PE nylon net) is shown in FIG. 3, and the binding method of the high vertical sand-blocking fence is shown in FIG. 4.

It should be noted that, when performing the specific construction according to the method provided in the present application, the following aspects are preferably noted:

A. the selection of the construction mechanical equipment ensures that the construction mechanical equipment meets the related technical requirements in the engineering of selecting the mechanical equipment, and also carries out management and control activities according to factors such as the scale condition, the site condition and the like of the engineering, and carries out comprehensive treatment on the mechanical equipment under the condition of ensuring the walking stability of the mechanical equipment. The test efficiency and quality of mechanical equipment are improved, the phenomena of roadbed damage and the like are avoided, and the working mechanism is comprehensively optimized.

B. Good lap joints must be ensured in the process of laying geotextiles, and special persons should be dispatched to check and patrol. The wind volume Sha Dingmian is paved with geotextile, and large particles in the material should be detected.

C. When the wind-deposited sand is utilized to fill the roadbed in the non-desert section, gravel and edge-pasting soil should be arranged on two sides of the wind-deposited sand roadbed.

D. Constructing a road section by adopting a dry pressing method, and adopting a large-tonnage vibratory roller; care should be taken during the mechanical operation to avoid the hard objects from damaging the geotextile.

E. When the aeolian sand fills the embankment, grass, tree roots and the like mixed in each layered layer need to be removed in time; the laid geotextile must be covered in time to avoid loss of strength due to insolation.

F. Ensuring the compactness of each filling.

G. The reed (grown in one year) is not discolored, mildewed and elastic, and the reed with a diameter smaller than 5mm cannot be used as grass square. b. The construction is that firstly upwind side and then downwind side, sand barrier is firstly blocked, then reed fixes sand square, the whole section of reed square is pushed, the grass square range is rough flat to form roadbed side low and outer side high, and a vertical barrier is formed at the position of about 2-3m of the top wind direction of the ridge line, the ridge line is flat and must not have sand dunes or sand silts or sand pits with relative height difference (3 m length) of 50 cm. c. Slope grass square lattice construction is carried out from the top to the bottom, and 1 grass square lattice is planted at the brow line; and prohibiting the grass square from being arranged on the falling sand slope. d. The transverse fireproof isolation belts perpendicular to the road are arranged at intervals of 300m in the direction of the grass square lattice of the rock road, the width is 2.0m, and the surface firewood is cleaned in the fireproof isolation belts. e. In a dense region of sand dunes, the device should be arranged along the low-wind area between sand dunes, forbidden to be arranged on slopes, sand dunes and windward slopes, and should be arranged on flat sand lands perpendicular to the main line synthesis direction.

H. The road shoulder construction method comprises the following steps: paving geotextiles, pulling natural gravel, unloading along the line, manually paving and leveling, and vibrating and rolling for 2-3 times by using a small vibrating roller after sprinkling water.

I. The wind-blown sand roadbed filling belongs to the main application raw materials, is influenced by environmental factors, and has higher construction difficulty. Therefore, during actual construction, the project should reasonably use modes such as construction process test, construction drawing special design and the like to comprehensively control the construction quality. Under the condition of screening the optimal construction mode, good working results are obtained, and the method has profound significance for effectively utilizing aeolian sand in desert roadbed engineering.

On the way, the desert highway construction high-fill highway related in the application has at least the following advantages:

(1) A combined system of embankment filling, geotextile laying, grass square grid and sand blocking fence protection is developed by adopting a dry compaction method, so that the construction technology of the embankment with high wind-blown sand in the desert area is developed.

(2) Wind-blown sand is used as a embankment to be filled into a good embankment structure. The filling material of the aeolian sand embankment mainly comes from large local materials, reduces borrowing and filling, and has high roadbed construction speed.

(3) The dry compaction method solves the problem of embankment water resources in desert construction, and not only can the construction quality be ensured, but also the construction progress can be ensured.

(4) The quality of roadbed filling is within a controllable range through strict requirements and selection of construction machinery, and the qualification rate reaches 100%.

(5) The road shoulder part is constructed according to the method, so that the phenomenon that the pavement structure layer is not collapsed or equipment is turned on one's side can be avoided, and the rolling efficiency and quality of the related structure are comprehensively improved.

(6) And by paving geotextiles, the stability and the overall quality of the embankment are ensured. The settlement after embankment construction is uniform and is within the design range.

(7) The reed is used as grass square to kill the grass, the local materials are obtained, and the implementation effect is obvious.

The technology takes engineering as an object and a process as a core, not only can obviously enhance the quality of the embankment filled with high altitude, but also can obtain local materials, save a great deal of materials and manpower, and obtain obvious economic and social benefits.

Test examples

The method is applied to third-engineer pattern wood Shu Keshi-fourteenth Shi Kun jade city roads (third-engineer section) and fourth contract section (K70+100-K125+ 945.26. The contract section adopts secondary road standard construction, the whole route length is 55.845km, the initial pile number K70+100-K125+ 945.26, the width of roadbed is 12.0m, the design speed is 80km/h. The contract section is positioned at the Western edge of Takara-Lema dry desert.

TABLE 3 topography conditions

Sequence number	Line pile number	High sand hill ratio
			1	K70+100～K71+300	10-20m
2	K71+300～K76+800	10-30m
			3	K76+800～K87+100	10-20m
4	K87+100～K112+500	5-10m
			5	K112+500～K126+000	10-25m

Aiming at the geomorphic of the desert area, the project area is divided into a semi-fixed bush sand hill area, a compound crescent sand hill group, a fish scale sand hill group, a compound crescent sand hill chain, a gobi denudation area, a compound sand ridge and a flat land among chains according to the on-site investigation, and the current situation is as follows:

1. semi-fixed bush sand hill area

The whole sand dune is short and small, the height is 0.5-8m, and the average height is 2.8m. The vegetation is relatively developed, the vegetation coverage rate is about 30%, and the hills are mostly monster willows and populus, and the hills and the depressions are mostly grown with reed and shuttle.

2. Compound crescent sand hill group

The crescent sand hill chain is overlapped with a crescent sand hill or sand hill chain of the next stage on the windward side, the density of the sand hill is more than 95%, the maximum height of the sand hill is 15m, the minimum height is 2m, and the average height is 4m.

3. Fish scale dune group

The crescent sand dunes are tightly connected in the longitudinal and transverse directions, the sand dunes are continuous in wave shape and are arranged in northwest directions, the overall distribution is similar to fish scales, the density of the sand dunes is approximately 100%, the maximum height of the sand dunes is 20m, the minimum height is 2.8m, and the average height is 5m.

4. Composite crescent sand hill chain

The sand hill chains are distributed in the east-west direction as a whole, the lines pass through fish scale sand hill groups among the chains, the density of the crescent sand hill is approximately 100%, the maximum height is 25m, and the minimum height is 5m.

5. Eroding gobi area

The fan is washed and deposited in front of the Mazataghan mountain, the overall topography is flat, the local undulation is present, wind erosion hills are occasional, and island-shaped high lands are formed.

The roadbed filled by the project above 8m has more than 195 parts. The highest fill height section reaches 18m, as shown below.

By the method for filling the embankment in the desert area with the wind-blown sand, construction is started from 5 months of 2022, traffic is monitored and opened in real time, various indexes are good, and the operation is stable and normal in running, so that the roadbed construction quality reaches the standard.

In conclusion, the method for the wind-blown sand high-fill embankment in the desert area can improve quality of the embankment with high fill, save a large amount of materials and labor, and has high economic and social benefits.

The above is only a preferred embodiment of the present invention, and is not intended to limit the present invention, but various modifications and variations can be made to the present invention by those skilled in the art. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention should be included in the protection scope of the present invention.

Claims (10)

1. The method for high-filling embankment by wind-blown sand in the desert area is characterized by mainly comprising the following steps of: pre-filling the roadbed to be filled, pushing a sand foundation, layering initial pressure, sha Jichu flattening, leveling back pressure, vibrating and rolling the sand foundation, paving geotextiles and paving a natural gravel base layer; roadbed and slope protection are correspondingly carried out in the whole construction process;

wherein the roadbed filler is aeolian sand.

2. The method for highly filling a embankment in a desert area by wind-blown sand according to claim 1, wherein the pre-filling treatment comprises: setting out a roadbed and treating the surface layer of the foundation;

preferably, the foundation surface treatment thickness is 20-30cm.

3. The method for highly filling a embankment in a desert area by wind-blown sand according to claim 1, wherein pushing the sand base comprises: pushing from both sides of the route or taking material from along the wind volume Sha Liaochang;

preferably, each layer is filled with 50-60cm thick;

preferably, when the roadbed is filled, the content of the sticky fine particles of the aeolian sand powder is not more than 25%, and the salt content meets the XJTJ01-2001 requirement.

4. The method for high-fill embankment in desert areas by wind-blown sand according to claim 1, wherein the layered initial compaction comprises: leveling and rolling after each pushing layer until reaching the lofting elevation;

preferably, the levelling is carried out using a bulldozer, more preferably a crawler bulldozer;

preferably, the crawler dozer with more than 320 horsepower and more than 30t dead weight which can walk freely in the desert is adopted for leveling;

preferably, the number of passes during the initial lamination is 4-6.

5. The method for highly filling a embankment in a desert area by wind-blown sand according to claim 1, wherein leveling and repressing comprises: adopting a self-propelled grader;

preferably, the power of the self-propelled grader is more than 180 KW;

preferably, the number of double presses is 2-3 times.

6. The method for high-fill embankment in desert areas by wind-blown sand according to claim 1, wherein the vibration rolling comprises: adopting a high-power vibratory roller with the power of more than 20t to carry out;

preferably, the working high frequency of the high-power vibratory roller is 34-50HZ, and the propping amplitude is 0.6mm;

preferably, in the vibration rolling process, the unit vibration rolling is carried out for 2-3 times, and the rolling speed is not more than 6km/h.

7. The method for wind-blown sand high-fill embankment in a desert area according to claim 1, wherein the laying of geotextiles comprises: spreading the coiled geotextile on a flattened sand foundation along the trend of the road;

preferably, each section laid is 150-200m in length;

preferably, aeolian sand or natural gravel is used to press against the laying edges and/or lap joints;

preferably, the joint of the geotextile adopts overlap joint, the transverse overlap joint width is not less than 50cm, and the longitudinal overlap joint length is not less than 50cm; more preferably, the joints of the geotextile are sewn by thin iron wires or nylon ropes; even more preferably, the stitch pitch is not less than 30cm;

preferably, the geotextile is model WJ80/PP;

preferably, after the geotextile is laid, vibratory compaction is performed to tightly bond the geotextile to the sand foundation.

8. The method of high wind-blown sand embankment in a desert area according to claim 1, wherein the paving of the natural gravel base layer comprises: paving by adopting a reverse pushing method.

9. The method for highly filling a embankment with aeolian sand in a desert area according to claim 1, characterized in that the step of rolling is also included between the paving of the natural gravel base layer and the slope protection;

preferably, natural gravel is leveled, and is not sprayed first, and is rolled for 4-6 times by a static road roller with the weight of more than 18 tons or is vibrated and rolled for 2-3 times by a vibratory road roller.

10. The method of high wind-blown sand embankment in a desert area according to claim 1, wherein the roadbed and slope protection comprises at least one of the following means:

mode one: when the wind-packed sand is adopted to fill the roadbed in the section with the slope rate of the high-fill desert roadbed slope of 1:3, grass is made on the slope surface of the slope and grass square grid sand fixation protection is arranged;

mode two: widening each side of the aeolian sand subgrade;

preferably, the width is widened to 50cm; more preferably, the widened portion is constructed simultaneously with the fill body;

mode three: laying a woven geotextile reinforcing layer on the top surface of the aeolian sand;

mode four: performing grass square side slope protection and/or high vertical sand barrier protection;

preferably, grass grids are used for sand fixation protection on two sides of the roadbed;

preferably, the grass grid is made of aquatic reed.

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