CN116377780A - Mountain highway high-fill roadbed filling construction method - Google Patents

Abstract

The application relates to the technical field of road construction, in particular to a mountain area highway high-fill roadbed filling construction method. The method comprises the steps of preparing work before construction; compacting treatment work of roadbed base before filling; filling roadbed; the stone-filled roadbed comprises substrate treatment, side slope stacking, layered filling and layered rolling; the roadbed is reinforced and compacted, and the high embankment with the height of the filled side slope being more than or equal to 20m and the embankment with the height of the half-filled side slope being more than 8m are compacted and reinforced by adopting impact compaction or a large-tonnage road roller; mixing and filling soil and stone; slope engineering, wherein a supporting and blocking reinforcement engineering is arranged on the slope; and observing the settlement of the roadbed, and monitoring the stability of the embankment with the side slope height exceeding 20m or the embankment with the ground slope rate steeper than 1:2.5, and the embankment with the potential stability hazard of the embankment by the foundation after half-filling and half-digging of the embankment and the retaining wall section. The method improves the safety and stability of the mountain highway high-fill embankment.

Description

Mountain highway high-fill roadbed filling construction method

Technical Field

The application relates to the technical field of road construction, in particular to a mountain area highway high-fill roadbed filling construction method.

Background

With the rapid development of the economy and the continuous perfection of foundation construction projects in China, the mountain highway construction projects are increased increasingly, and corresponding high-filling roadbeds are increased. The high-fill embankment means an embankment with a total height of more than 20.0m, and is classified into a range of high-fill embankment when the height is 6.0m or more in the case of filling with fine-grained soil in paddy fields or perennial ponding areas. The high-fill roadbed is easy to sink, and the problems of sliding of the side slope roadbed, cracking of the roadbed and the like seriously affect the normal operation of the road and the normal production and life of people. In the existing process of constructing the road at the bottom end of the mountain area, the phenomenon of instability of the high-filling embankment caused by different geology and landform occurs, so that the stability problem of the high-filling embankment of the mountain area road is to be solved.

Disclosure of Invention

The purpose of the application is to provide a mountain highway high-fill roadbed filling construction method to improve the safety and the stability of mountain highway high-fill embankment.

The mountain highway high-fill roadbed filling construction method provided by the application comprises the following steps:

step 100, preparing work before construction;

step 200, compacting treatment of roadbed foundations before filling;

wherein, include: adopting excavation reverse steps at the filling and excavating juncture, and filling and compacting the steps; for the obvious sedimentation difference, adopting the rigid-flexible transition treatment from filling to digging, and arranging longitudinal and transverse blind ditches at the filling and digging juncture or filling water permeable material treatment; a transition section is arranged in the excavation section in the longitudinal direction of the filling and excavation joint part, and geogrid treatment is paved on the transition section;

step 300, roadbed filling;

step 400, filling stone roadbed, including base treatment, side slope stacking, layered filling and layered rolling;

step 500, reinforcing and compacting roadbed, namely performing rolling and reinforcing on high embankments with the height of the filled side slope being more than or equal to 20m and embankments with the height of the half-filled side slope being more than 8m by adopting impact rolling or a large-tonnage road roller;

step 600, mixing and filling soil and stones;

step 700, slope engineering, slope setting supporting and reinforcing engineering;

And 800, observing roadbed settlement, and monitoring stability of the embankment with the side slope height exceeding 20m or the embankment with the ground slope rate steeper than 1:2.5, and the embankment with the hidden danger of stability on the embankment by the foundation after half-filling the half-excavated embankment and the retaining wall section.

Further, in step 200, the laying geogrid process includes:

a transition section is arranged in the excavation section in the longitudinal direction of the joint of the filling and the excavation, the length of the transition section is 10m, and when the longitudinal or transverse gradient of a ground line is steeper than 1:2.5 and the height of a filling slope is greater than 8m, a geogrid with an interval of 30cm between one layer and two layers is paved from bottom to top at a position 150cm away from the road surface;

the geogrid adopts a production process of integral punching and stretching molding, and the width is not less than 5m; when the excavation area of the half-filled and half-excavated road section is soil or soft rock, a geogrid is paved in the area of the roadbed of the junction part of the filling and excavation.

Still further, the laid geogrid treatment further comprises:

the road embankment side slope height is more than or equal to 20m, two layers of geogrids are arranged below 2m from the road surface and are respectively arranged at the positions of 2m and 2.3m below 2m from the road surface;

and (3) reinforcing the roadbed by adopting a large-tonnage road roller for the high embankment with the filling side slope height of more than or equal to 20 m.

Further, in the step 200, the method further includes a step of treating the bad foundation, including:

For bad foundation treatment at a mountain depression paddy field: the method comprises the steps of (1) in a mountain depression paddy field section, performing surface soil moisture softening, ditching, intercepting, draining surface water and underground water before filling, performing pre-filling compaction and embankment filling after draining and airing; adding a water accumulation pit for a difficult drainage road section, regularly pumping water in the water accumulation pit, and compacting or changing and filling before filling; setting a broken stone blind ditch or a seepage ditch on a road section with spring eyes or rich groundwater; the water-permeable material is replaced or the sand cushion is arranged, the sand cushion is treated, the replacement depth is controlled within 3m, and the replacement depth of a local small-range area can be deepened;

for poor foundation treatment of pond sections: the subgrade passes through the pond section and is treated by cofferdam, water pumping, dredging and/or filling replacement, and the slope of the subgrade is paved or laid to be 0.5m above the normal water level;

for bad foundation treatment of abandoned land: firstly, removing impurities and filling soil or backfilling qualified roadbed filling after treatment.

Further, in step 400, the substrate process includes: removing the floating stones, plain fill and sub-clay layers on the ground surface to a fragment-shaped strongly differentiated rock stratum, wherein the floating stones are used as embankment filling materials after being disintegrated, and the transverse slope of the foundation is steeper than 1:5, digging the ground into steps with the width not less than 2.0m, and rolling the surface cleaned and the foundation after digging the steps by using a vibratory roller;

The side slope stacking comprises: the embankment slope protection adopts block stone stacking, adopts a process mode of filling first and then stacking, and adopts stacking protection;

the layered filling comprises: the embankment is filled layer by layer, the loose laying thickness of each layer of the lower embankment is smaller than 45cm, the loose laying thickness of each layer of the upper embankment is smaller than 35cm, each layer of filler is filled twice, coarse-grain stone is filled first, the thick loose laying thickness is 3/4, coarse-grain layers are flattened and stabilized by a bulldozer, a layer of stone chips or stone residues is filled, the thick loose laying thickness is 1/4, the consumption of the thick loose laying thickness accounts for 15% -20% of that of the coarse-grain stone, gaps among large-grain materials are filled, and the large-tonnage bulldozer is used for flattening and spreading materials;

the layering rolling comprises: pressing the two sides and then pressing the middle, longitudinally parallel to each other, stabilizing, and re-pressing for 6-8 times by using a road roller with large tonnage.

Furthermore, in the side slope stacking, each level of road embankment side slope is stacked in a step type, and the stacking mode is as follows:

when the slope rate of the roadbed is 1:1.3, the width of the step is 26cm, and the height is 20cm;

when the slope rate of the roadbed is 1:1.5, the width of the step is 30cm, and the height is 20cm;

when the slope rate of the roadbed is 1:1.75, the width of the step is 35cm, and the height is 20cm.

Further, in step 700, the slope engineering includes:

when the height of the embankment is more than 8M, grass-spreading slope protection is carried out on the side slope by adopting an arch-shaped skeleton of the embankment, an intermediate protecting channel is paved by adopting M7.5 slurry masonry or precast blocks, tree planting positions are reserved, and when the height of the embankment is less than or equal to 8M, grass-spreading protection is carried out on the side slope;

the side slope of the filled stone embankment adopts stacking protection, and the relation between the height of the filled stone embankment and stacking thickness is as follows: when the height of the roadbed is less than 5m, the thickness is more than or equal to 1m; when the height of the roadbed is more than or equal to 5m and less than or equal to 12m, the thickness is more than or equal to 1.5m; when the height of the roadbed is more than or equal to 12m, the thickness is more than or equal to 2m; when the landscape requirements exist, the greening protection design can be considered; the minimum size of the stacking stone blocks is not smaller than 300mm;

the roadbed surface drainage is carried out on the principle of reducing the interference to the original water system as much as possible, and the roadbed drainage is provided with a side ditch, a intercepting ditch, a drainage ditch and a rapid trough; the underground drainage facilities such as blind ditches, seepage ditches and inspection wells are arranged in the underground drainage of the roadbed.

Further, in step 800, the monitoring frequency of the subgrade settlement observation is:

monitoring frequency, observing the embankment filling process once before filling a layer of soil, wherein the embankment filling lag period is shorter, the embankment filling lag period is longer, and the embankment filling lag period is observed once in one week; the embankment is filled to the period from the design elevation of the road groove to the pavement, and the embankment is observed once every half month or one month; after pavement is paved, observing every 3 months; the above detection frequency encrypts when it encounters a heavy rain.

Further, step 800 is followed by step 900 of providing auxiliary measures including embankment side ditches, blind ditches, infiltration ditches, tubular infiltration ditches and intercepting tubular infiltration ditches.

10. The method for filling and constructing a high-fill subgrade according to claim 8, wherein the embankment side ditch is connected with bridge and culvert in-out or cutting side ditches at two sides of the subgrade, the embankment side ditch adopts a serous rectangular side ditch, and when the embankment side ditch collides with a farmland drainage ditch, the ditch is changed and is connected with a water outlet of a drainage ditch or a culvert in sequence; the longitudinal slope of the side ditch is not less than 0.3%, and the distance between water outlets is not more than 300m;

a transverse broken stone blind ditch is arranged at a filling transition section of a roadbed, a longitudinal broken stone blind ditch is arranged at a side slope rock mass fissure water development section, a blind ditch is arranged at a spring opening dew point, underground water is led and discharged through a seepage ditch, and a blind ditch, a seepage ditch pipe type seepage ditch and a water interception pipe type seepage ditch are arranged at an underground water rich section;

when the final land after filling is still positioned at one side of the mountain, a drainage facility is arranged, besides a broken stone cushion layer arranged on the stratum, broken stone blind ditches are arranged on the surface of each backfill layer, one end of each blind ditch is connected with the original mountain, a water collecting channel of the original mountain is connected, and a reverse filtering layer is arranged at the outlet part.

Compared with the prior art, the high-fill roadbed filling construction method provided by the application adopts the filled stone embankment as the foundation, the embankment is paved with the geogrid, the roadbed and the combined drainage system are reinforced, and the safety and stability of the mountain road high-fill embankment are improved. The filling material of the filled stone embankment mainly originates from a large amount of stone excavation and tunnel abandonment, and is preferably applied to a foundation part of embankment construction. The rock-filled embankment is adopted, so that the embankment can be reinforced to ensure the stability of the embankment, and the problem of underground water can be solved. The settlement observation of the embankment with high filling can find out specific settlement indexes in construction, guide the next construction, and find hidden danger early at the same time, so that serious quality accidents after traffic are avoided, the settlement observation points are required to be arranged at road centers and road shoulders at two sides according to actual conditions, each filling is observed once, and if the filling interval of two times is longer, each 3d is observed at least once. In the engineering of constructing the middle and high filled embankment, compensation compaction is further carried out, on-site compensation compaction is carried out by adopting impact compaction, the settlement rate of the embankment is accelerated, the integrity of the embankment is improved, and the settlement after construction is reduced. The application of the geogrid in the construction process of the high-fill roadbed can enable the stress of the embankment to be more uniform, enhance the bearing capacity of the embankment, have extremely strong tensile capacity, are not easy to damage, and are beneficial to stabilizing the whole roadbed. The high-filling embankment can ensure engineering quality through roadbed substrate treatment, underground and ground drainage, embankment filling, roadbed reinforcement and application of corresponding auxiliary measures, has no problems of roadbed subsidence, slope sliding, cracking and the like, effectively prevents uneven settlement of high-filling roadbed, ensures that the roadbed consolidation rate reaches more than 99 percent, and basically completes roadbed settlement. The pavement diseases such as pavement cracking, sinking and collapse caused by differential settlement are effectively controlled, so that the maintenance cost of mountain road maintenance is greatly reduced, the service life of the road is prolonged, better quality benefits can be obtained in Europe, meanwhile, the strength of the high-fill embankment and the filling junction can be obviously enhanced to control settlement, local materials are available, a large amount of materials and manpower are saved, and obvious economic and social benefits can be obtained.

Drawings

In order to more clearly illustrate the embodiments of the present application or the technical solutions in the prior art, the drawings that are needed in the description of the embodiments or the prior art will be briefly described below, and it is obvious that the drawings in the following description are some embodiments of the present application, and other drawings may be obtained according to these drawings without inventive effort for a person skilled in the art.

Fig. 1 is a schematic structural diagram of a high-fill roadbed filling construction according to an embodiment of the present application;

FIG. 2 is a schematic diagram of a construction of a subgrade treatment for a lateral fill boundary according to an embodiment of the present application;

fig. 3 is a schematic structural view of a embankment with geogrid provided in an embodiment of the present application;

FIG. 4 is a schematic diagram of a section of settlement monitoring for a high-fill subgrade according to an embodiment of the present application;

FIG. 5 is a schematic diagram of a second section of settlement monitoring for a high-fill subgrade according to an embodiment of the present disclosure;

FIG. 6 is a graph of road bed filling compaction provided in an embodiment of the present application;

fig. 7 is a subgrade filling settlement graph provided in an embodiment of the present application.

Reference numerals:

100-high fill subgrade; 11-geogrid; 12-stone breaking blind ditches; 21-transition section; 22-surface soil; 30-a stone-filled embankment; 51-pavement structure layer; 52-the top of the roadbed; backfilling sandy soil on the road bed; 61-displacement observation marks; 70-ground line.

Detailed Description

For the purposes of making the objects, technical solutions and advantages of the embodiments of the present application more clear, the technical solutions of the embodiments of the present application will be clearly and completely described below with reference to the drawings in the embodiments of the present application, and it is apparent that the described embodiments are some embodiments of the present application, but not all embodiments. The components of the embodiments of the present application, which are generally described and illustrated in the figures herein, may be arranged and designed in a wide variety of different configurations.

Thus, the following detailed description of the embodiments of the present application, as provided in the accompanying drawings, is not intended to limit the scope of the application, as claimed, but is merely representative of selected embodiments of the application. All other embodiments, which can be made by one of ordinary skill in the art based on the embodiments herein without making any inventive effort, are intended to be within the scope of the present application.

Some embodiments of the present application are described in detail below with reference to the accompanying drawings. The following embodiments and features of the embodiments may be combined with each other without conflict.

As shown in fig. 1 to 7, an embodiment of the present application provides a method for filling and constructing a high-fill roadbed, including:

Step 100, preparing work before construction; wherein, include:

1. firstly, performing field investigation and check according to a design file, and lofting and retesting the middle pile elevation, the cross section, the central line and the lead according to a design drawing, so as to determine the middle pile section and the road land;

2. environmental conditions within the engineering scope, including geological conditions, hydrologic conditions, and drainage conditions, are investigated, and utility lines and structure conditions within the entire engineering scope are investigated. Investigation of other conditions such as a culvert, a ditch, a traffic transportation line and the like which are nearby a construction line and can be used for taking out soil;

3. and (3) performing on-site cleaning work, cleaning up trees and garbage in the roadbed range, digging out tree roots, burying and tamping. Furthermore, in order to better ensure the stability and strength of the embankment, sampling experiments can be performed on the filler, including experiments of material index, particle size, water content, density, strength and the like.

4. If groundwater and the like affect the stability of the roadbed, the seepage prevention, drainage and other works are performed by adopting drainage, interception, gravel filling, gravel, rubble and the like.

Step 200, compacting treatment of roadbed foundations before filling;

1. Weeds, shrubs, trees, humus soil, ponds, swamps and the like in the backfill range of the original field are clear and clean, and the thickness is about 30cm until original soil is seen;

2. the road foundation is required to meet the compaction requirements of compaction, uniformity and the like, and the compaction requirements are realized by adopting treatment measures such as filler replacement, lime doping, airing and the like; in addition, the road arch cross slope needs to be consistent with the base top surface cross slope, if the base soil is loose soil or cultivated soil, rolling treatment is needed, if the base soil is humus soil, cleaning is needed, the base compaction degree is ensured to exceed 85%, and meanwhile, drainage treatment, especially in rainy seasons, is needed to be enhanced; and further compacting the area with weaker surface foundation by adopting measures such as digging, replacing, rolling, low-energy-level dynamic compaction and the like, so that the bearing capacity of the foundation meets the standard requirement. If the original ground is positioned in the original catchment zone, a layer of water permeable material with the thickness of about 1m is paved after the original ground is treated so as to remove the original surface runoff.

Among them, 2.1, the treatment of bad foundations is mainly divided into the following cases:

first, poor foundation treatment at a paddy field of a mountain depression: the soil texture of the surface of the paddy field under the mountain is soft, ditching, intercepting, draining surface water and underground water are firstly carried out before filling, and compacting and embankment filling are carried out after draining and airing. For difficult drainage road sections, water accumulation pits should be added, and water in the water accumulation pits is regularly extracted, so that a good foundation construction site is provided. And finally compacting or replacing before filling. Depending on the field geological hydrologic situation, the following treatment measures are taken, as shown in fig. 2:

1. Drainage is performed by using a gravel blind ditch 12 or a seepage ditch. The broken stone blind ditch 12 or the seepage ditch is arranged on the road section with spring eyes or rich groundwater. The layout position of the gravel blind ditch 12 or the seepage ditch is adjusted by combining the topography and hydrogeology conditions on site. Forced drainage measures are adopted during construction, which are difficult to drain water in a relatively flat terrain, and off-line drainage facilities can be additionally arranged if necessary;

2. and (3) according to the conditions of roadbed stabilization and post-construction settlement, adopting a water permeable material to be replaced or a sand cushion layer to be arranged for treatment, controlling the replacement depth within 3m, and deepening the replacement depth of a local small-range area.

3. And (5) sand cushion treatment.

Secondly, poor foundation treatment of the pond section: the subgrade passes through the pond section and is treated by adopting cofferdam, water pumping, dredging, changing and filling and other modes, and the slope of the subgrade is paved or laid to be 0.5m above the normal water level.

Thirdly, treating bad foundations of abandoned land: firstly, removing impurities and filling soil or backfilling qualified roadbed filling after treatment.

Fourth, in the case of a low fill embankment, the depth of treatment of the bad foundations should not be less than the depth of the working area where the heavy truck loads.

2.2, the treatment of steep and sloping embankment and filling and digging juncture is mainly divided into the following cases:

First, for steep, sloped embankments and half-filled embankments: when the embankment is unstable or the filled area of the half-filled and half-excavated is a soft foundation, measures such as filling replacement, reinforcing rolling, reinforcing or retaining wall and the like are adopted for reinforcing treatment.

Secondly, because the soil property of the junction of the filling and digging junction is different in compactness, groundwater can exist, if the groundwater is improperly treated, uneven settlement of the roadbed can be caused, the roadbed deforms and cracks, even the roadbed is unstable, and the following requirements are met for the filling and digging junction:

1. for the longitudinal and transverse filling and digging junction and the natural ground transverse slope steeper than 1:5, a reverse step inclined inwards by 4% is dug on the original ground surface, the step width is not less than 2.0m, the step width of a high filling road section is not less than 3.0m, and the steps are filled and compacted to reach the compaction degree required by the standard, so that good combination of filling and digging interfaces is ensured; the method is characterized in that the stone road section is filled and excavated at the junction, and the settlement difference is obvious, so that the excavated steps are required to be subjected to rigid, flexible and mild transition from filling to excavation, and longitudinal and transverse road surface cracks are avoided; and arranging longitudinal blind ditches and transverse blind ditches at the filled junction according to the condition of groundwater or ground water, or filling a layer of water permeable material at the roadbed filling interface so as to facilitate the drainage of water in the roadbed.

2. As shown in fig. 1 to 3, a transition section 21 is arranged in the excavation section in the longitudinal direction of the joint of the filling and the excavation, the transition section 21 is 10m long, when the longitudinal or transverse gradient of the ground line 70 is steeper than 1:2.5 and the height of the filling slope is greater than 8m, one to two layers of geogrids 11 with the spacing of 30cm are paved from bottom to top at the position 150cm away from the road surface according to the requirement, and preferably, the geogrids 11 adopt three-way geogrids.

Table 1, geogrid Performance index Table

Table 2, high fill embankment laid geogrid engineering quantity table

3. For the road section of the transverse half-filling and half-digging, when the ground line 70 or the transverse gradient i is steeper than 1:2.5 and the height of the filling slope is greater than 8m, one to two layers of geogrids 11 with the interval of 30cm are paved from bottom to top at the position 150cm away from the road surface, and the geogrids 11 are produced by adopting a production process of integral punching and stretching molding, wherein the width is less than 5m.

4. When the excavation area of the half-filled and half-excavated road section is soil or soft rock, performing overexcavation and replacement or improvement treatment on the soil or soft rock of which the roadbed range of the excavation area is not in accordance with the requirement; the filling area is filled with a material with better water permeability, and when necessary, the geogrid 11 can be paved in the area of the road bed of the junction of the filling and digging. When the excavated area is hard rock, the fill area employs a rock-fill embankment 30.

2.3, high-fill roadbed conditions:

1. the road embankment side slope height is more than or equal to 20m, two layers of geogrids 11 are arranged below 2m from the road surface and can be respectively arranged at the positions below 2m and 2.3m from the road surface;

2. the high fill embankment filler is preferably filled with a filler having good engineering mechanical properties, and when a rock excavation is available, the rock filling embankment 30 is used.

3. For a high embankment with the height of the filled side slope being more than or equal to 20m, a road bed is reinforced by adopting a large-tonnage road roller, so that the filled soil of the embankment is enabled to obtain the maximum compactness, and the integrality and the strength of the embankment are improved.

Step 300, roadbed filling;

first, the test section construction is first performed before the subgrade filling is formally performed. The section form with the length more than or equal to 200m and the geological conditions and other typical strong sections are selected to be carried out, so that the optimal equipment type and combination mode, the loose paving thickness, the rolling speed, the rolling pass number and the like are determined.

Second, digging steps. When backfilling earthwork, the junction with the original mountain is subjected to step digging treatment, and the soil texture section with the ground transverse slope of 1:5-1:2.5 on a stable slope is firstly cleared up, as shown in figure 1, after surface soil 22 (the thickness of a paddy field section is 0.3m and the thickness of a common road section is 0.2 m), a step is dug, the width of the step is more than or equal to 2m, and the step is inclined inwards by 4%. For the stone section with the ground transverse slope of 1:5-1:2.5 and the thin covering layer on the bedrock surface, the covering layer is removed first and then the steps are dug, and when the bedrock surface is thicker and stable in covering, the covering layer can be reserved.

Thirdly, the filled roadbed is preferably selected from coarse-grained soil such as gravel soil, sand soil and the like with better grading, the maximum grain size of the roadbed filler is smaller than 100mm, the maximum grain size of the roadbed is smaller than 150mm, and the rule of 150mm of the maximum grain size of the embankment filler is not suitable for filling embankments and soil Dan Ludi. As shown in fig. 2 and 3, a road surface structure layer 51 is arranged above a road surface 52, and soil with good engineering mechanical properties is required to be filled 1.5m below the road surface 52 to backfill sand 53 on the road surface. The excavation can be used as embankment filling material along the normal road section of the subgrade. When CBR is less than or equal to 3 and the liquid limit of soil is high, the CBR can be used as embankment filler after 5% lime is added and stirred, and is preferentially used for embankment sections with embankment filling height less than or equal to 8 m. When the water permeable material is replaced by the highway subgrade, the water permeable material such as sand, gravel, rubble, broken stone and the like with good grading or sand with higher strength is adopted, and the physical limit meets the index requirement.

Step 400, filling stone roadbed;

firstly, because the stone road section is generally constructed by adopting a blasting method, big and small stones are mixed after blasting, and part of weathered rocks are easily weathered into stone chips and stone powder, so that the stone chips, the stone chips and the stone powder are mixed and are unfavorable for filling the embankment, when the embankment is filled with the stone slag, the bigger stones are subjected to small-size solving treatment so as to control the compaction quality.

Secondly, the particle size of the filler is strictly controlled in the process of filling the embankment, and the ultra-particle stone is required to be subjected to secondary lining solution, so that the ultra-particle stone cannot be dissolved and cannot be used for roadbed filling. For the cutting stone side as embankment filling, stone exploitation is utilized, and a dense deep hole millisecond differential blasting technology is adopted as much as possible, so that the rock burst degree of 80% is 20-30 cm.

Thirdly, qualified soil should be filled in the range of the roadbed, and the roadbed is compacted in layers. The top surface of the filling material should have no obvious pores or hollows. The top surface of the last layer of the stone-filling embankment 30 is provided with a transition layer, the thickness of the transition layer is not more than 400mm, the particle size of the stone stones of the transition layer is less than 150mm, and the content of fine materials less than 5mm is not less than 30%.

Fourthly, 30cm stone blocks are selected for stacking on the slope surface of the side slope of the stone filling embankment 30.

Fifthly, the construction process and scheme of the stone-filled roadbed are as follows: construction preparation, measurement and lofting, stone detection and qualified material transportation, stacking, spreading and leveling, removing or decomposing small super-grain filler, supplementing fine materials, manually leveling, rolling construction, quality inspection control, correction of unqualified road sections, lower layer filling after meeting the requirement, and otherwise, adjusting construction parameters for re-rolling.

Six, the stone-filled embankment adopts different filling layer thickness and compaction control standard according to stones with different intensities. The compaction quality criteria for the rockfill embankments 30 use porosity as a control index and meet the specifications of tables 3 to 5 below.

TABLE 3 hard rock compaction quality control criteria

Table 4, medium hard stone compaction quality control Standard

TABLE 5 Soft rock compaction quality control Standard

In addition, when it is difficult to use porosity as an index for controlling compaction quality, the compaction quality of the rockfill embankment 30 may also be controlled using the compaction differential settlement. If the compaction sedimentation difference is adopted for control, the following standard requirements are recommended for compaction sedimentation difference detection: the compaction sedimentation difference is the elevation difference of each measuring point after the heavy vibratory roller (more than 20 t) is adopted to roll according to the specified rolling parameters (strong vibration, speed less than 4 km/h) during construction rolling. The average value of the compaction sedimentation difference is not more than 5mm, and the standard deviation is not more than 3mm. Compaction quality standard for filled embankment 30: the compaction sedimentation difference and the porosity are used as control indexes, and the porosity is detected by adopting a water bag method. The compaction quality of the rockfill embankment 30 should be controlled by a combination of construction (compaction power, compaction speed, compaction pass, thickness of the pavement, etc.) and compaction quality detection.

The construction process of the stone filling roadbed comprises the following steps:

firstly, a test section is selected as a section which can represent the characteristics of a rectification section, the length of the test section is not less than 100m, and the area is more than 4000m ² And determining economic and reasonable filling thickness, rolling pass number and other parameters through a test road section.

Secondly, the substrate is treated, and in order to ensure the evenness of the evenness and the strength of the foundation and the bearing capacity requirement, the floating stones, the plain fill and the sub-clay layers on the ground surface are removed to form a fragment-shaped strong differentiation rock stratum. And stacking the flyrock at another position, and taking the flyrock as a embankment filler after being disassembled. The foundation cross slope is steeper than 1:5, the ground is dug into steps with the width not smaller than 2.0m, and the high-fill roadbed 100 needs to excavate large steps to ensure the stability of the roadbed and facilitate construction. And (3) cleaning the surface and digging the foundation after the steps, and rolling by adopting a vibratory roller to ensure that the compactness of the foundation meets the standard requirement.

Thirdly, the slope is built by stacking, the embankment slope is protected by stacking stones, the stacking thickness is 2m, and a process mode of filling first and then stacking is adopted. Each level of embankment side slope adopts step-type stacking, and the concrete stacking mode is as follows:

when the slope rate of the roadbed is 1:1.3, the width of the step is 26cm, and the height is 20cm;

when the slope rate of the roadbed is 1:1.5, the width of the step is 30cm, and the height is 20cm;

when the slope rate of the roadbed slope is 1:1.75, the step width is 35cm, and the height is 20cm;

the side slope of the filled embankment 30 adopts stacking protection, and stone used for stacking the side slope adopts stone with high strength and difficult efflorescence and disintegration when meeting water. And strictly forbidding the strong weathered stones to be used for roadbed slope construction. Meanwhile, large stones and stones with medium block degree are adopted for staggered bit, and a layer paving method and fine stone gap filling masonry are strictly forbidden. During the slope stacking construction of the filled-stone roadbed, stones are stacked one by one, the large surface faces downwards, and the placement is stable. The stones are tightly attached to the roadbed filling body as much as possible, are tightly contacted with each other and are mutually snapped, and obvious falling and loosening phenomena are avoided. The bearing contact surfaces among the stacking stone blocks incline inwards slightly to form a stable inward inclined structure, and the through seams, stacking and pasting are forbidden, so that the slope is flat as much as possible.

Fourth, the embankment is filled layer by layer, each layer of loose thickness of the lower embankment is smaller than 45cm, and each layer of loose thickness of the upper embankment is smaller than 35cm. Each layer of filler is filled twice, coarse-grain stone is filled first, and the thickness of the coarse-grain stone is about 3/4 of the loose-grain stone. Spreading and stabilizing coarse grain layer with bulldozer, filling one layer of stone scraps or slag, and loosening the coarse grain layer to 1/4 of thickness, wherein the coarse grain layer accounts for 15-20% of coarse stone, so as to fill gaps between large grain materials, and the paving layer should be relatively smooth, thus being beneficial to rolling. In addition, the fine particle layer which is compact after passing can play a certain role in blocking water, and rainwater infiltration in the construction period is reduced. The large-tonnage bulldozer is adopted for leveling and spreading, coarse and fine fillers are uniformly mixed in the leveling process, mutual extrusion of filler particles is enhanced, so that the filler particles have good flatness, and obvious pits, depressions or raised stones are avoided.

Fifth, the road embankment after being flattened is properly sprinkled with water by layering and rolling, so that stone movement and embedding shrinkage during rolling are facilitated. When the roller is pressed, the two sides (namely, the road shoulder part) are pressed firstly and then the middle part is pressed, the compaction route is longitudinally parallel to the roller, and stable measuring points are selected so as to facilitate observation in construction. After stabilization, re-pressing for 6-8 times by using a large-tonnage road roller, wherein the main reference technical indexes of the large-tonnage road roller are as follows: rated power 220KW, exciting force 590/450KN and maximum total acting force 810KN. The transverse overlapping is 40-50 cm and the longitudinal overlapping is 100-150 cm during the re-pressing, so that the leakage pressure and dead angle are avoided. The compaction degree of the embankment in the construction process is mainly controlled by a sedimentation difference method, and the embankment is rolled until the sedimentation difference reaches the standard requirement.

The quality detection of the filled-stone roadbed comprises the following aspects:

firstly, the loose pavement thickness is tested, measurement observation points are required to be distributed, a section is arranged at intervals of 20m along the longitudinal direction of a road, and each section is provided with one measurement observation point at intervals of 6-8 m from the center to 1.5m on each side. Each observation point is marked by red paint, and the position of each observation point is the same as the corresponding measurement point positioned at the lower layer. And measuring the elevation of the measuring point by using a level gauge before rolling, wherein the difference between the value and the elevation of the corresponding position of the lower layer is the actual measured loose thickness of the layer. The loose pavement thickness is based on the filling thickness determined by the test road section.

Secondly, apparent mass detection, namely compacting, loosening-free, wheel-trace-free and hollow-free roadbed surfaces after rolling, wherein the pick planing is not used for compacting and loosening the stone blocks, and the degree of loosening can be achieved only by prying with a crowbar. Special attention is paid to the sufficient rolling of the corner portions of the roadbed.

Third, compaction quality inspection, which may be controlled by differential settlement inspection, of the filled embankment 30 should be verified by porosity (by water bag) to determine the relationship between subsidence and compaction. When compaction sedimentation method is used for compaction degree detection, rolling is carried outAnd (3) arranging iron balls according to the following requirements after the sixth pass is finished, wherein the number of the iron balls is not less than 8, and carrying out seventh compaction. And after the seventh pass is finished, measuring the elevation of each iron ball, and implementing eighth pass compaction. And after the completion, measuring the elevation of each ball again, wherein the difference of the elevation of each ball is the compaction sedimentation difference, and calculating the sedimentation average value and the mean square error. And compared with a specified average value and a mean square error, the rolling is finished. If the compaction sedimentation difference does not meet the requirements, then rolling comprehensively, and measuring the compaction sedimentation difference according to the method until the compaction sedimentation difference of the last time and the previous time meets the requirements. In any case the mean sedimentation difference should be less than 5mm and the standard deviation less than 3mm. Each measuring point should represent an area of no more than 100m ² Detecting frequency every 2000m ² Detecting at least 12 points, wherein the compaction area is less than 200m ² At least 4 points are detected.

The requirements and layout of the iron ball are as follows: iron balls (or iron plates with the thickness of 10mm multiplied by D and more than 100mm, and 10mm semicircular nails are embedded in the middle), the diameter of each iron ball is more than 100mm, and the iron balls are distributed: the distance from the edge of the roadbed is not more than 2m, the longitudinal and transverse spacing is not more than 10m, and the roadbed is distributed in a quincuncial shape. Each filling construction section should be provided with a fixed level point at a proper position for pressure measurement and sedimentation.

The construction quality of the rockfill embankment 30 is mainly controlled by the construction process in combination with quality detection. In each working step, the maximum particle diameter of the filler, the thickness of the compacted layer, the number of rolling passes, the differential compaction sedimentation, and the like must be controlled strictly according to the predetermined requirements. In construction, the technician will record the compaction layer thickness, compaction pass number, and grain size of each layer of filling material in detail. For manager engineers to check at any time. After each layer is completed, intermediate inspection is required, reworking is required for the unqualified road sections, and construction of the next layer is performed after quality inspection is qualified.

Monitoring the horizontal displacement of the earth surface and the horizontal displacement of a deep soil body of the stone filling roadbed:

the method is characterized in that the method comprises the following steps of selecting the pile number with the most unfavorable section according to actual conditions, burying a deep sedimentation disc and an inclinometer pipe in the direction of the cross section of a roadbed, and detecting horizontal and vertical displacement to timely know the stability of the embankment. The monitoring period converges and stabilizes with the lateral displacement of the filling soil body. The settlement disk is used for observing the total settlement amount of soil bodies below the ground surface, the inclinometer pipe is used for observing the displacement of soil bodies at all layers of the foundation, and the inclinometer pipe is used for stably monitoring and knowing the lateral deflection of all layers of the soil bodies and the deflection development condition in the additional stress increasing process.

Step 500, roadbed reinforcement compaction:

as shown in FIG. 6, for high embankments with a fill side slope height of 20m or more and embankments with a half-fill side slope height of greater than 8m, impact rolling or large tonnage road rollers are adopted for rolling reinforcement. The method comprises the following steps:

first, impact rolling treatment, namely, the embankment is in principle carried out for 20 times when the embankment is filled up by about 2m, until the embankment is 30cm below the top surface 52 of the road bed, so that the overall strength of the road bed is effectively increased, the deflection value of the road bed is reduced, and the service life of the road surface is prolonged. The impact road roller should be carried out in a large area when punching and rolling the roadbed, and the length is at least more than 100m, so that the driving speed is improved and the excitation effect is improved when the road roller impacts. When the length of the filling section is smaller than 100m, the large-tonnage road roller rolls, strengthens and compacts.

Secondly, rolling and leveling by adopting a large-tonnage roller after rolling of a common roller is finished. The main technical indexes of the large tonnage road roller are as follows: rated power 220KW, exciting force 590/450KN and maximum total acting force 810KN.

Thirdly, carrying out reinforcing treatment by adopting dynamic compaction every time when the height of the dynamic compaction is about 5M, wherein the single-impact energy of each time is not less than 2000 KN.M, and the inspection quality is controlled by the compactness. The tamping times of the tamping points are determined according to a tamping times and tamping settlement relation curve obtained by field trial tamping, and the following conditions are satisfied at the same time: A. the average ramming amount of the last two strokes is not more than 50mm, and when the single stroke ramming energy is larger, the average ramming amount is not more than 100mm; B. excessive uplift should not occur on the ground around the tamping pit; C. the hammer lifting difficulty caused by too deep tamping pit is avoided. Furthermore, the number of the tamping passes is determined according to the property of the foundation soil, and can be 2-3 times, and finally the tamping is performed once again with low energy. The number of ramming passes may be increased appropriately if necessary. A certain time interval is applied between the two ramming passes. The interval time depends on the dissipation time of the hyperstatic pore water pressure in the soil. When the measured data is absent, the interval time of the embankment with poor permeability is not less than 3-4 weeks according to the permeability of the foundation soil; the road embankment with good permeability can be continuously tamped. The junction of the embankment, abutment and transverse structures (culverts and channels) should be provided with a transition section 21. The compactness of the roadbed 21 in the transition section is not less than 96 percent, and the filling, foundation treatment, a water-proof and drainage system of the bench back and the like are needed to be manufactured. When dynamic compaction is carried out, the impact point of the rammer needs to be determined through accurate measurement, the roadbed needs to be compacted in layers, the number of times of compaction and the force of different packing layers are different, and when the roadbed is filled to the last layer, the sinking depth of the dynamic compaction is required to be ensured to be lower than 2cm.

Step 600, mixing and filling soil and stones;

the filled roadbed belongs to a soil-stone mixture, the stone strength exceeds 20MPa, the maximum stone particle size is required to be not more than 2/3 of compaction degree, and if the stone strength is lower than 15MPa, the maximum stone particle size is required to be not more than compaction thickness. The particle size and the minimum strength of the filler meet the standard requirements, and the roadbed filled by the soil-stone mixture such as the block stone soil, the sheet stone, the pebble and the like is utilized. The filling must be layered and compacted, and the filling thickness needs to be combined with the mechanical specification and type, and is not more than 30cm. And detecting the compactness of the embankment by selecting a sand filling method.

Step 700, slope engineering;

roadbed disease control is carried out according to the local climate, hydrology, topography, geological conditions and road construction material conditions and the principle of combining engineering protection and plant protection, the roadbed is ensured to be stable, and the plant protection is adopted in the conditional road section as far as possible so as to recover the natural ecological environment to the maximum extent. And determining a slope protection form according to the slope stability condition and the surrounding environment, and arranging a supporting and reinforcing engineering for the slope with poor stability.

1. When the embankment height is more than 8M, the side slope adopts an arch-shaped skeleton of the embankment to broadcast grass (planted irrigation) side slope protection, the middle protecting road adopts M7.5 slurry masonry or precast block paving, and the tree planting position is reserved. And when the embankment height is less than or equal to 8m, grass sowing (irrigation) protection is adopted on the side slope.

2. The side slope of the filled-stone embankment 30 adopts stacking protection, and the relation between the height of the filled-stone embankment 30 and stacking thickness is as follows: when the height of the roadbed is less than 5m, the thickness is more than or equal to 1m; when the height of the roadbed is more than or equal to 5m and less than or equal to 12m, the thickness is more than or equal to 1.5m; when the height of the roadbed is more than or equal to 12m, the thickness is more than or equal to 2m. When the landscape is required, the greening protection design can be considered. The minimum size of the stacking stone blocks is not less than 300mm.

3. The roadbed surface drainage is carried out on the principle of reducing the interference to the original water system as much as possible, and the roadbed drainage is provided with a side ditch, a intercepting ditch, a drainage ditch and a rapid trough; the underground drainage facilities such as blind ditches, seepage ditches and inspection wells are arranged in the underground drainage of the roadbed. The blind ditches and the seepage ditches are used for reducing the groundwater level or removing groundwater rewet within the roadbed range.

Step 800, roadbed settlement observation;

for embankments with a side slope height exceeding 20m or embankments with a ground slope rate steeper than 1:2.5, and half-filled half-excavated embankments and retaining wall sections, the foundation is required to monitor stability of the embankment with potential stability hazards, and the monitoring frequency and period arrangement are as follows:

1. the frequency is monitored and the embankment filling process should be observed once before each layer of soil is filled. The embankment is filled and has a short stagnation period, one observation is carried out in one week, the stagnation period is long, and one observation is carried out in half a month; the embankment is filled to the period from the design elevation of the road groove to the pavement, and the embankment is observed once every half month or one month (determined according to the stability condition of the embankment); after pavement paving, observations were made every 3 months. The above detection frequency encrypts when it encounters a heavy rain.

2. Monitoring period, in order to guarantee the roadbed stability of roadbed construction and operation, monitoring time is arranged as: roadbed is filled up to the traffic for 2 years.

As shown in fig. 7, the settlement amount is an important index for evaluating engineering quality, and in the construction of high-fill roadbed 100, detection of the settlement amount of the roadbed can effectively control the construction quality, and the concrete degree of natural settlement of the roadbed can be obtained and can be used as a basic theoretical basis for the construction quality control so as to ensure that the roadbed is stable and reliable in use quality. The detection of the settlement amount of the high-fill subgrade 100 involves 3 parts, namely the settlement amount caused by the impact force of the high-fill subgrade 100, the gravity of the subgrade filling itself, the external force, and the like, and the horizontal moving distance of the high-fill embankment, and as shown in fig. 4 and 5, the displacement observation marks 61 are shown.

Step 900, auxiliary measures;

1. the embankment side ditch is arranged according to the drainage requirement of the embankment and is connected with bridge and culvert in and out or cutting side ditches at two sides of the roadbed, the embankment side ditch is made of a serous rectangular side ditch from the aspects of appearance and reduction of occupied area, and the size is generally 40cm multiplied by 50cm and 40cm multiplied by 60cm according to the catchment area. When the water collides with the farmland irrigation and drainage ditch, the ditch should be moved and connected with the water outlet of the drainage ditch or culvert in sequence so as to ensure that the highway drainage facility is unblocked with the local agricultural irrigation facility. The longitudinal slope of the side ditch is not less than 0.3%, and the distance between water outlets is not more than 300m.

2, arranging transverse broken stone blind ditches at a filling transition section 21 with higher groundwater level of the roadbed for intercepting longitudinal slope seepage of the roadbed at the cutting section, wherein the blind ditches, the seepage ditches, the tubular seepage ditches, the intercepting water tubular seepage ditches and the like; the method is characterized in that a longitudinal broken stone blind ditch is arranged on a development section of rock mass fissure water of a side slope and used for cutting off transverse water seepage of the side slope, meanwhile, a blind ditch is arranged at a spring outlet dew point, underground water is led and discharged through the seepage ditch, and measures such as the blind ditch, the seepage ditch pipe type seepage ditch, the intercepting pipe type seepage ditch and the like are arranged on a rich section of the underground water, so that the underground water level is reduced and led and discharged out of a roadbed, and the stability of the roadbed is guaranteed.

3, when the final land after filling is still located at one side of the mountain, attention should be paid to the arrangement of drainage facilities. Besides the broken stone cushion layer arranged on the stratum, broken stone blind ditches are arranged on the surface of each backfill layer, the rainfall of the area and the catchment of the mountain are considered when the width and the height of the blind ditches are arranged, one end of each blind ditch is connected with the original mountain and is communicated with the catchment channel of the original mountain, and a reverse filtering layer is arranged at the outlet part.

The high-fill roadbed filling construction method adopts the filled stone embankment as the foundation, the embankment is paved with the geogrid, the roadbed is reinforced, the combined drainage system is utilized, and the safety and stability of the mountain highway high-fill embankment are improved. The filling embankment is a good embankment structure, and the filling of the filling embankment mainly originates from a large number of stone excavation and tunnel abandoning parties, and is preferably applied to a foundation part of embankment construction. The rock-filled embankment is adopted, so that the embankment can be reinforced to ensure the stability of the embankment, and the problem of underground water can be solved. The soft foundation is also subjected to an intensive treatment. The method also comprises settlement observation of the high-fill embankment, the settlement observation has important significance for the construction of the high-fill embankment, specific settlement indexes can be found in the construction to guide the next construction, meanwhile hidden dangers can be found early, serious quality accidents after traffic are avoided, the settlement observation points are required to be arranged at road centers and road shoulders at two sides according to actual conditions, each layer of observation is carried out once filling, and if the filling interval is longer for two times, each 3d of observation is carried out at least once. In the engineering of constructing the middle and high filled embankment, compensation compaction is further carried out, on-site compensation compaction is carried out by adopting impact compaction, the settlement rate of the embankment is accelerated, the integrity of the embankment is improved, and the settlement after construction is reduced. The application of the geogrid in the construction process of the high-fill roadbed can enable the stress of the embankment to be more uniform, enhance the bearing capacity of the embankment, have extremely strong tensile capacity, are not easy to damage, and are beneficial to stabilizing the whole roadbed.

The high-filling embankment can ensure engineering quality through roadbed substrate treatment, underground and ground drainage, embankment filling, roadbed reinforcement and application of corresponding auxiliary measures, has no problems of roadbed subsidence, slope sliding, cracking and the like, effectively prevents uneven settlement of high-filling roadbed, ensures that the roadbed consolidation rate reaches more than 99 percent, and basically completes roadbed settlement. The phenomena of pavement diseases such as pavement cracking, sinking and collapse caused by differential settlement are effectively controlled, so that the maintenance cost of mountain road maintenance is greatly reduced, the service life of the road is prolonged, better quality benefit can be obtained, meanwhile, the strength of the high-fill embankment and the filling junction can be obviously enhanced to control settlement, local materials are obtained, a large amount of materials and manpower are saved, and obvious economic and social benefits can be obtained.

Finally, it should be noted that: the above embodiments are only for illustrating the technical solution of the present application, and not for limiting the same; although the present application has been described in detail with reference to the foregoing embodiments, it should be understood by those of ordinary skill in the art that: the technical scheme described in the foregoing embodiments can be modified or some or all of the technical features thereof can be replaced by equivalents; such modifications and substitutions do not depart from the spirit of the corresponding technical solutions from the scope of the technical solutions of the embodiments of the present application.

Claims (10)

1. The high-fill roadbed filling construction method is characterized by comprising the following steps:

step 100, preparing work before construction;

step 200, compacting treatment of roadbed foundations before filling;

wherein, include: adopting excavation reverse steps at the filling and excavating juncture, and filling and compacting the steps; for the obvious sedimentation difference, adopting the rigid-flexible transition treatment from filling to digging, and arranging longitudinal and transverse blind ditches at the filling and digging juncture or filling water permeable material treatment; a transition section is arranged in the excavation section in the longitudinal direction of the filling and excavation joint part, and geogrid treatment is paved on the transition section;

step 300, roadbed filling;

step 400, filling stone roadbed, including base treatment, side slope stacking, layered filling and layered rolling;

step 500, reinforcing and compacting roadbed, namely performing rolling and reinforcing on high embankments with the height of the filled side slope being more than or equal to 20m and embankments with the height of the half-filled side slope being more than 8m by adopting impact rolling or a large-tonnage road roller;

step 600, mixing and filling soil and stones;

step 700, slope engineering, slope setting supporting and reinforcing engineering;

and 800, observing roadbed settlement, and monitoring stability of the embankment with the side slope height exceeding 20m or the embankment with the ground slope rate steeper than 1:2.5, and the embankment with the hidden danger of stability on the embankment by the foundation after half-filling the half-excavated embankment and the retaining wall section.

2. The high fill subgrade filling construction method as set forth in claim 1, wherein in step 200, the geogrid process comprises:

a transition section is arranged in the excavation section in the longitudinal direction of the joint of the filling and the excavation, the length of the transition section is 10m, and when the longitudinal or transverse gradient of a ground line is steeper than 1:2.5 and the height of a filling slope is greater than 8m, a geogrid with an interval of 30cm between one layer and two layers is paved from bottom to top at a position 150cm away from the road surface;

the geogrid adopts a production process of integral punching and stretching molding, and the width is not less than 5m; when the excavation area of the half-filled and half-excavated road section is soil or soft rock, a geogrid is paved in the area of the roadbed of the junction part of the filling and excavation.

3. The high fill subgrade filling construction method as set forth in claim 2, wherein said geogrid laying process further comprises:

the road embankment side slope height is more than or equal to 20m, two layers of geogrids are arranged below 2m from the road surface and are respectively arranged at the positions of 2m and 2.3m below 2m from the road surface;

and (3) reinforcing the roadbed by adopting a large-tonnage road roller for the high embankment with the filling side slope height of more than or equal to 20 m.

4. The method of high fill subgrade filling construction as set forth in claim 1, further comprising the step of treating a poor foundation in step 200, comprising:

For bad foundation treatment at a mountain depression paddy field: the method comprises the steps of (1) in a mountain depression paddy field section, performing surface soil moisture softening, ditching, intercepting, draining surface water and underground water before filling, performing pre-filling compaction and embankment filling after draining and airing; adding a water accumulation pit for a difficult drainage road section, regularly pumping water in the water accumulation pit, and compacting or changing and filling before filling; setting a broken stone blind ditch or a seepage ditch on a road section with spring eyes or rich groundwater; the water-permeable material is replaced or the sand cushion is arranged, the sand cushion is treated, the replacement depth is controlled within 3m, and the replacement depth of a local small-range area can be deepened;

for poor foundation treatment of pond sections: the subgrade passes through the pond section and is treated by cofferdam, water pumping, dredging and/or filling replacement, and the slope of the subgrade is paved or laid to be 0.5m above the normal water level;

for bad foundation treatment of abandoned land: firstly, removing impurities and filling soil or backfilling qualified roadbed filling after treatment.

5. The high fill subgrade filling construction method as set forth in claim 1, wherein in step 400, said base treatment comprises: removing the floating stones, plain fill and sub-clay layers on the ground surface to a fragment-shaped strongly differentiated rock stratum, wherein the floating stones are used as embankment filling materials after being disintegrated, and the transverse slope of the foundation is steeper than 1:5, digging the ground into steps with the width not less than 2.0m, and rolling the surface cleaned and the foundation after digging the steps by using a vibratory roller;

The side slope stacking comprises: the embankment slope protection adopts block stone stacking, adopts a process mode of filling first and then stacking, and adopts stacking protection;

the layered filling comprises: the embankment is filled layer by layer, the loose laying thickness of each layer of the lower embankment is smaller than 45cm, the loose laying thickness of each layer of the upper embankment is smaller than 35cm, each layer of filler is filled twice, coarse-grain stone is filled first, the thick loose laying thickness is 3/4, coarse-grain layers are flattened and stabilized by a bulldozer, a layer of stone chips or stone residues is filled, the thick loose laying thickness is 1/4, the consumption of the thick loose laying thickness accounts for 15% -20% of that of the coarse-grain stone, gaps among large-grain materials are filled, and the large-tonnage bulldozer is used for flattening and spreading materials;

the layering rolling comprises: pressing the two sides and then pressing the middle, longitudinally parallel to each other, stabilizing, and re-pressing for 6-8 times by using a road roller with large tonnage.

6. The method for filling and constructing the high-fill roadbed according to claim 5, wherein in the side slope stacking, each level of the embankment side slope is stacked in a step-type manner, and the stacking manner is as follows:

when the slope rate of the roadbed is 1:1.3, the width of the step is 26cm, and the height is 20cm;

when the slope rate of the roadbed is 1:1.5, the width of the step is 30cm, and the height is 20cm;

When the slope rate of the roadbed is 1:1.75, the width of the step is 35cm, and the height is 20cm.

7. The high fill subgrade filling construction method as set forth in claim 1, wherein in step 700, said slope engineering includes:

when the height of the embankment is more than 8M, grass-spreading slope protection is carried out on the side slope by adopting an arch-shaped skeleton of the embankment, an intermediate protecting channel is paved by adopting M7.5 slurry masonry or precast blocks, tree planting positions are reserved, and when the height of the embankment is less than or equal to 8M, grass-spreading protection is carried out on the side slope;

the side slope of the filled stone embankment adopts stacking protection, and the relation between the height of the filled stone embankment and stacking thickness is as follows: when the height of the roadbed is less than 5m, the thickness is more than or equal to 1m; when the height of the roadbed is more than or equal to 5m and less than or equal to 12m, the thickness is more than or equal to 1.5m; when the height of the roadbed is more than or equal to 12m, the thickness is more than or equal to 2m; when the landscape requirements exist, the greening protection design can be considered; the minimum size of the stacking stone blocks is not smaller than 300mm;

the roadbed surface drainage is carried out on the principle of reducing the interference to the original water system as much as possible, and the roadbed drainage is provided with a side ditch, a intercepting ditch, a drainage ditch and a rapid trough; the underground drainage facilities such as blind ditches, seepage ditches and inspection wells are arranged in the underground drainage of the roadbed.

8. The high-fill subgrade filling construction method as set forth in claim 1, wherein in step 800, the monitoring frequency of the subgrade settlement observation is:

Monitoring frequency, observing the embankment filling process once before filling a layer of soil, wherein the embankment filling lag period is shorter, the embankment filling lag period is longer, and the embankment filling lag period is observed once in one week; the embankment is filled to the period from the design elevation of the road groove to the pavement, and the embankment is observed once every half month or one month; after pavement is paved, observing every 3 months; the above detection frequency encrypts when it encounters a heavy rain.

9. The method of high fill subgrade filling construction as set forth in claim 1, further comprising step 900 after step 800, wherein the auxiliary measures include providing embankment side ditches, blind ditches, seepage ditches, tubular seepage ditches, cut-off tubular seepage ditches.

10. The method for filling and constructing a high-fill subgrade according to claim 8, wherein the embankment side ditch is connected with bridge and culvert in-out or cutting side ditches at two sides of the subgrade, the embankment side ditch adopts a serous rectangular side ditch, and when the embankment side ditch collides with a farmland drainage ditch, the ditch is changed and is connected with a water outlet of a drainage ditch or a culvert in sequence; the longitudinal slope of the side ditch is not less than 0.3%, and the distance between water outlets is not more than 300m;

a transverse broken stone blind ditch is arranged at a filling transition section of a roadbed, a longitudinal broken stone blind ditch is arranged at a side slope rock mass fissure water development section, a blind ditch is arranged at a spring opening dew point, underground water is led and discharged through a seepage ditch, and a blind ditch, a seepage ditch pipe type seepage ditch and a water interception pipe type seepage ditch are arranged at an underground water rich section;

When the final land after filling is still positioned at one side of the mountain, a drainage facility is arranged, besides a broken stone cushion layer arranged on the stratum, broken stone blind ditches are arranged on the surface of each backfill layer, one end of each blind ditch is connected with the original mountain, a water collecting channel of the original mountain is connected, and a reverse filtering layer is arranged at the outlet part.

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