CN202401363U - Flaky or blocky stone ventilated roadbed of expressway in frozen soil region - Google Patents

Flaky or blocky stone ventilated roadbed of expressway in frozen soil region Download PDF

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CN202401363U
CN202401363U CN 201120560303 CN201120560303U CN202401363U CN 202401363 U CN202401363 U CN 202401363U CN 201120560303 CN201120560303 CN 201120560303 CN 201120560303 U CN201120560303 U CN 201120560303U CN 202401363 U CN202401363 U CN 202401363U
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gravel
roadbed
layer
thickness
sheet piece
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汪双杰
章金钊
朱东鹏
刘戈
樊凯
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CCCC First Highway Consultants Co Ltd
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CCCC First Highway Consultants Co Ltd
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Abstract

The utility model relates to a flaky or blocky stone ventilated roadbed of an expressway in a frozen soil region. Safety and service life of projects are seriously affected by longitudinal cracking of the frozen soil roadbed due to hot melting settlement, size effect of the roadbed under an asphalt pavement and the like. A gravel underlying layer with the thickness of 30 centimeters is impacted, rolled and constructed on the base of a soil arch, the gravel underlying layer is impacted and rolled under a ground line, a flaky or blocky stone layer with the thickness of 0.9 to 1.5 meters is constructed on the gravel underlying layer, the upper part of the flaky or blocky stone layer is flattened by using a macadam transition layer with the thickness of 20 centimeters, a gravel overlay layer with the thickness of 30 centimeters is constructed on the macadam transition layer, permeable geotextile is paved between the gravel overlay layer and the macadam transition layer, a geogrid made of glass-reinforced plastics is paved on the gravel overlay layer, and the layers are compacted by a heavy-duty vibrating road roller. Melting of the ever-frozen soil roadbed and non-uniform deformation of the frozen soil roadbed can be reduced, influence of climate warming and human engineering activities on properties of the ever-frozen soil roadbed is reduced, and the safety and the stability of the roadbed structure are improved.

Description

A kind of permafrost region speedway sheet piece stone ventilated embankment
Technical field
The utility model belongs to the traffic engineering technical field, is specifically related to a kind of permafrost region speedway sheet piece stone ventilated embankment.
Background technology
Frozen soil is as a kind of special soil body, and its composition, group structure, hot physics and physico-mechanical properties all are different from the general soil body.Seasonal freezing and thawing are all taking place in every year in the mobile layer of permafrost region, and association has various frozen soil phenomenons, have brought an a series of engineering difficult problem therefore for the constructing highway technology of permafrost region.At present; Under the background of intensification and human activity effect enhancing; Ever-frozen ground response manifests gradually, and it is unusual complicated and have polytropy that ever-frozen ground district frozen soil engineering geology becomes, and typical problem such as frozen earth roadbed hot thaw collapse fall into, frozen soils temperature field anisotropy causes roadbed dimensional effect or the like under roadbed longitudinal cracking that the asymmetric variation of the artificial upper limit causes, the flexible pavement under the roadbed; This has not only improved construction engineering cost greatly, and has a strong impact on the result of use and the life-span of engineering.
The utility model content
The purpose of the utility model provides a kind of permafrost region speedway sheet piece stone ventilated embankment that can effectively alleviate ever-frozen ground thawing and frozen earth roadbed inhomogeneous deformation.
The technical scheme that the utility model adopted is:
A kind of permafrost region speedway sheet piece stone ventilated embankment is characterized in that:
Described permafrost region speedway sheet piece stone ventilated embankment is followed successively by bed course and GSZ on gravel underlayer, sheet block stone layer, rubble transition zone, permeable geotextiles, the gravel from bottom to top;
Wherein gravel underlayer part impact-rolling is below above-ground route.
The thickness of described gravel underlayer is 30cm;
The thickness of described block stone layer is 0.9m~1.5m;
The thickness of described rubble transition zone is 20cm;
The thickness of bed course is 30cm on the described gravel.
The sheet piece stone particle diameter of described block stone layer is 15~30cm, and slenderness ratio is less than 3, and sheet piece stone intensity is greater than 30MPa, and void content is not less than 25%;
The ballast grain sizes of described rubble transition zone is 5~10cm.
One side of described permafrost region speedway sheet piece stone ventilated embankment is provided with the banket of level, banket arranged outside gutter.
The utlity model has following advantage:
Described piece stone of the utility model ventilated embankment structure utilizes flowing of air to change the roadbed heat transfer type; Can reduce that frozen soil under the subgrade in permafrost soil zone melts and the inhomogeneous deformation of frozen earth roadbed generation; Reduce climate warming and of the influence of artificial engineering activity, improve the safety and the stability of road structure the subgrade in permafrost soil zone characteristic.
Description of drawings
Fig. 1 is the structure chart of sheet piece stone ventilated embankment.
Fig. 2 is sheet piece stone ventilated embankment construction process figure.
Among the figure, the 1-GSZ, bed course on the 2-gravel, the permeable geotextiles of 3-, 4-rubble transition zone, 5-gravel underlayer, the 6-above-ground route, the 7-banket, the 8-gutter, 9-sheet block stone layer, 10-bankets, 11-soil arch.
The specific embodiment
Below in conjunction with the specific embodiment the utility model is carried out detailed explanation.
Sheet piece stone road structure is the engineering measure of a most typical cooling roadbed, is to utilize flowing of air to change a kind of ventilated embankment of roadbed heat transfer type, and air can flow in roadbed sheet block stone layer.Under open state, be that the recombination process of main forced convection effect and more weak sheet block stone layer side direction air free convection is the mechanism of action of sheet piece stone cooling roadbed winter with the draught effect, and this recombination process is main relevant with wind speed and direction.When wind speed is big, produce the forced ventilation effect in the sheet block stone layer; But wind speed hour, in Schattenseite lateral plate block stone layer certain thickness, produces free convection effect.Summer, the sheet block stone layer was main with heat transfer process mainly because of the wind speed and direction condition, but summer, the wind speed and direction condition helped the certain heat-blocking action of the inner generation of sheet piece stone structure layer.Under closed state, because blocking-up or significantly weakened the influence of wind, the sheet block stone layer road structure forced convection process that weakened; Simultaneously because the influence of banketing in sheet block stone layer roadbed top; The sheet block stone layer roof and floor temperature difference is not enough to drive the free convection process; Therefore, sheet block stone layer inside is main with heat transfer process mainly under closed state, and the effect of certain heat-insulation and heat-preservation has been played in the space in the sheet block stone layer.
The described permafrost region speedway of the utility model sheet piece stone ventilated embankment is followed successively by bed course 2 and plastic-steel geotechnical grid 1 on gravel underlayer 5, sheet block stone layer 9, rubble transition zone 4, permeable geotextiles 3, the gravel from bottom to top, and wherein gravel underlayer 5 part impact-rollings are below above-ground route.The thickness of gravel underlayer 5 is 30cm; The thickness of sheet block stone layer 9 is 0.9m~1.5m; The thickness of rubble transition zone 4 is 20cm; The thickness of bed course 2 is 30cm on the gravel.The sheet piece stone particle diameter of sheet block stone layer 9 is 15~30cm, and slenderness ratio is less than 3, and sheet piece stone intensity is greater than 30MPa, and void content is not less than 25%; The ballast grain sizes of rubble transition zone 4 is 5~10cm.One side of permafrost region speedway sheet piece stone ventilated embankment is provided with the banket 7 of level, banket 7 arranged outside gutters 8.
According to the heat conduction of sheet piece stone roadbed, forced-convection heat transfer and these three kinds of mechanism of heat transfer free convection, satisfying under the prerequisite of mechanics, the making thickness of sheet block stone layer 9 is preferably 0.9~1.5m.Consider that from the angle of strengthening free convection heat transfer mechanism the position that sheet block stone layer 9 is laid should satisfied under the prerequisite of mechanics in embankment, lean on roadbed top as far as possible, to reduce the thickness of going up overburden layer; But consider to the efficient of ground transmission from cold, should be near the bottom of roadbed body.In the middle of concrete design, should take all factors into consideration the factor aspect two, sheet block stone layer 9 is being laid in the optimum position of roadbed body, be generally the following 30~50cm of road surface structare layer.Collateral security sheet piece stone roadbed reaches the void content and the sheet piece stone space of design and can consider with the good UNICOM of atmosphere two aspects; Be recommended in sheet block stone layer bottom and lay gravel underlayer 5; Bed course 2 on permeable geotextiles 3 and the gravel is laid at the top, and the thickness of bed course 2 is generally 30cm on gravel underlayer 5 and the gravel.
Embodiment one:
The ice-rich permafrost section; When roadbed height during greater than 2.5m and less than 2.8m; At the substrate impact-rolling and the gravel underlayer 5 that fills 30cm of soil arch, gravel underlayer 5 part impact-rollings fill the thick sheet block stone layer 9 of 0.9m above gravel underlayer 5 below above-ground route; Sheet block stone layer 9 tops are with thick rubble transition zone 4 levelings of 20cm; Fill bed course 2 on the thick gravel of 30cm on it again, 4 of bed course 2 and rubble transition zones are laid permeable geotextiles 3 on the gravel, and the GSZ 1 of plastic-steel material is laid on bed course 2 tops on the gravel.
Embodiment two:
The ice-rich permafrost section; When roadbed height during greater than 2.8m; At the substrate impact-rolling and the gravel underlayer 5 that fills 30cm of soil arch, gravel underlayer 5 part impact-rollings fill the thick sheet block stone layer 9 of 1.2m above gravel underlayer 5 below above-ground route; Sheet block stone layer 9 tops are with thick rubble transition zone 4 levelings of 20cm; Fill bed course 2 on the thick gravel of 30cm on it again, 4 of bed course 2 and rubble transition zones are laid permeable geotextiles 3 on the gravel, and the GSZ 1 of plastic-steel material is laid on bed course 2 tops on the gravel.
Embodiment three:
Full freezing soil section; When roadbed height during greater than 2.5m and less than 3.1m; At the substrate impact-rolling and the gravel underlayer 5 that fills 30cm of soil arch, gravel underlayer 5 part impact-rollings fill the thick sheet block stone layer 9 of 0.9m above gravel underlayer 5 below above-ground route; Sheet block stone layer 9 tops are with thick rubble transition zone 4 levelings of 20cm; Fill bed course 2 on the thick gravel of 30cm on it again, 4 of bed course 2 and rubble transition zones are laid permeable geotextiles 3 on the gravel, and the GSZ 1 of plastic-steel material is laid on bed course 2 tops on the gravel.
Embodiment four:
Full freezing soil section; When roadbed height during greater than 3.1m; At the substrate impact-rolling and the gravel underlayer 5 that fills 30cm of soil arch, gravel underlayer 5 part impact-rollings fill the thick sheet block stone layer 9 of 1.5m above gravel underlayer 5 below above-ground route; Sheet block stone layer 9 tops are with thick rubble transition zone 4 levelings of 20cm; Fill bed course 2 on the thick gravel of 30cm on it again, 4 of bed course 2 and rubble transition zones are laid permeable geotextiles 3 on the gravel, and the GSZ 1 of plastic-steel material is laid on bed course 2 tops on the gravel.
The job practices of the described permafrost region speedway of the utility model sheet piece stone ventilated embankment, realized by following steps:
Step 1: measure unwrapping wire according to construction design drawing, mark the sideline of route, fill scope.Carry out permanent and interim work such as draining.Prepare construction machinery, transportation, loading and unloading, leveling, each operation of compacting of guaranteeing to satisfy material closely are connected, and form continuous processing line.The method of the full section construction of employing full width in the assurance subgrade construction must design build guarantor excrement channel to the logical highway section of highway that requires of guarantor is arranged, and public vehicles must not pass through before the roadbed unshaped.
Step 2: building stones require clean, no weathering, scale, crackle, and anti-freezing, no grating, undesirable building stones must not get into the job site, and qualified building stones are carried out fragmentation by the requirement to particle diameter in the design document.Screen after the fragmentation again, painstakingly do not select single particle size, adhering to specification gets final product, and undesirable small crushed stone as the levelling filler on the sheet block stone layer, is utilized to greatest extent, reduces discarded amount.Carry out the broken screening of building stones, the sheet piece stone particle diameter of sheet block stone layer 9 is 15~30cm, and slenderness ratio is less than 3, and sheet piece stone intensity is greater than 30MPa, and void content is not less than 25%; The ballast grain sizes of rubble transition zone 4 is 5~10cm.
Step 3: filling one deck soil arch 11 on ground, from the roadbed center is 2% draining horizontal wall inscription to the peripheral hardware gradient, and soil arch 11 was one-way slope when ground was the slope, and soil arch 11 was open roof when ground was flat slope.Toe place lift thickness ≮ 0.3 m, compactness is by the following filler requirement control of bedding, and planeness is controlled by the roadbed requirement.
Step 4: at the substrate impact-rolling and the gravel underlayer 5 that fills 30cm of soil arch; Gravel underlayer 5 part impact-rollings are below above-ground route; Above gravel underlayer 5, fill the thick sheet block stone layer 9 of 0.9m~1.5m; Bed course 2 on the thick gravel of 30cm is filled again with thick rubble transition zone 4 levelings of 20cm in sheet block stone layer 9 tops on it, 4 of bed course 2 and rubble transition zones are laid permeable geotextiles 3 on the gravel; The GSZ 1 of plastic-steel material is laid on bed course 2 tops on the gravel, adopts heavy vibratory roller compacting at last.Sheet piece stone roadbed side slope carries out necessary protection, and guarantees that roadbed both sides draining is smooth and easy and do not produce alluvial.
Fill the embankment formula of inclining that adopts, self-unloading truck, bulldozer, excavator cooperate and carry out operation, and once fill design height, and side slope adopts the artificial sign indicating number of sheet piece stone to build, and building stones are with the machinery leveling, and indivedual positions are artificial uses the finger stone levelling.Must not damage the limit portion building stones of sign indicating number block when feeding intake, will in time repair for what damage.Take low earlier back high during filler, the feeding mode of two rear flank central authorities carries out earlier.
Heavy vibratory roller is adopted in the compacting of sheet piece stone roadbed, in the middle of straight line highway section elder generation two rear flank, and the outside, the earlier interior rear flank of curved section; Roll repeatedly; Number of rolling is no less than 6~8 times, and overlapping 0.5m between vertical row that rolls and the row is more than the overlapping 2m of front and back adjacent sections.Compacting should be even, by designing requirement control compactness, guarantees its planeness and stability.The linear pressure of road roller should be complementary with the compressive strength limit of slabstone, avoids making the broken and squeeze and destroy cage construction of slabstone.
The linear pressure of road roller is meant its unit line load, and for sheet piece stone, its compressive strength limit can only allow certain linear pressure, otherwise fragmentation and extruding can appear in sheet piece stone, destroys cage construction.The compressive strength limit of several kinds of building stones commonly used and the linear load of permission are seen table 1.
The compressive strength limit of several kinds of building stones of table 1
Figure 2011205603030100002DEST_PATH_IMAGE002
The unit line LOAD FOR formula of road roller is:
q=G/b
Q one unit line load (N/cm);
The steel wheel of G one vibratory roller heavy (N);
B one takes turns wide (cm)
For avoiding sheet piece stone surface because of the static pressure of being born causes the top layer to destroy greater than its compressive strength, crackle occurs or press unreal phenomenon, the maximum contact stress of selected road roller must meet the permissible value of sheet piece stone, sees table 2.
Generally bringing formula into by unit line load calculates:
Figure 2011205603030100002DEST_PATH_IMAGE004
The maximum contact stress (MPa) of
Figure DEST_PATH_IMAGE006
-permission;
Q one unit line load (N/m);
The modulus of deformation (MPa) of
Figure DEST_PATH_IMAGE008
-compacted lift;
R-rolling wheel radius (m).
Table 2 a piece stone allows maximum contact stress
Figure DEST_PATH_IMAGE010
Geotextiles unavoidably can receive the effect of external force in construction and in the operating period, therefore, require it to have certain intensity.The geotextiles performance indications that contrast China produces, the product of most of producer are worked as mass area ratio and are reached 300g/m 2~500g/m 2The time, can satisfy requirement in the table.Comparison film piece stone roadbed geotextiles environmental aspect of living in, the geotextiles performance indications adopt 1 grade in the table 3, mass area ratio 350 g/m 2
Table 3 geotextiles performance indications
Figure DEST_PATH_IMAGE012
With the geotextiles horizontal positioned, when getting rid of the fixed current of foundation soil or other current, require its drainability qc to be not less than the discharge q that must discharge, promptly satisfy the requirement of formula (1-1).
qc?≥?q (1-1)
In the formula: the discharge butene-1 copolymer ㎡ that q-vertical water seepage direction, every linear meter(lin.m.) need discharge/s);
The drainability of qc-every linear meter(lin.m.) of geotextiles water outlet section is calculated by formula (1-2)
qc?=?
Figure DEST_PATH_IMAGE014
(1-2)
Figure 164558DEST_PATH_IMAGE016
In the formula: the laying mode coefficient of β-geotextiles, the width of laying on promptly every linear meter(lin.m.), when completely spreading, β=1; When being strip-type.β=(Σ Bi)/1.0, (Σ Bi) is the summation of strip width on every linear meter(lin.m.);
The hydraulic conductivity of θ-geosynthetics (m3/s) should carry out flushing test according to actual pressurized situation and measure;
L-water (flow) direction geosynthetics length (m);
Δ h-along the first terminal head difference (m) of drainage blanket length L;
The safety stock coefficient that F-consideration is become silted up and blocked up is got Fd=10, when having ready conditions, can be confirmed by the ratio of the stifled front and back hydraulic conductivity that becomes silted up according to result of the test.

Claims (4)

1. permafrost region speedway sheet piece stone ventilated embankment is characterized in that:
Described permafrost region speedway sheet piece stone ventilated embankment is followed successively by bed course (2) and GSZ (1) on gravel underlayer (5), sheet block stone layer (9), rubble transition zone (4), permeable geotextiles (3), the gravel from bottom to top;
Wherein gravel underlayer (5) part impact-rolling is below above-ground route.
2. a kind of permafrost region speedway sheet piece stone ventilated embankment according to claim 1 is characterized in that:
The thickness of described gravel underlayer (5) is 30cm;
The thickness of described block stone layer (9) is 0.9m~1.5m;
The thickness of described rubble transition zone (4) is 20cm;
The thickness of bed course on the described gravel (2) is 30cm.
3. a kind of permafrost region speedway sheet piece stone ventilated embankment according to claim 1 and 2 is characterized in that:
The sheet piece stone particle diameter of described block stone layer (9) is 15~30cm, and slenderness ratio is less than 3, and sheet piece stone intensity is greater than 30MPa, and void content is not less than 25%;
The ballast grain sizes of described rubble transition zone (4) is 5~10cm.
4. a kind of permafrost region speedway sheet piece stone ventilated embankment according to claim 3 is characterized in that:
One side of described permafrost region speedway sheet piece stone ventilated embankment is provided with the banket (7) of level, banket (7) arranged outside gutter (8).
CN 201120560303 2011-12-29 2011-12-29 Flaky or blocky stone ventilated roadbed of expressway in frozen soil region Expired - Fee Related CN202401363U (en)

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Cited By (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN102433814A (en) * 2011-12-29 2012-05-02 中交第一公路勘察设计研究院有限公司 Permafrost region expressway flaky and blocky stone ventilation roadbed and construction method thereof
CN103510441A (en) * 2013-10-16 2014-01-15 江苏省镇江市路桥工程总公司 Three-dimensional-drainage roadbed structure for preventing water damage of road in cold region and construction method thereof
CN105297572A (en) * 2015-10-10 2016-02-03 青海省交通科学研究院 Permafrost fill construction method

Cited By (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN102433814A (en) * 2011-12-29 2012-05-02 中交第一公路勘察设计研究院有限公司 Permafrost region expressway flaky and blocky stone ventilation roadbed and construction method thereof
CN103510441A (en) * 2013-10-16 2014-01-15 江苏省镇江市路桥工程总公司 Three-dimensional-drainage roadbed structure for preventing water damage of road in cold region and construction method thereof
CN103510441B (en) * 2013-10-16 2015-06-17 江苏省镇江市路桥工程总公司 Three-dimensional-drainage roadbed structure for preventing water damage of road in cold region and construction method thereof
CN105297572A (en) * 2015-10-10 2016-02-03 青海省交通科学研究院 Permafrost fill construction method

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