TB 10001-2016 (TB10001-2016)

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TB 10001-2016: PDF in English
TB 10001-2016
INDUSTRY STANDARD OF THE
PEOPLE’S REPUBLIC OF CHINA
UDC
P TB 10001-2016
J 447-2017
Code for design of railway earth structure
ISSUED ON: DECEMBER 20, 2016
IMPLEMENTED ON: APRIL 01, 2017
Issued by: State Railway Administration
Table of Contents
Foreword ... 8 
1 General ... 11 
2 Terms and symbols ... 12 
2.1 Terms ... 12 
2.2 Symbols ... 16 
3 Basic requirements ... 17 
3.1 Elevation of subgrade shoulder ... 17 
3.2 Shape and width of formation surface ... 19 
3.3 Subgrade stability and settlement control criteria ... 29 
3.4 Deformation observation and evaluation ... 36 
3.5 Design service life ... 37 
4 Design load ... 37 
4.1 General provisions ... 37 
4.2 Main force ... 39 
4.3 Additional force ... 47 
4.4 Special forces ... 48 
5 Engineering materials ... 48 
5.1 General provisions ... 48 
5.2 Filler ... 48 
5.3 Stone ... 54 
5.4 Concrete ... 55 
5.5 Cement mortar ... 56 
5.6 Steel ... 58 
5.7 Geosynthetics ... 59 
6 Subgrade bed ... 62 
6.1 General provisions ... 62 
6.2 Subgrade bed structure ... 62 
6.3 Embankment subgrade bed ... 64 
6.4 Subgrade bed for cutting ... 65 
6.5 Compaction criteria of subgrade bed ... 66 
6.6 Treatment measures of subgrade bed ... 68 
7 Embankment ... 68 
7.1 General provisions ... 68 
7.2 Filler and filling requirements ... 69 
7.3 Compaction criteria ... 70 
7.4 Slope form and slope rate ... 72 
8 Cutting ... 73 
8.1 General provisions ... 73 
8.2 Soil cuttings ... 73 
8.3 Rock cutting... 74 
9 Transition section ... 75 
9.1 General provision ... 75 
9.2 Transition section between subgrade and abutment ... 76 
9.3 Transition section between subgrade and lateral structure ... 78 
9.4 Transition section between embankment and cutting ... 80 
9.5 Transition section between cutting and tunnel ... 81 
10 Ground treatment ... 82 
10.1 General provisions ... 82 
10.2 Main technical requirements ... 83 
10.3 Common measures ... 85 
11 Retaining structure ... 86 
11.1 General provisions ... 86 
11.2 Main design principles ... 87 
11.3 Types of common retaining structure and scope of application ... 89 
12 Subgrade protection ... 90 
12.1 General provisions ... 90 
12.2 Plant protection ... 90 
12.3 Skeleton protection ... 91 
12.4 Physical slope protection (wall) ... 92 
12.5 Hole-window slope protection (wall) ... 93 
12.6 Anchor framed girder slope protection ... 93 
12.7 Shotcrete (mortar) slope protection ... 94 
12.8 Gabion protection ... 94 
12.9 Protection net ... 95 
12.10 Geosynthetics protection ... 95 
12.11 Subgrade plane protection in wind and sand and snow damage areas ... 96 
12.12 Thermal insulation of subgrade ... 98 
13 Water prevention and drainage of subgrade ... 99 
13.1 General provisions ... 99 
13.2 Surface water ... 100 
13.3 Groundwater ... 104 
14 Reconstruction of railway subgrade for existing line and addition of second
line ... 108 
14.1 General provisions ... 108 
14.2 Reconstruction of subgrade of existing line ... 110 
14.3 Addition of subgrade for a second line ... 113 
14.4 Reconstruction, reinforcement, utilization of existing structures ... 114 
15 Borrow (spoil) area and earthwork allocation ... 115 
15.1 General provisions ... 115 
15.2 Borrow area ... 116 
15.3 Spoil area (heap) ... 116 
15.4 Reclamation and protection of borrow (spoil) area ... 117 
15.5 Earthwork allocation ... 118 
16 Subgrade interface design ... 118 
16.1 General provisions ... 118 
16.2 Safety protection facilities ... 119 
16.3 Cable trough ... 120 
16.4 Others ... 120 
Appendix A Grouping classification of ordinary fillers ... 121 
Appendix B Design of improved soil and test requirements ... 131 
Appendix C Steel model, concrete grade and strength ... 137 
Appendix D Common ground treatment methods and measure application
conditions ... 140 
Appendix E Green protection for subgrade slopes ... 142 
Appendix F Diagrams for design of subgrade waterproof and drainage ... 144 
Explanation of wording in this code ... 150 
Code for design of railway earth structure
1 General
1.0.1 This code is formulated to unify the technical standards for railway
subgrade design, make the subgrade design meets the requirements of safety,
reliability, advanced technology, economic rationality.
1.0.2 This code is applicable to the design of standard gauge subgrades for
high-speed railways, intercity railways, passenger-freight level I and level II
railways, heavy-duty railways.
1.0.3 The subgrade project shall be designed according to the geotechnical
structure, to ensure that it meets the requirements of strength, stability and
durability; meets the relevant requirements of environmental protection, soil and
water conservation, cultural relic protection, etc.
1.0.4 The subgrade engineering shall, through geological mapping,
comprehensive exploration, testing and analysis, ascertain the geotechnical
structure and physical and mechanical properties of the subgrade base, cutting
slope, retaining structure foundation, etc., as well as the nature and distribution
of the filler. Perform design based on reliable geological data.
1.0.5 The subgrade engineering design should avoid high filling, deep
excavation, long cutting; avoid areas with adverse geological conditions. In the
comparison and selection of subgrade, bridge, tunnel engineering, it shall make
comprehensive analysis in terms of technical conditions, construction
conditions, land occupation, possible environmental and social impacts, urban
construction planning, construction investment, operation and maintenance
costs, to determine the type of project.
1.0.6 The railway train’s load shall be determined according to railway
transportation characteristics, mobile equipment, design speed, etc. High-
speed railway should adopt ZK load diagram. Intercity railway should adopt ZC
load diagram. Passenger-freight railways should adopt ZKH load diagram.
Heavy-load railway should use ZH load diagram. When the characteristics of
passenger-freight railway meet the standards of heavy-duty railways, it shall
use the ZH load diagram.
1.0.7 The design of subgrade engineering shall be based on railway grade,
subgrade structure, and other factors; according to local conditions, reasonably
select engineering materials. Meanwhile it shall meet the application conditions
and use requirements of subgrade engineering. Subgrade fillers shall be
A geotechnical structure directly supporting the track structure formed by
excavation or filling.
2.1.2 Embankment
Subgrade filled with soil and stone on the ground.
2.1.3 Cutting
Subgrade dug down from the ground surface.
2.1.4 Subgrade shoulder
The part at both sides of the formation surface which is not covered by the
ballast bed.
2.1.5 Elevation of subgrade shoulder
The elevation of the outer edge of the shoulder.
2.1.6 Width of formation surface
The horizontal distance between the outer edges of the subgrade shoulders on
both sides of the formation surface.
2.1.7 Subgrade bed
Subgrade superstructure below the elevation of subgrade that is significantly
affected by train loads. The subgrade bed consists of a surface layer and a
bottom layer.
2.1.8 Lateral structure
A collective term of such structures as culverts, frame bridges, rigid-frame
bridges (steel-structure bridges) which cross the railway subgrade.
2.1.9 Transition section
The section at the joint between the subgrade and bridge abutments, lateral
structures, tunnels, embankments and cutting, which needs special treatment.
2.1.10 Post-construction settlement of subgrade
Settlement of the subgrade after the completion of the track laying project.
2.1.11 Settlement evaluation
According to the settlement observation data, combined with the geological
conditions and ground treatment measures, the process of comprehensively
2.1.20 Permeable soil
Giant grain soil and coarse grain soil (except fine sand) which has fine grain
soil content of less than 10% and permeability coefficient greater than 1 x 10-5
m/s.
2.1.21 Geosynthetics
A general term for various types of materials based on synthetic polymers used
in civil engineering.
2.1.22 Optimum moisture content
The moisture content corresponding to the peak point on the relationship curve
between the dry density and the moisture content obtained by the compaction
test.
2.1.23 Ground treatment
Technical measures taken to improve the bearing capacity of the foundation
and improve its deformation or permeability.
2.1.24 Granular column composite foundation
Composite foundation which uses sand piles, sand gravel piles and gravel piles
for vertical reinforcement.
2.1.25 Flexible pile composite foundation
Composite foundation which uses flexible pile for vertical reinforcement.
2.1.26 Rigid pile composite foundation
Composite foundation which uses friction-type rigid pile for vertical
reinforcement.
2.1.27 Retaining structure
Structures which support the lateral earth pressure or resistance to soil sliding.
2.1.2 Stability factor of slope
In slope stability analysis, the ratio of the sliding force (moment) of the soil along
a sliding surface to the sliding force (moment).
2.1.29 Revetment, slope protection
Protective engineering for preventing weathering, peeling, slipping, scouring of
the roadbed slope (gentle than 1:1.0).
addition of the second line shall be determined at the feasibility study
stage based on years of operation and water disaster.
3.1.2 The elevation of the shoulders of riverbanks and bench land
embankments shall be greater than the sum of the designed flood level, the
height of the backwater (including backwater caused by the opening of the river
or the building, the super-high water level of the river bay), the high wave
invasion or the partial flush of the oblique flow, the height due to riverbed
deposition, the safe height. Among them, it shall take the larger of the wave
invasion height and the oblique current partial upsurge.
3.1.3 The height of the shoulder of the reservoir subgrade shall be greater than
the sum of the design water level, wave invasion height, backwater height
(including the backwater of the reservoir and the backwater on the shore), the
safe height. When the design water level calculated according to the prescribed
flood frequency is lower than the normal high-water level of the reservoir, use
the normal high-water level of the reservoir as the design water level.
3.1.4 For coastal embankments, when no wave barrier wall is provided on the
top, the elevation of shoulder shall be greater than the sum of the designed tidal
water level, wave invasion height (wave climbing height), safe height, etc.;
when a wave barrier wall is provided, the elevation of shoulder shall be greater
than sum of design high tidal level and safe height.
3.1.5 For the subgrade of the higher groundwater level or groundwater area,
the elevation of shoulder shall be greater than the sum of the highest
groundwater level or the highest ground area water level, the strong rise of
capillary water, the safe height.
3.1.6 The elevation of the shoulder of the subgrade in the seasonal frozen soil
area shall be greater than the sum of the groundwater level before freezing or
the surface water level before freezing, the strong rise of capillary water, the
depth of harmful frost heave, the safe height.
3.1.7 The elevation of the shoulder of the saline soil subgrade shall be greater
than the sum of the highest groundwater level or the highest surface area water
level, the strong rise of capillary water, the depth of strong influence of
evaporation, the safe height. When there is seasonal freezing damage to the
saline soil subgrade, the elevation of shoulder shall be calculated separately
according to the provisions of clause 3.1.6 of this code and this clause,
whichever is greater.
3.1.8 When the subgrade adopts measures such as lowering the water level
and setting capillary water partitions, the elevation of the shoulder may not be
subject to the restrictions specified in clause 3.1.5 to 3.1.7 of this code.
3.1.9 The safe height in clauses 3.1.2 ~ 3.1.7 of this code should be 0.5 m.
mXs - The empirical correction factor for the settlement of the underlying layer,
which is related to the foundation conditions, load strength, loading rate, etc.;
S2 - Calculated value of the settlement of the underlying layer (m).
3.3.9 The calculation of foundation settlement shall meet the following
requirements:
1 The calculated depth of the compression layer of the high-speed railway
and ballast-less track’s foundation is determined by the additional stress
which is 0.1 times the self-weight stress; the calculated depth of the
compression layer of the other railway’s foundations is determined by the
additional stress which is 0.2 times the self-weight.
2 If there is still a soft soil layer below the calculated depth, it shall
continuously increase the calculated depth.
3 In the calculation of the settlement of the double track foundation, the track
load can be designed as a double line; the train load should be designed
as a single line.
3.4 Deformation observation and evaluation
3.4.1 Subgrade of high-speed railway and ballast-less track railway shall be
subjected to settlement evaluation. The heavy-load railway, ballasted track
railway with design speed of 200 km/h and in such sections as in soft soil and
collapsible loess should be subject to foundation settlement evaluation.
3.4.2 Subgrade deformation observation shall focus on the observation of
formation surface settlement and foundation settlement. During the filling period
of the embankment of the soft soil section, it shall also observe the horizontal
displacement of the slope foot of the subgrade, control the filling rate, ensure
the subgrade stability.
3.4.3 The layout of deformation observation sections and observation facilities
shall be comprehensively determined based on topographic and geological
conditions, ground treatment methods, subgrade types, embankment heights
and other factors in combination with the construction period. The distance
between observation sections should be 50 m ~ 100 m.
3.4.4 Deformation observation methods and accuracy shall meet the
requirements of relevant railway standards of different grades. Subgrade shall
be continuously observed after the start of construction. After finishing the
subgrade filling or applying the preload, the settlement observation time should
be not less than 6 months. If the observation data is insufficient to evaluate or
the post-construction settlement assessment cannot meet the requirements, it
4 When the slope surface is protected by mortar spray, the strength grade of
cement mortar should not be lower than M10.
5.6 Steel
5.6.1 The steel for subgrade work any use the reinforcing steel bars,
prestressed steel wire, steel strand, steel plate and section steel. The strength
of reinforcing steel bars, prestressed steel wires, strands shall be determined
according to their models in accordance with Appendix C.
5.6.2 Ordinary steel bars and prestressed steel bars shall be selected according
to the following requirements:
1 The longitudinally stressed steel bars for the retaining and bearing
reinforced concrete structure should use HRB400 and HRB500 steel bars;
it may also use HPB300 steel bars. The stirrups should use the HPB 300,
HRB400, HRB500 steel bars.
2 Tensioned anchors for anchor retaining wall and soil nailed wall structures
should use ribbed steel bars, prestressed threaded steel bars; it should
not use galvanized steel and the diameter should not be less than 16 mm.
The vertically prestressed anchor retaining walls and other structural
prestressed anchors should use cold-drawn steel bars.
3 Structurally tensioned anchors such as slope hanging net protection or
framed girder slope protection should use HRB400 and HRB500 steel
bars, the diameter of which should not be less than 16 mm.
5.6.3 Prestressed anchor rods should use prestressed threaded rebar;
prestressed anchor cables should use high-strength low-relaxation prestressed
steel strands; the diameter of steel strands may use Φ12.7 mm or Φ15.2 mm.
5.6.4 Steels such as steel plates, sections, bolts and anchors shall meet the
following requirements:
1 Steel plates are divided into U-shaped, Z-shaped, S-shaped, linear and
other types; section steel is divided into I-shaped steel, channel steel,
angle steel, round steel and other types.
2 The temporary supporting for small-scale foundation pits and slope
excavation may use steel plates, I-beams or channel steels, or waste steel
rails.
3 The dimensions of anchor plate’s tie rods, anchor retaining wall’s anchor
rods, pre-stressed anchor rod’s end fixed steel backing plates shall meet
the requirements for calculation of local bearing strength.
1 The water isolation anti-seepage layer of the Newly built railway subgrade
bed water-proof and anti-seepage layer, and embankment base capillary
water insulation cushion layer, it is advisable to use water-tight
geomembrane, composite geomembrane, capillary or composite water-
proof drainage board, etc. The frost-resistant area should meet the frost
resistance requirements; when used for capillary water partition, it shall
have long-term corrosion resistance and aging resistance to sulfate,
chloride, carbonate.
2 When the existing subgrade bed’s strength is insufficient, or such defects
as subsidence, sinking, water accumulation and so on are treated, it may
use the geotechnical cells for reinforcement and seepage pipes or
drainage boards to lead and drain water.
3 The subgrade bed in the freezing disaster area may adopt polystyrene or
polyurethane foam insulation layer; its performance indicators such as
apparent density, compressive strength, thermal conductivity, water
absorption shall meet the design requirements.
4 The lateral drainage cushion layer on the embankment base, slope
protection, protection wall, retaining wall or anti-filtration layer after
intercepting drainage ditch, seepage ditch, blind drain of intercepting ditch,
back anti-filtration layer of blind drain, anti-filtration layer between fillers of
different grain sizes may use non-woven geotextile or its wrap of gravel
and macadam as the anti-filtration material. The soil retention, water
permeability, anti-blocking index, puncture strength of the non-woven
geotextile shall meet the design requirements.
5 For drainage of groundwater, it may use seepage pipes or geotextiles and
wrap of gravel and macadam for filtration and drainage.
6 The water seepage pipe shall have good water permeability, filtration,
longitudinal drainage performance; it shall have the characteristics of high
ring stiffness, chemical resistance, long life and so on.
5.7.5 When geosynthetics are used for subgrade slope protection, it shall meet
the following requirements:
1 For soil slopes, it may use grass, bush and plant such as geonets, geonet
mats or three-dimensional vegetation slope protection nets for greening.
2 For subgrade slopes such as sandy soil, gravelly soil, or rocky soil, which
are not suitable for plant growth, it may use geonets to plant grass, plant
belts, plant bags or ecological bags to plant grass for greening.
3 The ultimate tensile strength of the geonet mat shall not be less than 0.8
kN/m.
5.7.6 When geosynthetics are used for subgrade scour protection, it may use
mold bag concrete slope protection. When the cement mortar is filled in the
geo-mold bag, the allowable flow rate is 2 m/s ~ 3 m/s. When the concrete is
filled, the allowable flow rate is 2 m/s ~ 5 m/s. When underwater construction is
required, the allowable flow rate is not more than 1.5 m/s. For slope protection
and bottom protection with a severe erosion rate of 4 m/s ~ 5 m/s, it may use
woven geotextile. The rupture strength of the geo-film bag cloth shall not be
less than 40 kN/m and the elongation shall not be greater than 30%. The zonal
rupture strength of the woven geotextile shall be not less than 20 kN/m. The
material’s aging resistance shall meet the engineering needs.
5.7.7 When geosynthetics are used in the reinforced soil structure of subgrade
slopes, they shall meet the following requirements:
1 When the embankment’s fill slope is high and the slope is susceptible to
storm erosion, it may lay a two-way geogrid in the shallow layer of the
slope for enhanced protection. The ultimate tensile strength of the geogrid
shall not be less than 25 kN/m.
2 Reinforced earth embankments or reinforced earth retaining walls on steep
slopes should use plastic uniaxially stretched geogrids with high strength,
low elongation, small creep, good weather resistance and chemical
resistance. The ultimate tensile strength of a geogrid shall not be less than
35 kN/m; the nominal elongation shall not be greater than 10%.
5.7.8 When geosynthetics are used for subgrade treatment, they shall meet the
following requirements:
1 Reinforcement of cushions should use geogrids, geotextiles or geocells
with higher strength and smaller elongation. The vertical drainage in the
deep drainage consolidation method for soft soil foundations may use
drainage belts or bagged sand wells. For large-area processing sections,
it may use large-diameter seepage pipes or flexible pervious pipes as
water collection wells, to accelerate the consolidation and drainage of the
foundation.
2 The ultimate tensile strength of the geogrid, geotextile or geocell shall not
be less than 50 kN/m; the nominal elongation is not greater than 10%. The
tensile strength, corrosion resistance, flexibility of the core material of the
drainage belt as well as such performance indicators as vertical drainage
capacity, filter jacket strength, anti-filtration capacity shall comply with the
requirements of relevant standards. The bag materials for bagged sand
wells shall be made of tough polypropylene or other suitable geotextiles;
the ultimate tensile strength shall not be less than 15 kN/m; the mass shall
not be less than 95 g/m2; the equivalent aperture O95 shall be not more
than 0.05 mm; the permeability coefficient shall be more than 5 x 10-5 m/s.
6.6 Treatment measures of subgrade bed
6.6.1 The natural foundation soil within the range of the bottom of the subgrade
bed complies with the provisions of clause 6.3.2 of this code. If the natural
compactness does not meet the requirements of clause 6.5.3 of this code, it
may take measures such as cutting & backfill or rolling compaction.
6.6.2 If the soil or filler within the range of the bottom of the subgrade bed does
not meet the requirements, it may be treated by taking the replacement or
reinforcement measures.
6.6.3 When the subgrade bed is affected by groundwater, it should take
measures such as lowering the groundwater level and setting up embankment-
type cutting, to reduce and empty the water in the area of the subgrade bed.
6.6.4 For the semi-filled and semi-cut subgrade bed on steep slope section, the
range not less than 1 m below the subgrade bed at the semi-cut side shall be
cut and filled; the filler shall meet the requirements of clauses 6.3.1 and 6.3.2
of this code.
7 Embankment
7.1 General provisions
7.1.1 The height of the embankment slope shall be reasonably determined in
combination with railway grade, track type, foundation conditions, source of filler,
land use nature, environmental factors, which should not exceed 20 m.
7.1.2 The surface treatment of the subgrade of the embankment on stable slope
section shall meet the following requirements:
1 When the surface slope is slower than 1:5, it shall remove the vegetation
on the surface.
2 When the slope of the ground surface is (1:5) to (1:2.5), it shall cut steps
on the original surface; the width of the steps shall not be less than 2 m.
When the overburden on the bedrock surface is thin, it should first remove
the overburden before digging the steps; when the overburden is thick and
stable, it may dig the steps directly on the original ground surface.
7.1.3 The safety factor of sliding stability of the subgrade and the soft layer
below subgrade for the steep slope embankment which has a lateral steep
slope on the ground surface steeper than 1:2.5 shall not be less than 1.25.
When the requirements are met, it shall design the steps on the original ground;
2 The maximum particle size of the filler for ballasted track railway with a
design speed of 200 km/h shall not be greater than 150 mm.
3 The maximum particle size of the filler for ballast-less track railway and the
ballasted track railway with a design speed of 200 km/h or more shall be
not more than 75 mm.
7.2.5 When the embankment is filled with different fillers, it shall meet the
following requirements:
1 When the seepage soil is filled above the non-seepage soil, the top surface
of the non-seepage soil layer shall be provided with a 4% herringbone
drainage slope to both sides.
2 When the particles of the upper and lower layers of fillers do not meet the
requirements of the formula (6.1.4) of this code, it shall set isolation
cushion or take other measures on the parting plane. When the filler for
the lower layer is chemically improved soil, it is not subject to the
restrictions of this clause.
7.2.6 When the embankment below the subgrade bed uses sandy soil in group
C2 and group C3, it shall take reinforced protection measures.
7.3 Compaction criteria
7.3.1 The compaction control index of the embankment’s filler below the
subgrade bed shall meet the following requirements:
1 For fine-grained soil, sandy soil, gravelly soil, macadam soil, block stone
soil, etc., it shall use the compaction coefficient and foundation
deformation coefficient as control indicators.
2 The improved soil shall use the compaction coefficient and 7d saturated
unconfined compressive strength as control indicators.
7.3.2 The compaction criteria of the embankment filler below the subgrade bed
shall meet the requirements in Table 7.3.2.
or slope foot walls with a width of not less than 1 m.
8 Cutting
8.1 General provisions
8.1.1 The height of the cutting slope shall be comprehensively determined
according to the lithology of the stratum, the degree of fragmentation of the rock
mass, the hydrological conditions. It should not exceed 30 m.
8.1.2 Soil, soft rock and strongly weathered hard rock cuttings shall be provided
with side drain platforms, the width of which shall not be less than 0.5 m; cutting
slopes shall be provided with slope platforms at the interface between soil and
rock boundaries, permeable and impermeable layers; the width should not be
less than 2 m.
8.1.3 In the sections where groundwater develops, drainage is difficult, swelling
soil (rock) presents, it may be designed in the form of embankment-type cutting
structure.
8.1.4 The design of cuttings shall reduce the damage to natural vegetation and
mountains and prevent inducing geological disasters.
8.1.5 High soil slopes and weak loose rock cuttings should, according to the
engineering geological conditions, rock stratum weathering and joint
development, combined with construction technology, use the layered
excavation, layered stabilization, slope foot pre-reinforcing technology.
8.2 Soil cuttings
8.2.1 The form and slope rate of soil cutting slopes shall be comprehensively
determined in accordance with engineering geology, hydrogeology and
meteorological conditions, slope height, water drainage measures, construction
methods, etc., combined with the investigation and mechanical analysis of
natural stable hillsides and artificial slopes.
8.2.2 When the height of the soil cutting slope is less than 20 m, the slope rate
can be determined according to Table 8.2.2; when there are special conditions
such as unfavorable stratum interfaces, sliding surfaces, groundwater cropping,
etc., it needs to be determined through stable analysis and calculation.
mixed with not less than 3% cement in layers; the compaction criteria shall
meet the compaction coefficient K ≥ 0.95, foundation deformation
coefficient K30 ≥ 150 MPa/m, dynamic deformation modulus Evd ≥ 50 MPa.
2 Passenger-freight shared railway with a design speed of 200 km/h may be
filled with graded macadams in a layered manner. The range 2.0 m away
from the structure shall be mixed with not less than 3% cement; the
compaction criteria shall meet the compaction coefficient K ≥ 0.95,
foundation deformation coefficient K30 ≥ 150 MPa/m.
3 Heavy-duty railways shall be filled with group A fillers in layers. The
compaction criteria shall meet the compaction coefficient K ≥ 0.95,
foundation deformation coefficient K30 ≥ 150 MPa/m, dynamic deformation
modulus Evd ≥ 40 MPa.
4 Ballasted track intercity railways with design speeds below 200 km/h and
passenger-freight shared railway shall be filled with group A fillers. The
compaction criteria shall comply with the relevant provisions of the bottom
layer of the subgrade bed in clause 6.5.3 of this code.
5 The grading range of graded macadam shall comply with the provisions of
clause 5.2.11 of this code.
9.2.5 The fillers in the immersed part of the transition section shall meet the
technical requirements for pervious soil fillers except for graded macadams.
9.2.6 The abutment pit of the transition section of the high-speed railway,
ballast-less track and ballasted track intercity railway with a design speed of
200 km/h shall be backfilled with concrete or layered with gravel or improved
soil. The foundation pit of the bridge abutment in the transitional section shall
be filled in layers with gravel and improved soil. Concrete shall meet the design
strength requirements. The gravel and improved soil...
......
(Above excerpt was released on 2020-03-31, modified on 2021-06-07, translated/reviewed by: Wayne Zheng et al.)
Source: https://www.chinesestandard.net/PDF.aspx/TB10001-2016