SLOPE Mass Rating Slope Stability aj&k university engeneering geology

1. Group 3rd
Engineering geology
MORNING 5Th SEMESTER
PRESENTED TO;
Sir Sohail
UNIVERSITY OF AZAD
JAMMU & KASHMIR
MUZAFFARABAD
1

2. Name : Haroon Ahmed Niazi
Roll no : 20
2

3. 3

4. 4
:Introduction to
S.M.R:
• SMR is a Slope stability system of
classification.
• It is developed by (Romana, 1985) as a
modification of Bieniawiski’s rock mass
rating.
• It is an important approach to assess the
engineering behaviour of a rock slope.

5. • It describes strength of an individual rock outcrop or
slope.
• Now a days, SMR is included in most of the
educational programs of technical studies in Civil
and Geological Engineering.

6. 6
Slope mass rating(SMR) :
SMR = RMR(b) - (F1 .F2 .F3) + F4
• The SMR is calculated by subtracting factorial
adjustment factors of the
joint-slope relationship (F1.F2.F3).
• And also add a factor depending on method of
excavation (F4) , in BASIC RMR.

7. 7
Basic RMR :
• The RMR(b) is evaluated according to
(Bieniawski’s 1979) proposal.
RMR(b) = R(UCS)+R(SD)+R(CD)+R(GD)+R(RQD)
1. Uniaxial compressive strength (UCS).
2. Spacing of discontinuities (SD).
3. Condition of discontinuities (CD).
4. Ground water inflow through
discontinuities(GD).
5. Rock quality designation (RQD).

8. 8
• RMR developed originally for
underground excavations (tunneling or
mining)and have been modified for
slope stability application.
• Hence, RMR is very useful as a tool
for the assessment of slope stability.

9. 9
F1 : Depends on parallelism between joints and slope face
strike .
• Its value ranges from 0.15 to 1.0 .
• 0.15 in case when the angle between the joint plane and the
slope face is more than 30 degrees and the failure probability
is very low.
• 1.0 in case when both are near parallel.
F1 = (1- SinA)^2
where, A is the angle between joints and slope face strike .
Adjustment factors (F1,F2,F3 and F4)

10. 10
F2 : Is related to joint dip angle in the planar
failure mode.
• Its value ranges from 0.15 to 1.0 .
• 0.15 in case when the dip of the joint is less than 20
degrees.
• 1.0 when joints with dip more than 45 degrees.
• For toppling mode of failure, F2 remains equal to 1.0 .
F2 = Tan^2 (B)
where, B denotes joint dip angle .

11. 11
F3 : Refers to the relationship
between the slope face strike and joint
dip angle .
Its value ranges from 0 to -60
• F1,F2 and F3 are adjustment factors
related to joint orientation with
respect to slope orientation.

12. Planar failure mode
• Romana (1985) used planar and toppling failures for his
analysis.
Toppling failure mode

13. Planar failure
In planar failure, slope face and joints(discontinuity)
strike parallel to each other.
Slope
face(F1) (F2)
(F3)

14. Toppling failure
• It consist of forward tilted rock mass with joints dip angle is more then 45 degrees.
• F2 is remains 0.1 .

15. Wedge failure
• In wedge failure two or more intersecting discontinuities (joints).
• It have been considered as a special case of plane failures.

16. 16
Its value ranges from -8 to +15 .
F4 : Is a factor for the method of excavation and
its adjustment factor has been fixed empirically as
shown in; Table 2.1

17. Natural slopes, are more stable ,because of long
time erosion and built in protection mechanism,
F4 = +15 .
Blasting or mechanical excavation, applied with
sound methods does not change slope stability
conditions, F4 = 0
Deficient or poor blasting, damages the slope
stability, F4 = -8 .

18. Presentation
Ahtaisham Shaukat
Roll No. 21
 TOPIC :
CORRECTION PARAMETER FOR SMR

19. Slope mass rating
SMR = RMRb - (F1 × F2 × F3) + F4

20. Parameters

22.  Romana (1993) proposed the following
continuous Function for computation of F1 and
F2:
 F1 = (1-sinA)2.
 F2 =( tan)2 B.
 Where A is the parallelism between discontinuity
and slope strikes .
 B is the discontinuity dip (βj).

24.  Table 3 shows the different stability classes and
the empirically found limit values of SMR
associated to the different failure modes.
 Field experience indicates that slopes with a SMR
values lower than 20 fail very quick.
 And that no slopes with SMR value below 10 are
possible.

26.  Romana (1985) also proposed some guidelines for the use
of remedial measures based on SMR.
 it provides a first approximation during the first
preliminary stages of a project.
 Normally no support measures are needed for slopes with
SMR values of 75-100.
 Even, some stable slopes have been found with SMR
values of 65.
 Additionally, no totally re-excavated slope has been found
with SMR over 30.

28. Continuous functions
 Tomas et al. (2007) proposed asymptotical continuous
functions for F1, F2 and F3 correction factors.
 It show maximum absolute differences against original
discrete functions smaller than 7 points.

29.  These functions are very useful to be implemented into.
 Computer routines for SMR calculus (e.g. Riquelme et al.,
2014a).
 And on Geographical Information Systems, GIS (e.g. Filipello
et al. 2015).

31. A: parallelism between the discontinuity and the
slope strikes;
B: discontinuity dip, βj;
C: discontinuity and slope dip relationship

34. Adaptations
 Chinese slope mass rating(CSMR).
 Modified slope mass rating(M-SMR).
 Rock hazards rating system(RHRS).
 SMR-TOOL.
 Fuzzy slope mass rating(FSMR).

35. Chinese slope mass rating
(CSMR)
 It was developed by Chen(1995) to adopt SMR system to
rock slope conditions in china.
 It is used as a national standard for slope in design and
construction of Dams and Hydroelectric power Stations.
 It Adapts two additional factors in SMR:
1) Height of slope(if more then 80meter).
2) Conditions of discontinuity.

36.  CSMR = E×RMR + L×(F1×F2×F3)
Where ‘E’ is slope height and ‘L’ is discontinuity
conditions
E = 0.43+0.57×(80/H) ,. H = slope height
Value of L ranges from 0.7-1
1 = Faults , long seams filled with Clay
0.8-0.9 = bedding plan, large scale joints with gouge
0.7 = Joints, tightly interlocked bedding planes

37. Fuzzy slope mass rating (FSMR)
 It is based on Fuzzy set theory.
 Daftaribesheli et al.(2011) developed FSMR by
applying Fuzzy set theory to SMR system.
 It evaluate rock slope stability of open pit mines.

38. Modified slope mass rating ( M-SMR)
 It was proposed by Rahim et al.(2009; 2012).
 It is a modification of SMR in terms of Parameters
calculation and determination method.
 It us used for rating rock mass of heterogeneous
formations composed of alternations of different
lithologies.

39. Rock hazards rating system(RHRS)
 It was developed by Pierson et al.(1990) for the
assessment of Rock fall risk along roads.
 Budetta (2004) Incorporated SMR for hazards
evaluation in a broad scope .

40. SMRTool
 It is a calculator programmed in MS EXEL used for computing SMR.
 It was developed by Riquelme et al. (2014) in an open access format.
 Values of five parameters of RMR and 4 adjustment factors are compute.
 Besides SMR value it also give
(1) stability of slope (3) system of support recommend
(2) Mode of failure. By Romana(1993)

42. Validations of SmR

43.  SMR has been used worldwide during last thirty
years in following ways
(1)As a geomechanics classification for rating rocky slopes.
(2)Considering F1,F2,F3 as parameters to quantify the effect of
discontinuities on stability of slope.
(3)As a compliment to other methods.
(4)As a preliminary and complementary method of engineering
works.

44. Limitations of SMR
 SMR is slightly conservative.
 The extreme values of F3 (-60 and -30) proposed by
Bieniawski are something difficult to cope with.
 SMR does not take into account the effect of height.

45. NAME IFTIKHAR SHAFIQUE
ROLL NO. 26

46. TOPIC OF THE PRESENTATION
 Classes of Slope Mass Rating
 Recommended Support Measures for Each Stability Class

47. Classes OF SMR
 The SMR is divided in to Five general classes
 The Classes are classified on the bases on Rating (value).
 Each Class Shows The Stability and the protection measures for the Area.
 The various Type of supports are used stable the slope.

48. Classes of SRM

49. Recommended Support Measures

50. CLASS IA
CLASS SMR SUPPORT
IA 91-100 None

51. CLASS IB
CLASS SMR SUPPORT
IB 91-100 None,Scaling

52. What is scaling?
 Rock scaling is generally defined as the removal of loose rock from
slopes –
 This process is done by removing loose surface material presenting a
rock fall hazard, usually with pry-bars and picks –

53. CLASS II A
CLASS SMR SUPPORT
II A 71-80 Toe ditch or fence.
Nets spots

54. What is Toe Ditch?
 A water route processed in cut areas, used for
applying surface drainage.
 It is a proper channel of water flow out.

55. NET
 Nets over the slope are used to avoid free fall of rock
pieces.

56. CLASS II b
CLASS SMR SUPPORT
II b 61-70 Toe ditch or fence.
Nets Spot or
systematic bolting

57. FENCE
 Fence is used for the protection of the slope.

58. CLASS III a
CLASS SMR SUPPORT
III a 51-60 Toe ditch and/or nets Spot or
systematic bolting Spot shot
Crete

59. BOLTING
 Bolting in slopes is a worldwide used technique.
 Bolts in slopes are used as a combined immediate and
permanent support.

60. SHOT CRETE
 Shot crete is concrete (or sometimes mortar) conveyed
through a hose and pneumatically projected at high velocity
onto a surface.

61. CLASS III b
CLASS SMR SUPPORT
III b 41-50 (Toe ditch and/or nets)
Systematic bolting.
Anchors Systematic shot
Crete Toe wall and/or
dental concrete

62. DENTAL CONCRETE
 Dental concrete is used to fill in cavities and large joints to prevent
ingress of water .
 dental concrete can protect the rock
surface against further weathering.

63. CLASS IV a
CLASS SMR SUPPORT
IV a 31-40 (Toe ditch and/or nets)
Systematic bolting.
Anchors Systematic shot
Crete Toe wall OR concrete

64. CLASS IV B
CLASS SMR SUPPORT
IV b 21-30 Systematic shot Crete Toe
wall OR RCC concrete

65. DENTAL CONCRETE
 Reinforced concrete, or RCC, is concrete that contains embedded steel
bars.
 THE steel bars are used with concrete with respect to design.

66. CLASS V a
CLASS SMR SUPPORT
V a 11-20 protection wall or
anchored wall

67. HAMZA IRSHAD
ROLL NO. 25

68. Slope and slope stability
Slope are an exposed ground surface that
stands at an angle with the horizontal
The term slope stability may be defined as
resistance of inclined surface to failure by
sliding or collapsing.

69. SSR (slope stability Rating)
 It has been purposed in Iran to study the
stability of fractured rock slopes.
 In this system , the stability can be evaluated
by means of slope design charts.
 Estimates of rock slope stability are required
by the civil and mining engineering industry
for a wide variety of projects.

70.  Many rock mass classification system have been developed over 100 years since first attempt
were made to formalize an empirical approach to tunnel design.
 Some of the classification systems like RMR (Bieniawski 1973) and (Barton & lunde 1974) have
gained broad acceptance in the civil and mining industry while others such as those suggested
by Tarzaghi (1946) and Palmstorm (1996) are specific to underground openings.
 All of these rock mass classification system have been applied successfully in tunneling and
underground mining. But most of them have limitations and shortcomings , when it comes to
rock slope problems.

71. Slope stability: In naturally occuring slopes like among hill slopes and
river sides, the forces of gravity tends to move soil from high levels to low levels and the
forces that resist this action are on account of the shear strength of soil.
 Presence of water increases weight and reduces shear strength and hence decreases
stability.
 Weights of man made structures constructed on or near slopes tend to increase the
destablizing forces and slope instability.

72. Slope stability Rating (SSR)
classification system
 SSR has five parameters whose relative effect on the stability of
fractured rock slopes.
 These fractured rock slopes examined precisely based on data
retrieved from different rock slope sites.
 Overall rating of the rock mass is obtained by summation of all
individual ratings of each parameter.
 Data collected from different sites to get the information of dry unit
weight , Intact rock properties and final design geometry.

73. Parameters of SSR
1. Uniaxial compressive strength (UCS) of
intact rock.
2. Rock type (Lithology).
3. Slope excavation method.
4. Saturation of slope.
5. Horizontal earthquake acceleration.

74. Parameters
1 UCS (In Mpa) 0-10
0
10-25
7
25-50
18
50-100
28
100-150
37
2 Rock type Group 1
0
Group 2
4
Group 3
9
Group 4
17
Group 5
20
Group 6
25
3 Slope excavation
method
Waste
damp
-11
Poor
blasting
-4
Normal
blasting
0
Smooth
blasting
6
Presplittin
g
10
Natural
slope
24
4 Ground water
rating
Dry
0
0-20%
-1
20-40%
-3
40-60%
-6
60-80%
-14
80-100%
-18
5 Earthquake force
rating
0
0
0-15g
-11
0.20g
-15
0.25g
-19
0.30g
-22
0.35g
-26

75. Main objective of slope stability
Analysis
 Main objective of slope stability analysis are finding endangered
area.
 Investigation of potential failure mechanism.
 Determination of the slope.
 Sensitivity to different triggering mechanisms.
 Designing of optimal slopes with regard to safety.

76. Within the last decade (2003) slope
stability Radar has been developed to
remotely scan a rock slope to monitor the
spatial deformation of the face.
Small movements of a rough wall can be
detected with sub millimeter accuracy by
using inter_ferometry techniques.

77. Slope stability Radar

78. Factors affecting slope and stability
1. Gravity
2. Erosion
3. Water seepage force
4. Sudden drawdown
5. Earthquakes

79. Types of slopes
Natural
 Hilly and valley slopes.
 River terraces and
coastal cliffs.
Man made
 Embankment for highways and earth
dams.
 Excavation dumps and waste heaps for
landfill.
 Landscape development.

81. Rock Slope Rating (RSR)
• A rock slope rating (RSR) system has been developed for
evaluation of rock slope stability under a variety of
geological conditions and engineering requirements .
• RSR system evaluates the probability of failures for plane
and wedge sliding and toppling and circular failures.
• Probability of each failure is determined individually.

82. P{f}, % Slope Mass Quality
<20 Highly Stable
20-40 Stable
40-60 Fair
60-80 Unstable
80-100 Highly Unstable
Table: Probability of failure to slope mass quality

83. • The main categories for input parameters are
summarized as follows.
Geological features
• Various types of slope mass to which the RSR can be
applied: massive rock, blocky rock, bedded rock,
heavily jointed rock , soft rock and hard-soft inter
bedded rock.

84. Safety requirements
• The system classifies the engineering applications
of rock slope into four levels of safety, based on the
type of engineering structures (e.g, railroad,
housing, major highway, spilway, dam abutment,
mined road, etc)

85. Ground water conditions
• The ground water condition is classified in terms of
its level as compared to the slope height.
• The options are from completely dry to water level
up to 25% 50%, 75% or 100% of the slope height. If
the condition is unknown, the system makes further
inquiry about the climate where the slope is situated.
• Two options are available: tropical and arid.

86. Slope geometry
• Slope geometry includes orientation, height,
angle and curvature.
• Three slope shapes can be selected: convex,
concave and straight faces.

87. Slope
Height
Slope Face
Angle
Ground
Water
Degree of
Weathering
(m) Rate Degree Rate (%) Rate Condition Rate
5-7 1 20-25 0 0 0 Fresh 2
7-10 5 25-30 1 25 5 Slightly 4
10-15 8 30-35 2 50 10 Moderately 6
15-20 10 35-40 3 75 10 Highly 8
>20 10 40-45 5 100 10 Completely 10
45-50 6 Unknown *5 or 10 Unknown 5
50-55 8
55-60 9
Table: Rating factors for evaluation of circular failure.

88. Joint characteristics
• The system requires detailed joint
characteristics, including orientation, average
spacing, continuity, aperture, filling and
roughness of all joint sets.

89. Geo-mechanics parameters
• Rock density, uni -axial compressive strength and
shear strength of all joint sets are considered in the
stability evaluation.

90. • The probability of failure p{f} in
percent for each mode can then be
calculated by:
• P{f}= Σ{Rn ∗ In}
where Rn is the rating for each parameter, In is the
influencing factor for the corresponding parameter, and n
represents type or number of the parameters considered for
each slope

91. Regard : Group 3
Roll no : 20 - 27