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Word file of the Chapter 8 Protocol Sheets in“Rock Engineering Design” by Feng and Hudson

The Protocol Sheets have been provided in this Word file to allow users to be able

to complete the Sheets directly. The Sheets and an illustrative completed example

are explained in Chapters 8 & 9 of the book.

8 PROTOCOL SHEETS

The purpose of this Chapter is to explain and present the Protocol Sheets to be used for

recording the information relevant to the complete process of modelling and design and hence

support the technical auditing for a rock engineering project, the word ‘Protocol’ being used

here to indicate a pre-defined written procedural method. The Protocol Sheets follow the

philosophy outlined in the first five chapters of the book. Seven such sets of Protocol Sheets are

suitable to provide the necessary information recording the data and decisions leading to the

rock engineering design, including the during- and post-construction feedback for back analysis.

These seven sets of Protocol Sheets cover the following subjects.

- Objectives and overall approach to the project

- Geological setting and site investigation

- Modelling

- Design

- Technical auditing

- Feedback and back analysis

- Summary and conclusions

Currently, there is no international procedure for checking whether rock engineering

modelling and design are adequate for the purpose. In other areas of engineering constructions,

e.g., the manufacture of aeroplanes, there can be highly detailed checks on all aspects of the

construction process. It is not the intention here to reproduce such detailed quality assurance

1

procedures but to provide an overview auditing method to ensure that the modelling and design

operations are suitable for the purpose. The term ‘technical auditing’ means the examination of

the technical content of a rock mechanics model or rock engineering design to establish if it is

adequate for the purpose—given the difficulties with some of the rock mechanics factors and

the idiosyncrasies of the different engineering projects. Key overview technical auditing

questions are:

- What is the work/project objective?

- Have the relevant variables and mechanisms been identified?

- Is the model/code adequate?

- Are the data adequate?

- Has the model been implemented properly?

- What are the prediction/back analysis protocols?

The technical auditing procedure ensures transparency of the methods used, traceability of

analysis methods and associated decisions, and confirms that investigation of the key factors has

been implemented. In particular, hazard scenarios can be investigated. Note that technical

auditing can be used concurrently with the work or subsequently when the work is completed.

Naturally, it is preferable if the Protocol Sheets are completed and the technical auditing applied

on a continuous basis during the operation of the modelling and design work. In rock mechanics

and rock engineering, there are still many unresolved issues, such as the most appropriate failure

criterion, the best way to characterise fractures, etc., so the technical auditing is conducted

within the current scientific framework with a consensus approach being the best way to deal

with such unresolved issues.

The sets of Protocol Sheets 1–5 can be used before construction. The set, Protocol Sheet 6, is

used as the construction starts with feedback information being received and back analysis

being possible. Finally, the result of completing and auditing the work as described in the

Protocol Sheets is summarised in Protocol Sheet 7.

2

8.1 PROTOCOL SHEET 1: Objective and Overall Approach to the Project

It is necessary at the outset to establish the objective and overall approach to the project. This is

because there can be quite different philosophies and requirements for the different types of

project. For example, in civil engineering projects there is a requirement to avoid significant

rock failure. Conversely, in the block caving method of metal mining, the whole procedure

depends on successfully achieving progressive failure of a large rock mass.

PROTOCOL SHEET 1

Objectives and Overall Approach to the Project

(see Table 3.1, Item 1)Have the project, modelling and design objectives

been discussed?

List the main personnel (with their affiliation) who

have discussed the project

What were the dates of the discussions?

Have the objectives been clearly stated?

State the project objective

State the modelling objective

State the design objective

Are there any supplementary objectives?

Have any difficulties been encountered in

specifying the objectives?

Give the name of the person completing this sheet

Give the name of the person checking the contents

of the completed sheet

Date of completion of this sheet

Location of electronic storage of this Protocol Sheet

Location of back-up electronic storage of this

Protocol Sheet

8.2 PROTOCOL SHEETS 2: Geological Setting and Site Investigation

3

The purpose of this overview Protocol Sheet is to record the information concerning the details

of the geological setting and site investigation. There are then seven sub-sheets numbered as

follows.

2.1 Geological setting

2.2 In situ rock stress

2.3 Intact rock

2.4 Fractures and faults

2.5 Rock mass properties

2.6 Hydrogeological properties

2.7 Other special characteristics/parameters required, e.g. temperature

In each of these sub-sheets, overview data are requested, together with reference to the full

information contained in reports, electronic databases, photographs, etc. If necessary, the user

should provide an associated data sheet/document containing the detailed information.

PROTOCOL SHEET 2

Geological Setting and Site Investigation

(Overview sheet with example data contained in sub-sheets 2.1 to 2.7)Has a structural geologist visited the site and

provided a report on the geological setting?

Has the in situ rock stress been measured?

Is there information on the intact rock properties?

Have the fractures been characterised, including

large features such as brittle deformation zones?

Have the rock mass properties been estimated?

Have the hydrogeological properties been

estimated?

Are there any other key rock mass parameters

involved in the project?


establishing the information above?



4





Protocol Sheet

5

8.2.1 PROTOCOL SHEET 2.1 :Information on the Geological Setting

In modelling and designing a project to be located on or in a rock mass, it is essential to have an

understanding of the geological setting. This provides crucial information on the configuration

of the rock masses and their likely content—which is required for model construction and

hazard analysis.

PROTOCOL SHEET 2.1

Information on the Geological Setting

How has the information on the geological setting

been established?

What are the ages of the rocks?

What rock units are present?

To what extent has the rock been tectonically

deformed?

Are there any faults (or more generally brittle

deformation zones) evident from the geological

setting?

Has the area been subject to glaciations in the past?

Is the rock susceptible to weathering?

Is there currently a Quaternary soil cover?

Are there any special features associated with the

geological setting?


establishing the geological setting?

Where is the full information on the geological

setting currently held?

6







Protocol Sheet

7

8.2.2 PROTOCOL SHEET 2.2: In Situ Stress

Knowledge of the in situ stress is required both for basic considerations of the possibility of

rock failure and as a required boundary condition input for numerical models.

PROTOCOL SHEET 2.2

In Situ Stress

Have the regional stress circumstances at the site

been established from stress maps or other sources?

Has the rock stress been measured at the site?

What type of method has been used for in situ

measurement?

How many locations were measured for in situ

stress?

Is the major principal stress orientated vertically,

horizontally, or at some other orientation?

In what azimuth direction is the major horizontal

stress?

What are the magnitudes and orientations of the

three principal stresses? Include a stereogram.

What are the principal stress ratios: 1/2 , 1/3 ,

2/3 ?

Does the rock overburden vary above the

anticipated project location?

Is there any reason to expect that the stress values

may vary across the site because of, e.g. varying

surface topography, effect of major faults, etc.?

Have the four ISRM Suggested Methods on rock

stress estimation been studied and used?

8

Give the location of the report on the complete rock

stress estimation for the project site


estimating the in situ stress?




Date of completing this sheet



Protocol Sheet

8.2.3 PROTOCOL SHEET 2.3: Intact Rock

The nature of the intact rock is crucial for many aspects of project modelling and design.

PROTOCOL SHEET 2.3

Intact Rock

Have the intact rock properties been considered

within the geological setting, Protocol Sheet 2.1?

How many distinct types of intact rock are present at

the site?

Has the rock been metamorphosed/altered in any

way by geological processes?

Have the intact rock properties been measured?

Which tests established the intact rock properties?

Which standards or suggested methods have been

employed in the determination of intact rock

properties?

9

What are the mean Young’s moduli and Poisson’s

ratios of the intact rocks at the site?

What are the mean compressive strengths of the

intact rocks present at the site?

What are the mean tensile strengths of the intact

rocks present at the site?

Have complete stress–strain curves been obtained,

i.e., the post-peak characteristic in addition to the

pre-peak characteristic?

Any other intact rock data available, e.g., spalling

strength, fracture toughness, etc.?

Is the intact rock susceptible to weathering?

Are there any issues connected with intact rock

anisotropy, inhomogeneity or time dependence?

Have any difficulties been encountered in estimating

the intact rock properties?

Where is the borehole rock core located?

Where are the intact rock data located?







Protocol Sheet

10

8.2.4 PROTOCOL SHEET 2.4: Fractures and Faults

Knowledge of the presence of fractures and faults is essential to avoid major problems and as

input to computer programs.

PROTOCOL SHEET 2.4

Fractures and Faults

What information can the knowledge of the geological

setting provide about the rock fracturing and faulting?

Are any major faults (or brittle deformation zones)

present?

Have such faults been characterised in terms of their

location, geometry (dip/dip direction) and other features

such as zone thickness?

Have the faults been intersected by boreholes, or have

they been visible at outcrops or in underground

excavations?

Have the fractures been measured?

Which method has been utilised to determine rock mass

(discontinuity) characteristics (e.g., scanline survey,

window mapping, and measurements along the sidewalls

of an underground opening or geotechnical logging along

borehole cores)?

If borehole cores have been used, has a comparison been

carried out between the measurements obtained from

cores and surface techniques?

How many fracture sets are present?

What are the orientations of the fractures (supply one or

more stereograms)

11

What other information concerning the fractures is

available, e.g., tracelength, roughness, aperture, etc.?

Do the fracture characteristics vary across the site, so that

structural fracture domains may be necessary?

Have any difficulties been encountered in estimating the

fracture properties?

Where is the fault and fracture information held?


Give the name of the person checking the contents of the

completed sheet



Location of back-up electronic storage of this Protocol

Sheet

8.2.5 PROTOCOL SHEET 2.5: Rock Mass Properties

The rock mass properties are a function of the combined effects of the intact rock and the

fractures, and possible external effects such as the applied stress.

PROTOCOL SHEET 2.5

Rock Mass Properties

What information can the knowledge of the

geological setting provide about the rock mass

properties?

Have the main mechanical properties of the rock

masses present been established?

Have the rock mass properties been measured

12

directly?

Have empirical methods been used to estimate the

rock mass properties, e.g., via RMR, Q, GSI, BQ

ratings?

Have numerical methods been used to estimate the

rock mass properties, e.g., through the use of the

3DEC program with the intact rock and fracture

properties input to the model?

What are the rock mass deformation and strength

properties?


estimating the rock mass properties?

Where is the rock mass information held?







Protocol Sheet

8.2.6 PROTOCOL SHEET 2.6: Hydrogeological Properties

For many projects, knowledge of the rock mass permeability/hydraulic conductivity and other

characteristics of water flow through the rock mass is crucial for the success of the project and

for avoiding/mitigating water hazards.

13

PROTOCOL SHEET 2.6

Hydrogeological Properties

What information can the knowledge of the

geological setting provide about the rock mass

hydrogeological properties?

Is water flow through the rock mass occurring

mainly through the intact rock or through the rock

fractures?

Have the rock mass hydraulic conductivity and/or

rock fracture transmissivities been estimated by any

means?

Have the rock mass hydraulic conductivity and/or

rock fracture transmissivities been measured

directly?

What are the likely water head pressures to be

encountered in the project?

What are the likely fracture transmissivity values?

Are high water pressures likely to be present when

faults are intersected by the rock excavation?


specifying the rock mass hydrogeological

characteristics?

Where is the hydrogeological information held?






14


Protocol Sheet

8.2.7 PROTOCOL SHEET 2.7: Other Special Parameters

Depending on the purpose and nature of the rock engineering project, information on a variety

of extra rock mass characteristics may be required, e.g., likely TBM excavation rates,

temperature of the rock, degree of foliation, etc.

PROTOCOL SHEET 2.7

Other Special Characteristics/Parameters Required

Is information on any ‘non-standard’ rock

characteristic required for modelling and designing

the project?

Which extra characteristics are required?

Have these been estimated?

Have these been measured?

Which methods (standard or suggested) have been

employed for the determination of extra

characteristics?


establishing the values of these

characteristics/parameters?

Give the values of the these

characteristics/parameters

Where is the information on these extra parameters

held?



15





Protocol Sheet

16

8.3 PROTOCOL SHEETS 3: Modelling

This Protocol Sheet and the associated sub-sheets follow the same pattern as for Protocol Sheet

2 but the subject is now modelling. In Chapter 2 we showed the Figure 2.1 diagram of the eight

main modelling methods; this diagram is reproduced below as Figure 8.1.

Protocol Sheet 1 covers the overall objectives and approach to the rock engineering project,

including the modelling objective. Protocol Sheets 2 cover the geological setting and the site

investigation aspects. Now Protocol Sheets 3 cover the eight main modelling aspects. The roles

of these three Protocol Sheets are indicated in Figure 8.1.

Figure 8 1. The eight main types of modelling to support rock engineering design (following Figure 2.1).

Accordingly, there are ten Protocol Sheet 3 sub-sheets as listed below. These follow the eight

main modelling methods in the order of Method A through to Method D in Figure 8.1 with, in

each case, the Level 1 procedure taken firstly and the Level 2 procedure taken secondly. The

Protocol Sheet 2

Protocol Sheet 1 Protocol Sheet 3Objective

Method A Method B Method C Method D

Lab

and

field

test

s

Use ofpre-existing

standard methods

Design based on forward analysis Design based on back analysis

Level 2Not 1:1 mapping

Level 11:1 mapping

Precedent type

analyses and

modifications

Analytical methods,

stress-based

Rock massclassification,

RMR, Q,GSI, BQ

Basic numerical methods,

FEM, BEM, DEM, hybrid

Databaseexpert

systems, & other

systemsapproaches

Extended numerical methods,

fully-coupled models

Integratedsystems

approaches, internet-based

Site

inve

stig

atio

n

Construction and monitoring

17

ninth Protocol Sheet 3 sub-sheet covers the eventuality that another type of modelling is

additionally being conducted, e.g., physical modelling. The tenth Protocol Sheet 3 sub-sheet

covers the use of the different methods in combination or sequence—because more than one

method is usually used.

3.1 Pre-existing standard methods

3.2 Precedent type analyses

3.3 Analytical methods

3.4 Rock mass classification

3.5 Basic numerical models

3.6 Database and systems approaches

3.7 Extended numerical models

3.8 Advanced systems approaches

3.9 Alternative type(s) of modelling

3.10 Use of the different methods in combination or sequence

18

PROTOCOL SHEET 3

Modelling

(Overview sheet with associated sub-sheets 3.1 to 3.10 following)

What is the purpose of the completed or anticipated

modelling?

Is the type of modelling being used covered by one

or more of the eight methods shown in Figure 8.1?

If so, state which of the eight main modelling

methods is/are being used?

If the modelling method being used is not one of the

eight methods shown in Figure 2.1 or 8.1 (Feng and

Hudson, 2011), specify the type(s) of modelling

being used.

Is the modelling being conducted as one exercise or

is the modelling sequential in some way?

Have all the input parameters for the modelling

method(s) been satisfactorily obtained?

Has it been possible to verify the modelling in any

way, i.e., has there been any check of the results

obtained by two or more modelling methods?

Has it been possible to validate the model in any

way, i.e., check that the modelling results

correspond with the rock reality?

Has the modelling method raised any unforeseen

difficulties?


19






Protocol Sheet

20

8.3.1 PROTOCOL SHEET 3.1: Pre-existing Standard Methods

The simplest design approach is to use a pre-existing standard method, e.g. a standard type of

tunnel lining, without any further consideration. Although most projects now require more

design than the direct application of a pre-existing method, it is possible that some

circumstances will allow this, particularly if there is specific experience of the method at an

adjacent location in the same rock mass.

PROTOCOL SHEET 3.1

Pre-existing Standard Methods

Why is it possible to use a pre-existing standard

method?

What is the pre-existing standard method that is to

be used?

Have any supporting modelling methods been used

to confirm the applicability of the standard method?

Is the rock mass consistent over the area/volume of

the rock mass involved?

Is it anticipated that in places the ground conditions

may locally not be suitable for the pre-existing

standard method?

Have any difficulties been encountered in ensuring

that the pre-existing method is suitable?

Where is the full information on the pre-existing

method being applied for the project currently held?





21



Protocol Sheet

22

8.3.2 PROTOCOL SHEET 3.2: Precedent Type Analysis (PTA)

A sophisticated extension of the pre-existing standard method is to use the Precedent Type

Analysis method pioneered in China which allows tailoring precedent construction to the

ground conditions for assessing rock stability in tunnels. It is a ‘semi-analytic’ method that

applies the geological conditions and relevant construction conditions of a so-called ‘typical’

project to a new tunnelling project for stability analysis (Li et al., 1998). Briefly, the method

uses rock mass classification and numerical analysis to compare the new site with the data for

past ‘typical’ projects. It is an analogue reasoning method.

Note: In Figure 8.1, Methods A to D represent an increase in complexity, so the PTA method

should really be further to the right—because it incorporates both rock mass classification and

numerical analyses; however, it is convenient to retain PTA’s position in Figure 8.1 because its

basis is the use of site data from previous typical projects.

PROTOCOL SHEET 3.2

Precedent Type Analysis (PTA)

Why is the PTA approach being used?

Has the exact Li Shihui et al. (1998, IJRMMS, 35,

6, 787-795) PTA been used?

(Li, S.H., Wu, X.Y. & Ma, F.S.: Application of Precedent Type

Analysis (PTA) in the Construction of the Ertan Hydro-Electric

Station, China. Int. J. Rock Mech. Min. Sci. 35 (1998), pp.787–

795.)

If not, what modifications have been introduced?

What type of rock mass classification was used in

the approach?

Which data from previous typical projects were

used?

What type of numerical analysis was used?

Was the flowchart in Figure 3 of Li Shihui et al.

(1998), used to guide the modelling work?

23

Did the use of PTA essentially follow the same

procedure as that used for the construction of the

Ertan hydroelectric station ( see Li Shihui et al.,

1998, IJRMMS, 35, 6, 787-795)?

Were any difficulties encountered in the application

of PTA?

Give the location of the report on the use of PTA




Date of completing this sheet



Protocol Sheet

8.3.3 PROTOCOL SHEET 3.3: Analytical Methods

The term ‘analytical methods’ here refers mainly to elastic solutions which provide the

distributions of stresses and strains for relatively simple geometries, with the assumptions of

continuity, homogeneity, isotropy and linear elasticity. An example is the Kirsch solution which

provides the stresses around a circular hole given the applied boundary stresses. Although these

solutions are for a highly idealised material, they can provide helpful guidance.

PROTOCOL SHEET 3.3

Analytical Methods

Why was an analytical method approach used?

Was the use of the analytical method supported by

24

any other methods?

Which particular analytical solution was used?

Are the strict CHILE conditions (continuity,

homogeneity, isotropy, linear elasticity) for an

elastic solution applicable for the rock mass being

considered?

Was the solution in 2-D or 3-D?

If rock mass parameters were used (e.g., not

required for stresses in the Kirsch solution but are

required for displacement), where did the parameter

values come from?

Were any difficulties encountered in finding and

applying the appropriate analytical solution?







Protocol Sheet

8.3.4 PROTOCOL SHEET 3.4: Rock Mass Classification

The analytical methods considered in Protocol Sheet 3.3 are in the top row in Figure 8.1, i.e.,

1:1 mapping, because there is an attempt to model the exact geometry in question—a circular

opening in the case of the Kirsch solution. However, in the case of rock mass classification, the

values of several rock mass parameters are reduced to index values from which an overall rock

mass classification value is established. This value then indicates the quality of the rock from

25

which decisions can be made regarding excavation and support. Thus, rock mass classification

is a non 1:1 mapping method because there is no direct attempt to incorporate the engineering

geometry into the rock mass classification value.

PROTOCOL SHEET 3.4

Rock Mass Classification

Why was the rock mass classification approach used?

Which type of rock mass classification method is being used?

Is the method(s) a standard one or is it a new one specially

developed for the project, or a modification of a standard

method?

If it is not a standard rock mass classification method, explain

the motivation for its use and its content

How is/are the rock mass classification value(s) to be used?

Have the engineers been trained in obtaining the rock mass

classification values? If so, how?

Has there been any check on the variability of the rock mass

classification values, e.g., the standard deviation of values?

Is there any check on the rock mass classification results and

implications using another modelling method, e.g. numerical

modelling?

Since the rock mass classification method is not 1:1 mapping,

how have you incorporated other factors, e.g., the presence of

a nearby fault?

Have any difficulties been encountered in using the rock mass

classification method?

Where is the rock mass classification information held?


26

Give the name of the person checking the contents of the

completed sheet



Location of back-up electronic storage of this Protocol Sheet

8.3.5 PROTOCOL SHEET 3.5: Basic Numerical Models

The basic numerical methods include the Finite Element Method, Boundary Element Method,

and Discrete/Distinct Element Method. These are classed as 1:1 methods because there is an

attempt to simulate the engineering geometry. Usually, the known larger fractures, e.g., faults

can be input into the mesh geometry as deterministic features but the smaller fractures are

simulated statistically via probability distribution functions. This Protocol Sheet 3.5 covers the

general use of numerical models; those with more advanced features, such as thermo-hydro-

mechanical couplings, are dealt with in Protocol Sheet 3.7.

PROTOCOL SHEET 3.5

Basic Numerical Models

Why was a numerical model used?

Which type of numerical model was used?

Why was that type of numerical model chosen?

How were the values of input parameters chosen?

Were the results from two different codes compared

to check if similar results were obtained?

Was a sensitivity study conducted, i.e., how

variations in the input parameters affected the

output parameters?

How were the factors of rock discontinuities,

27

inhomogeneity, anisotropy and time dependency

taken into account?


estimating the rock mass properties?

How was the presence of faults taken into account?

Has there been any way of validating the numerical

output, i.e., being able to check that the model

correctly represents the behaviour of the real rock?

Location of the numerical modelling information?







Protocol Sheet

8.3.6 PROTOCOL SHEET 3.6: Database and Systems Approaches

This approach is a more extensive version of the Precedent Type Analysis and Rock Mass

Classification, but is still a non 1:1 mapping method because the exact geometry of the project

is not mapped directly. The many variables in the system are studied, together with their

interactions, so that the most important components can then be identified, both with regard to

their importance and their hazard significance. Decisions on design can then be made on the

basis of this information, often supported by database information on rock engineering projects.

PROTOCOL SHEET 3.6

Database and Systems Approaches

28

Why was a database/systems approach used?

Which type of database/systems approach was

used?

How were the key project components identified?

Were these components ranked in terms of their

importance for the project?

Was a hazard analysis conducted based on the

identification of the most important parameters?

Was the significance of changes in parameters

studied, i.e., parameter A affects parameter B which

affects Parameter C, etc.?

Which specific database was used?

Have any difficulties been encountered in using the

database/systems approach?

Where is the database/systems information held?







Protocol Sheet

29

8.3.7 PROTOCOL SHEET 3.7: Extended Numerical Models

This subject covers extensions to the ‘conventional’ numerical methods, especially the use of

coupling algorithms to incorporate interactions between the primary variables, e.g., thermo-

mechanical coupling and hydro-mechanical coupling. More advanced extensions, such as full

thermo-hydro-mechanico-chemical (THMC) coupling are included and other features that make

the method advanced or specialised in some way.

PROTOCOL SHEET 3.7

Extended Numerical Models

Which type of extended numerical model has been

used?

Has this extended model been obtained ‘off the

shelf’, or has it been developed ‘in house’?

What are the special features of the extended model

being used?

How have the necessary input parameters been

obtained?



characteristics/parameters?

Has it been possible to check the output with another

modelling method, numerical or otherwise?

Has it been possible to validate the output of the

model, i.e., check that it correctly represents the real

rock behaviour?

Where is the information on the modelling

parameters and use of the extended numerical model

held?


30






Protocol Sheet

8.3.8 PROTOCOL SHEET 3.8: Advanced Systems Approaches

This Protocol Sheet covers methods more advanced than those covered in Protocol Sheet 3.6

and includes advanced systems approaches, internet-based systems approaches, virtual

computing platforms, use of real-time site data from instruments, TV images, etc.

PROTOCOL SHEET 3.8

Advanced Systems Approaches

Why is an advanced systems approach being used?

What type of advanced systems approach is being

used?

Explain how the data are being obtained

Explain how the data are being processed

Explain how the modelling output is being generated

Has it been possible to compare the results of the

advanced systems approach with any other

modelling method?



characteristics/parameters and processing the data?

31

Where is the information on the use of the advanced

systems approach being held?







Protocol Sheet

8.3.9 PROTOCOL SHEET 3.9: Alternative Type(s) of Modelling

The previous eight Protocol Sheets have covered the eight basic modelling methods shown

within the Protocol Sheet 3 rectangle in Figure 8.1. It is possible that some other type of

modelling method may be considered or have been used, e.g., physical modelling. This Protocol

Sheet 3.9 covers that eventuality.

PROTOCOL SHEET 3.9

Alternative Type(s) of Modelling

Why was an alternative modelling method used?

What type of alternative modelling method was

used?

Was it a 1:1 mapping or non-1:1 mapping model?

If it was a physical model, what type of physical

model was used?

Has total dimensional similarity been achieved?

32

If it was not a physical model, what type of

alternative model was used?

Explain the mode of operation of this alternative

model

Has it been possible to check the results of the

alternative model with any of the other methods

outlined in the Protocol Sheet 3 rectangle in Figure

8.1 in this book (Feng and Hudson, 2011)?

Were any difficulties encountered in the use of the

alternative model?

Where is the information on the use of the

alternative model held?







Protocol Sheet

8.3.10 PROTOCOL SHEET 3.10: Use of Different Modelling Methods in Combination or

Sequence

Often more than one modelling method is used to support the design of a rock engineering

project, i.e., two or more of the eight methods shown within the Protocol Sheet 3 rectangle in

Figure 8.1 may be used. These methods could be used in combination, e.g., the analytical and

rock mass classification approaches used together so that the results can be compared.

Alternatively, the methods could be used in sequence, e.g., an analytical method solution is used

33

to calibrate a basic numerical method, which is then extended to account for a particular feature

of the rock engineering project, such as the elevated temperature.

PROTOCOL SHEET 3.10

Use of Different Methods in Combination or Sequence

Why was it necessary to use more than one of the

modelling methods?

Which modelling methods were used?

Were these methods used in combination for

comparison of results or were they used in sequence

for a particular purpose?

Explain the overall results of using more than two

methods

Were any difficulties encountered in using two or

more or the modelling approaches?

Where is the information on the multiple use of

modelling methods held?







Protocol Sheet

34

8.4 PROTOCOL SHEETS 4: Design

Figure 8.2 below is the flowchart for design which was presented in Chapter 3, Figure 3.12,

(and is the companion to Figure 8.1 for modelling already included in Chapter 2, Figure 2.1).

The location in the Figure of Protocol Sheets 1-4 is indicated. Now we consider the Protocol

Sheets 4.1 and 4.2 dealing with the initial design and the final design, respectively. Note that

Protocol Sheet 4.2 also includes integration of all the modelling results, feedback obtained

during the construction process and the associated back-analysis.

Figure 8.2. The seven steps in the design process and the related Protocol Sheets.

It is possible to go directly from Step 5 to Step 7 in Figure 8.2, i.e., taking the initial design

(Protocol Sheet 4.1) as being the final design, but the inclusion of Protocol Sheet 4.2 allows for

the feedback loop accounting for information from construction—which may be traversed

Protocol Sheet 1

Protocol Sheets 2

Protocol Sheets 3

Protocol Sheets 4

7. Final design and verification

6. Integrated modelling and

feedback information

5. Establish initial design

4. Choose modelling method and appropriate

code

3. Design approach strategy

2. Key features of the site, rock

mass and project

1. Project purpose

Establish the objective and sub-objectives of the project

Identify the features and constraints of the site

rock mass and projectDevelop the overall design approach strategy based on the options in the

Methods A to D in the Figure 2.1 flowchart

Utilise the principles of modelling,

choose method(s)

Utilise the principles of code

implementation, choose method(s)

Establish initial design, conduct hazard assessment, and initiate construction, with

monitoring

Consider the integration of the

modelling methods in Figure 2.1

Consider feedback information from

construction, as in Fig.2.1, leading to closed-loop design

INITIAL DESIGN

FINAL DESIGN

DESIGN STEP CONTENTS OF THE DESIGN STEP

Establish final design and verify by monitoring

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several times as successively more and more construction related information becomes

available.

8.4.1 PROTOCOL SHEET 4.1: Initial Design

This Protocol Sheet covers Step 5 in Figure 8.2: the initial design. The decision may be taken

that the initial design is the final design; alternatively, Steps 6 and 7 may also be implemented,

leading to the final design which means that Protocol Sheet 4.2 is also required.

PROTOCOL SHEET 4.1

Initial Design

Has an initial design been established?

If so, what has been the main information leading to

the initial design?

Has there been appropriate integration of the

objective, the geological and site information and

the modelling?

What have been the key project factors affecting the

initial design?

What have been the key features of the site

affecting the initial design?

What have been the key modelling conclusions

affecting the initial design?

Has a hazard assessment been conducted and, if so,

what type?

Has monitoring been installed so that feedback

information will be available and back analysis then

possible?

Is the initial design flexible in the sense that

36

changes can be made?

Were any problems encountered in establishing the

initial design?

If it is decided that the initial design is the final

design, for what reasons was that decision made?







Protocol Sheet

8.4.2 PROTOCOL SHEET 4.2: Final Design

This Protocol Sheet 4.2 is used if modifications to the initial design lead to the final design.

PROTOCOL SHEET 4.2

Final Design

Why was the initial design modified to the final

design?

What has been the main type of information causing

the change to the final design?

If monitoring information during construction has

caused alteration to the initial design, which specific

data caused the change?

Has new modelling (via a back analysis) been

37

conducted as a result of the information obtained

during construction?

How many iterations of the loop indicated in Figure

8.2 (i.e., Steps 6 to 7 and 7 to 6 forming a feedback

loop) have been carried out?

How did you know when to stop the Steps 6 to 7

and 7 to 6 feedback loop and establish the final

design?

Has a new hazard assessment been conducted as a

result of the monitored information and, if so, of

what type?

Were any problems encountered in establishing the

final design?







Protocol Sheet

8.5 PROTOCOL SHEET 5: Auditing Evaluation

As mentioned earlier, the technical auditing requirement is

- to evaluate the logic of the work based on the stated objective,

- to establish whether all the necessary physical mechanisms, variables, and parameters

have been included in the relevant analyses,

38

- to show that the supporting analyses are technically correct,

- to consider whether conclusions are justified in terms of the project objectives and the

work conducted, and

- to provide an information, analysis and decision audit trail.

The purpose of the Protocol Sheets 1–4, together with their sub-sheets, now becomes

apparent: there is an audit trail explaining how and why all the major activities have been

conducted. From this, all the required items 1–5 in the list above have been satisfied.

Additionally, in Chapter 5 it was explained that the auditing can be ‘soft’, ‘semi-hard’ or

‘hard’, as indicated in Figure 8.3. The Protocol Sheets included so far certainly provide the basic

information necessary for establishing the essence of the problem in the ‘soft’ audit and, if the

necessary supporting information is included or referenced with the completed Protocol Sheets,

also satisfy the requirement for the ‘hard’ audit.

Protocol Sheets 5

Soft Audit Semi-Hard Audit Hard Audit

Checking that the basic approach to the design problem and

the associated modelling follow

appropriate principles

Checking that the basic approach to the design

problem and the associated modelling,plus the key details,

follow appropriate principles

Checking that all aspects with all the

relevant details have been appropriately

implemented

AUDIT EVALUATIONThe evaluation will depend on the type of auditing used,

‘soft’, ‘semi-hard’, or ’hard’, and whether a single audit has been usedor a progression through the three auditing types

39

Figure 8.3. The ‘soft’, ‘semi-hard’ and ‘hard’ audits, and the audit evaluation.

What remains now is to evaluate this audit information to ensure that the information

gathered, the modelling work and the initial/final rock design are adequate for the purpose, see

the final box in Figure 8.3.

PROTOCOL SHEET 5

Auditing Evaluation

Is this auditing evaluation being made as a ‘soft’,

‘semi-soft’ or ‘hard’ audit (see Figure 8.3)

Has it been assured that all the information in all the

completed Protocol Sheets is correct?

Is the quantity of information in all the Protocol

Sheets acceptable* — in the sense that there is

sufficient information (either directly or through the

referenced material) for the audit evaluation to be

completed? If not, specify where there is

insufficient information.

*This refers to the information itself, not to the evaluation

of the information

Can you recommend how this lack of sufficient

information can be overcome?

Does this auditing evaluation indicate that all

aspects of the work (as described in the Protocol

Sheets) are acceptable? If not, indicate where there

are problems

Can you recommend how these problems should be

overcome?

40

Were any difficulties encountered in undertaking

this auditing evaluation?

Is this Auditing Evaluation Protocol Sheet being

completed by a person who has an independent

status, and is free of investigatory and reporting

constraints? If not, explain where there could be a

conflict of interest







Protocol Sheet

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