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Iron Ore Technical Working Group Submission for Evaluation and

Verification

‘Terms of Reference 1’

Consider the adequacy of current methods for determining transportable moisture limit (TML) for iron ore fines and consider new and/or amended existing methods to be

included in Appendix 2 of the IMSBC Code.’

February 15, 2013

All participants of the TWG operate under the international and their respective national antitrust laws and regulations. Suitable controls are in place to ensure all meetings are

minuted and discussions and material exchanged do not transgress anti-trust requirements. All participants of the Technical Working Group have access to in-house

competition law advice, operate at all times under all applicable international and national competition laws and regulations and have been cautioned accordingly.

Preamble

At the 17th session of the Sub-committee on Dangerous Goods, Solid Cargoes and Containers, Member States directed the Correspondence Group (CG) on the transportation of the iron ore fines (established at DSC 16) to continue its work with updated Terms of Reference to:

.1) consider the adequacy of current methods for determining transportable moisture limit (TML) for iron ore fines and consider new and/or amended existing methods to be included in appendix 2 of the IMSBC Code – to be completed by end of May 2013 (DSC 17/4/34 and DSC 17/INF.9);

.2) consider the evaluated and verified research into Iron Ore Fines – to be completed by end of May 2013;

.3) prepare draft individual schedule(s) for iron ore fines and any required amendments to appendix 2, taking into account .1 and .2 above and review the existing iron ore schedule, as necessary; and

.4) submit a report to DSC 18.

In an effort to ensure the CG’s deliberations are informed by the latest scientific insights, the three largest iron ore producers (with the support of their respective Competent Authorities) committed to form an Iron Ore Technical Working Group (TWG). The TWG is coordinating research efforts into the transportation of iron ore fines to provide independently “evaluated and verified” findings that can serve as the basis for decision making.

To this end, the TWG will produce the following reports:

Report #1: “Terms of Reference .1” – This report assesses the adequacy of current IMSBC Code methods for determining the Transportable Moisture Limit (TML) of Iron Ore Fines (IOF).

Report #2: “Marine Studies” – This document reports the characteristics of vessel motions and forces imposed on IOF cargoes during transit; the impacts of vessel size and sea conditions (swell, sea and wind); and, the stability of vessels in various cargo behaviour scenarios.

Report #3: “Routine Test Method”– Building on the outcomes of Report #1, this document explores potential adjustments to one of the existing routine IOF test methods – or a new test – to better reflect actual in-hold shipping conditions and observations.

Report #4: Reference Tests – This report provides further evidence to substantiate the applicability of the routine IOF test method identified in Report #3 through the material’s performance in real-world conditions using a variety of well-established geotechnical methods, numerical modelling and cargo observation.

Report #5: Final Submission – This report will integrate the results of all of the preceding research into a series of recommendations that can inform the deliberations of the Correspondence Group.

The TWG have appointed external experts in the relevant disciplines to verify each of the reports. This evaluation is followed by an independent scientific review process undertaken by Imperial College of London, under the direction of

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the International Group of P&I Clubs (IG). IG represents a group of industry NGOs that includes BIMCO, Intercargo, International Chamber of Shipping and IFAN. The finalized reports are then submitted to the CG, fulfilling the requirement for “evaluated and verified” research.

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Executive summary

The Technical Working Group (TWG), comprising one Brazilian and two Australian mining companies, undertook a literature review and practical applied research to assess the suitability of current methods outlined in the International Maritime Solid Bulk Cargoes Code (IMSBC Code) for determining the Transportable Moisture Limit (TML) of Iron Ore Fines (IOF). This document responds, in part, to the terms of reference of the Correspondence Group (CG) established by the IMO Sub-Committee on Dangerous Goods, Solid Cargoes and Containers (DSC) at its seventeenth session. The relevant section of the terms of reference is:

‘Consider the adequacy of current methods for determining transportable moisture limit (TML) for iron ore fines and consider new and/or amended existing methods to be included in appendix 2 of the IMSBC Code.’

The report contains the outcomes of the TWG research on the three current TML methods contained in the IMSBC Code and sets out the advantages and disadvantages of each when used for IOF. This report makes no inferences for other solid bulk cargoes.

The key findings of the research are:

1. Each of the tests - Flow Table Test (FTT), Penetration Test (PT) and Proctor-Fagerberg Test (PFT) – are not a direct measurement of the liquefaction potential of solid bulk cargoes. The tests do not take into account key material properties of a cargo (e.g., dilatency, degree of saturation) or system variables (e.g., pore water pressure, vessel motion) that can influence liquefaction potential.

2. The three IMSBC TML tests have limitations in their applicability to IOF.

3. The PT and the FTT give TML results that are more variable than the PFT, despite testing identical samples under the same conditions. Both are highly operator dependent, as well as requiring test equipment which is not as simple as that of the Proctor-Fagerberg test.

4. PFT is the most objective test, producing the lowest variability of the three methods. When compared to FTT and PT, PFT produces higher TML results. These are influenced primarily by particle size distribution and compaction energy.

5. The issues related to the PFT suitability as prescribed in the IMSBC Code for IOF are:

The Optimum Moisture Content (OMC) of IOF differs from the OMC of the specific mineral concentrates that were originally used by

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Fagerberg to develop the test as it exists within the IMSBC Code (i.e., the OMC of IOF is 90-95% versus 70-75% in the Scandinavian ores and concentrates studied by Fagerberg). This suggests an important discrepancy between the 70% standard in the IMSBC Code and what has been observed in the research for IOF.

Similarly, the compaction energy requirements established as starting conditions for the PFT do not match real-world conditions of the cargo once loaded (i.e., bulk density).

Determination of the TML provides an early indicator in the chain of events that might lead to liquefaction and ship instability, but the TML on its own is not definitive in this regard. While the TML is, from a safety view point, an appropriate measurement to use, it does not follow that all ships where the moisture content of the cargo exceeds the TML will experience stability problems or even any liquefaction of cargo. Accordingly, the TML is an important indicator with an in-built safety margin.

The test methods, as prescribed in the IMSBC Code, are able to determine a TML value but have limitations in their applicability for IOF. Of the three tests the PFT has the most potential to be recalibrated for IOF. Therefore, further research is being undertaken to calibrate the PFT to real-world conditions ensuring adequacy. This will be covered in Reports 2-4.

It is important to note that the TWG’s research is focused exclusively on IOF and that the findings are not intended to infer applicability to other cargoes.

The TWG’s research covers the entire range of iron ore mineralogy, providing a comprehensive picture of iron ore behaviour in seaborne transportation. Similarly, the vessels studied range from Handysize to Capesize.

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Contents

Contents 6List of Tables and Figures 8

Abbreviations 11

Section 1 – Introduction 12

Section 2 – Review of Existing IMSBC TML Methodologies 132.1 Flow Table Test (FTT) 13

2.2 Penetration Test (PT) 16

2.3 Proctor-Fagerberg Test (PFT) 17

2.4 Conclusion 21

Section 3 – TWG Research Results of Current TML Methods 233.1 Flow Table Test 23

3.1.1The maximum particle size of the sample has a first order impact on the estimated TML values. Smaller particle top sizes increase the TML. 23

3.1.2 A minimum of 30 minutes soaking time is essential, in order for the water to be absorbed into the ore particles and within the micropores. 26

3.1.3 Tamping technique and interpretation of the Flow Moisture Point affects the determination of TML 29

3.1.4 TML variability exists under the same testing conditions. 32

3.2 Penetration Test (PT) 33

3.2.1 The TML is influenced by variation in tamping pressure and acceleration force. 33

3.2.2 Brass bit penetration depth is sensitive to small increments of moisture, leading to inconsistent results. 36

3.2.3 There is significant variability in bit penetration depths. 38

3.3 Proctor-Fagerberg Test (PFT) 40

3.3.1 The compaction energy with the Standard Proctor C 350g hammer produces dry bulk densities higher than those measured at loading. 40

3.3.2 The OMP of the IOF tested occurs between 90-95% saturation. 43

3.3.3 TML precision is deemed satisfactory when a testing method is consistently applied. 45

3.3.4 The TML increases when material is screened. 47

3.4 Collective Findings 49

3.4.1 For all IOF material tested the PT produced the lowest TML of the three methods, followed by FTT then PFT. 49

3.4.2 The PFT demonstrated the highest precision out of the three methods, followed by the PT then FTT. 51

3.4.3 Mixing technique should be done by non-mechanical bag mixing. 52

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3.4.4 TML results align between the PFT and FTT at lower PSD with screening. 56

Conclusions & Recommendations 58

References 60References - Flow Table Test (FTT): 60

References - Penetration Test (PT) 60

References - Proctor Fagerberg (PF) 61

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List of Tables and Figures

Table 1: Pros and Cons for Flow Table Test...................................................................15

Table 2: Pros and Cons for Penetration Test...................................................................17

Table 3: Pros and Cons for Proctor Fagerberg Test........................................................20

Figure 1: Example of a Proctor-Fagerberg compaction curve.........................................18

Figure 2: TML increases with reducing top size fraction using a 20 kgf tamping force (Sample of Australian Iron Ore Fines: Australia – A).........................................24

Figure 3: TML increases with reducing top size fraction (Sample of Australian Iron Ore Fines: Australia – B)..........................................................................................24

Figure 4: TML increases with reducing top size fraction (7 different samples of Brazilian Iron Ore Fines: IOF Brazil 1 to 7)......................................................................25

Figure 5: A coarse sample from Australian Iron Ore Fines: Australia – A, that failed the FTT (Note: this sample produced a TML on the PFT).......................................25

Figure 6: Variation in soaking time from 5 minutes to 36 hours - Sample of Australian Iron Ore Fines: Australia – A....................................................................................26

Figure 7: Variation in Equilibration time (Sample of Australian Iron Ore Fines: Australian – B)................................................................................................................... 27

Figure 8: Variation in Equilibration time (Brazilian Ores).................................................27

Figure 9: Inconsistent TML results occur when the tamping force is increased to 40kgf (Sample of Australian Iron Ore Fines: Australia – A).........................................29

Figure 10: Variable FTT results when completed on the same sample but with a different operator (Sample of Australian Iron Ore Fines: Australia – B)..........................30

Figure 11: Variable FTT results when completed on the same sample but at different laboratories/operator (Brazilian Iron Ore Fines)................................................30

Figure 12: Box plot showing minimum, maximum and median value at a single operating condition (Sample of Australian Iron Ore Fines: Australia – A).........................32

Figure 13: The average TML increases with decreasing tamping force at 2G acceleration and 25 tamps per layer ( Sample of Australian Iron Ore Fines: Australia – A). .34

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Figure 14: Discrete tests in non-consecutive manner using a tamping force of 30 kgf and an acceleration of 1.5 G gives an increased TML compared to a higher acceleration of 2.5 G Sample of Australian Iron Ore Fines: Australia – A.........34

Figure 15: Discrete tests in non-consecutive manner using a tamping force of 20 kgf and an acceleration of 1.5 G gives an increased TML compared to a higher acceleration of 2.5 G ( Sample of Australian Iron Ore Fines: Australia – A).....35

Figure 16: Using a tamping force of 10 kgf and an acceleration of 1.5 G gives an increased TML (Sample of Australian Iron Ore Fines: Australia – A)................35

Figure 17: The brass bit penetration is sensitive to moisture increments Sample of Australian Iron Ore Fines: Australia – A............................................................37

Figure 18: Statistical summary of the differences in bit penetration for the PT (Sample from Australian Iron Ore Fines: Australia - B)...................................................38

Figure 19: The effect of bit position relative to penetration depth - Sample of Australian Iron Ore Fines: Australia - B..............................................................................39

Figure 20: The average bulk density at loading (red dots/line) demonstrates corresponding void ratios that are higher than those for the Proctor C 350g hammer (Sample of Australian Iron Ore Fines: Australia – A)..........................41

Figure 21: The average bulk density at loading (red dots/line) demonstrates corresponding void ratios that are higher than those for the Proctor C 350g hammer (Sample of Australian Iron Ore Fines: Australia – B)..........................41

Figure 22: The average bulk density at loading (red dot) demonstrates corresponding void ratios that are higher than those for the Proctor C 350g hammer (Sample of Brazilian Iron Ore Fines)...................................................................................42

Figure 23: The Optimum Moisture Points between 95 and 98% (Multiple samples of Australian Iron Ore Fines: Australia – A)...........................................................43

Figure 24: The Optimum Moisture Points between 90 and 96% (Multiple samples of Australian Iron Ore Fines ‘Australia – B’)..........................................................44

Figure 25: The Optimum Moisture Point at 91% for a sample of Brazilian Iron Ore Fines........................................................................................................................... 44

Figure 26: Comparative results of PF tests between an external laboratory and the laboratory of an Australian Iron Ore Fines producer.........................................45

Figure 27: Comparative results of PF tests between an external laboratory and the laboratory of a Brazilian iron ore fines producer................................................46

Figure 28: PFT TML absolute differences between duplicates for Brazilian Iron Ore Fines.................................................................................................................46

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Figure 29: The impact of screening Brazilian impacts the TML and is reflective of the fine PSD of the material...........................................................................................47

Figure 30: The TML increases by 0.5% when the top size fraction is reduced from 10 mm to 5 mm Samples of Australian Iron Ore Fines: Australia – A...........................48

Figure 31: Screening of samples impacts TML results when using PFT. A lower TML is achieved when including the entire PSD for Samples of Australian Iron Ore Fines: Australia – B...........................................................................................48

Figure 32: TML test type base case comparisons showing the difference in results for the three methods and the variation in standard error for Australian Iron Ore Fines ‘Australia – A’.....................................................................................................50

Figure 33: TML test type base case comparisons showing the difference in results for the three methods for Australian Iron Ore Fines ‘Australia – B’...............................50

Figure 34: TML test type base case comparisons showing the difference in results for the three methods for Brazilian IOF.........................................................................51

Figure 35: Precision for the PFT and FTT on Australian Iron Ore Fines ‘Australia – B’...52

Figure 36: Particle degradation as a result of using the planetary mixer.........................53

Figure 37: Visual observation of particles after using a cement mixer.............................54

Figure 38: HDPE bag mixing method..............................................................................54

Figure 39: PFT results from using the bag mixing method with multiple operators.........55

Figure 40: PFT results from using the various mixing techniques with multiple operators.......................................................................................................................... 56

Figure 41: Comparison of the PFT and FTT of duplicate samples and the impact of screening. The TML values for the two methods align as the PSD is reduced by screening..........................................................................................................57

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Abbreviations

ASTM American Society for Testing and Materials

CG Correspondence Group

DSC Dangerous Goods, Solid Cargoes and Containers

FMP Flow Moisture Point

FTT Flow Table Test

G The measurement of force due to acceleration or gravity

Hz Hertz

IMCO Inter-Governmental Maritime Consultative Organization (precursor to the IMO)

IOF Iron Ore Fines

IMO International Maritime Organization

IMSBC Code International Maritime Solid Bulk Cargo Code

kgf Kilograms of force

OMC Optimum Moisture Content – see also OMP

OMP Optimum Moisture Point

PFT Proctor-Fagerberg Test

PSD Particle Size Distribution

PT Penetration Test

TML Transportable Moisture Limit

TOR Terms of Reference

TWG Technical Working Group

X + X is nominal % moisture value to allow scalability but preserve masking of data to fulfil internal anti-trust requirements.

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Section 1 – Introduction

The Technical Working Group (TWG), comprising one Brazilian and two

Australian mining companies, has undertaken a program of research on

representative Australian and Brazilian Iron Ore Fines (IOF) materials to assess

the suitability of current methods in determining the Transportable Moisture Limit

(TML), as outlined within the International Maritime Solid Bulk Cargoes Code

(IMSBC Code).

The research was predominantly undertaken prior to the 17th meeting of the

Sub-Committee on Dangerous Goods, Solid Cargoes and Containers which

established ‘Terms of Reference’ (TOR) for a Correspondence Group on the

transportation of IOF. This report responds to TOR1, which directs the

Correspondence Group to:

‘Consider the adequacy of current methods for determining transportable moisture limit (TML) for iron ore fines and consider new and/or amended existing methods to be included in appendix 2 of the IMSBC Code.’

This report contains the outcomes of the TWG research reviewing the three

current TML methods contained within the IMSBC Code, and their applicability

for IOF. These three methods are:

Flow Table Test (FTT)

Penetration Test (PT)

Proctor-Fagerberg Test (PFT)

The research into new or amended methods is an outcome of the ongoing

scientific effort being conducted by the TWG and is outside the scope of this

paper. The primary objectives of this submission are to describe the results of:

A literature review of the existing tests to establish context.

Laboratory testing and other research to determine the suitability of the

existing tests and their application to IOF.

The research based on measurement and fact over subjective arguments.

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Section 2 – Review of Existing IMSBC TML Methodologies

A literature review to capture the key aspects of each of the three Transportable

Moisture Limit (TML) test methods contained in the IMSBC Code is summarized

below. These aspects have been explored further in direct research by the TWG

with findings presented in the next section.

2.1 Flow Table Test (FTT)

The FTT was originally recommended in the Canadian Concentrates Code in the

early 1960s. It was adopted in the Inter-Governmental Maritime Consultative

Organization (IMCO) Code in the 1980s and has been a standard test for

decades for the determination of the flow moisture point of materials (Fagerberg

et al., 1971; Kirby et al., 1981). A similar test is used in civil engineering for

hydraulic cement (American Society for Testing and Materials (ASTM) Section

C230). It is applicable for mineral concentrates with maximum particle top size of

1mm and can possibly be used for a maximum size of up to 7mm. The FTT is a

relatively simple test with little interpretation of test data required. The critical

aspect is the reliable identification of a flow state in the test sample using the

criteria given in the IMSBC Code (Section 1.1.1).

This test uses a mould placed on a horizontal steel plate. The sample is

compacted into the mould, which is then removed, and the sample and its

supporting table are rotated and dropped repeatedly. The plate is dropped from a

height of 12.5mm at a rate of 25 drops per minute for two minutes. The behaviour

of the sample is observed to discern between crumbling and plastic deformation.

The water content at which the sample exhibits flow characteristics is deemed

the flow moisture point (FMP) 1. The TML is defined as 90% of the moisture

content at the FMP (IMO, 2009). It is noted in Green and Kirby (1981) that the

1 The flow moisture point is the maximum water content, expressed as a percentage, at which a sample of cargo will begin to lose shear strength. Cargoes with moisture content beyond flow moisture point may be liable to liquefy, (Loss Prevention Briefing for North of England Members, March 2010).

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10% safety margin is inadequate to cover errors associated with sampling,

reliability and testing. This, together with uncertainties in the testing procedure

and in establishing the point at which the sample exhibits “flow deformation

instead of cracking”, leads to questions regarding the reasonableness of the test.

The main issue, however associated with the FTT is that the FMP is assessed

visually, making it heavily dependent on the judgement of the operator. The loss

of shear strength, identification of plasticity, and the subsequent FMP is based on

the subjective determination of the operator (Fagerberg et al., 1971; Kvalheim et

al., 1971). A study performed by the Institute of Industrial Science in Tokyo noted

that although the FTT is widely recognised, its “reliability is not adequate since

the resulting value depends on the ability of the operator” (Ura, 1995).

The issues associated with the FTT methodology and FMP determination led to

the investigation and development of alternative testing procedures.

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Pros Cons

Most widely used test in the industry ( Green & Kirby 1981).

The FTT is a relatively simple test, requiring little test data interpretation

Plastic flow state can be visually observed.

Applicable for mineral concentrates with max. size of 1mm, although can possibly be used for max. size of up to 7mm (IMSBC Section 1.1.1).

Method is subjective.

In certain circumstances, internal stress state and confining pressure are lost from the analysis:“…it is widely recognized that its reliability is not adequate since the resulting value considerably depends on the ability of the operator.” (URA, Tamaki Institute of Industrial Science, University of Tokyo, 1995).

Determination of the FMP is open to the discretion of the operator: “Another disadvantage with the flow table test is that the flow moisture point is assessed visually and not determined by means of measurable quantities. This requires skill and care. The flow table has also proved unsuitable for coarse concentrates since the moulded material collapses through lack of initial granular cohesion.” (Fagerberg, B., Stavang, A., “Determination of Critical Moisture Contents in Ore Concentrates Carried in Cargo Vessels,” Minerals Transportation, 1971).

Table 1: Pros and Cons for Flow Table Test

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2.2 Penetration Test (PT)

The Penetration Test (PT) was developed in Japan as an alternative to the FTT

that was less dependent on operator input and could accommodate larger sized

particles (Green & Hughes, 1977; IMO, 1988). Although the method was

developed initially for coal, the research team conducted work on other

commodity concentrates, concluding that “the method is applicable to a wide

variety of materials.” (Ura, 1995). The method has not, however, been widely

adopted for TML determination outside of the coal shipping industry.

The PT is based on the principle that there is a direct relationship between loss of

shear strength by cyclic vibration and liquefaction. The test is performed by

placing a sample in a cylindrical container and then tamped as per the FTT

method. It is then subjected to cyclic vibrations of 2G±10% at 50 or 60Hz via a

vibrating table. A weight, in the form of a penetration bit, is placed on top of the

sample. The sinking of the penetration bit is taken as an indication of the loss of

shear strength by the sample. Penetration greater than 50mm implies

liquefaction. The measured water content of the sample at this point is

determined to be the FMP. The TML is then calculated as 90% of the FMP.

The PT equipment is the most sophisticated apparatus of the three methods and

has advantages with coarser Particle Size Distribution (PSD) up to 25mm. The

issues with the test, however, are that the 2G vibrational loading has no

calibration to accelerations and forces generated by vessel motion (Eckersly,

1997). In addition, the equipment, although sophisticated, is sensitive to set up,

isn’t portable and is subject to equipment stress/failure when in operation.

Pros Cons

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Applicable for materials with max. size of up to 25mm.

Estimation of TML with this method is more objective than subjective.

Easy to interpret data (i.e., bit exceeds 50mm or not).

Sophisticated test equipment required with sensitive controls.

The testing equipment/apparatus is non-portable, needing to be bolted to a floor.

Vibrational loading has no real relation with actual ship forces. “... these test conditions, their types of motion, vibration amplitudes and frequencies are not necessarily the same as occur in ships’ cargoes. There seems to be little information that relates measured FMP’s, shipping moisture contents and measured ship motions to observed behaviour of actual cargoes.” (Eckersly, J D., “Coal Cargo Stability” The AusIMM Proceedings, 1997).

Table 2: Pros and Cons for Penetration Test

2.3 Proctor-Fagerberg Test (PFT)

The PFT procedure determines the TML of a cargo as equal to the critical

moisture content at optimum degree of saturation, which is fixed at 70% in the

IMSBC Code. The test method, supported by the initial work undertaken by

Proctor in the 1930s, was enhanced in 1965 by Fagerberg. It differs from the

other IMSBC Code test methods in that it does not rely on the identification of a

flow state or a point deemed as the threshold of liquefaction, the FMP. Most of

the work undertaken by Fagerberg in this field was in bulk ore and mineral

concentrates. (Fagerberg, 1965a and 1965b).

The PFT is a dynamic compaction laboratory test method, similar to the

compaction tests applied in geotechnical or soil mechanics science, where the

equipment and procedures derive from those originally proposed by R. R. Proctor

in 1933 (apud ASTM D698 “Standard Test Methods for Laboratory Compaction

Characteristics of Soil Using Standard Effort (12 400 ft-lbf/ft3 (600 kN-m/m3)”,

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Engineering News Record, September 7, 1933). The standard effort test,

described in item 3.1.3 of ASTM D698, is often referred to as the Proctor Test.

The test uses a specific methodology for finding the Optimum Moisture Content

(OMC) for compaction of the material being tested, usually a soil. Compaction

curves are plotted, relating dry density and moisture content. From these curves,

the OMC can be identified at the point of maximum compaction (maximum dry

density) as shown in Figure 1. The OMC is also referred to as the Optimum

Moisture Point (OMP). In all cases, it corresponds to the minimum void ratio or

maximum compaction condition (i. e., maximum dry bulk density) for the given

compaction energy.

Figure 1: Example of a Proctor-Fagerberg compaction curve.

According to Proctor (1948, apud Puls, 2008), the equation below allows the

calculation of the compaction energy on single effort dynamic compaction tests,

such as the standard Proctor test itself or the IMSBC Code PFT.

E = Number of Blows per Layer x Number of Layers x Hammer Weight (N) x Height of Drop (m)Volume of Mold (m3)

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The equation variables are the hammer mass, drop height, number of material

layers inside the mould, number of blows per layer and volume of the mould.

Different compaction energies will produce different bulk densities at the same

moisture content. It is necessary to determine which energy value will produce

the correct compaction degree (i.e., the target bulk density at that which best

represents the bulk density achieved at cessation of loading).

When determining the TML using PFT, the IMSBC Code requires the TML of a

cargo to be taken as equal to the moisture content at 70% degree of saturation,

in all cases. The rationale of Fagerberg for the 70% degree of saturation for TML

is explained as follows: a “characteristic of all concentrates investigated is that

the voids at optimum compaction are filled at 70-75 per cent of volume by water,

the balance being air.” (Fagerberg, 1965; Fagerberg & Stavang, 1971).

Fagerberg correlated OMP to a safe carriage condition and not necessarily 70%

saturation. The 70% saturation was deemed as a limit for safe carriage only

because the materials then investigated by Fagerberg (Scandinavian ores) could

be “safely carried in a vessel if the calculated degree of saturation is below 70%.”

Fagerberg, 1965 and Fagerberg & Stavang, 1971 identified the OMP for the

materials investigated as being in the 70-75% saturation range. Furthermore,

70% was selected, as moisture migration was not expected to occur.

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Pros Cons

The technical background and concept behind the PF test methodology is based on sound geotechnical science and engineering practice (see Fagerberg, 1965).

Estimation of TML with this method is objective, not subjective. The results are not dependent upon the operator’s perception.

Very simple test equipment and procedure.

Good precision; consistent results.

Applicable for materials with maximum validated size of up to 5mm, or for coarser materials, with a top size greater than 5mm.“an extensive investigation for adoption and improvement is required.”(IMSBC Section 1.3.1).

The test is not applicable for porous materials (IMSBC Section 1.3.1.1)

Need basic soil mechanics knowledge to process and interpret results. Calculations may be complicated (IMSBC Section 1.3.4).

The TML result may be sensitive to the determination of the Specific Gravity (SG) value, and if so, may lead to erroneous results.

While not a limitation of the test itself, the IMSBC Code requirement that all cargo be tested at a critical moisture content of 70% degree of saturation for the purposes of the test does not take into account specific characteristics of various ores.

Table 3: Pros and Cons for Proctor Fagerberg Test

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2.4 Conclusion

Product moisture is currently the only product specification that, if exceeded,

does not allow Group A cargoes, as defined by the IMSBC Code, to be shipped.

The underlying philosophy is that potentially liquefiable materials are not likely to

liquefy if their moisture content is lower than a certain limit – the TML. The

IMSBC Code describes three laboratory test methods for estimating the TML

values for Group A bulk cargoes. These are: FTT; PFT; and PT. The FT and the

PFT were primarily developed to test metal ore concentrates, while the PT was

developed primarily for the coal industry.

These TML tests relate the liquefaction susceptibility of an on-board product to

only the product moisture content. In geotechnical earthquake science, moisture

content is only one of many important parameters that need to be considered in

the liquefaction susceptibility evaluation. In a broad sense, these parameters

could be grouped under two general headings:

Material Properties; and,

System Variables (conditions to which the material is subjected).

Dilatency (ability of a material to expand or contract when sheared), degree of

saturation, and hydraulic conductivity in relation to the rate of loading are the key

material properties that influence liquefaction. Moisture content, which is a weight

ratio, only has an indirect influence thorough degree of saturation, which is a

volumetric ratio, on liquefaction.

Under System Variables, parameters such as confining pressure (overburden

stress or pore water pressure), magnitude and rate of loading (ship motion), and

drainage conditions are parameters that can influence liquefaction. For example,

a product, with certain material properties, may not be liquefiable under certain

system variables but the same product with the same material properties when

subjected to a different set of system variables could very well be liquefiable.

The three TML test methods described in the IMSBC Code do not replicate

conditions that reasonably match actual ship hold conditions. The FTT requires

the sample to be compacted in a brass mould with a tamping pressure that only

loosely represents the maximum overburden stress in a ship hold. However,

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when the brass mould is removed prior to dropping the table, the lateral stress

state and confining pressure are totally lost. Moreover, the test is operator-

dependent and lacks objectivity.

In the PT, the density of the test sample, the magnitude, frequency, and duration

of cyclic loading, and the weight of the brass bit have no relevance to the actual

ship hold conditions.

Lastly, while the PFT relates the degree of saturation with the moisture content, it

does not properly account for ship motion/energy, and also falls short of

considering the dilatant versus contractive nature of the material.

Based on the above, it can be concluded that the three TML tests prescribed in

the Code are all tests that indirectly estimate the liquefaction susceptibility of a

potentially liquefiable cargo. All three tests assume that the material being tested

is potentially liquefiable and hence, by limiting the moisture content, the potential

for liquefaction of that material is reduced.

Date 8-May-23 of 62

Section 3 – TWG Research Results of Current TML Methods

The TWG undertook laboratory research to further examine the three tests

prescribed in the IMSBC Code in order to ascertain their application for

determining the liquefaction potential of iron ore fines.

3.1 Flow Table Test

The TWG has undertaken significant testing regarding the Flow Table Test. The

effects of particle top size, tamping pressure and material soaking time were all

aspects of the research work. The key findings are:

The maximum particle size of the sample has a first order impact on the

estimated TML values. Smaller particle top sizes increase the TML.

A minimum soak time of 30 minutes is required to allow for equilibration.

Tamping technique and interpretation of the Flow Moisture Point affects the

determination of TML.

TML variability under the same testing conditions is observed.

3.1.1The maximum particle size of the sample has a first order impact on the estimated TML values. Smaller particle top sizes increase the TML.

Samples were screened to determine if particle size distribution (PSD) has

an impact on the TML result. The results are seen in Figure 2 - Figure 4.

Date 8-May-23 of 62

Figure 2: TML increases with reducing top size fraction using a 20 kgf tamping force (Sample of Australian Iron Ore Fines: Australia – A)

Figure 3: TML increases with reducing top size fraction (Sample of Australian Iron Ore Fines: Australia – B)

Date 8-May-23 of 62

Figure 4: TML increases with reducing top size fraction (7 different samples of Brazilian Iron Ore Fines: IOF Brazil 1 to 7)

.

Figure 5: A coarse sample from Australian Iron Ore Fines: Australia – A, that failed the FTT (Note: this sample produced a TML on the PFT)

Date 8-May-23 of 62

The observations from this test work are:

The TML increased when the particle top size was reduced. This was the

case in all tests.

In the case of FTT, a coarser PSD may lead to premature failure of the

mould, resulting in a ‘no result’. Corresponding samples when tested with

the PFT produced a TML result (Figure 5).

3.1.2 A minimum of 30 minutes soaking time is essential, in order for the water to be absorbed into the ore particles and within the micropores.

Tests were established to review the impact of adding moisture to samples

and determining if there was significance in equilibration time in the result.

The tests were conducted over a range of Australian ores of varying

mineralogy and porosity. The outcomes of this work are seen in Figure 6 &

Figure 7.

Figure 7

Figure 6: Variation in soaking time from 5 minutes to 36 hours - Sample of Australian Iron Ore Fines: Australia – A

Date 8-May-23 of 62

Figure 7: Variation in Equilibration time (Sample of Australian Iron Ore Fines: Australian – B)

Figure 8: Variation in Equilibration time (Brazilian Ores)

Date 8-May-23 of 62


The test on Australian-A Iron Ore Fines shows that allowing the material to

soak for a minimum of 30 minutes is critical. A soaking time of 5 minutes

produced highly variable TML results. The short soaking time is not

sufficient to allow the water molecules to enter the micropores of the

material (Figure 6).

The test on Australian - B Iron Ore Fines demonstrates that a minimum of 1

hour equilibration time is required, with an ideal of 12 hours (Figure 7).

For the Brazilian Iron Ore Fines tested, the soaking time is not influential in

the determination of the FMP (Figure 8).

Depending on the mineralogical characteristics of the ore, soaking time may or

may not affect the TML. Nevertheless, it is recommended the material undergoes

minimal non-mechanized mixing and overnight soak in a sealed container/bag.

Date 8-May-23 of 62

3.1.3 Tamping technique and interpretation of the Flow Moisture Point affects the determination of TML

One focus of the research was to determine the major contributors to

variability in FTT results. The tamping technique (consistent application of

force and even coverage) and FMP interpretation were outcomes identified

as the key sources of variability.

Figure 9: Inconsistent TML results occur when the tamping force is increased to 40kgf (Sample of Australian Iron Ore Fines: Australia – A)

Date 8-May-23 of 62

Figure 10: Variable FTT results when completed on the same sample but with a different operator (Sample of Australian Iron Ore Fines: Australia – B)

1 2 3 4 55

6

7

8

9

External Lab Internal Lab

Flow

Tab

le T

ML (

%)

Figure 11: Variable FTT results when completed on the same sample but at different laboratories/operator (Brazilian Iron Ore Fines)

Date 8-May-23 of 62


The complexity of operating a spring-loaded device and maintaining 40kgf

pressure on the mould leads to inconsistent TML results (Figure 9).

Unlike results from Section 3.1.1, where reducing the particle top size

resulted in an increased TML, results at 40kgf are inconsistent. This may

be attributable to the variation of the material void ratio.

Variation between operators for the FTT on Australia - B IOF and Brazilian

IOF demonstrated that inconsistent tamping pressure and FMP

determination resulted in variability of TML values for the same sample of

up to 0.8% Figure 10 and 1% Figure 11.

Date 8-May-23 of 62

3.1.4 TML variability exists under the same testing conditions.

Triplicate tests were performed with a single operator under the same

testing conditions:

o As received -10 mm material

o Tamping pressure = 20 kgf

o Mixing time = 5 minutes

The TML varies from 9.96% to 10.26% as shown in Figure 12.

FTT results are generally lower and more variable than PFT results. (refer

to Section 3.4).

Figure 12: Box plot showing minimum, maximum and median value at a single operating condition (Sample of Australian Iron Ore Fines: Australia – A)

Date 8-May-23 of 62

3.2 Penetration Test (PT)

The TWG has undertaken testing regarding the Penetration Test. The effects of

tamping, accelerations, bit measurement and repeatability were all aspects of the

research work. The key findings of this work are:

The Penetration Test is sensitive to tamping pressure and acceleration.

Small moisture increments result in significant changes in penetration

depth.

There is significant variability in penetration depth.

3.2.1 The TML is influenced by variation in tamping pressure and acceleration force.

Alterations in tamping pressure and acceleration force have an impact on

the outcomes of the PT. When tamping force was decreased, the TML

increased when using the standard parameters of 2G acceleration and 25

tamps (Figure 13). Testing results indicate that saturation degree of a loose

sample is less than that of a denser sample provided the moisture content

is the same. The reason why a larger TML is exhibited when compacted by

a smaller tamping force may be due to large liquefaction strength of

unsaturated sample.

Date 8-May-23 of 62

5 10 15 20 25 30 3511.25

11.3

11.35

11.4

11.45

11.5

11.55

11.6

11.65

11.7 PN8 PN7

PN6

PN1

f(x) = − 0.0141142857142857 x + 11.8371428571429R² = 0.92571125104317

Tamping force (kgf)

Aver

age

TML (

%)

Figure 13: The average TML increases with decreasing tamping force at 2G acceleration and 25 tamps per layer ( Sample of Australian Iron Ore Fines: Australia – A)

The TML increased when the acceleration was reduced across a range of

tamping pressures (Figure 14 - Figure 16). Variability in TML values within a

single test operating condition was evident.

Figure 14: Discrete tests in non-consecutive manner using a tamping force of 30 kgf and an acceleration of 1.5 G gives an increased TML compared to a higher acceleration of 2.5 G Sample of Australian Iron Ore Fines: Australia – A

Date 8-May-23 of 62

Figure 15: Discrete tests in non-consecutive manner using a tamping force of 20 kgf and an acceleration of 1.5 G gives an increased TML compared to a higher acceleration of 2.5 G ( Sample of Australian Iron Ore Fines: Australia – A)

Figure 16: Using a tamping force of 10 kgf and an acceleration of 1.5 G gives an increased TML (Sample of Australian Iron Ore Fines: Australia – A)

Date 8-May-23 of 62

3.2.2 Brass bit penetration depth is sensitive to small increments of moisture, leading to inconsistent results.

Large changes in depth of penetration were observed when there were small

moisture increments in the tests (Figure 17). Test 1 and Test 2 were performed

under the exact same testing conditions (i.e., tamping force, number of tamps

and soaking time). The depth of penetration was 30 mm at 11.90% moisture

during Test 1. This moisture content is below the liquefaction criterion that is

specified by the IMSBC Code. Test 2, however, at 11.89% moisture, is

significantly above the liquefaction criteria of 50mm. From this analysis, it is

evident that the brass bit is sensitive to moisture increments that can produce

inconsistent results.

Date 8-May-23 of 62

Figure 17: The brass bit penetration is sensitive to moisture increments Sample of Australian Iron Ore Fines: Australia – A

Date 8-May-23 of 62

3.2.3 There is significant variability in bit penetration depths.

Observations of the test results indicate that: Tamping was more effective at the edges than in the centre of the mould.

Once operating, small particle agglomeration occurred and migrated

towards the centre of the mould.

Measuring the depth of penetration directly from the brass bit, as opposed

to from the rod supporting the brass bit, provided a more accurate reading.

Inadvertent readings measured from the rod included the initial surface

settlement of the sample and hence led to incorrect estimations of TML

values.

The location of the penetration bits was a point of investigation in the tests. Bit

location B was central; Bit location A was offset from center (100mm). The figure

below (Figure 18) shows a statistical summary of the differences in penetration

depths of the two bits for the same test. Over 50% of the tests demonstrated that

the differences in bit penetration were in excess of 16.5mm.

40200-20-40

Median

Mean

22.520.017.515.012.510.0

1st Quartile 4.000Median 16.5003rd Quartile 25.000Maximum 44.000

11.691 19.052

8.352 21.000

13.236 18.523

A-Squared 0.91P-Value 0.019Mean 15.371StDev 15.437Variance 238.295Skewness -0.56119Kurtosis 1.84647N 70Minimum -43.000

Anderson-Darling Normality Test

95% Confidence Interval for Mean

95% Confidence Interval for Median

95% Confidence Interval for StDev95% Confidence I ntervals

Differences in penetration depth of 2 bit locations

Figure 18: Statistical summary of the differences in bit penetration for the PT (Sample from Australian Iron Ore Fines: Australia - B)

Date 8-May-23 of 62

The data was filtered to remove average penetration values less than 50mm. The

figure below (Figure 19) shows the raw output.

Figure 19: The effect of bit position relative to penetration depth - Sample of Australian Iron Ore Fines: Australia - B

There are a number of observations which are evident in Figure 18 & Figure 19:

For 15% of the tests, a flow point is registered for only one of the bits, not

both (and always Bit B).

The median difference in penetration depth is 16.5mm and is largest the

closer the average depth is to 50mm.

The difference in penetration depth shows three zones of behaviour:

o Maximum depth difference when Bit A is less than 50mm – this is

when one bit drops significantly and the other only a little.

o Medium depth difference for Bit A depth 50 – 60mm.

o Small depth difference for Bit A greater than 60mm – this is when

the material flow state has clearly occurred and both bits are

exceeding criteria of 50mm.

Date 8-May-23 of 62

3.3 Proctor-Fagerberg Test (PFT)

The focus of the PFT testing by the TWG was primarily to determine the

applicability for IOF, and to establish its baseline against the other two tests in

the IMSBC Code. The key findings of this work are:

The compaction energy with the Standard Proctor C 350g hammer

produces dry bulk densities greater than those measured at loading for the

products.

The Optimum Moisture Point (OMP) of the Iron Ore Fines (IOF) tested

occurs between 90-95% saturation.

TML precision is deemed satisfactory when a testing method is consistently

applied.

TML increases when the material is screened.

3.3.1 The compaction energy with the Standard Proctor C 350g hammer produces dry bulk densities higher than those measured at loading.

The Standard Proctor C 350g hammer with a 200mm drop height generates a

compaction energy that produces higher dry bulk densities than those

determined at loading. This produces a corresponding impact of lower void ratios

than those generated for the “as shipped” dry bulk density. This is evident for all

ores tested (Figure 20) a sample of Australian Iron Ore Fines ‘Australia – A’;

Figure 21 a sample of Australian Iron Ore Fines ‘Australia – B’; Figure 22 a sample

of Brazilian Iron Ore Fines).

Date 8-May-23 of 62

Figure 20: The average bulk density at loading (red dots/line) demonstrates corresponding void ratios that are higher than those for the Proctor C 350g hammer (Sample of Australian Iron Ore Fines: Australia – A)

Figure 21: The average bulk density at loading (red dots/line) demonstrates

corresponding void ratios that are higher than those for the Proctor C 350g hammer (Sample of Australian Iron Ore Fines: Australia – B)

Date 8-May-23 of 62

Figure 22: The average bulk density at loading (red dot) demonstrates corresponding void ratios that are higher than those for the Proctor C 350g hammer (Sample of Brazilian Iron Ore Fines)

Date 8-May-23 of 62

3.3.2 The OMP of the IOF tested occurs between 90-95% saturation.

The Minimum Void Ratio/Optimum Moisture Point for the IOF tested occurs

between saturations of 90 and 95% compared to the 70 to 75%. Fagerberg had

determined from concentrates of Scandinavian ore (Fagerberg, 1965; Fagerberg

& Stavang, 1971). The figures, Figure 23 - Figure 25 below illustrate this

behaviour for different materials tested.

Figure 23: The Optimum Moisture Points between 95 and 98% (Multiple samples of Australian Iron Ore Fines: Australia – A)

Date 8-May-23 of 62

Figure 24: The Optimum Moisture Points between 90 and 96% (Multiple samples of Australian Iron Ore Fines ‘Australia – B’)

Figure 25: The Optimum Moisture Point at 91% for a sample of Brazilian Iron Ore Fines.

Date 8-May-23 of 62

3.3.3 TML precision is deemed satisfactory when a testing method is consistently applied.

The consistent application of a testing method, when applied to the PFT with both

internal and external laboratories, yields comparable results (Figure 26 Australian

Iron Ore Fines: Australia – A; Figure 27 Brazilian Iron Ore Fines). For the Brazilian

results, the difference between the duplicates for 90% of the dataset is less than

0.15% absolute (Figure 28). This suggests that the simplicity of the test and its

ease of application fosters consistency.

Figure 26: Comparative results of PF tests between an external laboratory and the

laboratory of an Australian Iron Ore Fines producer.

Date 8-May-23 of 62

Figure 27: Comparative results of PF tests between an external laboratory and the laboratory of a Brazilian iron ore fines producer.

Figure 28: PFT TML absolute differences between duplicates for Brazilian Iron Ore Fines.

Date 8-May-23 of 62

3.3.4 The TML increases when material is screened.

In respect of the scope of the PFT procedure, the IMSBC Code states that

“before the PFT is applied to coarser materials with a top size greater than 5 mm,

an extensive investigation for adoption and improvement is required”.

Tests were undertaken to assess the impact of screening on the outcomes of the

TML results for the PFT and are reflected in Figure 29 and Figure 30 below.

Figure 29: The impact of screening Brazilian impacts the TML and is reflective of the fine PSD of the material.

Date 8-May-23 of 62

Figure 30: The TML increases by 0.5% when the top size fraction is reduced from 10 mm to 5 mm Samples of Australian Iron Ore Fines: Australia – A

Figure 31: Screening of samples impacts TML results when using PFT. A lower TML is achieved when including the entire PSD for Samples of Australian Iron Ore Fines: Australia – B

Date 8-May-23 of 62

The observations from these tests are:

TML results as received and screened correlation shows screening does

not affect precision of the test but affects accuracy of test with screened

material giving a higher TML. (Figure 29).

As material is screened and the top size is reduced the TML increases.

Figure 30 and Figure 31.

3.4 Collective Findings

During the research undertaken by the TWG in the evaluation of the current

methods in the IMSBC Code to determine TML, there has been the

establishment of findings that are collective amongst the three tests. The

collective findings of this work are:

For all IOF material tested the PT produced the lowest TML of the three

methods, followed by FTT then PFT.

The PFT demonstrated the highest precision out of the three methods

followed by the PT then FTT.

Mixing technique should be done by non-mechanical bag mixing.

TML results align between the PFT and FTT at lower PSD with screening.

3.4.1 For all IOF material tested the PT produced the lowest TML of the three methods, followed by FTT then PFT.

The TWG completed repeated tests for each of the three methods against materials from Australia and Brazil. Samples were homogenised, split and tested. The results of this work are seen in Figure 32 - Figure 34.

Date 8-May-23 of 62

Figure 32: TML test type base case comparisons showing the difference in results for the three methods and the variation in standard error for Australian Iron Ore Fines ‘Australia – A’.

Figure 33: TML test type base case comparisons showing the difference in results for the three methods for Australian Iron Ore Fines ‘Australia – B’.

Date 8-May-23 of 62

Figure 34: TML test type base case comparisons showing the difference in results for the three methods for Brazilian IOF.


The materials tested from Australia and Brazil identified that the PT

produces the lowest TML result followed by the FT and the PFT (Figure 32 -

Figure 34).

The Brazilian ores have the greatest differences between the PT and FTT

(Figure 34).

The PFT for the materials tested demonstrate similar differences on

average.

3.4.2 The PFT demonstrated the highest precision out of the three methods, followed by the PT then FTT.

As an extension of the baseline testing of the three test methods, a review of the precision of the testing completed was able to be undertaken. The results of this work are seen in Figure 32 and Figure 35.

Date 8-May-23 of 62

Flow TableProctor-Fagerberg

9.00

8.75

8.50

8.25

8.00

7.75

7.50

TML

(%)

Boxplot of Proctor-Fagerberg and Flow Table of Sample A

Figure 35: Precision for the PFT and FTT on Australian Iron Ore Fines ‘Australia – B’.


the PFT produces the lowest variability (Figure 32 & Figure 35).

the FTT exhibits the worst variability (Figure 32 & Figure 35).

3.4.3 Mixing technique should be done by non-mechanical bag mixing.

The mixing technique was explored to determine the impact of different methods. Multiple mixing techniques were investigated for the PFT:

Planetary mixer

Planetary mixer with a modified blade

Cement mixer

Agglomerator

Date 8-May-23 of 62

Hand mixing

Bag mixing

The results were as follows:

The planetary mixer gave lower TML results, both with and without the

modified blade.

The IMSBC code states that a suitable mixer is required that “does not

reduce the particle size or consistency of the test material” (Maritime Safety

Committee 84th session, Section 1.3.2.4).

From the figure below (Figure 36) there is a change observed in the

+4.75mm machine mixed screened sample. There is a visual reduction of

the light coloured material.

Figure 36: Particle degradation as a result of using the planetary mixer

Mixing the material with the agglomerater/cement mixer resulted in a TML

of 11.4%. Despite this, it is clear from Figure 37 that the consistency of the

material has been altered (i.e. change in void ratio, compaction state) while

undertaking any TML test. Therefore, the material cannot be used in

testing. (Maritime Safety Committee 84th session, Section 1.3.2.4).

Date 8-May-23 of 62

Figure 37: Visual observation of particles after using a cement mixer

Mixing the material in a Low Density Polyethylene (HDPE) bag and leaving

it to rest overnight gave the most consistent TML results (Figure 38 & Figure

39).

Figure 38: HDPE bag mixing method

Date 8-May-23 of 62

Figure 39: PFT results from using the bag mixing method with multiple operators.

The PFT plots are shown below for all the tests done to investigate the

effect on TML by varying mixing techniques (Figure 40):

o The planetary mixer and modified attachment (orange, red) gives

a noticeably lower TML. This could be due to a crushing

mechanism.

o The cement mixer and agglomerator significantly change the

consistency of the sample (yellow, green).

o The bag mixing method (purple) does not alter the consistency

and follows the trend of our previous mixing method (blue) closely.

Date 8-May-23 of 62

Figure 40: PFT results from using the various mixing techniques with multiple operators

3.4.4 TML results align between the PFT and FTT at lower PSD with screening.

The TML values for the PFT and FTT align as the PSD is reduced by screening.

Both test methods have the TML result decrease as the full PSD is considered.

The TWG’s research indicates that samples need to be analysed in an “as

received” condition when is comes to PSD and screening, further building on the

key findings in Sections 3.1.1 and 3.3.4. The results of this work are seen in

Figure 41.

Date 8-May-23 of 62

Figure 41: Comparison of the PFT and FTT of duplicate samples and the impact of screening. The TML values for the two methods align as the PSD is reduced by screening.

Date 8-May-23 of 62

Conclusions & Recommendations

The three methods produce a high level of variability when measuring the

behaviour of IOF, but they are used to generate the same output: a TML.

Sample preparation affects the TML result. Sample preparation practices

for each test need to represent the loaded cargo conditions. The sample

preparation includes consideration of moisture addition method (drying,

mixing, equilibration time) and screening.

Particle size distribution and compaction energy drive the difference

between FTT, PT and PFT TML values.

Of the three methods, the PFT is the simplest, least subjective and most

precise (lower variability). The TWG will undertake further research on the

applicability of this test for IOF.

Further research is required for:

o collecting and modelling both real world marine data and material

properties in order to determine the behaviour of IOF material in

various conditions at sea;

o calibrating the PFT with minor adjustments to parameters to reflect

material properties of IOF (i.e., OMP, bulk density, PSD,

mineralogical composition);

o identifying if there is an applicable reference method(s) to

determine the liquefaction potential of IOF to validate the

calibrated PFT;

o identifying and proposing how the research is incorporated into the

IMSBC Code through the Schedule and Appendix 2.

The TWG’s research is focused exclusively on Iron Ore Fines and the findings

are not intended to infer applicability to other cargoes.

The TWG’s research covers the entire range of iron ore mineralogy, providing a comprehensive picture of iron ore behaviour in seaborne transportation. Similarly, the vessels studied range from Handysize to Capesize. .

Date 8-May-23 of 62

Date 8-May-23 of 62

References

References - Flow Table Test (FTT):

Fagerberg, B. & Stavang, A. (1971) “Determination of Critical Moisture Contents in Ore Concentrates Carried in Cargo Vessels”, International Symposium of Transport and Handling of Minerals, 1:174-199; and Guerra, F. “Written Contribution”, of Quebec North Shore and Labrador Railway Company.

Kirby, J.M. (1981) “Liquefaction of Cargoes - A literature Review”, Warren Spring Laboratory, LR388.

Green, P.V. & Kirby, J.M. (1981) “Behaviour of Damp Fine-grained Bulk Mineral Cargoes”, The Institute of Marine Engineers, 94 (19): 2-12.

Tamaki, Dr. (1995) “Determination of transportable moisture limit of bulk cargoes”, URA Institute of Industrial Science, University of Tokyo, website: http://underwater.iis.u-tokyo.ac.jp/research/bulk-e.html, last modified 30 May 1995.

Kvalheim, A., Evenson, E., and Bremseth, A., 1971. Safe Practice for Bulk Cargoes. An Investigation of the Flow Table Method for the Determination of Safe Moisture Limits. Trondheim: Geological Survey of Norway, Nov., 16p.

IMO, 2009. IMSBC Code (and Supplement). 2009 Edition.

IMO, 2009. IMSBC Code (and Supplement). 2011 Edition.

References - Penetration Test (PT)

Ura, Tamaki (1995) “Determination of transportable moisture limit of bulk cargoes”, Institute of Industrial Science, University of Tokyo.

Eckersly, J D., “Coal Cargo Stability” The AusIMM Proceedings, 1997.

Date 8-May-23 of 62

Green, P.V. and Hughes, T.H., (1977). Stability of Bulk Mineral Cargoes, Trans. Inst. Min. Metall., 86, A150-8.

References - Proctor Fagerberg (PF)

Proctor R. R. (1948b). Laboratory Soil Compaction Methods, Penetration Resistance Measurements, and the Indicated Saturated Penetration Resistance. Proceedings of the 2nd International Conference on Soil Mechanics and Foundation Engineering, 5, 242-247 – Apud, Puls, J.M. Compaction Models for Predicting Moisture-density-energy Relationships for Earth Materials. Master of Science Thesis, Iowa State University, Ames, Iowa, 2008, 253 pg.

Proctor, R. R., Engineering News Record – September 7, (1933) Apud, ASTM D698 Standard Test Methods for Laboratory Compaction Characteristics of Soil Using Standard Effort (12 400 ft-lbf/ft3 (600 kN-m/m3))

ASTM D698 Standard Test Methods for Laboratory Compaction Characteristics of Soil Using Standard Effort (12 400 ft-lbf/ft3 (600 kN-m/m3)), 2007. American Society for Testing Materials, (2007).

BS 1377 : Part 4 : 1990, British Standard Methods of test for Soils for civil engineering purposes Part 4. Compaction-related tests. British Standards Institution, (1990).

Fagerberg, B. and Stavang, A., (1971). Determination Of Critical Moisture Contents In Ore Concentrates Carried In Cargo Vessels, In Proceedings of 1st International Symposium on Transport and Handling of Minerals, Vancouver. (Kirshenbaum, N.W. and Argall, G.O., Eds). San Francisco: Miller Freeman Publications, 1971, 174-85.

Fagerberg, B., (1965a). Hazards Of Shipping Granular Ore Concentrates Canadian Mining Journal, 856, July, pp 53-57.

Date 8-May-23 of 62

Fagerberg, B., (1965b). Hazards Of Shipping Granular Ore Concentrates -Parts II. Canadian Mining Journal, 856, Aug, pp 81-86.

Date 8-May-23 of 62

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