School of Civil Engineering
Stabilising the Future of Working Platforms
MSc Geotechnical Engineering & Management
Research Project
David Faux
Student ID: 1305074
September 2015
PRESENTATION FORMAT
• JUSTIFICATION FOR RESEARCH
• AIM OF STUDY & METHODOLOGY
• RESULTS & DISCUSSION

LITERATURE REVIEW

DATA ANALYSIS

CASE STUDY
• CONCLUSIONS
• QUESTIONS
WORKING PLATFORMS - JUSTIFICATION FOR RESEARCH
• HEALTH & SAFETY – CRITICAL IMPORTANCE
• TRADITIONAL WORKING PLATFORM DESIGN – BRE 470

OVER CONSERVATIVE DESIGN

SUSTAINABILITY CONCERNS
• STABILISED SOILS MAY PROVIDE THE ANSWER
• NO DESIGN GUIDANCE FOR WORKING PLATFORMS
• SIGNIFICANT UNDERUSE OF THE METHOD
• ADDITIVES TO IMPROVE MATERIAL PERFORMANCE
• ROADCEM – ADDITIVE BASED ON NANO-TECHNOLOGY
AIM & METHODOLOGY
TO IDENTIFY A VIABLE DESIGN PROCEDURE FOR WORKING PLATFORM DESIGN
USING CEMENT BOUND MATERIAL (CBM).
LITERATURE REVIEW
DATA ANALYSIS
CASE STUDY – LAB TESTING & DESIGN
RESULTS - LITERATURE REVIEW
BRE 470 – WORKING
PLATFORMS FOR
TRACKED PLANT
CBM FOR ROAD
CONSTRUCTION
ROADCEM FOR ROAD
CONSTRUCTION
PRESSURE IMPOSED BY
PILING RIG TRACKS
(UDL - kPa)
IN-SITU SOIL
CHARACTERISATION
(PI, LL, PSD, OMC/DD)
BISAR – STRESS/STRAIN
IMPOSED BY LOADING.
BREAKING STRAIN KEY
DESIGN CRITERIA.
PROPOSED WORKING PLATFORM DESIGN USING STABILISED SOILS
RESULTS - DATA ANALYSIS ROADCEM CBM
12000
RoadCem
Content
10000
8000
0.0 kg/m3
6000
0.9 kg/m3
4000
1.8 kg/m3
2000
2.7 kg/m3
INCREASED
DYNAMIC
ELASTIC
MODULUS
0
50
75
100
125
150
175
200
Cement
225
250
275
300
(kg/m3)
Breaking Strain at 28 days (after Pengpeng, 2011)
400
INCREASED
BREAKING
STRAIN
Breaking Strain (µm)
Dynamic Elastic Modulus (MPa)
Dynamic Elastic Modulus at 28 days (after Pengpeng, 2011)
RoadCem
Content
350
300
250
0.0 kg/m3
200
0.9 kg/m3
150
1.8 kg/m3
100
2.7 kg/m3
50
0
50
75
100
125
150
175
200
Cement (kg/m3)
225
250
275
300
RESULTS - CASE STUDY - BACKGROUND
• SEVERN TRENT – PROPOSED SETTLEMENT TANKS
• CLAYMILLS, BURTON UPON TRENT, STAFFORDSHIRE
• 1381 No. PRECAST CONCRETE DRIVEN PILES
• 6000m2 WORKING PLATFORM REQUIRED
• ONLY ACCESS TO SITE VIA CROSSING RAIL LINE
• SOFT LOW PLASTICITY CLAY AT THE SURFACE
• 650mm WORKING PLATFORM USING BRE470
• SIGNIFICANT LORRY MOVEMENTS TO DELIVER METHOD
• DEEMED UNSATISFACTORY DUE TO COSTS AND IMPACT ON RAIL LINE
RESULTS - CASE STUDY - PRELIMINARY DESIGN
• SOIL STABILISATION USING CEMENT & ROADCEM
• PRELIMINARY DESIGN CRITERIA PROVIDED BY POWERCEM TECHNOLOGIES (2009)
• LOW PLASTICITY CLAY – 1.8/180kg/m3 ROADCEM/CEMENT MIX
• DYNAMIC ELASTIC MODULUS (EMOD) = 4 GPa (DESIGN PARAMETER)
• UNCONFINED COMPRESSIVE STRENGTH (UCS) = 3 MPa (PERFORMANCE CRITERIA)
• BREAKING STRAIN = 200µm (PERFORMANCE CRITERIA)
RESULTS - CASE STUDY - PRELIMINARY DESIGN
• BISAR SOFTWARE – ORIGINALLY DEVELOPED BY SHELL FOR OIL RIG PLATFORMS
• ITERATIVE PROCESS- STRESS/STRAIN/DISPLACEMENT ASSESSMENT
RIG LOADING (kPa)
DYNAMIC ELASTIC
MODULUS (GPa)
DEVELOPMENT OF STRESS/STRAIN
PLATFORM
THICKNESS (mm)
RESULTS - CASE STUDY - PRELIMINARY DESIGN
• STRESS DEVELOPED WITHIN TOP OF LAYER IS WELL BELOW ANTICIPATED UCS
• DISPLACEMENT IS <5mm – NOT SIGNIFICANT FOR WORKING PLATFORMS
• BREAKING STRAIN IS KEY DESIGN CRITERIA – MAINTAIN BELOW 200µm
• CHART BASED ON PROPOSED PILING RIG (RB 5000 HAMMER RIG)
Strain (µm)
Maximum Stain vs EMod per Platform Thickness
EMod
(MPa)
325
300
275
250
225
200
175
150
125
100
3000
4000
5000
6000
7000
8000
150
200
250
Platform Thickness (mm)
• WORKING PLATFORM SHOULD BE 325mm THICK
300
350
RESULTS - CASE STUDY – IN-SITU SOIL TRIALS
• OMC/DD RELATIONSHIP IN ACCORDANCE WITH EN 13286-2
• UCS ON CYLINDRICAL SHAPE MOULDS IN ACCORDANCE WITH EN 13286-41
• EMOD ON CYLINDRICAL SHAPE MOULDS IN ACCORDANCE WITH EN 13286-43
• 3 POINT BENDING TEST ON BEAM SPECIMENS TO DETERMINE BREAKING
STRAIN IN ACCORDANCE WITH EN 1015-11
CASE STUDY – IN-SITU SOIL TRIALS
Dynamic Elastic Modulus (MPa)
Trial Specimens - Dynamic Elastic Modulus
8000
7000
KEY
6000
REQUIRED
EMOD @
5 DAYS
EMod
5000
4000
3000
Min. Req.
EMod
2000
1000
0
0
2
4
6
8
10
12
14
16
18
20
22
24
26
28
30
Days
Trial Specimens - Breaking Strain
Breaking Strain (µm)
REQUIRED
BREAKING
STRAIN @
11 DAYS
275
250
KEY
225
200
Breaking
Strain
175
150
Min. Req.
Breaking
Strain
125
100
75
50
0
2
4
6
8
10
12
14
16
18
Days
20
22
24
26
28
30
RESULTS – CASE STUDY – IN-SITU SOIL TRIALS
• 14 DAY CURING PERIOD SPECIFIED PRIOR TO PILING WORKS
• IN-SITU TRIALS SHOWED HIGHER PERFORMANCE THAN ASSUMED PARAMETERS
• VALUE ENGINEERING – REVIEW STRESS/STRAIN ASSESSMENT
• EMOD @ 14 DAYS = 5500 MPa
Strain (µm)
Maximum Stain vs EMod per Platform Thickness
EMod
(MPa)
325
300
275
250
225
200
175
150
125
100
3000
4000
5000
6000
7000
8000
150
200
250
Platform Thickness (mm)
• REVISED PLATFORM THICKNESS = 250mm
300
350
CONCLUSIONS
• 250mm THICK PLATFORM AND PILING WORKS UNDERTAKEN SUCCESSFULLY
• 400mm REDUCTION FROM TRADITIONAL WORKING PLATFORM DESIGN
• REDUCED THE CONSTRUCTION PROGRAMME BY 3 WEEKS
• SAVED APPROXIMATELY £70,000 ON PROJECT COSTS
• ELIMINATED THE NEED FOR 3600m3 OF SOIL TO BE TAKEN TO LANDFILL
• ELIMINATED THE NEED FOR 3000m3 OF IMPORTED GRANULAR MATERIAL
• ELIMINATED APPROXIMATELY 2000 LORRY MOVEMENTS TO THE SITE
• ELIMINATED THE NEED FOR CONCRETE BINDING OF THE STRUCTURE
CONCLUSIONS
• STABILISED SOILS HAVE THE POTENTIAL TO DELIVER COST SAVINGS
• SIGNIFICANT ENVIRONMENTAL BENEFITS
• ROADCEM CAN IMPROVE THE PERFORMANCE OF CBM:

UNCONFINED COMPRESSIVE STRENGTH

STIFFNESS (EMOD)

BREAKING STRAIN
• PARTICULARLY USEFUL FOR WORKING PLATFORM DESIGN
• FURTHER RESEARCH REQUIRED:

ROADCEM MATERIAL BEHAVIOUR

DIFFERENT SOIL TYPES
• THE DESIGN METHOD SHOWN WITHIN THIS STUDY CAN BE USED FOR FUTURE
PROJECTS
CONCLUSIONS - DESIGN FLOW CHART
WORKING PLATFORMS - QUESTIONS
THANK YOU FOR LISTENING...
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