Sustainable Materials for Civil Engineering & Construction

SUSTAINABLE MATERIALS FOR CIVIL ENGINEERING & CONSTRUCTION

LKAB Minerals Seminar Wednesday 25th September 2019 LKAB AND SUSTAINABILITY

Sustainable Materials for Civil Engineering & Construction Seminar SUSTAINABILITY

3 LKAB and Sustainability 16/09/2019 LKAB’S FOCUS AREAS

Governance and Customer Sustainable Operational Attractive Business Ethics Management Solutions Excellence Employer • Human Rights • Basic Customer • ReeMap • Sustainable • Zero Harm • Code of Conduct Requirements • GGBS Procurement and • Diversity • Modern Slavery (CoC) • Sustainable Supply Chain • Recruitment Act • Quality Underground • Operations and Process • Anti-Corruption Management Mining (SUM) Plant Efficiency • Career • Speak Up! • Certified • Quality & Admin Possibilities Minerals Efficiency • Safety First

These focus areas are based on the owners’ sustainability analysis 2015.

4 LKAB and Sustainability 16/09/2019 REEMAP

5 LKAB and Sustainability 16/09/2019 SUSTAINABLE UNDERGROUND MINING (SUM)

6 LKAB and Sustainability 16/09/2019 HYBRIT

7 LKAB and Sustainability 16/09/2019 LITERATURE

8 Raman Mangabhai

Copyright R Mangabhai Sept 2019 Alternative cements  Calcium aluminate cements  Calcium sulpho-aluminate cement  High belite cement  Limestone Calcined Clay Cements  Alkali-activated cementitious materials  Solidia Technology  Carbon capture process being developed by University of Aberdeen and partners  Carbon capture projects worldwide

Copyright R Mangabhai Sept 2019 Calcium Aluminate Cements (CAC)  Calcium aluminate cement (High alumina cement)  Developed in France in 1908  Introduced in UK in 1920  Sulphate resistance

Chemical resistance Microstructure Industrial effluents and hydration Seawater Sewage Sulfated soil Refractoriness Conversion

Binary/Ternary Systems Industrial process Early strength, Mechanical Fusion Strength Sintering Reactivity with chemicals Expansion

Copyright R Mangabhai Sept 2019 Chemistry and mineralogy of CAC  Raw materials different from PC SiO2 1 Lime 2 OPC Bauxite + limestone or 3 Slags Alumina + Lime 4 CAC CS  A range of C3S2 CAS2 composition wider C2S

than PC C3S Alumina content from 40 to 80 % 1 4  Mineralogy different CaO C3A CA CA6 Al2O3 C12A7 CA2 from PC

Principle Copyrightphase R MangabhaiCA Sept 2019 Manufacture of PC

Mineralogy C3S, C3A, C4AF, CS, CA, C12A7, C2AS, C2S Free lime Ferrite, no free lime Chemistry C : 55-65 A : 35-90 S : 15-25 C : 18-40 A : 3-10 F : 0-15 F : 1-10 TiO2 : 0-4 %

Na2O, K2O Little amount of Na2O, K2O Particle size < 100 μ < 100 μ Blaine 300-400 m2/kg 300-400 m2/kg Colour Grey-white Grey-white f (iron impurities) f (iron impurities)

C : Cao, S: SiO2, Al: Al2O3, F: Fe2O3 CAC hydration

Metastable hydrates easy nucleation CONVERSION time and/or and/or time < 15 ºC 6CAH10 temperature

6CA+60H2O 3C2AH8 + 3AH3 + 27H2O

> 70 ºC 2C3AH6 + 4AH3 + 36H2O

Stable hydrates difficult nucleation

Compressive strength (MPa) Illustrative curve

CAC OPC

CSH diffusion barrier

6-8 hours 28 days

Copyright R Mangabhai Sept 2019 Application of CAC  Refractory  Building chemistry  Sewage  Civil Engineering  Fireplaces  Mining  Cold weather

Copyright R Mangabhai Sept 2019 Alternative clinkers  Calcium sulfo-aluminate cements (CSA)  Reactive belite-rich Portland Cement(RPBC)  Belite calcium sulfo-aluminate (BCSA)

Clinker Manufacturing RM-CO2 Alternative phase enthalpy emissions Clinkers GJ/t kg/t

Alite, (C3S) 1.82 579 /

Belite, (C2S) 1.30 512 RBPC: belite- based Ye’elimite 0.77 216 CSA: CSA-based

(C4A3$) BCSA: belite- [from based

CaSO4]

Gartner and Sui Cement and Concrete Research 2018 Copyright R Mangabhai Sept 2019 Estimated energy saving

Clinker Main Burning % of fuel % of CO2 system composition temperature energy mission % ℃ saved* reduced*

CSA C4A3$ 40-70 1300-1350 15-25 ＞20 C2S 20-40

RBPC C2S 40-65 1350 10-15 ＞10 C3S 20-40

BCSA C2S 40-65 1300 20-30 ＞20 C4A3$ 20-40

Sui ICT Yearbook 2019-20 Copyright R Mangabhai Sept 2019 Properties of HBC (RPBC), MHC and PC

Copyright R Mangabhai Sept 2019 Comparison of mortar strength of HBC (i.e., RBPC), MHC & PC cured at elevated temperature

https://www.lc3.ch/

Copyright R Mangabhai Sept 2019 Quote from Professor Scrivener at ILCCC2019 at UCL  Portland based cement will continue to be dominant  Incredible economy of scale Clinker very low cost  Raw materials abundant nearly everywhere  Easily to manipulate open time  Robust

Copyright R Mangabhai Sept 2019 What is ECC? Engineered Cementitious Composite (ECC), also called Strain Hardening Cement-based Composites (SHCC) or more popularly as bendable concrete, is an easily moulded mortar- based composite reinforced with specially selected short random

fibers, usuallyCopyright polymer R Mangabhai Sept 2019 fib Comparison of various fibre reinforced system

Properties FRC Common HPFRCC ECC Micromechanics based, Design Methodology N.A. Use high Vf minimize Vf for cost and processibility Any type, Vf usually less than Tailored, polymer fibers, Vf Mostly steel, Vf usually > 5%; Fiber 2%; df for steel ~ 500 usually less than 2%; df < 50 df ~ 150 micrometre micrometre micrometre Controlled for matrix Matrix Coarse aggregates Fine aggregates toughness, flaw size; fine sand Chemical and frictional Interface Not controlled Not controlled bonds controlled for bridging properties Mechanical Properties Strain-softening: Strain-hardening: Strain-hardening: Tensile strain 0.1% <1.5% >3% (typical); 8% max Typically several hundred Typically < 100 micrometres Crack width Unlimited micrometres, unlimited during strain-hardening[1] beyond 1.5% strain

Compressive First Crack Ultimate Ultimate Young’s Flexural Density strength (MPa) Strength Tensile Tensile Strain Modulus Strength (kg/m3) (MPa) Strength (MPa) (%) (GPa) (MPa)

20-95 3-7 4-12 1-8 18-34 10-30

Copyright R Mangabhai Sept 2019 ENGINEERED GEOPOLYMER COMPOSITES (EGC) Geopolymer is a sustainable alternative to Portland cement (PC), emitting

at least 80% less CO2 and requiring about 60% less energy as compared to production of PC. Geopolymers can be manufactured by alkaline activation of fly ash and/or slag, being industrial by-products coal power stations and iron manufacture, respectively which contain high volumes of silica and alumina

Copyright R Mangabhai Sept 2019 ECC Formulations  Cement  Supplementary Cementitious Materials  Sand (less than 150 micron)  Water  Fibre (PVA, Polypropylene, Basalt, Recycled Rubber Tyre Fibre)  Superplasticizer  Water/binder ratio is 0.25 to 0.35  Cured at normal temperature

Copyright R Mangabhai Sept 2019 EGC- Formulation  Fly ash (PFA)  Ground granulated blastfurnace slag ( GGBFS)  Metakaolin (MK)  Silica fume (SF)  Sand ( less than 150 micron  Activators (sodium silicate/sodium hydroxide, potassium hydroxide, sodium carbonate)  Superplasticizer  Fibre (PVA, Polypropylene, Basalt, Recycled Rubber Tyre Fibre)  Cured at elevated temperature 40 or 60 °C

Fibre Diameter (µm) Length Tensile Young’s Density Aspect ratio (mm) Strength (MPa) Modulus (kg/m3) (MPa) RECS15-8 40 8 1600 41 1300 200

RECS15-12 40 12 1600 41 1300 300

Copyright R Mangabhai Sept 2019 Mixing ECC - Laboratory  Cement  Sand  Dry mix for 2 min  Add water whilst mixing over a period of time  At the same time add superplasticizer  Mix until it is homogenous

If you are adding fibres then these need to be added slowly to ensure they are mixed.

Copyright R Mangabhai Sept 2019 Mixing for EGC- Laboratory  Ensure Silicate (NaSi) and Sodium hydroxide (NaOH) solutions are prepared 24 hour before  Fly ash or GGBFS or SF or MK in mixing bowl mix for 2 min  Add sand mix for 2 minute  Add the activator solution (NaSi/NaOH) whilst mixing  Add the superplasticizer  Mix until homogeneous  If you are adding fibres then these need to be added slowly until homogenous mix is obtained

Copyright R Mangabhai Sept 2019 Properties of EGC PFA-GGBFS  Workability  Setting time  Compressive strength  Flexural strength  Shrinkage

Copyright R Mangabhai Sept 2019 Percentage increase in 28-day compressive strength, of fibre reinforced geopolymer mortar

Control sample With PVA

500 PVA-PP: 0/0 400

300

200 Load (N)

100

0 0.00 0.10 0.20 0.30 0.40 0.50 0.60 SpecimenMid-span 1 DeflectionSpecimen (mm) 2

Copyright R Mangabhai Sept 2019 EGC PVA 1 and 1.5 % -8MM 900 1000 PVA (8)-PP:1.5/0 PVA (8)-PP: 1.0/0 Specimen 1 800 Specimen 2 Specimen 1 800 Specimen 3 700 Specimen 2 600 600 Specimen 3 500

400 Load (N) 400 Load (N)

300 200 200

100 0 0 0.00 4.00 8.00 12.00 16.00 20.00 0.00 1.00 2.00 3.00 4.00 5.00 6.00 Mid-span deflection (mm) Mid-span deflection (mm)

PVA-PP: 0/0 PVA (8)-PP: 1.0/0 PVA (8) -PP: 1.5/0 0.50 PVA (8) -PP: 2.0/0 PVA (12) -PP: 1.0/0 PVA (8+12) -PP: 1.0/0 PVA (8) -PP : 1.0/0.1 0.45

0.40

0.35

0.30

0.25

0.20

0.15 Drying Shrinkage (%) 0.10

0.05

0.00 0 7 14 21 28 35 42 49 56 Curing Age (day)

Copyright R Mangabhai Sept 2019 Summary of EGC properties Property Compared to Setting time Reduces with increase in fibre content Workability Reduces with increase in fibre content Drying shrinkage Reduces with increase in fibre content Compressive strength Slight improvement Flexural strength Improves by 40- 120 % Fracture toughness Improves by Bridging effect Greater bridging effect and micro cracks are formed

A Sustainable Floor Screed Solution INTRODUCTION

LKAB Minerals

Floor Screed Binders

Specifying Gypsol?

Three Steps to Gypsol

Building Regulations

Underfloor Heating

The Environment

Summary & Questions FLOOR SCREED BINDERS

92 PORTLAND CEMENT BINDER

• For every 1 tonne of Portland cement produced Cement • At least 1.6 tonnes of virgin raw materials are used

o • Processed at 1500 C producing 900kg CO2 per tonne of Cement

• Secondary Waste Streams ALPHA HEMIHYDRATE BINDER

• Harvested from Flue Gas Desulphurisation

• Calcined or Autoclaved at temperatures up to 800 C

• Not Manufactured in the UK

• Not much used in the UK Alpha- Hemi

94 GYPSOL BINDER

• For every 1 tonne of Gypsol Binder Manufactured

• Around 980kg of Landfill is avoided

• No hot processing. Requires no additional heat

• Only 26.26kg of CO2 produced per tonne of GYPSOL • Manufactured in the UK

Gypsol

95 SPECIFYING GYPSOL?

96 THE GYPSOL TRIANGLE

Design & Specification

97 DESIGN & SPECIFICATION

• BS8204:7:2003 • Design Depths with minimum in mind • Full Design Consultancy is available from • 40mm floating commercial the Gypsol Team • 35mm floating domestic • 20mm cover to UFH (Gypsol HTC) • NBS Section M13:2005 • 15mm Bonded (Gypsol TS-15) • NBS Model Specification available from • 15mm Unbonded (Gypsol TS-15 the Gypsol Team • NBS Plus • Design Bays with maximums in mind • RIBA Product Selector • 40m 8:1 unheated • 20m 6:1 heated

98 MANUFACTURE AND INSTALLATION

• Standards • Specialised Equipment • BS EN 13454 - Binder Manufacture • Flow Tests • BSEN 13813 - Screed Manufacture • Placement Pumps • CE Marked • Finishing

• BS8204:7:2003 – Design and Installation • Trained and Certified installers • Lists available via the Gypsol Team

99 POST INSTALLATION AND COVERING

• Post Installation • Coverings • Begins immediately • Should be clean, Sound, Dry and free • Critical Path from contamination • Phased operation • Suitable for all types of floor covering • Guidelines and consultancy available • Care should be taken over adhesive and from Gypsol Team levelling compound selection • Moisture testing advised • Drying Times @ 50mm • Standard Gypsol - 28 days • Gypsol Rapide - 14 days • Dependent on site conditions • Can be force dried • DPM’s can be used

100 BUILDING REGULATIONS

101 PART E – BUILDING REGULATIONS

• Robust Standard Detail • Self compacting • Mostly tied to specific resilient layers • Uniform density @ 40mm = 80kg/m2 • Only 40mm Gypsol Screed Required • Available for use on all substrates • No need to Pre completion test

• Pre completion testing • Designer has free choice of materials • Gypsol offers greater mass due to self compaction

• Large bay sizes means fewer joints • Fewer sound transmission pathways

102 PART L – BUILDING REGULATIONS

No change in floor zone Reduced floor zone • Thinner screed allows for thicker insulation • Retain the same insulation and reduce screed depth • Potential to change to a more “eco-friendly” • Potential 30mm zone reduction insulation for slightly improved U Value • Reduced construction materials and – Some insulations have lower GWP than others ridge height • Reduced costs • Alternatively use thicker depth of same • Reduced embodied energy insulation for significant U value improvement (e.g. higher thermal performance)

103 PART C – BUILDING REGULATIONS In some circumstances the concrete subfloor can be eliminated • Reduced groundworks and muck away • Reduced costs • Simple unreinforced ground-borne slab Gypsol XS Screed

500 gauge Slip Membrane

Insulation

DPM or Radon Barrier

Compacted sand blinded hardcore

104 PART A – BUILDING REGULATIONS

Whilst Gypsol Screeds can significantly enhance the acoustic and thermal properties They are not generally used as a structural topping. Care should be taken to ensure that Part A Compliance is achieved where appropriate.

105 UNDERFLOOR HEATING

106 RESPONSE TIMES – WARM UP

GYPSOL vs S:C Typical Response Curves 50 45 40 35 30 25 20 15

Temperature 10 5 0 1 2 3 4 5 6 7 8 9 10 11 12

GYPSOL S:C Screed

107 DECREMENT

50 GYPSOL vs S:C - Typical Thermal Decrement 45 40 35 30 25 20 Temperature 15 10 5 0 1 2 3 4 GYPSOL5 6 S:C Screed7 8 9 10 11 12

108 COMPARATIVE BENEFIT

GYPSOL SCREED SAND CEMENT SCREED

Thinner Screed Section Thicker Screed Section

High Thermal Conductivity Low Thermal Conductivity

Fast Response Slow Response

High Output Reduced Output

Cost Saving Cost Increase

Energy Saving Inefficient

Lends itself perfectly to Geothermal Systems May require supplementary heat source

109 ENVIRONMENTAL FACTS

110 GENERAL FACTS

Gypsol Screeds are made using Waste Gypsol Screeds make Underfloor heating Material more efficient – saving 0.98 tonnes of landfill per tonne of – COP increased by up to 25% binder – Input Temperature reduced by up to 10oC – No ecological issues with Quarrying – For every 1oC reduction 80kg of carbon saved – For every 1oC £10 saving (based on 60m2) Gypsol Screeds can be laid thinner saving Embodied Energy Gypsol Screeds are 100% recyclable – Reduced Material Use - Feed in to new screed – Increased Insulation depth - Separated to re-harvest raw materials – More Environmentally responsible

111 CARBON FOOTPRINT

Gypsol screed Typical 1:4 cement:sand screed

Binder/tonne 26.26kg Binder/tonne 900kg Screed/m3 22.58kg Screed/m3 281.81kg Screed/m2 (at40mm) 0.90kg Screed/m2 (at75mm) 21.19kg

Typical Potential CO2 Savings (in comparison with 1:4 cement sand screed used floating in accordance with BS EN 8204:1:2003)

House 50m2 saves over 1000kg CO2

Large House 150m2 saves over 3000kg CO2

Primary School 2500m2 saves over 50,000kg CO2

Hospital 12000m2 saves over 240,000kg CO2

If ten million square meters of sand cement screed (Approx 2016 UK consumption) were changed to Gypsol Screed we would save in excess of

200 million kg of CO2 per year

112 SUMMARY

113 • Gypsol Screeds are easy to install accurately to a high level of finish

• Gypsol Screeds are available in formats to suit all applications, depths and drying time requirements

• Gypsol Screeds are a cost effective modern method of construction

• Gypsol Screed significantly reduce the health and safety impact on installers

• Gypsol Screeds are made to national standards offering assured quality

• Gypsol Screeds meet the requirements for part E of the building Regulations

• Gypsol Screed meet the requirements for part L of the building regulations

• Gypsol Screeds significantly reduce the impact on the environment

• Gypsol Screeds improve the efficiency of underfloor heating

• Gypsol Screeds offer massive savings to the Carbon Footprint of construction 114 THANK YOU. THE USE OF GGBS IN SUSTAINABLE CONCRETE

Steve Handscomb Commercial Director, GGBS & Gypsol GGBS – WHAT IS IT?

. Ground Granulated Blastfurnace Slag (GGBS) is a partial cement-replacement which is manufactured from a by-product of the iron and steel industry

. GGBS is mainly used in the production of readymix concrete, pre-cast concrete, cement-based formulations and soil stabilisation

117 GGBS – WHERE DOES IT COME FROM?

. GGBS is manufactured by grinding Granulated Blastfurnace Slag (GBS)

. GBS is Granulated Slag which is a by-product of the iron manufacturing industry

118 GGBS – WHERE DOES IT COME FROM?

Steel Blast Furnace . Temperature Reaches 1850˚c

. Furnace is tapped

. Continuous process

. Slag is lighter than iron, so floats on top of the molten iron

. Slag is separated from the iron in the runner trough

. Slag is approximately +1600˚c

. Molten Slag flows to the granulator

119 GRANULATION OF MOLTEN SLAG

Quenching causes the slag to granulate

120 GGBS – GRANULATED SLAG (GBS)

This is the product that passes from the iron producer to the GGBS manufacturer

121 GGBS – HOW IS IT PROCESSED?

Stage 1 Granulate is dried High pressure rollers then ground to a powder

Stage 2 Ball mill

122 GGBS – HOW IS IT PROCESSED?

. By blending, drying and carefully milling the GBS to a specific fineness through our grinding plant in Scunthorpe, we produce the off white powder of Scunthorpe GGBS

Polycom Roller Press Ball Mill Scunthorpe GGBS Plant

123 GGBS – CEMENT COMPARISON

41% CaO 67%

35% SiO2 20%

12% Al2O3 6% 8% MgO 1%

0.5% Fe2O3 2.5%

GGBS Portland Cement

124 GGBS – CEMENT COMBINATION DESIGNATION

125 KEY STANDARDS GOVERNING THE USE OF GGBS IN CONCRETE

. BS EN 197-1:2011 Cement. Composition, specifications and conformity criteria for common cements

. BS EN 15167-2:2006 Ground granulated blast furnace slag for use in concrete, mortar and grout. Conformity evaluation

. BS EN 206:2013 Concrete. Specification, performance, production and conformity

. BS 8500-1:2015. Concrete. Complementary British Standard to BS EN 206. Method of specifying and guidance for the specifier

. BS 8500 provides notations for “within mixer” combinations containing GGBS: ‒ CIIS: 6-35% of GGBS ‒ CIIIA: 36-65% of GGBS CIIIB: 66-80% of GGBS 126 ‒ GGBS – HOW IT WORKS

127 GGBS – HOW IT WORKS

GGBS is pozzolanic

. When blended with CEM1and water the GGBS reacts with the alkali’s present in the cement and water causing the GGBS reaction

. Some of the hydration products from PC and GGBS combine to form further hydrates which have a pore blocking effect

. This blocking effect reduces the permeability of the concrete once hardened improving its resistance to chemical attacks

128 ADDITION OF GGBS IN A CONCRETE PLANT

CEM1 GGBS GGBS – SUSTAINABILITY AND ENVIRONMENTAL CREDENTIALS

. The only raw material used is a by product from iron manufacture

. Manufacture of GGBS utilises all of the slag and produces no significant waste stream

. The use of GGBS saves quarrying virgin raw material as is necessary in cement manufacture

. Reduces carbon dioxide emissions by 0.88 tonnes for every one tonne of GGBS compared to Portland Cement . Can reduce primary energy use by 3,700 MJ for every one tonne of GGBS compared to Portland Cement

130 COMPARISON OF EMISSIONS - KGCO2 /T

Portland Cement GGBS Process emissions 640 0 Fossil fuel use 100 30 Electricity use 230 25 Total 970 55

131 ENVIRONMENTAL IMPACT OF USING 50%GGBS

. Each year, the UK uses up to two million tonnes of GGBS as a cement addition, which: – Reduces carbon dioxide emissions by approximately two million tonnes – Reduces primary energy use by two thousand million kWhs – Saves three million tonnes of quarrying – Saves a potential landfill of two million tonnes

. Using 50% GGBS reduces the energy demand of concrete by 29%

. Using 50% GGBS reduces CO2 emissions of concrete by 40% GGBS – OTHER BENEFITS

. Pale colour gives an aesthetically pleasing appearance, which is also easier to pigment

. Resistance to sulfate and chloride chemical attack when specified in accordance with BS 8500-1, helps to improve the lifetime of structures

. Reduces the potential damage caused by alkali–silica reaction

. Reduced heat of hydration (reducing the risk of thermal cracking)

. Extended setting time allows for larger pours and reduced risk of cold joints in warmer weather

133 GGBS – THE FUTURE

. The future for GGBS is bright with an increase in demand due to its credentials as a green construction material producing low durable CO2 concrete

. One example of a further development utilising GGBS is as an Alkali-Activated Cementitious Material which requires approx. 95% GGBS and 5% activator creating an ultra low CO2 alternative to traditional cement products.

134 INDUSTRIAL AREAS WHERE GGBS IS USED

135 THANK YOU Creating Sustainable Concrete with Admixtures

Ian Ellis 25th September 2019

137 In 2014 mankind produced 220m3 of concrete…

…causing 60 tons of CO2 emissions…

…per second.

A true challenge !

03.09.2012 Admixtures & Sustainability

The rise in the use of plasticiser & superplasticisers since the mid 1980’s has been substantial At the same time the use of Supplementary Cementitious Materials (SCM’s) has seen similar growth Concrete has been fairly sustainable since then

The classic method of reducing the water content for a given consistence is now almost universally accepted, & admixture technology has moved on at a rapid pace since the introduction of the first generation polycarboxylate ethers (PCE’s) in the late 1980’s EPD’s have been created by EFCA for six concrete admixture categories & are valid until September 2020.

Plasticising & Superplasticising admixtures – GWP = 1.88kg/kg Air Entraining admixtures – GWP = 0.53kg/kg Hardening Accelerating admixtures – GWP = 2.28kg/kg Set Accelerating admixtures – GWP = 1.33kg/kg Retarding admixtures – GWP = 1.31kg/kg Water Resisting admixtures – GWP = 1.87kg/kg

CEMI = 0.86kg/kg CIIIA (50%) = 0.48kg/kg MPA factsheet 18 (Sept 19) Admixtures & Sustainability 3 85.0 CIIIA - 275 & 350kg/m Mixes 2 80.0 14N/mm diff @ 28 Day Strength 7 Day Strength 2N/mm2/10kg = 75.0 70kg cement? 70.0 65.0 Note : 275 & 8.5N/mm2 60.0 diff @ 55.0 2N/mm2/10k 2 29N/mm diff @ g = 40kg 50.0 2 2N/mm /10kg = cement? 45.0 145kg cement & CO 2 2 16N/mm saving of 65.0kg/m3 40.0 diff @ 35.0 2N/mm2/10 30.0 kg = 80kg cement & 25.0 CO2 saving 20.0 of 34.8kg/m3 15.0 10.0 5.0 0.0 275 CIIIA Control Mix - S3 275 CIIIA 569 0.5% / 275 CIIIA 324N 0.6% - S3 350 CIIIA Control Mix - S3 350 CIIIA 569 0.5% / 350 CIIIA 324N 0.6% - S3 350 CIIIA 569 0.7% / 324N 0.2% - S3 324N 0.2% - S3 324N 0.2% - S3 Admixtures & Sustainability

Other opportunities Alkali Activated Concretes Clay contaminated aggregates Belite cements Recycled aggregates Ultra High Performance Concrete Contaminated aggregates CEMIIIB CEMIV-B High air contents – less materials Concrete Mix Optimisation Green Sense Concrete Concrete specifications generally give a framework around which the concrete mix design is generated e.g. Strength grade Durability Minimum cement content Maximum water / cement ratio Exposure class Consistence class Permitted cement types Producers responsibility to design a mix conforming to the most onerous aspect of the specification Concrete Mix Optimisation Overview BS EN 206:2013+A1:2016 is the overriding specification

UK annex is BS 8500-1:2015+A2:2019 & BS 8500-2:2015+A2:2019 Concrete Mix Optimisation Overview BS 8500-1 & 2 define the parameters to be used including the main materials such as cements, additions, aggregates, admixtures & water. In the UK we are fortunate to have cements supplied as separate ingredients rather than as pre-blended materials – this permits flexibility of the selection of the desired blend level Table 1 (2015 version below) was quite “simple” the latest version now spans 3.5 pages

How does this effect Green Sense Concrete?

Green Sense Concrete

“Light Green”

The most basic form of Green Sense Concrete is designed, & produced, using materials and combinations that are permitted by BS 8500-1 & 8500-2. In other words, it’s still compliant to the normal UK practices. Additional quantities of fly-ash, ggbs, limestone fines or silica fume are permitted, but are not part of the cement content, & cannot contribute to any calculation of maximum w/c ratio, &/or minimum cement content. Green Sense Concrete “Light Green” Our aim would be to design a concrete that met, or exceeded, all of the normal properties of the concrete. Preferably this would be either CIIIB (CIIIB +SR) with 80% Ground Granulated Blastfurnace Slag (GGBS) CIVB-V with 55% fly-ash (PFA) Concrete can still be Designated, Designed or Proprietary Careful selection of the admixtures would ensure that the desired consistence level, consistence retention period, setting times & any requirements for early strength were fully satisfied. Green Sense Concrete “Mid Green” As Light Green Sense Concrete but using cements & materials not specifically covered by BS 8500, but that are included in other recognized standards, EN or ASTM for example Green Sense Concrete “Dark Green” Proprietary concrete at its ultimate level. The concrete is not initially designed to comply with any British (or European) Standard based on compositional compliance. The concrete is designed to meet, or exceed, the engineering properties required in the structure in the most sustainable manner possible. Ingredients would be selected to have the lowest impact on the Life Cycle Analysis tool. This requires as early a decision as possible, as a full development & testing regime needs to be implemented, this may require 12 months testing & monitoring before approval. As this concept develops this will be reduced as its likely that a “family” of mixes will start to be produced for a given locality. Green Sense Concrete “Dark Green” Testing can include, but is not limited to.. Compressive strength development profile Flexural strength development profile Bleeding, static segregation resistance Performance at typical annual temperature ranges Modulus of Elasticity Drying Shrinkage Durability testing Chlorides, sulfates, freeze / thaw, carbonation profiling etc Conclusion

Once agreement is made on the style of Green Sense Concrete required, a full series of trial mixes, & evaluations is performed, with the selected concrete producer, to ensure a compliant concrete. For “Light” Green Sense Concrete, this process can be quite short as the main criteria is ensuring strength compliance is satisfied. For “Mid” Green Sense Concrete, the process is similar to that for “Light” unless some additional durability testing is required. For “Dark” Green Sense Concrete, the process is extensive, & can require as much as 12 months development work to fully demonstrate the engineering, & durability properties of the proposed concrete. For Consideration......

Conventional concrete is normally only ever checked by plastic properties such as consistence (workability) & finally compressive strength. All other properties, such as actual durability, are assumed because the concrete & its constituents are assumed to comply with the relevant standards. All the Green Sense Concretes come with a submittal that actually defines & demonstrates the actual performance of the concrete. Thus any risks are essentially removed before concrete is placed. One World Trade Centre Project Overview, GOLD LEED

 135,000 m3 of Green Sense Concrete  Developer: Port Authority of NYC & NJ  Architect: Skidmore Ownings  Structural Engineer: WSP  Contractor: Tishman Construction  Total construction cost: 3.9 bn USD

FastFacts  Height: 541 m

 588,437 litres of production water saved  25,402,200 kWh savings  503,963 kg savings  780,925 kg Solid waste savings Impact Environmental Environmental

154 One World Trade Centre Concrete Characteristics

 83 MPa @ 56 days  MoE 48 Gpa  Heat of hydration to not exceed 70°C  Non air entrained  Cement content < 240kg/m3  Flow 560 – 660mm

Engineering Engineering  Pumping height 40 stories Requirements  No slump loss 3 hours  Class 1 finish

 97 Mpa @ 56 days  SM Heat of Hydration < 70°C  Slag, Flyash & Silica fume used  All other criteria met of exceeded Achieved Green Sense

155 432 Park Avenue Project Requirements

 14000 psi + 2100 psi overdesign (111 MPa) @56d  7.45 million psi (51GPa) MoE @56d  Architectural concrete  White  No discoloring  Self consolidating  Self leveling  Smooth surface finish  Zero blowholes  Max heat of hydration 160 F ~ 71 C  Zero visible cracking  High SCM content  Pumpable – to the top ( around 450 m ) Engineering Requirements Engineering

156 432 Park Avenue Project Achievements

 22500 psi (155 MPa) @56d  7.67 million psi (53GPa) MoE @56d  Architectural concrete  White  No discoloration  Self compacting  Self leveling  Smooth surface finish  Zero bugholes  Max heat of hydration 147 F ~ 64 C  Zero visible cracking  High SCM content - 71%  Pumpable Green Sense Concrete Achieved Green Concrete Sense

157

The Shard London

 Key requirements needed for the concrete on this project were quality of finish and speed of curing to support fast- track working without sacrificing other performance properties.

 A massive continuous concrete pour was planned as part of the construction of the three-floor basement box, which had a depth of 13.3 metres and required a total volume of concrete of 15,000m³.

 The structure’s core was slip-formed in reinforced The Challenge The concrete and progressed at an impressive rate of three metres a day whilst the basement levels were built top down simultaneously.

 The record-breaking concrete pour for the basement’s construction, the largest UK continuous concrete pour to date, started at 5 pm on Friday 16th April 2010 and went on until 4 am on Sunday 18th April.

 The programmed time had been 36 hours for 5,000 m³ of concrete, using four concrete pumps.

Project Facts  The actual placement time for 5480 m³ was 35 hours, beating the schedule both on time and volume.

159 Concrete: Friend of Foe?

Richard Day: Head of Technical Services Concrete: Friend or Foe?

The Concrete Society • Membership organisation • Provider of information; . Advisory service . Technical publications . CONCRETE and Concrete Engineering International . Library service . Web-site Concrete: Friend or Foe?

• Incorporated as a not-for-profit organisation, limited by guarantee, on 28 July 1966 • Independent Membership Organisation . 450 company members . 250 individual members . 1600 nominees • From across suppliers, professions & academia Concrete: Friend or Foe?

Magazines Concrete (Monthly) Concrete Engineering International (biannually) Concrete: Friend or Foe?

Technical Reports

TR 73 Cathodic protection of steel in concrete and Specification

TR 74 Cementitious additions; ggbs, fly ash, silica fume and limestone Concrete: Friend or Foe?

Visual Concrete

. Finishes . Planning and assessment . Control of blemishes . Weathering, stains and efflorescence Concrete: Friend or Foe?

1. The provision of holes in reinforced concrete beams 2. Suspended concrete floors: Maximum size of pour allowable and location of construction joints 3. Straightening and rebending reinforcement on site 4. Congested reinforcement: effects on placing and compacting concrete 5. Holding down bolt design: suggested procedures 6. Reinforcement ripple 7. Galvanised steel reinforcement 8. Crazing: power trowelled concrete floor slabs 9. Autogenous healing: the self sealing of fine cracks 10. Design of suspended slabs on ground 11. Abrasion resistance of floors containing lightweight coarse aggregate 12. Power -trowelled concrete floor and lignite 13. Cracking in composite/corrugated metal decking floor slabs 14. Concrete surfaces for painting 15. Thin floor coverings on cement: sand screeds 16. Assessing as struck in-situ concrete surface finishes 17. Achieving good quality as struck in-situ concrete surface finishes 18. Delamination of concrete surfaces 19. Historic reinforcement and steel fabric 20. Curing concrete 21. Dark discoloration on smooth formed concrete surfaces (mottling) 22. Moisture in concrete floors 23. Large area pours for suspended slabs 24. Rendering defects 25. Large volume concrete pours Currently 65 no. Concrete: Friend or Foe?

Fingertips information Concrete: Friend or Foe?

Fingertips information nugget Concrete: Friend or Foe?

We don’t do sustainability! . Relatively quiet on the subject . No publications directly dealing with this topic . Why?

Mineral Products Association MPA . In particular The Concrete Centre . “This is Concrete” campaign (sustainableconcrete.org.uk) Concrete: Friend or Foe?

The Concrete Society has achieved the BS 8500 durability milestone of ……..

“intended working life of at least 50 years” Sustainability Concrete: Friend or Foe?

Industrial and Roads and farm bridges 15% 10% Schools and Utilities hospitals 12% 9%

Offices, shops Private housing etc 26% Social housing 23% 5%

Where is concrete used? Concrete: Friend or Foe?

CO2-eq emissions by source (1997 data). Production of concrete accounts for some 2.5% of total UK emissions of which cement accounts of 1.1%

Environmental datasheet published in Concrete, Sept 2001 Concrete: Friend or Foe?

• A Buildings energy consumed over 60 years. • About 10% attributed to construction Concrete: Friend or Foe?

So why Friend of Foe?

• The guardian earlier this year Celebrated the aesthetic and social achievements of concrete But also Investigated concrete’s innumerable harms Concrete: Friend or Foe?

And exclaimed Concrete is the…

“most destructive material on Earth!” Concrete: Friend or Foe?

Guardian said… We are only now waking up to concrete’s dangers . up to 8% of global CO2-eq, . clogged landfills, . urban flooding, . overheated cities, . toxic dust, . freshwater consumption . destroyed beaches and lakes, . “sand mafias” Concrete: Friend or Foe?

….. and arguably a direct impact on the current mass extinction

….. as urban environments encroach on the natural world and entomb biodiversity. Concrete:Concrete: Friend or Friend Foe? or Foe? We’re all

Private Frazer, Dad’s Army doomed, Doomed! Concrete: Friend or Foe?

• Guardian has a valid point . as well as newspapers to sell

• Environmentally CO2-eq emission from cement and concrete production is…. ‘the work of the devil’ Concrete: Friend or Foe?

Perhaps not as visible as William Blake’s ‘dark satanic mills’ but CO2-eq is an invisible threat to the environment. Concrete: Friend or Foe?

The importance of Design at all levels • Design guru Dieter Rams - 1932 • Design makes an important contribution to the preservation of the environment. • It conserves resources and minimises physical and visual pollution throughout the lifecycle of the product.

• 10 rules for good design Concrete: Friend or Foe?

1. Is innovative 2. Makes a product useful 3. Is aesthetic 4. Makes a product understandable 5. Is unobtrusive 6. Is honest 7. Is long-lasting 8. Is thorough down to the last detail 9. Is environmentally friendly 10. Involves as little design as possible Concrete: Friend or Foe?

Rule 10 - can be summarised as “Less is better” Concrete: Friend or Foe?

“Less is better”

Rams’ applied the rules to a product but these (especially Rule 10) could also apply to;

• Constituents (cement, aggregate etc) • Building elements (floors, columns etc) • Final Structure Concrete: Friend or Foe?

Definition of sustainability (and there are many to choose from) encompasses ‘whole life’

• ‘Whole life’ traditionally based on building ownership/cost • Now encompasses broader issues i.e. embodied CO2 • Even though a constituent or element is perceived as ‘negative’, the well-designed structure over its lifetime is a ‘positive environmental contribution’ Concrete: Friend or Foe?

Concrete and the environment • Ingredient cement suggests Bad • Conglomerate Concrete as product less Bad • Concrete structure, has little impact difference to other building materials • Whole life of concrete structure – very sustainable (it’s the lifetime running that’s emits the significant CO2-eq contribution) • Is Concrete humanity’s foe? Concrete: Friend or Foe?

In Perspective • Concrete is strong, resilient and durable • Short term construction has little impact on whole life impact • Design and construction for operational efficiency is more critical than the concrete per se • We can make changes at every stage – every little helps: “Less is better” . beware detrimental effects to the construction process by being over zealous with cement replacement Concrete: Friend or Foe?

Lean design for sustainability • Reduce material use o Allow time for slower strength development o Alternative cements with less CO2-eq • Optimise in-service performance • Design for flexibility and future re-purposing • Design for longevity Concrete: Friend or Foe?

Utilise thermal mass • Avoid supplementary surfaces . Suspended ceilings, plaster board, carpet, tiles • Use polished concrete wearing surfaces • Reduce peak cooling loads, smaller air con • Passive approach to comfort Concrete: Friend or Foe?

Foundation solutions • Not much can be done • Optimise materials • Optimise element sizes • Incorporate ground source heat pumps Concrete: Friend or Foe?

White Collar factory, London (Allford Hall Monaghan Morris) Concrete: Friend or Foe?

Change construction practice • Allow time for slower strength development . Alternative cements with less CO2-eq

Existing frame reuse • Don’t just demolish Concrete: Friend or Foe?

George Green Library refurbishment & extension. University of Nottingham (ARUP) Concrete: Friend or Foe?

Definition Sustainable products are those products that provide environmental, social and economic benefits while protecting public health and environment over their whole life cycle, from the extraction of raw materials until the final disposal.

en.m.wikipedia.org/wiki/Sustainable_products

Does this not describe concrete? Concrete:Concrete: Friend or Friend Foe? or Foe?

Hurst Castle, Lymington Hampshire – Concrete c1880 Concrete: Friend or Foe?

Concrete offers massive benefits from cradle to grave

SO IS CONCRETE…………. • The work of the devil? • A Saint OR Sinner? • Friend or Foe? MAGNETITE CONCRETE AS A SUSTAINABLE CIVIL ENGINEERING SOLUTION

Content accredited by the Institute of Concrete Technology TOPICS COVERED TODAY

• The dense mineral from Sweden • Swedish Magnetite aggregate properties • Dense concrete • Dense concrete case studies • Carbon Footprint data BASED IN SWEDEN – GLOBAL OUTLOOK Production Kiruna/Malmberget HQ, sales office, Port Port of Narvik /Svappavaara Luleå Founded Norway Production Mica 1890 Production, sales offices Finland England1 Produktion & sales office Stockholm Sales office Net sales, 2018, SEK Production, stock2 & Tianjin, China sales office Moerdijk 26 billion Trading office Huntite mine Shanghai, China Turkey Sales office 4 sales offices Chicago 3 Europe Region-HQ Asia, sales 100% office, Hong Kong owned by the Swedish state

4200 Employees in 12 countries

1. Flixborough, Stockton, Lund, Derby, Gurney slade, Wicken, Runcorn, Scunthorpe 2. Mainly magnetite 3. Germany, Spain, Slovakia,, Greece LKAB MINERALS INDUSTRIAL MINERALS

OWN 400 11 minerals; Magnetite and employees countries Huntite from own deposits PORTFOLIO 212 Recycle mineral products GGBS, 100% MEURO turnover in 30+ 45+ external sales minerals Refractory and Limestone, process industrial uses 2018 and trade many more. 201 LKAB Special Products Division MINERAL PROPERTIES

202 SWEDISH MAGNETITE PROPERTIES

• Black, hard mineral with a rough surface texture, producing an aggregate shape similar to limestone

• Chemical Composition – Iron Oxide – Fe3O4 • Typically 65-70% Fe and has ferrimagnetic properties • Specific Gravity / Particle density 4.7 – 5.2 t/m3 • Chemically inert (pH neutral), non-hazardous and durable • Loose bulk density 3.0 ± 0.2 t/m3 depending on grade • Mohs hardness 5.5 • Thermal expansion (~0.0015/100oC) • Low water absorption < 0.3% GRADES FOR HIGH DENSITY CONCRETE & BALLAST

Standard available grades: • Dense aggregates are specialised minerals conforming • m2-20m to normal aggregate sizes and standards such as BS EN 12620 • 0-8mm • 0-2mm • Blending by LKAB Minerals or at batching plant • 0.5mm • Milled grades also available to 0.09mm (90 μm) DENSE CONCRETE

205 DENSE CONCRETE – WHY IT REDUCES CARBON FOOTPRINT

More weight for the same volume • More weight per cubic metre compared to normal concrete • Increased weight for a given volume

Normal concrete – 100%

Same weight with less volume Dense • Up to 40% less volume for a given weight, less concrete – 60% concrete required, which means less cement in overall volume therefore major reduction in CO2 emissions. Further reductions when using GGBS. DENSE CONCRETE - PROPERTIES

Submerged properties Thermal properties • Buoyancy • High specific heat capacity • Lower centre of gravity for offshore • Significantly reduces risk of thermal cracking structures • Negates hydrostatic pressure

Concrete Curing Exotherms

Normal Concrete

MagnaDense Concrete Degrees Centigrade Degrees 60% 75% 20

0 0 1 2 3 4 5 6 7 8 9 10 11 12 Day DENSE CONCRETE – CARBON FOOTPRINT

208 DENSE CONCRETE - CARBON FOOTPRINT

(kg/tonne)

CO2 emissions directly from cement production 679

CO2 emissions from crushed rock 3.8

CO2 emissions from sand and gravel - land-won 3.5

CO2 emissions from MagnaDense 20s production 6.71

CO2 emissions from MagnaDense 8s production 5.86

CO2 emissions from production of steel 1900

** CO2 reduction comes from decrease in cement required per tonne of concrete

209 PORT TO PORT – MAGNADENSE 20S

Based on 4000-6000 MT shipment

• From Kiruna mine, Sweden • to Narvik Port, Norway – mining, sorting, refining, transport to port

– 6.71 kg CO2/MT

• Narvik Port, Norway • To Grimsby Port, United Kingdom – Distance of 2,058 nautical miles

– Emission factor vessel ranging between 6.07 – 19.20 kg CO2/tonne distance

– Emission** 17.00 kg CO2/MT

Total emission 23.71 kg CO2 / MTon

** taken from average of last 4 ships PORT TO PORT – MAGNADENSE 8S

Based on 4000-6000 MT shipment

• From Kiruna mine, Sweden • to Narvik Port, Norway – inc mining, sorting, refining, transport to port

– 5.86 kg CO2/MT

• Narvik Port, Norway • to Grimsby Port, UK. – Distance of 2,058 nautical miles

– Emission factor vessel ranging between 6.07 – 19.20 kg CO2/Tonne distance

– Emission** 17.00 kg CO2/MT

Total emission 22.86 kg CO2/MT

** average emission from last 4 ships PORT TO PORT – MAGNADENSE 2

Based on 4000-6000 MT shipment

• From Malmberget mine, Sweden • to Narvik Port, Norway – inc mining, sorting, refining, transport to port –

– 2.78 kg CO2/MT

• Narvik Port, Norway • to Grimsby Port, UK. – Distance of 2,058 nautical miles

– Emission factor vessel ranging between 6.07 – 19.20 kg CO2/Tonne distance

– Emission** 17.00 kg CO2/MT

Total emission 19.78 kg Co2 / MT

** Average emission from last 4 shipments HEAVY CONCRETE & BALLAST - APPLICATIONS

213 CIVIL ENGINEERING & CONSTRUCTION

• Radiation Shielding – Walls/roofs of oncology units – Decommissioning containers – Nuclear waste bunkers and encapsulation

• Civil Engineering & Construction – Bridges • Anchor blocks • Counterweights – Tunnels • Heavy concrete • Sound dampening on floating track slabs – Foundations • Poor ground conditions • Hydrostatic Pressure OIL & GAS & RENEWABLES

• Floating platforms – Spars - oil & gas – Wind turbines

• Large gravity based structures – Oil and gas platforms – Wind turbine foundations

• Pipe Coating – Heavy concrete coated pipes – Grout (for repairs) OFFSHORE

• Tidal energy • Wave energy • Erosion/Scour Protection – Antifer – Tetrapod – Accropode

• Anti-buoyancy elements – Profiles – Mattresses OTHER APPLICATIONS

• Water treatment • Heavy media separation • Counterweights • Night Storage Heaters • Ferroalloy production • Catalysts • Brake pads and linings • Paint • Sponge Iron HEAVY CONCRETE & BALLAST – CASE STUDIES

218 HEALTH MONKLANDS HOSPITAL, GLASGOW

219 MONKLANDS HOSPITAL

Problem/Solution • Limitations on space due to location • Thinner sections were required to maximise floor Project details space. •Concrete density of 3.9 t/m³ •Concrete supplied 2800m3 What it meant for the project •Concrete strength 50N/mm2 40% reduction on wall thickness •3 Radiation bunkers for shielding Reduced cement, reduced steel formwork, •800t MagnaDense supplied Reduced man hours for pouring

Hugh Cowan, Aggregate Industries “LKAB’s MagnaDense produced an excellent surface finish.” WIRRAL BRIDGE

Problem/solution • Hydraulic bridge with high density counterweight • Existing infrastructure limited space • Heavy concrete acted as counterweight to lift bridge. • Energy and space saving solution

Project details • 3200 kg/m3 density • 350mt MagnaDense

What it meant to the project regarding carbon footprint • Major reduction in steel used for the whole structure • Reduction in Concrete used in the ballast box (30% less) • Reduction in energy used to o[pen and shut bridge. TUNNELS CROSSRAIL & ST PAULI ELBE CROSSRAIL C610 – BARBICAN & SOHO

Problem/solution Project details: • Floating track slab (FTS) required for sound & vibration • Concrete density 3.6 t/m3 dampening; • Pumped 980 metres into tunnel • Space restrictions due to surrounding infrastructure & • 12.3 m3 (44 tonnes) of concrete in pipeline at farthest gauge of train; point • Total concrete in project 4000m3 Parties involved What it meant for the project • Arup/Atkins JV design of over 20 years; • Allowed trains to pass in bored tunnel • Supplied by London Concrete to ATC JV; • No requirement for extra boring • Pumping Company: Camfaud Concrete Pumps. • Reduced level of concrete slab required.

Andrew Turner, Camfaud Pumps Ltd “Having pumped almost 1000m3 of MagnaDense concrete I would say it is easier to pump than standard concrete”

223 HYDROSTATIC PRESSURE KILBURN KILBURN

Problem/solution • Concrete used to surround pipes and sewers for Project details new apartment blocks • Concrete density 3.8 t/m3 • Hydrostatic pressure • Total concrete in project 1800mt • Total concrete coverage 300m3 Parties involved • Site: Maida Vale, Kilburn What it meant for the project • Main Contractor: GCL (Ground Construction Ltd) • No requirements for dig out and muck away for • Consulting Engineers: Arcadia new sewers. • Concrete Producer: London Concrete • 40% reduction in slab thickness to combat hydrostatic pressure OIL & GAS & RENEWABLES DRAUGEN RECLAIM & RECYCLE

The Draugen Floating Loading Platform (FLP) when it was operational, in the background some 3 km away the Draugen Oil and Gas Platform is visible.

226 DRAUGEN RECLAIM & RECYCLE

Problem/solution Project details: • End of life decommissioning • 150km offshore Norwegian Coast • Start date 2014 Finished 2015 Parties involved • 60 M Norwegian Krone Project • Shell Norway • 99% material recycled • Kvaerner Stord • No treatment required unlike water and concrete ballast • 4000mt MagnaDense 8s resold to LKAB Minerals LITERATURE

228 SUMMARY BENEFITS OF HEAVY CONCRETE

A solution for civil engineering challenges.

Magnetite concrete • Density up to 4 t/m3 • 60% heavier than a standard concrete (3.9t/m3) • A wall thickness of 1.5m in 2.3 t/m3 concrete becomes 0.9m of 3.9 t/m3 concrete – a reduction of 40% • Reduces building footprint, or provides more space in existing footprint • Lower tendency for stress-cracking due to reduced thickness and heat-sink properties

Benefits • Reduction of cement used in concrete due to less concrete being required. • Less dig out and much away – less truck movements • Less formwork – Less steel due to smaller space • Less man hours

230 High Density Concrete

Shaft Infill Design Case Study INSERT IMAGE OF CHOICE IN THIS BOX 25 September 2019 Shaft Infill Project, London

• Heavy Weight Concrete (HWC) plug to infill inlet shafts • HWC plug resists hydrostatic uplift pressures Shaft Infill Case Study Shaft Infill Case Study

Preliminary Assessment

A preliminary assessment was undertaken to provide options for plugging the shaft using the safest and most cost-effective method. Various options were identified and considered and one option was agreed and adopted for the plugging of the shafts.

Detailed Design

The agreed option adopted a combination of stone fill, HWC and normal concrete with hydrophilic water bars to prevent future leakage along the top section of the plug. Shaft Infill Case Study Shaft Infill Case Study

Construction

• HWC placed in layers to prevent potential sliding of the stone layer due to the weight of the HWC • On completion of the final layer of HWC and once the concrete has set, the water within the shaft is completely pumped out • Waterbar ring is fixed to the shaft perimeter • Normal weight concrete then placed above the HWC Benefits of Heavy Weight Concrete

•HWC plug occupies less space than normal weight concrete •HWC use minimises the need for people working inside the shafts drilling dowels etc. Otherwise the plug would require a large volume of normal weight concrete, potentially flooding the interlinking galleries. •Volume of concrete to be produced, delivered and placed considerably reduced by using HWC High Density Concrete

LINAC Bunker Design Case Study INSERT IMAGE OF CHOICE IN THIS BOX 25 September 2019 LINAC Bunker Case Study

• LINAC: Linear particle accelerator for radiation cancer therapy • Bunker designed to attenuate the radiation from the LINAC with maze layout and thick concrete walls LINAC Bunker Case Study

• Two scheme designs prepared for cost comparison study • For a typical LINAC bunker, the shielding requirements were calculated by a Radiation Protection Adviser (RPA) for:

o Normal density concrete 3 o High density concrete (3900kg/m ) LINAC Bunker Case Study

Normal density concrete High density concrete LINAC Bunker Case Study

Normal density concrete High density concrete Cost Comparison Cost Comparison LINAC Bunker Case Study

• Total costs for the two options are comparable • Significant benefits of the High Density concrete option are:

o 20% less floor area o 16% less height = 0.9m INSERT IMAGE OF CHOICE IN THIS BOX Thank You Jack Sindhu Technical Manager Capital Concrete.

Specifying, designing , producing and supplying heavyweight concrete from the prospective of a Readymix Concrete Producer. Specification.

• Correctly Specified – Be Realistic

• Strength

• Workability, slump , flow

• Density if applicable

• Placement method

• Open life / Slump retention / Retardation

• Early engagement Mix Design.

• Selection of materials

• Material physical and chemical properties

• Methodology , Proportioning

• Interaction with admixtures

• Trial mixes prior to supply for checking robustness and reproducibility of mix Production.

Plant types: Dry or Wet batch , types of mixer

Mixing cycles and procedures

Batch procedures

Plant modifications etc Supply.

Requirements and frequency and spacing between deliveries

Logistics , enough materials for supply and haulage.

Testing regime , compliance testing , on site checking , types of vehicles required e.g. mixers or tipper or even collect. THANK YOU FOR YOUR SUPPORT