Presentation is loading. Please wait.

Presentation is loading. Please wait.

2E8 Materials (Civil Engineering Component) Civil Engineering Materials Department of Civil, Structural and Environmental Engineering Trinity College Dublin.

Similar presentations


Presentation on theme: "2E8 Materials (Civil Engineering Component) Civil Engineering Materials Department of Civil, Structural and Environmental Engineering Trinity College Dublin."— Presentation transcript:

1 2E8 Materials (Civil Engineering Component) Civil Engineering Materials Department of Civil, Structural and Environmental Engineering Trinity College Dublin Dr. Roger P. West (TCD) And Mr. Peter Flynn (Arup)

2 2E8 Materials (Civil Engineering Component) Schedule Lectures: –Weeks 1-3(Wed 3-5): Timber, aluminium, glass and pre- cast –Weeks 4-9(Mon 10-11, Fri 3-4): Concrete, reinforced concrete and pre-stressed concrete Tutorials: –Alternate weeks, weeks 4-9, Thursday 5-6pm, commencing Groups 1-20 in week 4 of term, in Joly Theatre Concrete Laboratory: –Each laboratory group on either Monday or Thursday, for one week only, as per timetable

3 2E8 Materials (Civil Engineering Component) Section A:Concrete A1Basic Materials: A2Fresh Concrete Properties: A3Hardened Concrete Properties: A4Concrete Mix Design: A5Reinforced Concrete: A6Pre-stressed Concrete:

4 2E8 Materials (Civil Engineering Component) Concrete is a construction material composed of crushed rock or gravel and sand bound together with a hardened paste of cement and water. Concrete is the most widely used construction material in the world What is Concrete?

5 2E8 Materials (Civil Engineering Component) Concrete History

6 2E8 Materials (Civil Engineering Component) Aquaducts Concrete History

7 2E8 Materials (Civil Engineering Component) Colleseum Concrete History

8 2E8 Materials (Civil Engineering Component) Pantheon Concrete History

9 2E8 Materials (Civil Engineering Component) Eddystone Lighthouse – John Smeaton (1756) Concrete History

10 2E8 Materials (Civil Engineering Component) Joseph Aspdin Patent (1824) Concrete History

11 2E8 Materials (Civil Engineering Component) Reinforced Concrete Flower Pot (Joseph Monier 1867) Concrete History

12 2E8 Materials (Civil Engineering Component) Weavers Mill Swansea (1898) Concrete History

13 2E8 Materials (Civil Engineering Component) Freysinnet Concrete History

14 2E8 Materials (Civil Engineering Component) Hoover Dam Concrete History

15 2E8 Materials (Civil Engineering Component) Astrodome Concrete History

16 2E8 Materials (Civil Engineering Component) Toronto Tower Concrete History

17 2E8 Materials (Civil Engineering Component) Section A.1Basic Materials 1.Cement 2.Water 3.Aggregates 4.Admixtures

18 2E8 Materials (Civil Engineering Component) Section A.1Basic Materials 1.Cement Ordinary Portland Cement(OPC) Sulphate Resistant Portland Cement(SRPC) White Portland Cement(WPC) Rapid Hardening Portland Cement(RHPC) Masonry Portland Cement Low Heat Portland Cement Hydrophobic Portland Cement Oil-well Portland Cement Specialised Portland Cements:

19 2E8 Materials (Civil Engineering Component) Alternative Cement Replacement Materials Blastfurnace Slag Cement(GGBS) Pulverised-fuel Ash Cement(PFA) Metakaolin Rice Husk Ash Silica Fume Cements in Europe are classed as CEM1 (OPC or RHPC), CEM2-4 (OPC with limestone, PFA or GGBS) in varying proportions pre-blended

20 2E8 Materials (Civil Engineering Component) Section A.1Basic Materials Chemistry of OPC 1.Cement

21 2E8 Materials (Civil Engineering Component) Section A.1Basic Materials 1.Cement Manufacture

22 2E8 Materials (Civil Engineering Component) Section A.1Basic Materials 1.Cement Manufacture

23 2E8 Materials (Civil Engineering Component) Section A.1Basic Materials Sulphate Resistant Portland Cement Low triacalcium aluminate content (C3A) Achieved by adding Iron oxide to decrease aluminate proportions Resistant to sulphates but not resistant to strong acids Reduced early heat 1.Cement

24 2E8 Materials (Civil Engineering Component) Section A.1Basic Materials Pulverised-fuel ash cements (latent hydraulic binder) From burning pulverised coal in power station furnaces Reacts with calcium hydroxide (lime) to from cementitious material Resistant to sulphates but not resistant to strong acids Reduced early heat of hydration 1.Cement Reduced early age strength

25 2E8 Materials (Civil Engineering Component) Section A.1Basic Materials Blastfurnace Slag Cements (latent hydraulic binder) By-product of iron smelting, quenched slag forms granuels Generally blended with OPC up to 35% Reduced early age strength Reduced early heat of hydration 1.Cement

26 2E8 Materials (Civil Engineering Component) Section A.1Basic Materials

27 2E8 Materials (Civil Engineering Component) Section A.1Basic Materials

28 2E8 Materials (Civil Engineering Component) Section A.1Basic Materials

29 2E8 Materials (Civil Engineering Component) Section A.1Basic Materials Delivery & Storage Usually packaged in 25kg bags or transported in bulk tankers Retail price €5 1.Cement “Warehouse set”

30 2E8 Materials (Civil Engineering Component) Section A.1Basic Materials Should be free from impurities Sea water must not be used for reinforced concrete 2.Water Unsuitable if it contains- sugars - sulphates - chlorides

31 2E8 Materials (Civil Engineering Component) Section A.1Basic Materials Setting and hardening results from a chemical reaction between the cement and the water, not from a drying process. Hydration The paste is usually workable up to two hours before it begins to harden The reaction is exothermic and is irreversible. The heat produced is known as the “Heat of Hydration” C 3 A and C 3 S are the compounds primarily responsible. Strength gain is initially rapid becoming progressively less rapid Strength gain continues indefinitely provided moisture is present. “Curing”

32 2E8 Materials (Civil Engineering Component) Section A.2Fresh Concrete Properties 2.Cement hydration Cement + H 2 O = Calcium Silicate Hydrate (C-S-H) +Ca (OH) 2 +H 2 O

33 2E8 Materials (Civil Engineering Component) Section A.2Fresh Concrete Properties 2.Cement hydration and heat generation

34 2E8 Materials (Civil Engineering Component) Section A.1Basic Materials 2.Cement paste strength gain

35 2E8 Materials (Civil Engineering Component) Section A.1Basic Materials Gravels, crushed rock and sands that are mixed with cement and water to produce concrete. Coarse aggregates are those that do not pass through a 5mm sieve. Fine aggregates are those that pass through a 5mm sieve. Generally make from 50% to 80% of the concrete mix. Used to reduce cost and modify and imporve properties like strength and drying shrinkage. 3.Aggregates

36 2E8 Materials (Civil Engineering Component) Section A.1Basic Materials Quality Requirements Durability-Hard -Adequate Strength -No deletrious material Cleanliness-free from chemical impurities -free from organic material -free from dust -excessive washing is not the answer -avoid silica acid aggregates. 3.Aggregates

37 2E8 Materials (Civil Engineering Component) Section A.1Basic Materials Aggregate Types Normal density-Most gravels and crushed rock -Divided into coarse and fine Lightweight -Weak porous solids -Good thermal properties 3.Aggregates High Density -radioactive screening

38 2E8 Materials (Civil Engineering Component) Section A.1Basic Materials Sieve Analysis 3.Aggregates

39 2E8 Materials (Civil Engineering Component) Section A.1Basic Materials 4.Admixtures Additives to the concrete mix to improve certain properties Must be used with care as excessive amounts can have adverse effects on the concrete

40 2E8 Materials (Civil Engineering Component) Section A.1Basic Materials 4.Admixtures Accelerators Increases the rate of strength gain at an early age Most common is calcium chloride (CaCl) but may corrode steel Does not increase final strength Most common is calcium chloride (CaCl) but may corrode steel

41 2E8 Materials (Civil Engineering Component) Section A.1Basic Materials 4.Admixtures Water Reducing Admixtures (Plasticisers) Reduces the amount of water required for a given workability Most common is calcium ligno-sulphate Reduces the risk of evaporation cracks Generates evenly dispersed air bubbles in the mix Improves durability against frost and marine environments Volume or air entrainment should not exceed 13% of cement paste Air Entraining Admixtures

42 2E8 Materials (Civil Engineering Component) Section A.1Basic Materials 4.Admixtures Retarding Agents Reduces the rate of evolution of heat Necessary for very large concrete pours Can improve impermeability of concrete in basements and water retaining structures No substitute for sound concrete Water-repelling admixtures

43 2E8 Materials (Civil Engineering Component) Section A.1Basic Materials 4.Admixtures

44 2E8 Materials (Civil Engineering Component) Section A.1Basic Materials 4.Admixtures Foaming Agents Produces highly flowing light concrete Superplasticiser Produces flowing normal concrete with high strength Self-compacting Allows highly flowing cohesive mix with no need for vibration. It can also be self-levelling.


Download ppt "2E8 Materials (Civil Engineering Component) Civil Engineering Materials Department of Civil, Structural and Environmental Engineering Trinity College Dublin."

Similar presentations


Ads by Google