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  1. 1. PARTIAL REPLACEMENT OF CEMENT BY MARINE CLAY FOR SUSTAINABLE CONCRETE PRODUCTION GUIDED BY : SREEREKHA. K ASST PROFESSOR DEPT OF CIVIL ENGINEERING ROLL NUMBER :LKME19CE056 BATCH : S7 CE A PRESENTED BY : MEGHA.M
  2. 2. INTRODUCTION • Concrete is the second most widely used material in the world. • However, environmental concerns are raised for the high carbon emission during cement production. • Concrete production contributes about 7% of the global CO2 emission. • A practical strategy to lower the environmental impact is to replace cement by locally available supplementary cementitious materials (SCMs). • Amongst various SCMs such as fly ash and slag, calcined clay is considered as more viable option due to its wide availability. PARTIAL REPLACEMENT OF CEMENT BY MARINE CLAY FOR SUSTAINABLE CONCRETE PRODUCTION 2
  3. 3. PARTIAL REPLACEMENT OF CEMENT BY MARINE CLAY FOR SUSTAINABLE CONCRETE PRODUCTION 3 • Marine clay, generated from excavation works and dredging activities, is normally discarded as it is too soft as backfill materials. • With the addition of cement and additives, this marine clay can be transformed into highly flowable grout material. • The purpose of back-fill and soil stabilization and thus a large amount of marine clay can be reused. • Many major infrastructure constructions are currently being undertaken in different places
  4. 4. PARTIAL REPLACEMENT OF CEMENT BY MARINE CLAY FOR SUSTAINABLE CONCRETE PRODUCTION 4 • The preliminary site investigation and geophysical survey revealed that the Singapore marine clay at Changi consists of the upper and lower marine clay layers. • These soft to medium stiff clay members are recent deposits of estuarine origin. They are separated by a layer of medium stiff to stiff clay with a thickness of 2–5 m. • This layer, locally termed as intermediate clay, is reddish and is believed to be the desiccated crust of the lower marine clay.
  5. 5. MANUFACTURING PROCESS •Marine clay was collected from a construction site • After being dried at 50 °C for 72 hours under air recirculation, •clay samples were ground in a ball mill for 30 minutes. •The calcination process was performed by putting clayfilled crucibles in a furnace (ELITE laboratory chamber furnace) and heating from room temperature up to the designed temperature at a rate of 10 °C/min. •The temperature maintained for 1 hour, followed by removing the crucibles quickly and spreading on a metal plate to cool at ambient temperature. PARTIAL REPLACEMENT OF CEMENT BY MARINE CLAY FOR SUSTAINABLE CONCRETE PRODUCTION 5
  6. 6. •Add the sample with cement and water aggregate. •The mixture of concrete with marine clay is thus made. PARTIAL REPLACEMENT OF CEMENT BY MARINE CLAY FOR SUSTAINABLE CONCRETE PRODUCTION 6 Production of sustainable cement (S. Basack and R. D. Purkayastha et al )
  7. 7. PROPERTIES OF MARINE CLAY PHYSICAL PROPERTIES OF MARINE CLAY PARTIAL REPLACEMENT OF CEMENT BY MARINE CLAY FOR SUSTAINABLE CONCRETE PRODUCTION 7 SI NO PROPERTIES VALUE 1 Natural Moisture Content 112 2 Specific Gravity 2.62 3 Grain Size Distribution Sand % 2 Silt % 54 Clay % 44 4 Liquid Limit % 156 5 Plastic Limit % 34 6 Plasticity Index % 122 7 Shrinkage Limit % 10.71 8 pH 7.53 9 Coefficient of Consolidation (cm²/sec) 5.65 x 10-4 10 Compression Index 0.64 11 Unconfined Compressive strength, KPa 4
  8. 8. GEOTECHNICAL PROPERTIES  shear strength Upper marine clay - 10 and 30 kPa.  Lower marine clay - 30 and 60 kPa.  Sensitivity - 3 to 8 Fraction of the finer - 78% and 88% Permeability - 1.10 - 2.44 × 10-9 m/s  Maximum dry density - 1.5 - 1.6 g/cm3  Optimum moisture content - 18.2% - 25%. PARTIAL REPLACEMENT OF CEMENT BY MARINE CLAY FOR SUSTAINABLE CONCRETE PRODUCTION 8
  9. 9. VISUAL CHARACTERISTICS The following properties are observed from visual classification in dry condition: Colour - Black colour. Odour - Odour of decaying vegetation. Texture - Fine grained. Dry strength - Medium. Dylatancy - Less Sluggish. Plasticity - Highly plastic. PARTIAL REPLACEMENT OF CEMENT BY MARINE CLAY FOR SUSTAINABLE CONCRETE PRODUCTION 9
  10. 10. GRAIN SIZE DISTRIBUTION PARTIAL REPLACEMENT OF CEMENT BY MARINE CLAY FOR SUSTAINABLE CONCRETE PRODUCTION 10 Grain size distribution curve (S. Basack and R. D. Purkayastha et al )
  11. 11. CHEMICAL AND MINERALOGICAL PROPERTIES Organic matter content - 7% Cation exchange capacity - 30.8 m.eq/100 gm of soil. Exchangable ferrous ion pH Carbonate content - 0.005%. - 7.2. - 23% PARTIAL REPLACEMENT OF CEMENT BY MARINE CLAY FOR SUSTAINABLE CONCRETE PRODUCTION 11
  12. 12. MINERAL COMPOSITIONS OF MARINE CLAY •marine clay consist of several highly compressible clay minerals such as vermiculite and chlorite at different percentages. •Those minerals are responsible for the compressible and swelling behaviour exhibited by marine clay. •Their percentages seems to control the degree of compressibility and swellability of the soil. •The mineral content in marine clay depends on the depth and location of the sample, aging of deposition etc. •Last but not least, montmorillonite is found to be the most influenced clay mineral in marine clay. PARTIAL REPLACEMENT OF CEMENT BY MARINE CLAY FOR SUSTAINABLE CONCRETE PRODUCTION 12
  13. 13. MATERIAL CHARACTERIZATION •The marine clay has a higher fraction of coarse grains than cement. • The clay is thermally activated without any pre-treatment such as separation of clayed particle from the raw material. •The marine clay composes of gravel, sand and silt and they come in varying particle sizes. PARTIAL REPLACEMENT OF CEMENT BY MARINE CLAY FOR SUSTAINABLE CONCRETE PRODUCTION 13
  14. 14. XRD PATTERNS •The strong intensity of the quartz peak can be observed in the cement paste prepared with calcined marine clay and its intensity increases with an increase in replacement ratio. •Comparing the signature of the portlandite in cement paste with calcined marine clay against the OPC paste with defined portlandite peak, there is an obvious reduction of the portlandite peak when cement is partially replaced by marine clay, indicating that calcined marine clay plays an important role in the consumption of the portlandite phase. Furthermore, it can be observed that the intensity of portlandite is progressively decreased with an increase in calcined marine clay replacement. PARTIAL REPLACEMENT OF CEMENT BY MARINE CLAY FOR SUSTAINABLE CONCRETE PRODUCTION 14
  15. 15. COMPRESSIVE STENGTH OF MORTAR •The compressive strength development for different mortar mixes. •At every testing age, the reference mortar with 100% cement shows the highest strength and reaches 39 MPa at 28 days. • Meanwhile, mortar with 30% inert filler exhibits the lowest strength at all testing ages, due to the cement dilution. •Mortars incorporating calcined marine clay show intermediate strength between these two reference mixes. •The strength would also be affected by the particle fineness of the calcined marine clay, on top of the pozzolanic reactivity. PARTIAL REPLACEMENT OF CEMENT BY MARINE CLAY FOR SUSTAINABLE CONCRETE PRODUCTION 15
  16. 16. MICROSTRUCTURE •Compares the microstructural observations in OPC mortar and MC800 mortar. •In the OPC system, typical cement hydration products can be easily identified. •With 30% OPC replaced by calcined marine clay, the change in the morphology is very obvious. •The microstructure is more homogeneous and the crystal phase of Portlandite and needle ettringite can hardly be observed. •As a result, the calcined clay grain shows a very dense bond with its surrounding hydration products. PARTIAL REPLACEMENT OF CEMENT BY MARINE CLAY FOR SUSTAINABLE CONCRETE PRODUCTION 16
  17. 17. EFFECT OF CALCINED MARINE CLAY ON CEMENT HYDRATION •The heat evolution curves within 24 hours for different pastes are presented in Figure •Compared to the paste with 100% cement, paste with 30% cement replacement by quartz filler does not deviate much with respect to both the times at which the reaction starts and the rate at which the reaction develops. •The addition of calcined marine clay increases the hydration rate for both the second and third peaks corresponding to the hydration of C3S and C3A, respectively. •Compared with the OPC heat curve, the third peak is higher than the second peak for paste with calcined marine clay, implying that the calcined marine clay has greater accelerating effect on C3A hydration than C3S hydration. PARTIAL REPLACEMENT OF CEMENT BY MARINE CLAY FOR SUSTAINABLE CONCRETE PRODUCTION 17
  18. 18. Hydration rate of different pastes.( Juntao Dang, Hongjian Du, Sze Dai Pang et al) PARTIAL REPLACEMENT OF CEMENT BY MARINE CLAY FOR SUSTAINABLE CONCRETE PRODUCTION 18
  19. 19. MARINE CLAY UTILIZATION IN CONCRETE PRODUCTION •Portland cement (PC) was partially replaced with 0-30% marine clay •This paper concludes that using ground marine clay can reduce the use of cement and the associated energy demand and impact on air pollution and CO emission. •At 30% marine clay content compressive strength of concrete is higher than that of the control. Above 30% marine clay the strength substantially decreases. PARTIAL REPLACEMENT OF CEMENT BY MARINE CLAY FOR SUSTAINABLE CONCRETE PRODUCTION 19
  20. 20. COMPARISON OF CONVENTIONAL CONCRETE AND MARINE CLAY MIXED CONCRETE Conventional Concrete Marine clay mixed concrete • Cement, sand, stone and water • Durable • Less strength • Higher construction cost • Less compressive strength • Less workability • Less initial setting time • Heavy weight concrete •Cement, marine clay, stone and water •Very high durability •More strength •Lower construction cost •More compressive strength •More workability •More initial setting time •Light weight concrete PARTIAL REPLACEMENT OF CEMENT BY MARINE CLAY FOR SUSTAINABLE CONCRETE PRODUCTION 20
  21. 21. ADVANTAGES AND DISADVANTAGES OF VARIOUS CONSTRUCTION SOIL 1) Peat Advantages: •Environmentally friendly •It used in walls act as an air cleaner •Peat blocks in walls create sound and thermal proofing spaces. Disadvantages: •Poor choice for supporting structures •Needs high technical expertise to use peat correctly •Sourcing peat blocks can be a challenge PARTIAL REPLACEMENT OF CEMENT BY MARINE CLAY FOR SUSTAINABLE CONCRETE PRODUCTION 21
  22. 22. 2)Clay Advantages: •Ideal material for tropical condition •Durable clay brick add value and style •Insulation properties help save energy costs Disadvantages : •Poor choice for foundation •Highly susceptible to dampness •Require skilled craftsmen for correct use PARTIAL REPLACEMENT OF CEMENT BY MARINE CLAY FOR SUSTAINABLE CONCRETE PRODUCTION 22
  23. 23. 3)Silt Advantages: •Fertile soil •Better water holding capacity •Easier to work with than clay Disadvantages: •Weakness the foundation due to expansion •Unsuitable for most constructions PARTIAL REPLACEMENT OF CEMENT BY MARINE CLAY FOR SUSTAINABLE CONCRETE PRODUCTION 23
  24. 24. 4)Sand Advantages: •Supports heavy loads,hence suitable for construction •Offers good drainage •Does not contain organic or impure compounds Disadvantages: •The sand particles can wash away, leaving gaps underneath the foundation. •Quality sand is expensive PARTIAL REPLACEMENT OF CEMENT BY MARINE CLAY FOR SUSTAINABLE CONCRETE PRODUCTION 24
  25. 25. 5)Loam Advantages: •Ideal for construction as it holds water at a balanced rate •Manages air humidity if used as a layer on the inside walls •Ideal to build walls when mixed with straw Disadvantages: •Effective in construction only if organic or miscellaneous soils aren’t mixed •Better than clay but worst than sand PARTIAL REPLACEMENT OF CEMENT BY MARINE CLAY FOR SUSTAINABLE CONCRETE PRODUCTION 25
  26. 26. 6)Rock Advantages: •High weight-bearing capacity •Ideal for supporting foundations •Practical,economical,non-toxic and reliable Disadvantages: •Effective material only if leveled properly •Right grain size is not found naturaly PARTIAL REPLACEMENT OF CEMENT BY MARINE CLAY FOR SUSTAINABLE CONCRETE PRODUCTION 26
  27. 27. ADVANTAGES OF CONCRETE WITH MARINE CLAY •Supports heavy loads •Heaviest of soil types • Stable and durable. •Weather-resistant. •Earthquake-proof. •As a soundproofing material. PARTIAL REPLACEMENT OF CEMENT BY MARINE CLAY FOR SUSTAINABLE CONCRETE PRODUCTION 27
  28. 28. •Fire-resistant. • Easily available • Very high durability •It can be manufactured to the desired strength with an economy. PARTIAL REPLACEMENT OF CEMENT BY MARINE CLAY FOR SUSTAINABLE CONCRETE PRODUCTION 28
  29. 29. DISADVANTAGES •Holds onto water •The sand particles can wash away, leaving gaps underneath the foundation. • Less ductile •The weight is high compared to its strength •Compared to other binding material, the tensile strength is relatively low. PARTIAL REPLACEMENT OF CEMENT BY MARINE CLAY FOR SUSTAINABLE CONCRETE PRODUCTION 29
  30. 30. CONCLUSION •The soil found in the ocean bed is classified as marine soil. • It can even be located onshore as well. •The properties of marine soil depend significantly on its initial conditions. •The properties of saturated marine soil differ significantly from moist soil and dry soil. •Marine clay is microcrystalline in nature and clay minerals like chlorite, kaolinite and illite and non clay minerals like quartz and feldspar are present in the soil. •The soils have higher proportion of organic matters that acts as a cementing agent. •Explored the use of marine clay to create lightweight aggregates for lightweight concrete. PARTIAL REPLACEMENT OF CEMENT BY MARINE CLAY FOR SUSTAINABLE CONCRETE PRODUCTION 30
  31. 31. REFERENCE . 1.Du, H., Pang, S.D., 2018. Value-added utilization of marine clay as cement replacement for sustainable concrete production. J. Clean. Prod. 198, 867e873. 2.Juntao Dang, Hongjian Du, Sze Dai Pang(2020),Hydration strength and microstructure evaluation of eco-friendly mortar containing waste marine clay. 3.Anjaneya Dixit, Hongjian Du, Sze Dai Pang (2020)Marine clay in ultra high performance concrete for filler substitution. 4. M.W. Bo, A. Arulrajah, P. Sukmak, S. Horpibulsuk, Mineralogy and geotechnical properties of Singapore marine clay at Changi, Soils Found 55 (2015) 600-613. PARTIAL REPLACEMENT OF CEMENT BY MARINE CLAY FOR SUSTAINABLE CONCRETE PRODUCTION 31
  32. 32. 5. K. Laursen, T.J. White, D.J.F. Cresswell, P.J. Wainwright, J.R. Barton, Recycling of an industrial sludge and marine clay as light-weight aggregates, J Environ Manage 80 (2006) 208-213. 6. N. Shirlaw, T.S. Tan, K.S. Wong, Deep excavations in Singapore marine clay, In: 5th International Symposium on Geotechnical Aspects of Underground Construction in Soft Ground, Amsterdam, Netherland, (2006) 13-28. 7. A.H.M. Kamruzzaman, S.H. Chew, F.H. Lee, Structuration and destructuration behavior of cement-treated singapore marine clay, J.Geotech. Geoenvironmental Eng. 135 (2009) 573–589. PARTIAL REPLACEMENT OF CEMENT BY MARINE CLAY FOR SUSTAINABLE CONCRETE PRODUCTION 32
  33. 33. PARTIAL REPLACEMENT OF CEMENT BY MARINE CLAY FOR SUSTAINABLE CONCRETE PRODUCTION 33

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