Qulaity Control of Bridges and Grade Separators.ppt
- 1. Construction, Maintenance and Quality Control of Bridges and Grade Separators “Quality Control of Bridges and Grade Separators” Er.M.Anandaraj,M.E., Assistant Divisional Engineer,(H) Quality Control Subdivision, Chennai
- 2. • Concrete is a versatile construction material. • It is plastic and malleable when newly mixed, yet strong and durable when hardened. • These qualities explain why concrete can be used to build skyscrapers, bridges, sidewalks, highways, houses and dams.
- 3. Why Concrete? • Safety • Cost • Strength • Durability • Availability
- 4. CONCRETE – Constituents Cement 14 - 21 % Fine Aggregate 20 – 30 % Coarse Aggregate 40 – 50 % Water 7 - 15 %
- 7. CONCRETE – Code of Practice Bureau of Indian Standards published the code of practice for concrete (IS : 456) in 1953 - Fourth Revision in 2000 - Fifth Amendment in 2019
- 8. CONCRETE – Specifications Standard Specifications for Roads and Bridges Published by Ministry of Road Transport and Highways (MORTH) - First publication in 1973 - Fifth Revision 2013
- 9. CONCRETE – Guidelines Guidelines Published by Indian Roads Congress
- 10. CEMENT • Factory made material • Checking Grade, Type and Brand • Checking manufacturing week & Year • Checking storage place – IS 4082
- 11. STANDARD SPECIFICATION FOR ORDINARY PORTLAND CEMENT PHYSICAL REQUIREMENTS 1. Fineness 2. Consistency 3. Setting Time 4. Soundness 5. Compressive Strength
- 12. Fineness of Cement IS 4031 I • Finer cement offers greater surface area for hydration and faster strength development. • Fineness is a measure of particle size of Cement • Particle size between 3 to 32 microns are optimum for cement performance • Fine Cement reacts quickly with water • Faster setting & High early strength depends on fineness
- 13. Fineness of Cement IS 4031 Test in two ways By Sieving (90 mic) % retained shall not more than than 10% for Ordinary Cement. Air Permeability method (represented as Specific surface area -m2 /kg)
- 14. Fineness of Cement : IS 4031 - Part 2 Determination of Specific Surface of Cement Blaine Air Permeability apparatus Specific Surface of Cement shall not be less than 225 m2 /kg
- 15. Consistency of Cement : IS 4031 – Part 4 Aim : Determination of Quantity of Water required to produce standard cement paste Apparatus : Vicat apparatus with Plunger (Plunger-10mm dia and 50mm length) Percentage of water corresponds to a consistency which will permit the plunger to penetrate to 5 mm – 7 mm from the bottom of mould
- 16. VICAT APPARATUS
- 17. Initial Setting Time : IS 4031 – Part 5 Aim : Determination of Initial Setting Time Apparatus : Vicat apparatus with Needle The time elapsed between the moment that the water is added to the cement, to the time that the paste starts losing its plasticity. • Initial Setting Time shall not less than 30 minutes
- 18. Final Setting Time : IS 4031 – Part 5 Aim : Determination of Final Setting Time Apparatus : Vicat apparatus and needle with Annular Attachment Final Setting Time shall not more than 600 minutes ( 10 hours )
- 19. FOR FINAL SETTING TIME
- 20. Soundness of Cement : IS 4031 - Part 3 Aim : Determination of Soundness Apparatus : Le Chatelier apparatus (30mm dia & 30mm High) • It Is very important that the cement after setting shall not undergo any appreciable change of volume. • The unsoundness in cement is due to the presence of excess of lime combined with acidic oxide at the kiln. • Expansion not more than 10 mm
- 21. Compressive Strength : IS 4031 – Part 6 Aim : Determination of Compressive Strength Apparatus : Compression testing machine • This is most important properties of hardened cement. • Due to excessive shrinkage and the cracking the strength test are not made on heat cement paste. • Standard sand is used for finding the strength of the cement.
- 22. Compressive Strength : IS 4031 – Part 6 Aim : Determination of Compressive Strength Apparatus : Compression testing machine DAYS COMPRESSIVE STRENGTH (N/mm2 ) 3 23 27 7 33 37 28 43 53 43 GRADE 53 GRADE
- 23. AGGREGATES COARSE AGGREGATES : AGGREGATES RETAINED ON 4.75 MM SIEVE FINE AGGREGATES : AGGREGATES PASSING THROUGH 4.75 MM SIEVE
- 24. AGGREGATE Properties • Specific Gravity • Water absorption • Bulk Density • Gradation
- 25. COARSE AGGREGATE • Particle size distribution • Crushing value • Impact value • Abrasion value • Soundness • Flakiness index • Elongation index
- 26. FINE AGGREGATE GRADING REQIREMENT - IS : 383 TABLE 4 SIEVE SIZE ZONE - I ZONE - II ZONE - III ZONE - IV 10 mm 100 100 100 100 4.75 mm 90 – 100 90 – 100 90 – 100 95 – 100 2.36 mm 60 – 95 75 – 100 85 – 100 95 – 100 1.18 mm 30 – 70 55 – 90 75 – 100 90 – 100 600 micron 15 – 34 35 – 59 60 – 79 80 – 100 300 micron 5 – 20 8 – 30 12 – 40 15 – 50 150 micron 0 – 10 0 – 10 0 – 10 0 – 15 FINE AGGREGATE
- 28. • Iron slag • Copper slag • Steel Slag • Recycled Aggregate Types of Aggregates
- 29. COARSE AGGREGATE
- 30. GRADED COARSE AGGREGATE IS : 383 TABLE 2 IS SIEVE DESIGNATION PERCENTAGE PASSING 40 mm 100 20 mm 90 – 100 10 mm 25 – 55 4.75 mm 0 – 10 FOR 20 mm NOMINAL SIZE
- 31. AGGREGATE CRUSHING VALUE IS : 2386 PART - IV AGGREGATE CRUSHING VALUE SHALL NOT EXCEED : 30 % FOR WEARING SURFACES SUCH AS ROADS & PAVEMENTS 30 % FOR OTHER THAN WEARING SURFACES
- 32. AGGREGATE IMPACT VALUE IS : 2386 PART - IV AGGREGATE IMPACT VALUE SHALL NOT EXCEED : 30 % FOR WEARING SURFACES SUCH AS ROADS & PAVEMENTS 45 % FOR OTHER THAN WEARING SURFACES
- 33. AGGREGATE ABRASION VALUE IS : 2386 PART - IV AGGREGATE ABRASION VALUE SHALL NOT EXCEED : 30 % FOR WEARING SURFACES SUCH AS ROADS AND PAVEMENTS 50 % FOR OTHER THAN WEARING SURFACES
- 34. SOUNDNESS TEST IS : 2386 PART - V • This test is intended to study the resistance of Coarse and fine aggregates to weathering action. • Loss in percentage not more than =10 for Sodium sulphate, 15 for Magnesium sulphate
- 35. • Combined flakiness and Elongation shall not exceed = 40% 25mm - 20mm 20mm - 16mm 16mm - 12.5mm 12.50mm - 10mm 10mm - 6.3mm Flakiness and Elongation Test
- 36. Water • Clean and free from injurious amount of Oil, Acid, Alkali, Sugar, Salt, and Organic materials • Potable water is good for concrete • Sea water is not permitted
- 37. Test Reference Codes Acceptance Standards PH Value IS 456 2000 6 to 8 Chlorides IS 3025(Part 24) 500mg / l. (RCC & PSC) Sulphate IS 3025(Part 24) 400 mg / l. Neutralization with NaOH IS 3025 Maximum = 5 ml. of 0.02 Normal NaOH to Neutralize 100 ml. of water Neutralization with H2 SO4 IS 3025(Part 23) Maximum = 25 ml. of 0.02 Normal H2 SO4 to Neutralize 100 ml. of water Suspended matter IS 3025 (Part 17) 2000 mg./l. max Organic matter IS 3025 (Part 18) 200 mg /l. max Inorganic matter IS 3025 (Part 18) 3000 mg / l. max Water
- 38. Steel (IS 1786) • To determine the ultimate tensile stress, proof stress and elongation using the universal Testing Machine • Use Primary Steels (as per Cl 1009.3.1 Morth Vth)
- 39. Steel (IS 1786) • TMT • CRS • CTD • EQR • TMX • HCRM Quenching and tempering : a two-stage heat-treatment process. Stage one includes hardening (900°C) and then quickly cooled with water or oil. Stage two consists of tempering the material to obtain the desired material properties.
- 41. Coating of Reinforcing Bars •Fusion Bonded Epoxy Coated Rein. – IS 13620 • Hot Dipped Galvanized Bars – IS 12594 Coating of reinforcing bars
- 42. Properties of Steel bars Properties Fe 415 Fe 415 D Fe 500 Fe 500 D Fe 550 Fe 550D Proof Stress Minimum (Mpa) 415 415 500 500 550 550 Ultimate Strength Minimum (Mpa) 485 500 545 565 585 600 Elongation Percentage Minimum (%) 14.5 18 12 16 10 14.50 Steel (IS 1786)
- 43. Seismic Zone Map for Tamil Nadu
- 44. Steel Reinforcement for Structures • As per IRC 112 for Zone III &Zone IV area it is necessary to use HYSD bars having minimum elongation of 14.5%
- 45. • Shall be furnished by the contractor and got approved by the Engineer before start of work. • Bars shall be bent cold to the specified shape and dimensions or as directed by the Engineer using a proper bar bender, operated by hand or power to obtain the correct shape and radii of bends. Bending of Reinforcement
- 46. Form work (IRC 87)
- 47. Welding and Mechanical Coupler
- 48. CONCRETE – Strength development Fresh Stage Concrete is Plastic, workable capable of being moulded Transition Stage Workability reduces, process of setting begins Hardened Stage Concrete becomes stiff and gains enough strength to support load
- 49. CONCRETE – Strength Number refers to Compressive strength of 150 mm cube, cured in water for 28 days expressed in N/mm2 (Mpa) Concrete is designated by its compressive strength only M 30 M refers to Mix Eg :
- 50. Ordinary Concrete Cement Fine Aggregate Coarse Aggregate Ordinary Concrete + + Water +
- 51. Applications of Ordinary Concrete (M 10,M 15,M 20) • Plain concrete works • Lean concrete works • Simple foundations • Foundation for masonry walls • Temporary RCC constructions • Non load bearing structures
- 52. Standard Concrete Ordinary Concrete Chemical Admixture Standard Concrete + (High range water reducers)
- 53. Applications of Standard Concrete (M 25 to M 50) • Reinforced concrete works • Pre stressed concrete works • Prefabricated concrete elements • Load bearing structures
- 54. Achieving High Strength Concrete Conventional Concrete Mineral Admixture Chemical Admixture High Strength Concrete + +
- 55. Applications of High Strength Concrete (M 50 – M 100 ) • High Rise Buildings • Offshore Structures • Nuclear Power Plants • Spill ways of Dams • Long span Bridges • Ultra-thin whitetopping
- 56. MINERAL ADMIXTURES RECOMMENDED BY IS : 456 • Fly Ash • GGBS • Silica Fume • Rice Husk Ash • Metakaolin
- 57. Chemical Admixtures IS 9103 • Compatibility of the admixtures with the cement and any other pozzolans or hydraulic addition shall be ensured by avoiding the following problems. Requirements of large dosage of super plasticizer for achieving the desired workability. Excessive retardation of setting Excessive entrainment of large air bubbles Rapid loss of slump Excessive segregation and bleeding Chemical Admixtures (IS 9103)
- 58. • Transported by the transit mixes or properly designated buckets or by pumping. • Transported within 2 hrs., if excess the time use retarder type admixtures • During hot or cold weather, concrete shall be transported in deep containers RMC (IS 4926)
- 59. Standard slump cone size Top dia = l0 cm Bottom dia = 20 cm. Height = 30 cm Standard tamping rod Length = 0.6 m Dia = 16 mm. Test Procedure Concrete shall be poured in three layers - each layer 25 blows. On removing the cone slowly, the slumped concrete height has to be measured. The difference between this reading and the original height of 30 cm is the slump of concrete. Concrete Workability – Slump Cone IS 1199
- 60. Concrete workability – Slump Test (IS 1199)
- 61. Sl.No Type Slump (mm) 1. (a) Structures with exposed inclined surface requiring low slump concrete to allow proper compaction 25 (b) Plain Cement Concrete 25 2. RCC, structures with widely reinforcement eg. solid column, piers, abutment footing, well steining 40 -50 3. RCC structure with fair degree of congestion of reinforcement eg.Pier and abutment, Caps, Box culvert well curb, well cap, walls with thickness greater than 300 mm 50 - 75 4. RCC PSC structures with highly congested reinforcement eg. Deck Slab Girders, Box Girders, walls with thickness less than 300 mm 75 - 125 5. Under water concreting through tremie eg. Bottom plug, cast- in-situ Pilling 150 - 200 Recommended Slump Value
- 62. Requirement of concrete for Different Exposure Conditions
- 63. • The concrete shall be deposited as nearly as practicable in its original position to avoid re-handling. • The concrete shall be placed and compacted before its initial setting so that it is amenable to compaction by vibration • As a general guidance, the permissible free fall of concrete may not exceed 1.5 m Placing of concrete
- 64. • Concrete shall be thoroughly compacted by vibration or other means during placing and worked around the reinforcement , tendons or duct formers, embedded fixtures and into corners of the formwork to produce a dense homogeneous void free mass having the required surface finish. • When internal vibrators are used, they shall be inserted vertically to the full depth of the layer being placed and ordinarily shall penetrate the layer below for a few centimeters. The vibrator should be kept in place until air bubbles cease escaping from the surface and then withdrawn slowly to ensure that no hole is left in the concrete • IS 2502, IS 2506, IS 2514 Compaction of Concrete
- 65. Compaction
- 66. • The temperature of the concrete at the time of placement should be as low as possible, but in no case more than 35°C. • Use of chilled mixing water • Use of crushed ice or flaked as a part of mixing water. • Sprinkling stockpiles of coarse aggregate with water and keeping them moist. • Limiting temperature of cement to be preferably not in excess of 30°C at the time of use Concrete in hot weather
- 67. • Ensure that the temperature of the concrete does not drop below 4 degrees Celsius in order to prevent this loss of strength. • Delayed setting and hardening, slower rate of gain of strength, • Irreparable loss of strength and durability, if freezing of concrete takes place at early ages, when it is still in plastic state. Even one cycle of freezing of concrete during the prehardening period may lower the compressive strength by 30 to 50 percent, Concrete in cold weather
- 68. • Water Curing • Steam Curing • Curing Compounds After placing and during the first stages of hardening, concrete shall be protected from harmful effects of sunrays, drying winds, cold, running water, shocks, vibrations, traffic including construction traffic etc. Curing of concrete
- 69. Strength of Concrete Sample Strength of Concrete in Structure 1 Sample = 3 Cubes Acceptance Criteria for Strength of Concrete
- 70. Minimum Frequency of Sampling Quantity of Concrete (m3 ) Number of Samples 1 - 5 1 6 – 15 2 16 – 30 3 31 – 50 4 51 and above 4 + 1 for each additional 50 m3 or part
- 71. Sampling of Fresh Concrete • Collect Samples from not less than 5 well-distributed positions immediately after discharge • Quantity of sample shall not be less than 0.02 m3 • Avoid edge of the concrete mass to avoid segregation
- 72. Making and Curing Test Specimen • Mould shall be thinly coated with oil • Concrete shall be filled in 3 layers Each layer 5 cm deep • Compaction with tamping bar Number of strokes per layer : 35
- 73. Making and Curing Test Specimen • Specimen shall be stored at safe place at 220 c to 320 c for 24 hours • After 24 hours, specimen shall be stored in clean water at 270 c ± 20 c until the date of testing
- 74. Testing of Concrete specimen • Specimens stored in water shall be removed from the water • Surface water shall be wiped off • Specimens shall be tested while they are in the Saturated Surface Dry condition
- 75. Testing of Concrete specimen • Load shall be applied perpendicular to Cast direction •Rate of loading : 5.25 kN/sec • Load shall be applied until the specimen breaks down Load at Failure •Compressive Strength = Cross sectional area Top Top
- 76. Acceptance Criteria Fc1 = Strength of cube 1 Fc2 = Strength of cube 2 Fc3 = Strength of cube 3 Fc1 + Fc2 + Fc3 Fc mean = ------------------- 3 Fc mean > (Fck + 3) The values of Fc1 , Fc2 and Fc3 should be within ± 15 % of Fc mean
- 77. Acceptance Criteria for M 30 Fc1 = 33 MPa Fc2 = 36 MPa Fc3 = 28 MPa Fc mean = 32.33 Mpa 15 % of 32.33 = 4.85 MPa 32.33 – 4.85 = 27.48 MPa 32.33 + 4.85 = 37.18 MPa Fck = 30 Mpa Fck + 3 = 33 MPa Fc mean is less than (Fck + 3) Not Accepted Fc1, Fc2 and Fc3 are between 27.48 Mpa and 37.18 Mpa Test Result is valid
- 78. Sample 1 Sample 2 Sample 3 Sample 4 Group - I For 50 m3 of Concrete 4 Samples are required
- 79. Factors affecting Strength of Concrete •Water/Cement Ratio •Cement Content •Aggregate/Cement Ratio •Type of Aggregate •Placing & Compaction •Curing condition •Age of Concrete •Environmental Condition
- 80. Strength of concrete in structure If cube strength fails ?
- 81. • Penetration method • Rebound hammer method • Pull out test method • Ultrasonic pulse velocity method • Radioactive methods • Half Cell Potentiometer etc., Non Destructive Tests
- 82. • The probe test produces quite variable results and should not be expected to give accurate values of concrete strength. • It has, however, the potential for providing a quick means of checking quality and maturity of in situ concrete. Penetration Test
- 83. Rebound Hammer (IS 516 P5 Sec4) POSITION OF REBOUND HAMMER - VERTICALLY UPWARDS
- 85. Pull out Test Method • A pull-out test measures, with a special ram, the force required to pull from the concrete a specially shaped steel rod whose enlarged end has been cast into the concrete to a depth of 3 in. • Although pullout tests do not measure the interior strength of mass concrete, they do give information on the maturity and development of strength of a representative part of it. Pull Out Test Method
- 86. Ultrasonic Pulse Velocity Test (IS 516 P5 Sec1)
- 87. Ultrasonic Pulse Velocity Concrete Quality Grading Pulse Velocity (km/s) Quality Above 4.4 Excellent 3.75 to 4.4 Good 3.0 to 3.75 Doubtful Below 3.0 Poor
- 88. • Radioactive methods of testing concrete can be used to detect the location of reinforcement, measure density and perhaps establish whether honeycombing has occurred in structural concrete units. Radioactive Method
- 89. GPR & Profometer 650AI
- 90. Concrete Core Test (IS 516 P4) Fixing the core cutting machine Drilling the concrete
- 91. Concrete Core Test Drilling in process Drilling completed
- 92. Concrete Core Test Concrete core Levelling
- 94. Concrete Core Test Fixing in machine Testing
- 95. ACCEPTANCE CRITERIA I ) AVERAGE EQUIVALENT CUBE STRENGTH OF CORE = II ) STRENGTH OF ANY INDIVIDUAL CORE = COMPRESSIVE STRENGTH OF CORES 85 % of CUBE STRENGTH of SPECIFIED GRADE 75 % of CUBE STRENGTH of SPECIFIED GRADE
- 96. ACCEPTANCE CRITERIA If the Concrete is not able to meet any of the STANDARDS OF ACCEPTANCE, the Structure is to be Investigated
- 97. • Strength and durability of concrete depends on many factors • To achieve a strong and durable concrete structure, High Intention Sincere Effort Intelligent Direction and Skillful Execution are needed Summary of main points
- 98. THANK YOU