Basic 100 Important Points for Civil Site Engineers & Supervisors
1.Minimum diameter of bars used in slab = 8mm.
2. Minimum diameter of bars used in column = 12mm.
3. Minimum number of bars used in square or rectangular column = 4 bars.
4. In Cantilever Beam Tension Zone is Up & compression zone is Below where as in simply supported Beam Compression Zone is above & Tension is Below
5.Lapping is not allowed for the bars having diameters more than 36 mm.
6. Chair spacing maximum spacing is 1.00 m (or) 1 No per 1m2.
7. For dowels rod minimum of 12 mm diameter should be used.
8. Chairs minimum of 12 mm diameter bars to be used.
9. Longitudinal reinforcement not less than 0.8% and more than 6% of gross C/S.
10. Minimum bars for square column is 4 No’s and 6 No’s for circular column.
11. Main bars in the slabs shall not be less than 8 mm (HYSD) or 10 mm (Plain bars) and the distributors not less than 8 mm and not more than 1/8 of slab thickness.
12. Minimum thickness of slab is 125 mm.
13. Dimension tolerance for cubes + 2 mm.
14. Density of Construction Material
| Material | Density |
| Bricks | 1600 – 1920 kg/m3 |
| Concrete block | 1920 kg/ m3 |
| Reinforced concrete | 2310 – 2700 kg/ m3 |
15. Maximum diameter of bars used in slab = 1/8 × thickness of slab.
16. Free fall of concrete is allowed maximum to 1.50m.
17. Water absorption of bricks should not be more than 15 %.
18. PH value of the water should not be less than 6.
19. Compressive strength of Bricks is 3.5 N / mm2.
20. In steel reinforcement binding wire required is 8 kg per MT.
21. In soil filling as per IS code, 3 samples should be taken for core cutting test for every 100m2.
22. Samples from fresh concrete shall be taken and at least a set of 6 cubes of 150mm shall be prepared and cured. 3 Cubes each at 7 days and 28 days shall be tested for compressive strength. The test results should be submitted to engineer for approval. If results are unsatisfactory necessary action/rectification/remedial measures has to be exercised.
23. Water used for both mixing and curing shall be clean and free from injurious amounts of oils, acids, alkali, salts, sugar and organic materials or other substances that may be deleterious to concrete or steel. The PH. shall be generally between 6 and 8.
24. Lap length for M20 concrete:
Columns – 45d
Beams – 60d
Slabs – 60d
25. Standard size of brick = 190mm×90mm×90 mm = 19cm×9cm×9cm.
26. A good brick clay contains 20 to 30% of alumina, 50 to 60% of silica and the remaining constituents are Lime, Magnesia, Sodium, Potassium, Manganese and iron oxide.
27. Colour of good brick is deep red, cherry or copper coloured.
28. Compressive strength of bricks is 3.5 N/mm2.
29. Ordinary Portland cement consists of 62 to 67% of Lime.
30. The initial setting time of ordinary portland cement should not be less than 30 minutes.
31. The final setting time of ordinary portland cement should not be more than 10 hours.
32. Initial and Final setting time of cement is determined by Vicat’s apparatus.
46. The normal consistency of portland cement is about 25%.
47. When concrete is to be laid under water, Quick setting cement is used.
48. Maximum free fall of concrete allowed to 1.50m.
49. Curing time of RCC Members for different types of cement
Super Sulphate cement: 7 days Ordinary Portland cement
OPC: 10 days
Minerals & Admixture added cement: 14 days
50. Deshuttering Period of RCC member
| RCC Member | De-shuttering time |
| For columns, walls, vertical form works | 16-24 hrs. |
| Soffit formwork to slabs | 3 days (props to be refixed after removal) |
| Soffit to beams props | 7 days (props to refixed after removal) |
| Beams spanning upto 4.5m | 7 days |
| Beams spanning over 4.5m | 14 days |
| Arches spanning up to 6m | 14 days |
| Arches spanning over 6m | 21 days |
51. Test On Fresh Concrete
(a). Slump Test – Workability. (b). Compacting Factor. (c). Vee-Bee Test.
52. Test On Hardened Concrete
(a). Rebound (Schmidt) Hammer Test. (b). Ultrasonic Pulse Velocity Test.
53. The excess of silica in the clay makes the brick brittle and weak.
54. Process of manufacturing of bricks consists of Preparation of brick clay, Moulding bricks, Drying of bricks and Burning of bricks.
55. Moulding of bricks may be hand moulding or machine moulding.
56 .The burning of dry bricks is done either in clamp or in a kiln.
57. The ingredients of ordinary cements are Lime, Silica, Alumina, Calcium sulphate, Iron oxide, Magnesia, Sulphur & Alkali’s.
58. Ordinary Portland cement consists of 62 to 67% of Lime.
59.Slump Range of concrete
| Concrete Mixes | Slump range in mm |
| Columns, Retaining walls | 75-150 mm |
| Beams & Slabs | 50-100 mm |
| CC Pavements | 20-30 mm |
| Decks of bridge | 30-75 mm |
| Vibrated Concrete | 12-25 mm |
| Huge Mass constructions | 25-50 mm |
60. Electrical conduits shall not run in column.
61. Earth work excavation for basement above 3 m should be stepped form.
62. Any back filling shall be compacted 95% of dry density at the optimum moisture content and in layers not more than 200 mm for filling above structure and 300 mm for no structure.
63. soling is specified the soling stones shall be laid at 45° to 60° inclination (and not vertical) with interstices filled with sand.
64. A set of cube tests shall be carried out for each 30 cum of concrete / each levels of casting / each batch of cement.
65. Water cement ratio for different grades of concrete shall not exceed 0.45 for M20 and above and 0.50 For M10 / M15.
66. For concrete grades M20 and above approved admixture shall be used as per mix design requirements.
67.Cement shall be stored in dry places on a raised platform about 200mm above floor level and 300mm away from walls. Bags to be stacked not more than 10 bags high in such a manner that it is adequately protected from moisture and contamination.
68. Cube Quantity
| Quantity of Concrete | No. of cubes required |
| 1 – 5 m3 | 1 No’s |
| 6 0 15 m3 | 2 No’s |
| 16 – 30 m3 | 3 No’s |
| 31 – 50 m3 | 4 No’s |
| Above 50 m3 | 4 + 1 No’s of addition of each 50 m3 |
69. Height of window = 2.1m.
70. Minimum thickness of lintel = 15cm
71. 1 bag of cement = 1.25 cubit feet = 0.0347 cubic meter.
72. No. of cement bags in 1m^3 = 28.8 bags.
73.Civil Site Engineer Responsibilities on Construction Site:
The Following are some important duties and responsibilities of civil site engineer has to done on construction site.
- Interpretation of Drawing
- Preparing Bar Bending Schedule
- Allotting Work to Labors
- Supervision of Construction Work
- Preparing Schedule of Material Used and Available
- Plotting Line – Level on Construction Site
- Preparing Work Chart Schedule
- Checking Steel Work of Slab, Beam, & Column Before Concreting
- Supervision Of The Curing Process
- Supervision Of The Curing Process
- Keeping Note of Each and Every Casting Work
- Much Other Work
74.What Is BoQ?
BoQ means bill of quanity is a document prepared by a cost estimator to calculate the exact costing of project work by multiplying item work by their rate. It is the most important document for tendering and contracting. Bill of quantity gives an idea about the cost of a project that is tendering firm willing to offer.
75.Top Civil Engineering Software
AutoCAD
SAP 2000
Staad Pro
ETABS
Primavera
Revit
ARCGIS for Surveying
3DS Max – Modeling
MX Road – Road Design and Analysis
Google Sketch UP
StormCAD ( storm sewer design )
WaterCAD ( is a software extensively utilized for hydraulic and water quality modeling applications )
Microsoft Project (MS Project)
Easy-Pro Builders Estimator
STACK Takeoff & Estimating Software
76.Pcc-profile corrective course also
77. curing -protecting the freshly concreted surface from water evaporation.
78. scaffolding -supporting system for form work.
79. Ponding-keeping water over a fresh floor etc.
80.splicing-giving lap to steel for further heights.
81. Casting- concreting
82. Admixture- chemicals used for accelerating or reducing water content for workability of concrete.
83. schedule-of bar bending or work
84. Dressing-cutting and make plain the earth’s surface for placing pccaggregate – sand or metal.
85. Reinforement-steel used for rcc.
86. Masonry-constructing brick,block and stone walls.
87. mortar-cement and sand mix.
88.Sealant : A flexible, rubbery type of material that is used to seal gaps in a joint.
89.Drywall: A panel made from gypsum plaster that is wrapped in cardboard. It is commonly used as a fundamental material for framing a building.
90.Skirting: Material that covers up the joint between the floor and a wall in the interior of a building, for aesthetic purposes.
91.Monocrete Construction: A construction method that uses precast concrete panels which are bolted together to make concrete structures.
92.Weight of Bar is calculated using formula D2/162 (D = Dia of bar in mm)
93. The No. of Bricks required for 1m3 of Brick masonry are 550 bricks.
94.What is the Validity of use of Cement?
It is 3 months from Manufacturing
95.What is Segregation of Concrete? and why its caused?
The separation of sand, cement, aggregates in concrete is called
Separation of Concrete.
Its caused due to improper water cement ratio.
Also caused for poured above 1.5 height.
96.Calculations for no of stirrup in a abeam?
Clear Span/ c/c Spacing+1
97.What is the angle of staircase flight?
It is between 25 degree to 40 degree.
98.How much bricks need for 115 mm thick brick work?
56 nos / Sqm
99.How much bars should be lapped in a bar bending zone?
Not more than 50%
100.What is the minimum Hook length for bars?
It is 9D. (D-is dia of bar)