Basic Knowledge

                         Basic Knowledge of civil thing which is required 

* Weight of one cement Bag = 50 kg.

* Standard size of bricks 190mm x 90mm x 90mm or 190mm x 90mm x 90mm

* The no. of Bricks required in 1cum = 500.

* No. of cement bags in 1m^3 = 28.8 bags.

* The curing period of RCC is 28 days.

* The Volume of 50kg cement bag is 1.3 CFT.

* Density of cement = 1440 kg/m^3

* Specific gravity of cement is 3.16g/cm^3,sand is 2.66g/cm^3,Bricks is 2g/cm^3.

* DPC thickness should not be less then 2.5cm.

* Head mason can work 25-30m^3 in a day.

* Floor area occupied by 50kg of Cement bag is 0.3m^2 and H = 018m

* Stirrups in Beams and Ties in column are provided to handle the shear force And also keeps longitudinal bars in position.

* Ties- the Transverse reinforcement provided in column.

* Stirrup - transverse reinforcement provided in beams.

* The weight of first class clay brick should be 3.86kg and it has a crushing strength of     10.5 MN/m^2

* Ld development length

* Grade should be stored in dry place.

* Cement bags should be above minimum 30cm of the Ground.

* Cement bags should not be shocked more than 10 bags in height.

* Cement bags should not be touch the wall.

* RCC column legs should be bent with 9D.

* Main Bar in slab shall not be less than 10mm.

* Min Depth of Foundation Should be 1m.

* Slop of stairs should be b/w 25-40 degree

* The minimum thickness of slab is .125m

* IS 456:2000 is code of Practice for plain and Reinforced concrete.

* And for Steel IS 800:2000 is used for practice.

* The length of each bar from factory is 12m.

* Vibration in freshly made concrete is done to remove the air and bubble in concrete mix.

* Grade of Concrete is denoted as Cement/sand/aggregate[for m20 grade -1:1.5:3]

* D.P.C thickness shouldn't be less than 2.5cm 

* PCC [Plain Cement Concrete ]

* Cantilever Beam has one fixed support and the other end is free.

* And in simply supported beam has a minimum of two supports.

* Starter in column thickness should be b/w 100-200 mm

* c/c means center to center distance

* On Lapping zone stirrups placed closely.

* In Beam Tension Steel bar Lapping  should be in L/8 distance

* In Beam top potion steel bars lapping should be provided after L/3 distance.

* Cement more than 3 months old can't be used for construction.

* Tread in staircase is in between 250 - 300 mm.

* Rise in stairs is in between 150 - 200 mm.

* Washroom slab should not be less than 7ft.

* concrete should be ued within 30 mins. 

* Use single mesh of Reinforcement for residential and double for commercial.

* Lapping of bar should not be provided at the end of the support.

* Use 50 d formula for Lapping length.

* Minimum chair spacing in slab is 1 m.

* For circular column minimum of 6 longitudinal bars are used.

* Water cement ratio should be b/w .45-0.60 of volume.

* The concrete should not be thrown from a height more then 1m.

* M25 grade concrete mostly used for construction of Foundation.

* Min thickness of slab = .125 m

* Chair min: of 12mm dia bar to be used.

* While we Estimating we considering 3-5% wastage of concrete.

* Development length should be provided in plinth and top beam.

* The Riser in Stair in b/w (150-200mm) and Tread (250-300 mm)

* In case we add more water in the concrete mix to increase setting time and leads to form the Crack or honeycomb.

* As per IS 456:2000, Maximum dia of bar used in slab should not exceed 1/8th of the total thickness of the slab.

* M20 grade concrete generally used in concretion of slab.

* The compressive strength of Bricks is 3.5N/mm^2

* Max free fall of Concrete = 1.5 m

* Unit weight of pcc is 24 kN/m^3, Steel is 7850kg/m^3,RCC is 25 kn/m^3.

* The slop or Pitch of the stair should be in between 25-40 degrees.

* The concrete can be lifted to a maximum height of 50m using concrete pumps. 

* Compressive strength of brick is 7.5 N/mm^2

* Vibration in Freshly made concrete is done to remove the air bubble in concrete mix.

* unit weight of steel formula 

         D^2 / 162 in kg /m

*Theodolite least count is 20secs whereas compass least count is 30 mins.

* Lapping shouldn't be provide for the dia more than 36 mm

* Sand having moisture content more than 5% should not be used for Concrete mix.

* N0s. of bars = (length of opposite side /  c/c ) +1

* Lapping of bars not allowed if the dia of bar is more then 36 mm.

* Cube test is carried out for each 30m^3 usage of concrete.

* Bearing Capacity of soil should be maximum compare to Design Load / Structure Load