Civil engineering knowledge

Road construction take long time ? Because From rugged dirt paths to modern super highways roads are one of those consistent background characters in nearly every person’s story. And, if you’ve ever been a driver, I know another similar character in your life road construction. Most of us love having wide, smooth roadwaysto take us to work to home and everywhere else we travel. But, we’re hardly ever excited to see aconstruction project starting on our favorite roadway. I’m here to change that  or least to try. I love construction  always have and whenit happens along my commute, I love it even more because I get to see the slow but steady progress each day. And, I think  or at least I hope  that ifyou can know a little bit more about what’s going on behind those orange cones, you might appreciate it a little more as well. we’re talking about earthwork for roadways. The first roads in history were probably formedas people or animals followed the same trail long enough to tamp down the

In this Article I will discuss about behaviour of cement concrete using alternative materials. The requirement of concrete aggregate in India is large corresponding to currentannual production of cement of 300 million tons total requirement of coarse,and fine aggregate for use in cement concrete mortar and plasters of about1,500 metric tons per year is a safe estimate. there is difficulty inobtaining natural aggregates within economic distances. search for alternatesources of aggregates thus assumes importance. one such alternative isrecycled concrete aggregate derived from construction and demolition wastes, whichallow conservation of natural resources and land. aggregate in concrete constructions typically account for 75 percent of the total volume. the majorityof concrete constructions till date essentially resort to aggregatematerials derived from natural resources conforming to is 383.  However due to the need of conserving natural resources and issues relating to sustainabilitye

Unit weight of concrete - RCC- 2500kg/cum & PCC - 2400kg/cum Steps involved in concrete process :- Batching Mixing Transporting Placing Compacting Trapezodial footing volume formula:-         (L*B*H)+{h/3*(A1+A2+√A1A2)} Standard list count of theodolite is 20' In plastering first coat is known as under coat What is the meaning of M50 ? M= mix 50= characteristic compressive strength of cube size is 150 mm *150 mm * 150 mm after 28 days of curing. Unit is N/sqmm Instrument used for specific gravity is  HYDROMETER Size of mould to check compressive strength of cement is 70.6mm* 70.6mm*70.6mm Main bar always a price of direction Distribution bar always apply longer direction Weight of concrete cube (150mm*150mm*150mm) = 8.1 kg

 What is segregation ? Separation of cement sand from aggregate in the concrete. water cement ratio is not proper or As per  IS code height  more than 1.5 meters also segregation. What is bleeding ? Water comes out to the surface of concrete is called bleeding.  It also a type of segregation.   Function of stirrups ? To regist shear force and positioning the main reinforcement. What is the function of foundation? To increase the suitability of structure. What is the 3 4 5 method ?  It is used to set up the plane at right angle. Full form of DPC ?  Damp proof course Minimum die of bored cast insitu pile ? As per IS 2911 part 1 section 2  =  450 mm. Factor used to convert weight to dry volume of concrete ?    Is 1.54   Example :-   if a column wet volume is 3 cum than the dry volume = 3* 1.54= 4.62 cum

What's cement ? Cement is an extremely ground material having adhesive and cohesive properties which provide a binding medium for the described ingredients. Cement can be manufacture by two process. Dry process ( modern technology ) Wet process (old technology ) All the cement plants set up after 1980 use the dry process for manufacturing of cement. Grade    of    cement ? 33 grade - mainly for plaster & masonry work 43 grade - mainly for RCC & RMC ( ready made concrete ) 53 grade- mainly for Bridge, road , subway How much cement bags in 1 cum :-  Density/ unit weight = 1440/ 50                                        = 28.8 bags Volume of bag in 1 cum  Volume* density = mass => V = 50/1440 => V = 0.0347cum Filed test of cement :- grey colour with a light greenish shade cement should feel smooth when touched between finger It should be free from lumps Laboratory test of cement :- Chemical composition test Normal consistency test Initial setting time test Final setting

Hacking on column :- 50 nos in 1sqfeet or 500 nos in 1sqmeter Cover blocks center to center distance :- 600 mm to 1 meter Beam shall not have width less than 200mm For 750mm depth beam provide :- Side Face Reinforcement & also called STIFFNOR Width to depth ratio of beam should be more then 0.3 Yoke interval in column should be 600 m / 2feet Diameter of needle for compaction in column = 40mm Why   steel   always   circular ?       Because circular patterns stress distribution equally. What slope you will provide if you are constructing staircase according IS 456 ?   Answer :- 25° to 40° What's the least count of theodolite of compass ? Theodolite least count is 20 second Compass least count is 30 minute

Why   cover   blocks    used   in   Reinforcement :- To maintained specified distance between Rebars & shuttering. To protect Reinforcement from corrosion. To provide Thermal insulation. Lapping in Tension :-                 L = 50D to 60D (D= diameter of bars) Lapping in compression :-              L = 24D No. Of stirrups calculation :-     { Clear span/center to center spacing}+1 Minimum Hook length of stirrups :- 9D(90mm) Deflection means :- Temporary displacement Deformation means :- permanent displacement Stirrups hook angle should be 135° MS bar larger than 36mm diameter should not be lapped. if it's than welding is referred. No lapping should be placed in tension zone. The longitudinal bar should be bent at 90° & bent length should not be less than 18"or 1.5 feet. End hook angle of longitudinal bars of columns & beam should be 90° More than 50% of bar should not be lapped in one zone. The length of hook should not be less than 12d. Where "d" is dia

Concrete   cover   for   Reinforcement  :-  Footing   -  3" or 75mm Column   -  1.5" or 40mm Beam       -  1.5" or 40mm Slab          -  0.75" or 20mm Stair         -  0.75" or 20 mm Weight   of   steel   in   meter  :- D^2/162.2 kg/m W eight  of   steel   in   feet :- D^2/533 kg/ft Full length of a deformed MS bar is about 40feet or 12 meter TMT :-   Thermo mechanical treated bars TMX :-  Thermax Powered bar SD :-    Super Ductile bar HYSD:- High Yield strength deformed bar CTD :- Cold Twisted bar Basic civil engineering interview questions Civil engineering Interview questions at L&T Type of steel  :- Mild steel - characteristic strength is 250 N/sqmm Hysd - (i) Fe 415 = fy - 415N/sqmm             (ii) Fe500 = fy - 500N/sqmm Minimum number of bars in a square shape column :- 4 no. Minimum number of bars in a Round shape column :- 6 no. For binding one ton of MS bar 8kg to 12 kg binding wire is required. MS bar for chair should not be less than 12mm diamet