Activated sludge process: F/M ratio, MLSS, SRT and SVI
How the most common sewage treatment process works, and the four numbers operators watch every day.
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Atterberg limits and plasticity index in plain words
Liquid limit, plastic limit and shrinkage limit, what the plasticity index tells you, and how the A-line classifies fine soils.
Bernoulli's equation and the venturimeter
Energy along a streamline as pressure head, velocity head and datum head, and how a venturimeter turns a pressure drop into a flow rate.
Bitumen tests and VG grades, explained for exams and site
Penetration, softening point, ductility and viscosity tests, and how India moved to VG-10, VG-30 and VG-40 grading.
BOD: what it measures and how to calculate it
Biochemical oxygen demand, the first-order BOD curve, the dilution test, and the effect of temperature on the rate constant.
Curvature and refraction corrections in levelling
Why long sights read too high, the 0.0785 d² and 0.0112 d² corrections, and the distance to the visible horizon.
Darcy's law and how permeability is measured
Flow of water through soil, the coefficient of permeability, and when to use the constant head or falling head test.
Flexible pavement layers and the CBR test
What each layer of a bituminous road does, how the CBR test works, and how IRC:37 uses traffic in msa and subgrade CBR.
The hydraulic jump: sequent depths and energy loss
How supercritical flow suddenly turns subcritical, how to find the depth after the jump, and why jumps are used to protect spillways.
BPBCC Patna hiring 18 Junior Engineers (Civil) on contract, last date 25 Nov
Bihar Police Building Construction Corporation needs diploma civil engineers with two years of building experience, at ₹40,000 a month.
UT Chandigarh: 4 Executive Engineer (Civil) posts on deputation, last date 24 Nov
For serving government civil engineers with 10 years' experience. Level 11 pay, apply through proper channel.
Deendayal Port Authority: Deputy Chief Engineer (Civil), apply by 27 Nov
Absorption post for civil engineers already serving in Major Port Authorities, pay ₹80,000 – ₹2,20,000.
JKSSB Junior Engineer (Civil) 2026: 458 posts, apply 30 Nov – 29 Dec
Jammu and Kashmir SSB has advertised 458 JE Civil posts in Jal Shakti and PWD (R&B) at Pay Level 6. Applications open on 30 November 2026.
KEA Junior Engineer 2026: civil posts in GBA, BBMP, KHB and KRIDL, last date 26 Nov
Karnataka Examinations Authority is recruiting 97 Junior Engineers, most of them civil. Apply online by 26 November 2026.
Levelling: height of instrument vs rise and fall, with the checks
How to reduce a level book both ways, the arithmetic checks examiners love, and when each method is better.
Limit state design in IS 456: partial safety factors made simple
What limit states are, why loads go up and strengths come down, and where 0.446 fck and 0.87 fy come from.
Manning's equation for uniform flow in open channels
How slope, roughness and channel shape set the velocity in a canal or drain, with typical n values and a worked trapezoidal example.
Two India-funded bridges open on Bhutan's Trashigang highway
The Revidrang and Rolong bridges replace weak, cracked old bridges and were built for Nu. 76 million under Indian project-tied assistance.
Nandyal–Gazulapalli section of Guntur–Guntakal doubling commissioned
South Coast Railway opened 15.121 km of new double line for 100 km/h after the CRS inspection; the tunnel section is next.
Eight bidders chase NHAI's 90.6 km NH-27 toll-operate-transfer bundle
The Purnea–Dalkhola–Raiganj stretch is NHAI's TOT Bundle 22; the winner gets 20 years of toll rights for an upfront payment.
Centre approves 8.45 km Noida Sector 51 – Greater Noida West metro line
The Union Government approved a ₹2,390 crore elevated metro line with five stations, to be built by NMRC within four years.
New Vaitarna rail bridge finished as Virar–Dahanu quadrupling moves ahead
The South Vaitarna bridge on Mumbai's western corridor is complete and its northern twin is almost ready, doubling track capacity over the river.
One-way and two-way slabs: how to tell them apart and design them
The long span to short span rule, minimum steel, maximum bar spacing and span/depth ratios for RCC slabs to IS 456.
Head loss in pipes: Reynolds number and Darcy–Weisbach
Laminar or turbulent, how to get the friction factor, and how to work out the head lost in a water main.
Population forecasting for water supply design
Arithmetic, geometric and incremental increase methods with a worked example, and how per capita demand turns population into flow.
RCC columns: short or long, minimum eccentricity and axial capacity
How IS 456 classifies columns, the minimum eccentricity rule, and the formula for the axial load capacity of a short column.
Settling tanks: Stokes' law and surface overflow rate
How fast particles settle, why tank depth doesn't decide removal, and how to size a sedimentation tank.
Shear strength of soil and the Mohr–Coulomb equation
What cohesion and friction angle mean, why effective stress controls strength, and which shear test to pick.
Simple circular curves: elements and setting out by Rankine's method
Tangent length, curve length, external distance and long chord, and how deflection angles set out the curve with a theodolite.
Singly reinforced RCC beam: neutral axis and limiting moment
How to find the neutral axis depth, why IS 456 caps it, and how to design the steel for a given moment.
Soil compaction: Proctor test, OMC and maximum dry density
Why there is a best water content for compaction, how the compaction curve is drawn, and what the zero air voids line means.
Soil phase relations: void ratio, porosity, water content and unit weight
The three-phase soil diagram and the handful of relations, like Se = wG, that solve almost every phase problem.
Bending stress and the flexure formula, explained
Why beams carry the highest stress at the top and bottom fibres, and how M/I = σ/y = E/R lets you calculate it.
Column buckling: Euler's formula and effective length
Why slender columns fail by bending sideways long before they crush, and how end conditions change the buckling load.
Stress, strain and Hooke's law: the starting point of SOM
What stress and strain really mean, how Young's modulus links them, and how to find the elongation of a loaded bar.
Thin cylinders under pressure: hoop and longitudinal stress
Why pipes and tanks split along their length, and how to find the wall thickness of a pressure vessel.
Torsion of circular shafts: T/J = τ/r = Gθ/L
How twisting moment creates shear stress in a shaft, why hollow shafts are efficient, and how to size a shaft for power.
Specific energy, critical depth and the Froude number
Why one discharge can flow at two depths, what critical flow is, and how the Froude number separates subcritical from supercritical flow.
Steel tension members to IS 800: yielding, rupture and block shear
The three ways a bolted tension member can fail, with the IS 800:2007 formulas and a worked angle-section example.
Stopping sight distance: how far ahead a driver must see
Reaction distance plus braking distance, the IRC values for reaction time and friction, and the effect of gradient.
Superelevation on horizontal curves, with the IRC method
Why roads are banked on curves, the e + f = V²/127R relation, IRC limits, and a step-by-step design.
Tacheometry: measuring distance with stadia hairs
How a theodolite with stadia hairs gives horizontal distance and elevation from a single staff reading, including inclined sights.
Traffic flow fundamentals: speed, flow and density
The relation q = k v, Greenshields' linear model, and how to find the capacity of a road lane.
Closed traverse: latitudes, departures and Bowditch's rule
How to compute a traverse, find the closing error, and adjust it with the compass (Bowditch) rule.
How a water treatment plant works, unit by unit
From intake to tap: screening, aeration, coagulation, flocculation, sedimentation, filtration and disinfection.