SSC JE Civil cheat sheet

1 bag of cement = 50 kg = 0.0347 m³ of bulk volume; nominal concrete mix 1:2:4 (M15) uses 1 part cement, 2 fine aggregate, 4 coarse aggregate by volume.

Water-cement ratio governs strength and durability: lower w/c gives higher strength; IS 456 limits w/c to 0.45 for severe exposure and 0.40 for very severe/ extreme exposure.

Slump test (IS 1199) is a workability test for concrete: true slump 25-100 mm typical for normal RCC; zero slump = very dry mix, collapse slump = over-wet mix.

Compaction factor test is used for low-workability concrete where slump test is unsuitable; values range 0.70-0.95, higher value means more workable.

Curing: cement concrete must be kept moist for at least 7 days (10 days for OPC-blended or hot weather); strength gain continues with moist curing.

Bulk density of soil: dry unit weight γ_d = γ/(1+w); relative density I_D = (e_max − e)/(e_max − e_min) × 100.

Standard Proctor test gives OMC and MDD; increasing compactive effort lowers OMC and raises MDD.

Bernoulli's equation for ideal fluid: p/γ + v²/2g + z = constant; continuity equation A₁V₁ = A₂V₂ for incompressible flow.

Manning's equation for open channel flow: V = (1/n) R^(2/3) S^(1/2), where R = hydraulic radius = A/P.

Number series: check differences, then ratios, then squares/cubes of consecutive integers, then alternating (two interleaved) series.

Coding-decoding: identify shift pattern (e.g., +2, −3 alternating) or reverse-alphabet position (A=1, Z=26) before applying the rule.

Blood relations: draw a family tree with gender symbols; never assume gender from a name or role word.

Direction sense: use a coordinate grid; net displacement = √(x² + y²), and facing-left/right turns rotate direction by 90° each.

Analogy: determine the relation (part-whole, cause-effect, synonym, worker-tool) and apply the same relation to the answer pair.

Odd-one-out: test each option against a common property (prime, perfect square, divisible by 3, all letters in alphabet position) until only one fails.

Syllogism: a conclusion is valid only if it holds in every possible Venn diagram of the premises; 'some' does not imply 'all'.

Mirror image: left-right reverses, up-down stays; water image: up-down reverses, left-right stays.

Seating arrangement: fix the most constrained person first, then place others relative to fixed positions; circular facing-centre means left = clockwise.

Fundamental Rights are in Part III (Articles 12-35); Right to Constitutional Remedies (Art. 32) was called the 'heart and soul' of the Constitution by Dr. B. R. Ambedkar.

Directive Principles of State Policy are in Part IV (Articles 36-51), non-justiciable; Fundamental Duties in Part IVA (Article 51A), added by the 42nd Amendment.

Indian Standard Meridian is 82°30′ E, passing near Mirzapur (Uttar Pradesh); IST = UTC + 5:30.

Tropic of Cancer (23°26′ N) passes through 8 Indian states, including Gujarat, Rajasthan, Madhya Pradesh, Chhattisgarh, Jharkhand, West Bengal, Tripura, and Mizoram.

Rivers: Ganga rises from Gangotri (Bhagirathi), Brahmaputra from Chemayungdung; Godavari is the longest peninsular river, called 'Dakshin Ganga'.

First in India: first Governor-General of independent India - Lord Mountbatten; first President - Dr. Rajendra Prasad; first woman IPS officer - Kiran Bedi.

Physics: SI unit of force is newton (N); work - joule (J); power - watt (W); pressure - pascal (Pa); frequency - hertz (Hz).

Chemistry: pH < 7 acidic, = 7 neutral, > 7 basic; litmus turns red in acid; common salt is NaCl, baking soda NaHCO₃, washing soda Na₂CO₃·10H₂O.

Biology: human body has 206 bones in adults, 12 pairs of cranial nerves, and blood pH is tightly maintained near 7.4.

Limit state method: design strength = 0.87 f_y for steel; partial safety factors γ_f for loads and γ_m = 1.15 for concrete, 1.15 for steel in limit state of collapse.

For a simply supported beam of span L under UDL w: M_max = wL²/8 at midspan, V_max = wL/2 at supports, deflection δ = 5wL⁴/(384EI).

For a cantilever of length L with point load P at free end: M_max = PL at fixed end, δ_max = PL³/(3EI).

Section modulus Z = I/y_max; bending stress σ = M/Z; for a rectangle b×d, Z = bd²/6; for a circle of diameter d, Z = πd³/32.

Euler buckling load for a column: P_cr = π²EI/L_eff²; effective length depends on end conditions (both pinned L, fixed-fixed 0.5L, fixed-free 2L).

Shear force diagram slope equals load intensity; bending moment diagram slope equals shear force; M is maximum where SF is zero.

Stress-strain: Young's modulus E = σ/ε; Poisson's ratio μ = lateral strain/longitudinal strain (≈0.3 for steel, 0.15-0.2 for concrete).

Torsion of circular shaft: τ_max = T·r/J, angle of twist θ = TL/(GJ); for solid circular shaft J = πd⁴/32.

IS 456 minimum reinforcement: 0.12% of gross area for Fe415 HYSD in slabs, 0.15% for mild steel; minimum cover depends on exposure (20 mm mild, 30-45 mm severe).