Reinforced Cement Concrete Design MCQs 2026

IS 456 applies to

1. A only steel structures ✓
2. B only soil mechanics ✓
3. C only timber roofs ✓
4. D plain and reinforced concrete design ✓

Characteristic compressive strength of concrete fck is defined at

1. A 7 days only ✓
2. B instantaneous load ✓
3. C 28 days cylinder/cube test as per code ✓
4. D 365 days only ✓

Grade M25 concrete means

1. A mean strength 25 after 7 days only ✓
2. B tensile strength 25 ✓
3. C steel yield 25 ✓
4. D characteristic cube strength 25 N/mm² ✓

Partial safety factor for concrete in limit state design (IS 456) is typically

1. A 1.15 only always ✓
2. B 1.0 ✓
3. C 1.5 for strength ✓
4. D 2.0 for serviceability ✓

Partial safety factor for steel reinforcement is typically

1. A 1.5 ✓
2. B 1.0 ✓
3. C 2.0 ✓
4. D 1.15 ✓

Limit state of collapse in RCC deals with

1. A only deflection ✓
2. B only cracking width only ✓
3. C only colour of formwork ✓
4. D strength and stability ✓

Limit state of serviceability includes

1. A deflection and cracking ✓
2. B only ultimate moment capacity ✓
3. C only bond only at ULS ✓
4. D only cover ✓

Balanced section in RCC beam means

1. A only concrete crushes first always ✓
2. B only steel yields with no concrete stress ✓
3. C steel reaches yield simultaneously with concrete reaching ultimate strain ✓
4. D no tension steel ✓

Under-reinforced beam fails by

1. A yielding of steel first ✓
2. B sudden compression crushing without warning ✓
3. C shear only always ✓
4. D bond only ✓

Over-reinforced beam fails by

1. A steel yielding first ✓
2. B pure shear always ✓
3. C deflection only ✓
4. D brittle crushing of concrete ✓

Minimum cover in RCC for durability and bond as per IS 456 depends on

1. A only bar diameter ✓
2. B only span length ✓
3. C only paint colour ✓
4. D exposure condition and member type ✓

Nominal cover for mild exposure to reinforced column may be taken as

1. A 40 mm (typical code value; verify table) ✓
2. B 10 mm always ✓
3. C zero ✓
4. D 200 mm always ✓

Effective depth d of beam is

1. A overall depth minus cover and half bar diameter (main steel) ✓
2. B total depth always ✓
3. C width of beam ✓
4. D span length ✓

Lever arm z in singly reinforced rectangular beam approximates

1. A 0.5d always ✓
2. B 2d ✓
3. C zero ✓
4. D 0.9d or d(1 − 0.42 xu/d) ✓

Maximum strain in concrete at extreme fibre per IS 456 is taken about

1. A 0.0035 in bending ✓
2. B 0.35 ✓
3. C 0.00035 ✓
4. D 0.035 ✓

Modular ratio m for M20 and Fe415 steel (short-term) is approximately

1. A 13.33 using Es/Ec ✓
2. B 1.5 ✓
3. C 100 ✓
4. D 0.5 ✓

Neutral axis depth xu in limit state design from

1. A only shear ✓
2. B force equilibrium C=T ✓
3. C only development length ✓
4. D only cover ✓

Maximum xu/d ratio for Fe415 to avoid over-reinforcement is about

1. A 0.9 ✓
2. B 0.1 ✓
3. C 0.48 ✓
4. D 1.0 ✓

Design tensile stress in steel on limit state is taken as

1. A 0.87 fy ✓
2. B fy only without factor ✓
3. C 0.36 fck ✓
4. D fck ✓

Design compressive block stress in concrete is taken as

1. A 0.87 fy b d ✓
2. B 0.36 fck b xu (rectangular stress block) ✓
3. C fck b d without factor ✓
4. D zero ✓

Doubly reinforced section is used when

1. A only to reduce cover ✓
2. B only for slabs always ✓
3. C only for zero load ✓
4. D moment exceeds limiting moment of singly reinforced section ✓

Compression reinforcement in doubly reinforced beam helps

1. A increase moment capacity and reduce long-term deflection/creep effects ✓
2. B only reduce steel weight always ✓
3. C eliminate shear ✓
4. D remove cover ✓

Shear reinforcement in beams is required when

1. A nominal shear stress exceeds concrete shear capacity ✓
2. B BM is zero ✓
3. C only in slabs ✓
4. D only in columns always ✓

Nominal shear stress τv equals

1. A Mu/(b d) ✓
2. B T/J ✓
3. C Vu/(b d) ✓
4. D P/A only ✓

Bent-up bars provide

1. A only torsion only always ✓
2. B only cover ✓
3. C shear resistance along inclined crack ✓
4. D only bond only ✓

Vertical stirrups resist shear by

1. A aggregate interlock and dowel action plus tension across crack ✓
2. B only bending ✓
3. C only axial compression ✓
4. D only shrinkage ✓

Spacing of shear reinforcement shall not exceed

1. A 0.75d or 300 mm per IS 456 (whichever is less, for beams) ✓
2. B 2d always ✓
3. C 10 mm ✓
4. D span length ✓

Development length ensures

1. A only crack control ✓
2. B only cover ✓
3. C proper transfer of bar force to concrete by bond ✓
4. D only torsion ✓

Development length Ld is proportional to

1. A span only ✓
2. B fy and inversely to bond stress and bar diameter factors ✓
3. C cover only ✓
4. D aggregate colour ✓

Lap splice length is generally

1. A zero ✓
2. B greater of development length and 30φ or code-specified ✓
3. C 5 mm ✓
4. D half span ✓

Hooks and bends in bars improve

1. A anchorage in end regions ✓
2. B only shear in web always ✓
3. C only torsion in slab ✓
4. D only cover reduction ✓

One-way slab is designed as

1. A plate theory always ✓
2. B truss only ✓
3. C steel only ✓
4. D beam of unit width spanning between supports ✓

Two-way slab is used when

1. A only Ly/Lx > 3 ✓
2. B only for bridges steel ✓
3. C loads distribute in both directions (Ly/Lx ≤ 2 often) ✓
4. D only for retaining wall ✓

Minimum steel in RCC slab on grade/hygiene is about

1. A 5% ✓
2. B 0.12% of gross sectional area for HYSD (per IS 456 table) ✓
3. C zero ✓
4. D 50% ✓

Maximum steel in beams per IS 456 is about

1. A 0.4% ✓
2. B 4% of gross area ✓
3. C 40% ✓
4. D no limit ✓

Deflection control in RCC may use

1. A span/depth ratios modified for tension steel ✓
2. B only increase cover ✓
3. C only reduce fck always ✓
4. D ignore creep ✓

Creep in concrete causes

1. A instant elastic deflection only ✓
2. B only increase strength ✓
3. C only reduce cover ✓
4. D increased long-term deflection under sustained load ✓

Shrinkage in concrete leads to

1. A only increased fy ✓
2. B only zero deflection ✓
3. C cracking if restrained ✓
4. D only higher fck instantly ✓

Short column fails primarily by

1. A material crushing (material failure) ✓
2. B elastic buckling always ✓
3. C only shear ✓
4. D only bond ✓

Long column design must consider

1. A only axial capacity without eccentricity ✓
2. B only slab thickness ✓
3. C additional moments due to slenderness (buckling effects) ✓
4. D only bolt grade ✓

Effective length of column in frame depends on

1. A only bar diameter ✓
2. B only w/c ✓
3. C only paint ✓
4. D end restraint coefficients ✓

Minimum eccentricity for column design in IS 456 accounts for

1. A imperfection and minimum moment ✓
2. B zero eccentricity always ✓
3. C only torsion in beam ✓
4. D only slab deflection ✓

Braced column in building frame has

1. A large lateral drift ✓
2. B no vertical load ✓
3. C sidesway prevented by bracing/shear walls ✓
4. D only timber ✓

Unbraced column must be designed for

1. A only axial load without moments ✓
2. B sway moments in addition to gravity ✓
3. C only shear in slab ✓
4. D only development length ✓

Spiral column refers to

1. A circular column with spiral/helical ties for ductile confinement ✓
2. B only rectangular tied ✓
3. C only steel H-section ✓
4. D only timber post ✓

Tied column uses

1. A only spiral always ✓
2. B lateral ties to restrain longitudinal bars ✓
3. C only plain concrete ✓
4. D only bolts ✓

Lateral ties spacing in column shall not exceed

1. A 10 m ✓
2. B zero ✓
3. C least dimension of column or 16φ of longitudinal bar or 300 mm ✓
4. D span of beam ✓

Footing is designed for

1. A only axial steel truss ✓
2. B only wind on roof only ✓
3. C only paint ✓
4. D bearing pressure, bending and shear (one/two-way) ✓

One-way shear in footing checked at

1. A mid-span of column only ✓
2. B section at distance d from column face ✓
3. C soil surface only ✓
4. D top of grade beam only ✓

Two-way punching shear in slab footing checked on

1. A column centre only ✓
2. B far edge of property ✓
3. C only at steel lap ✓
4. D perimeter at d/2 from column face ✓

Cantilever retaining wall stability checks include

1. A only beam deflection ✓
2. B overturning, sliding and bearing pressure ✓
3. C only bolt tension ✓
4. D only truss zero force ✓

Water-cement ratio primarily controls

1. A only bar diameter ✓
2. B only stirrup spacing ✓
3. C strength and durability of concrete ✓
4. D only steel grade ✓

Workability of concrete is measured by

1. A only cube strength ✓
2. B slump test or compaction factor ✓
3. C only yield stress of steel ✓
4. D only cover depth ✓

Nominal mix may be used for concrete up to grade

1. A M60 always ✓
2. B M5 only ✓
3. C any grade without design ✓
4. D M20 for general building as per IS 456 guidance ✓

Design mix concrete is proportioned by

1. A only volume guess ✓
2. B only colour ✓
3. C only aggregate shape only ✓
4. D target mean strength and durability requirements ✓

Target mean strength fck + k·σ accounts for

1. A only steel yield ✓
2. B variability in production ✓
3. C only cover ✓
4. D only lap length ✓

Anchorage beyond bend follows

1. A zero length ✓
2. B full span ✓
3. C only stirrups ✓
4. D code provisions for straight length plus bend contribution ✓

Curtailment of bars in beams follows

1. A random cut points ✓
2. B bending moment diagram envelope and development length beyond cut-off point ✓
3. C mid-support always only ✓
4. D zero anchorage ✓

Bar bending schedule (BBS) provides

1. A only soil bearing ✓
2. B only wind speed ✓
3. C cutting length, shape and number of bars ✓
4. D only bolt torque only ✓

Staggered splices in tension bars avoid

1. A increasing development length to zero ✓
2. B all lap at same section ✓
3. C only compression ✓
4. D concentration of weakness at one section ✓

Torsion in RCC beam requires

1. A only minimum slab steel ✓
2. B longitudinal and transverse reinforcement per IS 456 ✓
3. C no steel ✓
4. D only cover increase only ✓

Equivalent bending moment for combined M and T uses

1. A only ignore torsion ✓
2. B only axial force ✓
3. C Mt equivalent to increase design moment ✓
4. D only shrinkage ✓

Crack width control uses

1. A only ULS steel area ✓
2. B bar spacing and cover limits in SLS ✓
3. C only zero cover ✓
4. D only w/c alone ✓

Fire resistance in RCC improves with

1. A increased cover and member size ✓
2. B reduced cover ✓
3. C zero concrete ✓
4. D only smooth aggregate ✓

Pre-tensioned concrete differs from post-tensioned in that

1. A steel is tensioned before casting concrete in pretensioning ✓
2. B concrete cast first always ✓
3. C no prestress loss ✓
4. D only RCC mild steel ✓

Post-tensioning ducts allow

1. A tendons to be tensioned after concrete hardens ✓
2. B only conventional rebar without jacking ✓
3. C only timber ✓
4. D only soil nails ✓

Loss of prestress includes

1. A only live load ✓
2. B only wind only ✓
3. C only bolt slip ✓
4. D elastic shortening, creep, shrinkage and friction ✓

Shear friction concept uses

1. A only Mohr circle ✓
2. B only Euler buckling ✓
3. C only slump ✓
4. D μ times clamping force across interface ✓

Raft foundation is used when

1. A soil is rock always only ✓
2. B only for steel towers only ✓
3. C only for one column always ✓
4. D individual footings would overlap or bearing is low ✓

Strip footing serves

1. A only isolated column always ✓
2. B only pile cap only ✓
3. C load-bearing wall line ✓
4. D only truss node ✓

Pile foundation transfers load to

1. A only topsoil always ✓
2. B only air gap ✓
3. C deeper competent stratum ✓
4. D only timber deck ✓

Grade beam ties

1. A only slab top ✓
2. B pile heads and supports walls ✓
3. C only roof truss ✓
4. D only bolted steel only ✓

Expansion joint in RCC accommodates

1. A only shear design ✓
2. B thermal/volume changes ✓
3. C only zero movement ✓
4. D only prestress only ✓

Construction joint is

1. A design crack always ✓
2. B planned stop in concreting with proper bond preparation ✓
3. C only rust on steel ✓
4. D only paint line ✓

Honeycombing in concrete is

1. A high strength always ✓
2. B only steel defect ✓
3. C only correct cover ✓
4. D voids due to poor compaction ✓

Segregation in fresh concrete is

1. A uniform mix always ✓
2. B separation of coarse aggregate and mortar ✓
3. C only curing issue only ✓
4. D only formwork oil ✓

Bleeding in concrete is

1. A water rising to surface ✓
2. B steel corrosion only ✓
3. C only form removal time ✓
4. D only bolt tension ✓

Curing of concrete maintains

1. A dry surface always ✓
2. B zero moisture ✓
3. C moisture and temperature for hydration ✓
4. D only vibration during setting only ✓

Modulus of elasticity of concrete Ec per IS 456 is about

1. A fck only ✓
2. B 5000√fck N/mm² ✓
3. C 0.87 fy ✓
4. D Es always ✓

All reinforcement shall be

1. A mild steel only always ✓
2. B without any lap ✓
3. C clearly identifiable grade and free from harmful coatings ✓
4. D without cover ✓

High yield deformed bars improve

1. A bond with concrete due to ribs ✓
2. B only reduce strength ✓
3. C only zero bond ✓
4. D only smooth surface ✓

Splicing of tension bars not allowed in

1. A compression zone always ✓
2. B zero stress zone only always wrong ✓
3. C maximum moment zones unless code exceptions ✓
4. D everywhere freely without rules ✓

Clear cover is measured from

1. A concrete face to nearest bar surface ✓
2. B centre of beam to centre of bar only always ✓
3. C soil level ✓
4. D formwork outside face without concrete ✓

Nominal mix proportion M20 may be approx

1. A 1:10:20 steel ✓
2. B 1:1.5:3 cement:fine:coarse by volume (indicative) ✓
3. C zero cement ✓
4. D only water ✓

Durability exposure class severe requires

1. A higher grade concrete and cover ✓
2. B lower cover always ✓
3. C zero cement ✓
4. D only timber form ✓

Alkali-aggregate reaction causes

1. A only steel yield ✓
2. B only higher fy ✓
3. C expansive cracking in concrete ✓
4. D only zero shrinkage ✓

Sulphate attack on concrete is mitigated by

1. A high w/c always ✓
2. B sulphate-resisting cement and low w/c ✓
3. C zero cover ✓
4. D only smooth bars ✓

Carbonation reduces

1. A concrete strength always increases ✓
2. B only aggregate size ✓
3. C alkalinity leading to steel depassivation ✓
4. D only slump only ✓

Design of staircase waist slab treats it as

1. A only axial column ✓
2. B only truss ✓
3. C only retaining stem without load ✓
4. D simply supported or continuous inclined slab ✓

Flat slab system omits

1. A columns entirely ✓
2. B beams with column supporting slab directly ✓
3. C concrete entirely ✓
4. D all reinforcement ✓