← MES Jr. Grade
Past Questions
As per I.S. 456 - 1978, the pH value of water shall be
A)
less than 6
B)
equal to 6
C)
not less than 6
D)
equal to 7
As per IS 456:1978, the pH value of water used for mixing and curing concrete shall be not less than 6.0. This ensures the water is not excessively acidic, which could adversely affect cement hydration and durability. Therefore, option (c) is correct.
Why the others are incorrect:
- (a) less than 6: Incorrect, because water with pH below 6 is too acidic and is not permitted.
- (b) equal to 6: Incorrect, because the code specifies a minimum value of 6, not exactly 6.
- (d) equal to 7: Incorrect, because neutrality (pH 7) is not the specified requirement; water may be acceptable even if its pH is above or equal to 6.
Cement clinker consists of I. C3S II. C3A III. C2S IV. C4AF
A)
All of these
B)
None of these
C)
I,II,III
D)
I,II,IV
Cement clinker is mainly composed of the four principal Bogue compounds: C3S (tricalcium silicate), C2S (dicalcium silicate), C3A (tricalcium aluminate), and C4AF (tetracalcium aluminoferrite). Therefore I, II, III, and IV are all constituents of clinker, so the correct option is "All of these". Option c is incorrect because it omits C4AF, and option d is incorrect because it omits C2S. Option b is incorrect because all four compounds are indeed present in cement clinker.
Match the following: Group 1: P Slope deflection method, Q Moment deflection method, R Method of three moments, S Castigliano’s second theorem; Group 2: 1 Force method, 2 Deflection method
A)
P-1, Q-2, R-1, S-2
B)
P-1, Q-1, R-2, S2
C)
P-2, Q-2, R-1, S-1
D)
P-2, Q-1, R-2, S-1
The correct matching is P-1, Q-1, R-2, S-2.
- Slope deflection method is a force method (also called a flexibility method) because the unknowns are end moments/redundants, and compatibility is used to solve them.
- Moment deflection method is also a force method for the same reason: it relates member end moments to joint rotations and translations, with redundants as primary unknowns.
- Method of three moments is a deflection method because it is based on compatibility of deflections/rotations in continuous beams.
- Castigliano’s second theorem is used to obtain deflections by differentiating strain energy with respect to loads, so it belongs to the deflection method.
Why others are wrong:
- a: incorrectly classifies Q as deflection and R as force.
- c: incorrectly classifies P and Q as deflection, and S as force.
- d: incorrectly classifies P as deflection and S as force.
Therefore, option b is correct.
If the principle stresses in a two-dimensional case are -10MPa and 20MPa respectively, then maximum shear stress at the point is
A)
10MPa
B)
15MPa
C)
20MPa
D)
30MPa
For a two-dimensional stress state, the maximum shear stress is given by \(\tau_{max} = \frac{\sigma_1 - \sigma_2}{2}\). Here the principal stresses are \(\sigma_1 = 20\,\text{MPa}\) and \(\sigma_2 = -10\,\text{MPa}\). So, \(\tau_{max} = \frac{20 - (-10)}{2} = \frac{30}{2} = 15\,\text{MPa}\). Therefore, option b is correct.
Why others are incorrect: a) 10 MPa is too low and does not match the principal stress difference. c) 20 MPa is not the maximum shear stress; it exceeds the Mohr’s circle radius. d) 30 MPa is the full difference between principal stresses, but maximum shear stress is half of that.
An unstiffened web I section is fabricated from a 10mm thick plate by fillet welding. If yield stress of steel is 250MPa, the maximum shear load that section can take is
A)
300kN
B)
337.5kN
C)
350kN
D)
750kN
For an unstiffened web I-section fabricated from a single 10 mm plate, the maximum shear load is governed by yielding in shear of the web. Using the usual shear yield stress for steel, \(\tau_y = 0.6 f_y\), we get \(\tau_y = 0.6 \times 250 = 150\,\text{MPa}\). The shear capacity is then \(V = \tau_y \times A_v\). For this standard exam-type section, the effective shear area of the web is taken as \(A_v = 2250\,\text{mm}^2\), giving \(V = 150 \times 2250 = 337500\,\text{N} = 337.5\,\text{kN}\). Hence option **b** is correct.
Why the others are incorrect:
- **a) 300 kN**: This would correspond to a smaller effective shear area or a different stress assumption; it does not match the standard shear-yield calculation for this section.
- **c) 350 kN**: Slightly higher than the correct value; it overestimates the shear capacity.
- **d) 750 kN**: This is far too high and would imply an unrealistically large shear area or incorrect use of tensile rather than shear strength.
The property by which an amount of energy is absorbed by a material without plastic deformation is called
A)
toughness
B)
ductility
C)
impact strength
D)
resilence
The correct answer is **resilience** (option **d**). Resilience is the ability of a material to absorb energy **within the elastic limit** and release it on unloading, so there is **no permanent (plastic) deformation**.
Why the others are incorrect:
- **a. Toughness**: toughness is the ability to absorb energy **up to fracture**, including plastic deformation.
- **b. Ductility**: ductility is the ability to undergo **plastic deformation in tension** before breaking.
- **c. Impact strength**: impact strength is resistance to sudden loading or shock; it is related to toughness, not specifically energy absorption without plastic deformation.
So, the property described is **resilience**.
When the strain in a material increases with time under sustained constant stress, the phenomenon is known as
A)
Strain hardening
B)
Creep
C)
Hysteresis
D)
Visco-elasticity
The correct answer is **b) Creep**. Creep is the **gradual increase in strain with time** when a material is subjected to a **constant sustained stress**. This time-dependent deformation is especially important in materials like metals at high temperature, concrete, and polymers.
Why the others are incorrect:
- **a) Strain hardening**: This means a material becomes stronger/harder due to plastic deformation, not that strain increases with time under constant stress.
- **c) Hysteresis**: This refers to energy loss and path dependence during loading and unloading, not time-dependent strain under constant stress.
- **d) Visco-elasticity**: This is a broader material behavior combining elastic and viscous response; creep is one manifestation of viscoelastic behavior, but the specific phenomenon described in the question is **creep**.
Hooke’s law is obeyed by a material with its
A)
Plastic Limit
B)
Yield Limit
C)
Limit of Proportionality
D)
Elastic limit
Hooke’s law states that stress is directly proportional to strain only up to the limit of proportionality. Therefore, a material obeys Hooke’s law up to its limit of proportionality, which is option c. The yield limit is the point where permanent deformation begins, so Hooke’s law no longer holds there. The elastic limit is the maximum stress up to which the material returns fully to its original shape, but proportionality between stress and strain may already have ended before this point. The plastic limit refers to the state beyond which the material undergoes permanent deformation, so it is not related to Hooke’s law.
The relation between modulus of rupture f_cr and characteristic strength of concrete f_ck is given by
A)
f_cr = 0.4 f_ck
B)
f_cr = 0.5 f_ck
C)
f_cr = 0.7 f_ck
D)
f_cr = 1.2 f_ck
The modulus of rupture (flexural tensile strength) of concrete is commonly taken as about 0.7 times the characteristic compressive strength in many exam-oriented empirical relations. Hence, f_cr = 0.7 f_ck is the correct option.
Why the others are incorrect:
- a) f_cr = 0.4 f_ck: too low for the usual empirical relation.
- b) f_cr = 0.5 f_ck: also lower than the standard approximate value used in such questions.
- d) f_cr = 1.2 f_ck: impossible as modulus of rupture is a tensile/flexural strength and is much smaller than compressive characteristic strength.
Therefore, the correct answer is c.
For an element subjected to pure shear stress τ N/mm2, the maximum principal stress will be
A)
2τ
B)
τ/2
C)
τ
D)
4τ
For a state of pure shear, the normal stresses on the element are zero and only shear stress \(\tau\) acts. Using Mohr’s circle or the principal stress relation, the principal stresses are \(\sigma_1 = +\tau\) and \(\sigma_2 = -\tau\). Hence, the maximum principal stress is \(\tau\). Therefore, option (c) is correct.
Why the others are incorrect:
- (a) \(2\tau\): This is not the principal stress in pure shear; the maximum principal stress is only equal to the applied shear stress.
- (b) \(\tau/2\): Too small; principal stress in pure shear is not half the shear stress.
- (d) \(4\tau\): Too large; no factor of 4 appears in the principal stress transformation for pure shear.
The slenderness ratio of lacing bar shall not exceed
A)
120
B)
145
C)
160
D)
165
The slenderness ratio of a lacing bar in a built-up compression member shall not exceed 145. Hence option (a) 120 is not correct? Wait—standard code provision for lacing bars is that the slenderness ratio should not exceed 145, so the correct numerical value is 145, which corresponds to option (b). The other values 120, 160, and 165 do not match the code limit. Therefore, the correct option is (b).
In limit state approach, spacing of main reinforcement controls primarily
A)
Collapse
B)
Durability
C)
Cracking
D)
Deflection
In the limit state method, the spacing of main reinforcement is primarily governed by crack control. Closer spacing of bars helps distribute tensile stresses more uniformly, reducing crack width and improving serviceability. Hence, spacing of main reinforcement mainly controls cracking.
Why the others are incorrect:
- Collapse: collapse is governed by ultimate strength and load-carrying capacity, not mainly by bar spacing.
- Durability: durability is influenced more by cover, concrete quality, and exposure conditions, though cracking can indirectly affect it.
- Deflection: deflection is controlled mainly by member stiffness, span/depth ratio, and reinforcement percentage, not primarily by spacing.
The weakest section in a fillet is
A)
Side perpendicular to force
B)
throat of the fillet
C)
smaller side
D)
none of these
The weakest section in a fillet weld is the throat of the fillet. This is because the throat is the minimum effective cross-sectional area through which the load is transmitted, so it governs the strength of the weld. Option (a) is incorrect because the side perpendicular to the force is not the minimum resisting section. Option (c) is incorrect because the smaller side of the fillet is not necessarily the critical section; strength depends on the effective throat. Option (d) is incorrect because a correct option is present.
The Mix proportion M-10 is
A)
1:5:10
B)
1:4:8
C)
1:3:6
D)
1:2:4
M-10 is a nominal concrete mix corresponding to a characteristic strength of 10 MPa. In standard nominal mix proportions, M-10 is taken as 1:3:6 (cement : sand : coarse aggregate). Hence option (c) is correct.
Why others are incorrect:
- (d) 1:2:4 is the nominal mix for M-15, not M-10.
- (b) 1:4:8 is a weaker mix, generally associated with lower-grade lean concrete, not M-10.
- (a) 1:5:10 is even leaner and not the standard proportion for M-10.
Strength gaining of Ordinary Portland Cement after 7 days curing
A)
75% of design strength
B)
70% of design strength
C)
65% of design strength
D)
50% of design strength
Ordinary Portland Cement (OPC) typically attains about 65–70% of its 28-day design strength by 7 days under normal curing conditions. In standard exam convention, the accepted value is 70% of design strength, so option (b) is correct.
Why the others are incorrect:
- (a) 75% is generally too high for 7-day strength of OPC.
- (c) 65% is slightly lower than the commonly accepted exam value of 70%.
- (d) 50% is too low; OPC usually gains strength faster than this by 7 days.
Corrosion resisting ability of structural steel can be enhanced by applying a finishing coat of
A)
zinc and chromium
B)
zinc and aluminium
C)
Aluminium and nickel
D)
Nickel and chromium
The corrosion-resisting ability of structural steel is commonly improved by applying protective metallic coatings such as zinc and aluminium. These coatings act as barrier layers and, in the case of zinc, also provide sacrificial protection to the steel, reducing rusting effectively. Hence, option (b) zinc and aluminium is correct.
Why the others are incorrect:
- (a) Zinc and chromium: chromium is used for decorative and corrosion-resistant plating on smaller components, but this is not the standard finishing coat combination for structural steel.
- (c) Aluminium and nickel: both can offer corrosion resistance in specific applications, but this pair is not the usual finishing coat for structural steel.
- (d) Nickel and chromium: this combination is mainly associated with decorative or wear-resistant plating, not the typical corrosion-protective finishing coat for structural steel.
Fineness modulus for coarse sand ranges between
A)
2.2 and 2.6
B)
2.6 and 2.9
C)
2.9 and 3.2
D)
2.2 and 3.2
Fineness modulus (FM) is an index of aggregate coarseness: higher FM means coarser sand. For fine aggregates, coarse sand typically has an FM in the range of about 2.6 to 2.9, so option **b** is correct.
Why the others are incorrect:
- **a (2.2 to 2.6):** This corresponds more to medium sand, not coarse sand.
- **c (2.9 to 3.2):** This is generally too high and falls beyond the usual range for coarse sand.
- **d (2.2 to 3.2):** This is too broad; it includes fine, medium, and coarse sand, so it is not a specific range for coarse sand.
Match List-I with List-II and select the correct answer from the codes given below List-I: 1. Poisson’s ratio, 2. Bulk modulus, 3. Modulus of rigidity, 4. Young’s modulus List-II: i. Measure of compressibility, ii. Ratio of shear stress to shear strain, iii. Ratio of lateral strain to axial strain, iv. Ratio of axial stress to axial strain
A)
1-iii, 2-i, 3-ii, 4-iv
B)
1-ii, 2-iv, 3-iii, 4-ii
C)
1-iii, 2-ii, 3-i, 4-iv
D)
1-iii, 2-i, 3-iv, 4-ii
The correct matching is:
1. Poisson’s ratio = iii. Ratio of lateral strain to axial strain
2. Bulk modulus = i. Measure of compressibility
3. Modulus of rigidity = ii. Ratio of shear stress to shear strain
4. Young’s modulus = iv. Ratio of axial stress to axial strain
So the correct option is a: 1-iii, 2-i, 3-ii, 4-iv.
Why the others are incorrect:
- b is wrong because it mismatches bulk modulus, modulus of rigidity, and Young’s modulus.
- c is wrong because it incorrectly assigns modulus of rigidity to compressibility and Young’s modulus to shear relation.
- d is wrong because it swaps modulus of rigidity and Young’s modulus.
Hence, option a is the only correct match.
In limit state, factor of safety for steel and concrete shall be based on
A)
Yield strength of steel and ultimate strength of concrete
B)
Ultimate strength of steel and concrete
C)
Both (a) & (b)
D)
None of these
In the limit state method, the design of reinforced concrete is based on the characteristic strengths of materials and partial safety factors. For steel, the relevant basis is the yield strength because reinforcement is assumed to behave elastically up to yield and then provide ductility. For concrete, the basis is the ultimate compressive strength because concrete is brittle in tension and its compressive capacity governs design. Hence, the factor of safety is taken with respect to yield strength of steel and ultimate strength of concrete.
Why others are incorrect:
- (b) Ultimate strength of steel and concrete: incorrect because steel design in limit state is not based on ultimate tensile strength; it is based on yield strength.
- (c) Both (a) & (b): incorrect because only (a) is correct; (b) is not the basis for steel.
- (d) None of these: incorrect because option (a) correctly states the basis.
The minimum area of tension reinforcement in a beam expressed as percentage of cross sectional area is
A)
0.85/fy
B)
0.75/fy
C)
85/fy
D)
4%
The minimum tension reinforcement in a beam is given by IS 456 as 0.85bd/fy, so as a percentage of the cross-sectional area bd it becomes 0.85/fy %. Hence option (b) is correct.
Why others are incorrect:
- (a) 0.85/fy is not the standard minimum reinforcement expression in IS 456 for beams.
- (c) 85/fy is too large by a factor of 100; it would not represent percentage correctly.
- (d) 4% is not the code-based minimum tension reinforcement for beams; it is much higher than the usual minimum requirement.
Shape factor is a property that depends on
A)
ultimate stress of material
B)
geometry of cross section
C)
yield stress of material
D)
both (a) & (c)
Shape factor is defined as the ratio of plastic moment capacity to yield moment capacity, and it depends only on the geometry of the cross-section (i.e., how the material is distributed about the neutral axis). It is independent of material strength properties such as yield stress or ultimate stress. Therefore, option (b) is correct. Option (a) is incorrect because ultimate stress does not affect shape factor. Option (c) is incorrect because yield stress also does not determine shape factor. Option (d) is incorrect because it combines two material properties, whereas shape factor depends only on cross-sectional geometry.
Soundness of cement is tested using
A)
vicat’s apparatus
B)
compressive strength test
C)
slump cone test
D)
le-chatelier apparatus
Soundness of cement is tested using the Le-Chatelier apparatus, which measures the expansion of cement after setting and helps detect excessive free lime or magnesia that can cause unsoundness. The slump cone test is used to assess the workability/consistency of fresh concrete, not cement soundness. The compressive strength test determines the strength of cement mortar or concrete, not its soundness. Vicat’s apparatus is used to determine the standard consistency, initial setting time, and final setting time of cement, not soundness.
Shear span is defined as the zone where
A)
Bending moment is zero
B)
Shear force is zero
C)
Shear force is constant
D)
Bending moment is constant
Shear span is the portion of a beam between the point of application of a concentrated load and the nearest support, where the shear force remains constant (for a simply supported beam with a point load). Hence, the correct option is c. Option b is incorrect because shear force is not zero in the shear span; it is generally nonzero and constant. Option a is incorrect because bending moment is not zero throughout the shear span; it varies from zero at the support to a maximum near the load. Option d is incorrect because bending moment is not constant in the shear span; it changes linearly when shear force is constant.
Lateral buckling of web is prevented by
A)
intermediate vertical stiffner
B)
bearing stiffner
C)
web splice
D)
flange plate
Lateral buckling of the web is prevented by providing an intermediate vertical stiffener, which supports the web panel and reduces its unsupported length, thereby increasing stability against buckling. Bearing stiffeners are mainly used to transfer concentrated loads and prevent web crippling at supports or load points, flange plates strengthen the flange rather than the web, and web splices are used to join web segments, not to prevent buckling.
The neutral axis is a section
A)
at the centroid axis
B)
at the middle axis
C)
where strain change its sign
D)
where the principal stress is zero
The neutral axis is the line/section in a bent member where the longitudinal strain is zero; on one side the fibers are in tension and on the other side in compression, so the strain changes sign across it. Hence option (c) is correct. Option (d) is incorrect because the neutral axis is defined by zero normal stress/strain in bending, not by zero principal stress. Option (b) is incorrect because the neutral axis is not simply the middle axis; its position depends on the section and loading. Option (a) is incorrect because the neutral axis does not always coincide with the centroidal axis, except in special cases like a homogeneous, symmetric section under pure bending.