BT-204 Basic Civil Engineering & Mechanics - Dec 2025 Question Paper

Under each question, How to answer lists the points an answer should cover, outlined by CampusPrep from the syllabus. Check the details against your textbook.

1. 7 Marks
   aExplain various methods of compaction of concrete and their importance.
   How to answer

   • Define compaction and its purpose - removal of air voids, strength and durability.
   • Explain methods: hand compaction - tamping, rodding; mechanical - internal, external, surface and table vibrators.
   • Explain importance: density, bond, permeability, honeycombing prevention.
2. 7 Marks
   bDescribe different types of staircases with neat sketch and explain their suitability for different buildings.
   How to answer

   • List types: straight, dog-legged, open-well, spiral, quarter-turn, three-quarter turn.
   • Provide neat labelled sketches of each type.
   • Explain suitability for residential, public, commercial buildings based on space and traffic.
3. 7 Marks
   aExplain the different methods of measuring elevations, including spirit leveling, trigonometric leveling and barometric leveling.
   How to answer

   • Define elevation / levelling and its object.
   • Explain spirit levelling - principle, instrument and staff.
   • Explain trigonometric levelling and barometric levelling with formulas and limitations.
4. 7 Marks
   bWhat are electronic surveying instruments? Explain their need and advantages over conventional instruments.
   How to answer

   • Define electronic surveying instruments - EDM, total station, GPS, digital level.
   • Explain need for speed, accuracy and automation.
   • Compare advantages over conventional chain, compass and dumpy level.
5. 7 Marks
   aDescribe the steps involved in preparing a profile and cross-section for a proposed road project.
   How to answer

   • State purpose of profile and cross-section levelling for road alignment.
   • Steps: reconnaissance, chainage marking, level observation, plotting profile.
   • Plotting cross-sections at intervals for earthwork calculation.
6. 7 Marks
   bDefine contour. Explain the characteristics of contour lines and their significance in engineering projects.
   How to answer

   • Define contour as line joining points of equal elevation.
   • Explain characteristics: never intersect, uniform spacing, closed loops, perpendicular to steepest slope.
   • Explain significance in route location, earthwork, drainage and reservoir capacity.
7. 7 Marks
   aExplain the procedure to find forces in members of truss by using method of sections.
   How to answer

   • State principle: cut truss by section cutting max three members.
   • Steps: find reactions, draw free body, apply equilibrium equations.
   • Determine tensile/compressive nature of forces.
8. 7 Marks
   bTwo forces, one of which is double the other has resultant of 260 N. If the direction of the larger force is reversed and the other remains unaltered, the resultant reduces to 180 N. Determine the magnitude of the force and the angle between the forces.
   How to answer

   • Let smaller force $F$, larger $2F$ with angle $\theta$; apply $R^2 = F_1^2+F_2^2+2F_1F_2\cos\theta$.
   • Form two equations for $R=260\,\text{N}$ and $R'=180\,\text{N}$ after reversal.
   • Solve for $F$ and $\theta$.
9. 7 Marks
   aDetermine the centre of gravity of solid cone of base Radius 'R' and height 'h'.
   How to answer

   • Consider solid cone of radius $R$, height $h$ with elemental disc.
   • Integrate volume moments about base/apex using $dV = \pi r^2 dy$.
   • Show $\bar{y}=h/4$ from base or $3h/4$ from apex on axis of symmetry.
10. 7 Marks
    bDefine centroid and centre of gravity. Explain the difference between them with suitable examples.
    How to answer

    • Define centroid as geometric centre and centre of gravity as weight resultant point.
    • Differentiate: area/volume vs weight, uniform vs non-uniform gravity.
    • Give examples: uniform lamina vs composite body.
11. 7 Marks
    aExplain various laboratory tests on concrete and mortar with neat sketches.
    How to answer

    • List tests: slump, compaction factor, compressive, split-tensile for concrete; consistency, setting, mortar strength.
    • Explain procedure of each with neat sketches of apparatus.
    • State relevance to workability and strength.
12. 7 Marks
    bCalculate the reactions in cantilever beam shown below.

    How to answer

    • Draw free body with fixed-end reactions $A_x, A_y, M_A$.
    • Apply $\sum F_x=0$, $\sum F_y=0$, $\sum M=0$ including UDL $1\,\text{kN/m}\times 3\,\text{m}$ and $6\,\text{kN}$ and $8\,\text{kN.m}$.
    • Compute vertical reaction, moment at wall; horizontal reaction zero.
13. 7 Marks
    aDetermine the forces in the truss shown in Fig. It carries a horizontal load of 16 kN and vertical load of 24 kN.

    How to answer

    • Find reactions at pin A and roller B for 16 kN horizontal and 24 kN vertical loads.
    • Use method of joints/sections at A, B, C, D.
    • Report magnitude and tensile/compressive nature for AC, BC, CD, AB.
14. 7 Marks
    bDefine remote sensing. Describe the components of a remote sensing system with neat sketches.
    How to answer

    • Define remote sensing as acquisition of data without physical contact.
    • Describe components: energy source, sensor, platform, transmission, processing.
    • Provide neat sketch of system showing sun, satellite, ground station.
15. 7 Marks
    aExplain the conventional methods of distance measurement using chains and tapes.
    How to answer

    • Define chaining and taping instruments - chain, tape, arrows, ranging rods.
    • Explain procedures: ranging, chaining, offsetting, error corrections.
    • Mention precision and field precautions.
16. 7 Marks
    bDescribe the manufacturing process of bricks. Explain the properties of good building bricks and laboratory tests conducted on bricks.
    How to answer

    • Describe brick manufacture: preparation, moulding, drying, burning in kiln.
    • Explain properties of good bricks: strength, water absorption, soundness, shape.
    • List lab tests: compressive strength, water absorption, efflorescence, soundness.