Question 1

Daylighting through roofs: The window-like opening provided in the flat roof of a room for admitting light (and often ventilation) is called a

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Introduction / Context: Rooms with deep plans or without external walls often rely on roof openings for daylight and, sometimes, ventilation. Different roof-lighting devices have specific names based on their form and placement. Given Data / Assumptions: The roof is flat (or near-flat) and includes a glazed opening. Objective is to supply daylight from above. Terminology distinguishes skylights, lanterns, dormers, louvers, and clerestories. Concept / Approach: A “skylight” (roof window) is a glazed opening set into a roof plane to admit light directly from the sky. A “lantern window” (roof lantern) is a raised glazed structure with vertical sides, more architectural and often used over halls or stairwells. “Dormer windows” are vertical windows projecting from pitched roofs, primarily in attics, not in flat roofs. “Louvered windows” regulate airflow rather than admit ample light; “clerestory” is a high wall window below the roof edge, not a roof opening. Step-by-Step Solution: Identify placement: in the flat roof fabric itself.Select the generic term for such a roof opening → “skylight.”Differentiate from lantern (raised glazed structure) and dormer (in sloping roofs).Choose “Skylight (roof window).” Verification / Alternative check: Architectural standards refer to flat-roof rooflights as skylights; roof lanterns are a subtype with a raised ridge and glazed sides. Why Other Options Are Wrong: Dormer: needs pitched roof and vertical face.Lantern: different configuration; not the generic flat roof opening.Louvered: airflow control, not primarily daylighting.Clerestory: high wall windows, not in the roof plane. Common Pitfalls: Confusing lanterns with skylights; neglecting waterproofing and fall toward gutters around skylights. Final Answer: Skylight (roof window).

Question 2

Pile capacity terminology: Which statements are correct regarding bearing capacity and safety factors for piles?

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Introduction / Context: Pile foundations are designed using ultimate capacity, settlement criteria, and appropriate factors of safety. It is important to distinguish definitions of working (safe) load, ultimate load, and the factor of safety typically adopted in practice. Given Data / Assumptions: (a) Bearing capacity of a pile: load sustainable without excessive settlement. (b) Ultimate bearing capacity: maximum load beyond which the pile continues to sink without additional load increase. (c) Safe bearing capacity: ultimate capacity divided by factor of safety. (d) Factor of safety taken as 6 (claim to be evaluated). Concept / Approach: Statements (a), (b), and (c) reflect standard definitions recognized in geotechnical engineering. The factor of safety for piles is generally not as high as 6; typical values range around 2 to 3 (varying with design code, test data, and variability). Therefore, statement (d) is incorrect, making “All of these” wrong. The correct selection is the set containing (a), (b), and (c) only. Step-by-Step Solution: Verify (a): aligns with settlement-based working load definition → correct.Verify (b): describes ultimate behavior (continued sinking at essentially constant maximum load) → correct.Verify (c): safe capacity = ultimate / FOS → correct.Assess (d): FOS = 6 is excessive for piles; typical practice adopts 2–3 (sometimes different for tension or lateral) → incorrect.Therefore choose “(a), (b), and (c) are correct.” Verification / Alternative check: Pile load test interpretations and code guidance consistently use moderate safety factors, refined when static load test data are available. Why Other Options Are Wrong: Only (a) and (b): ignores correct statement (c).Only (d): statement (d) is incorrect.All/None: do not match the truth set. Common Pitfalls: Confusing geotechnical factor of safety with structural load factors; assuming a universal FOS irrespective of site data quality. Final Answer: (a), (b), and (c) are correct.

Question 3

Properties of sand used in building construction: Which statements are correct?

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Introduction / Context: Sand is a ubiquitous fine aggregate in concrete and mortar and is also used as a capillary break under floors. Understanding its composition and hydraulic behavior helps in selecting appropriate site practices. Given Data / Assumptions: Sand is predominantly silica (quartz) with grains produced by weathering and abrasion. Frost action refers to damage from freeze–thaw cycles. Capillary rise depends strongly on pore size; coarse, well-graded sand provides large pores and high permeability. Concept / Approach: (a) is a standard description: most natural sands are rich in silica from rock disintegration. (b) Quartz itself is stable during freezing; unlike porous stones or clays, individual grains do not suffer frost spalling. (c) Because sand has relatively large pore sizes and is permeable, it produces low capillary suction compared to silts/clays; a sand layer thus acts as a capillary break beneath floors and pavements, effectively preventing significant upward capillary rise. Step-by-Step Solution: Assess (a): true for common construction sands.Assess (b): quartz grains are inert to freeze–thaw → correct.Assess (c): coarse permeable sand interrupts capillary continuity → practically prevents capillary rise.Hence select “All of the above.” Verification / Alternative check: Soil mechanics shows capillary rise is inversely proportional to pore size; sands exhibit negligible capillary head compared to fines, supporting their use as capillary breaks. Why Other Options Are Wrong: Only (a) and (b) ignores the well-known capillary-break function of sand layers. Common Pitfalls: Using fine or silty sand that can still develop capillarity; not compacting the sand bed, allowing differential settlements. Final Answer: All of the above.

Question 4

Timber partitions: In a common wooden partition, the “sill” refers to which member?

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Introduction / Context: Wooden partitions and frames are defined by specific members: sill, head, studs, rails, and braces. Correct naming is important for drawings, bills of quantities, and onsite instructions. Given Data / Assumptions: A typical stud-and-rail timber partition frame. Standard nomenclature applies. Focus is on identifying the sill member. Concept / Approach: The “sill” is the lower horizontal member that rests on or is fixed to the floor and carries the studs above. The “head” is the upper horizontal member; “studs” are the verticals; “rails” or “noggings” are intermediate horizontals; end verticals are sometimes called posts. Step-by-Step Solution: Define the sill: bottom horizontal frame member.Differentiate from head (top), intermediate rails, and vertical posts.Select the correct description. Verification / Alternative check: Timber framing guides and carpentry manuals consistently name the bottom member as the sill or sole plate. Why Other Options Are Wrong: Vertical end member: that is a post or stud.Upper horizontal: the head, not the sill.Intermediate member: a rail/nogging.Diagonal brace: different function entirely. Common Pitfalls: Confusing “sill” with “window sill”; in partitions, sill refers to the lower frame piece along the floor. Final Answer: Lower horizontal member of the frame.

Question 5

Basic building terminology: “Ceiling height” of a room is measured as the vertical distance

Accepted Answer

Introduction / Context: Clear definitions of dimensional terms ensure consistency in drawings, approvals, and measurement for contracts. “Ceiling height” is a commonly specified dimension in building byelaws and ergonomics. Given Data / Assumptions: The room has a finished floor and a finished ceiling surface (plaster, false ceiling, or exposed slab). We need the definition applicable for habitable room height checks. Concept / Approach: Ceiling height is the vertical distance between the finished floor level (FFL) and the finished ceiling surface. Outdoor ground levels or roof levels are irrelevant to this interior dimension. Where a false ceiling is installed, most codes consider the clear height up to the lowest finished ceiling plane for habitable-space requirements. Step-by-Step Solution: Identify the two interior reference planes: finished floor and finished ceiling.Ignore external ground or roof references, as they do not define interior clear height.Select the description matching interior vertical clearance. Verification / Alternative check: Building codes specify minimum ceiling heights (e.g., around 2.6 m for main rooms in many jurisdictions) measured from FFL to finished ceiling/soffit. Why Other Options Are Wrong: Options involving ground or roof levels refer to external dimensions, not room interior clearance. Common Pitfalls: Measuring to the slab soffit when a lower false ceiling is present; not accounting for floor finishes thickness when checking minimum height. Final Answer: Between the finished ceiling and finished floor level of the same room.

Question 6

Brick masonry finishes: The type of pointing that forms a V-shaped projection proud of the wall face is called

Accepted Answer

Introduction / Context: Pointing is the finishing of mortar joints in exposed masonry. Different profiles are used to shed water, create shadows, or achieve a distinct architectural expression. Knowing the names helps when reading specifications and inspecting work.
 Given Data / Assumptions: The joint is finished with a V-shaped ridge formed beyond the wall face. Common pointing types include flush, recessed, weathered, vee (V), and tuck. Concept / Approach: V-pointing creates a raised V-shaped profile by tooling the joint mortar, projecting slightly from the wall face. Weathered pointing slopes outward to shed water; recessed pointing is pressed back from the brick face; tuck pointing uses a contrasting fillet to simulate fine joints; flush is struck level with the surface. Step-by-Step Solution: Match the described V-shaped projection with the standard name → V-pointing.Rule out weathered (sloping), recessed (set back), tuck (decorative fillet), and flush (level with face).Select “V-pointing.” Verification / Alternative check: Masonry handbooks illustrate the characteristic sharp V-tool ridge for this pointing profile. Why Other Options Are Wrong: Recessed/Flush: do not project from the face.Weathered: sloped, not V-shaped ridge.Tuck: uses narrow contrasting fillet, not a V ridge. Common Pitfalls: Over-projecting the ridge making it fragile; poor compaction leading to water ingress at the arrises. Final Answer: V-pointing.

Question 7

Foundations – eccentric loading: For a rectangular footing of width b, the allowable eccentricity of the resultant load (to avoid tension at the base) should not exceed

Accepted Answer

Introduction / Context: Eccentric loading on footings causes non-uniform base pressure. To keep the entire base in compression (no tension), the line of action of the resultant should lie within the “kern” or middle third of the footing section. This criterion is fundamental in foundation proportioning and checking. Given Data / Assumptions: Rectangular footing of width b (in the direction of eccentricity). Soil cannot take tension; we desire compression over the whole base. Linear elastic distribution of stress is assumed. Concept / Approach: For a rectangular section with linear stress distribution, full compression (no tension) occurs when the resultant compressive force passes within the kernel limits. Along a given axis, the kern limit equals b/6 from the centroid. If the eccentricity e exceeds b/6, the pressure at the opposite edge becomes zero or tensile, which is not permissible for soil. Step-by-Step Solution: Let the resultant load act at eccentricity e from the centroid.Edge pressure becomes zero when e = b/6; beyond this, tensile stress would develop.Therefore, the allowable eccentricity to keep entire base in compression is e ≤ b/6.Select “b/6.” Verification / Alternative check: Using the linear formula p = (P/A) ± (6P e)/(bA) shows that p_min ≥ 0 requires e ≤ b/6. Why Other Options Are Wrong: b/2, b/3, b/4, b/5: exceed the kern limit and would cause tension at the toe for many load cases. Common Pitfalls: Confusing middle third (b/6) with middle quarter (b/8); ignoring biaxial eccentricity and combined checks in both directions. Final Answer: b/6.

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