Question 1

Determinants of the rate of an item of work (civil estimation) Which factors does the unit rate of an item of work depend on in rate analysis and estimation?

Accepted Answer

Introduction / Context: Rate analysis derives the unit rate of an item (e.g., brickwork, plastering, concrete) from inputs like labour, materials, equipment, overheads, and profit. Item specifications and construction methodology directly affect consumption and productivity, and therefore the rate. Given Data / Assumptions: Standard civil engineering rate analysis framework. Quality and grade specifications influence quantities and costs. Construction method and productivity influence labour and equipment time. Concept / Approach: Rates are sensitive to the required quality (work and material specs), mix proportions (e.g., mortar ratios), and the adopted method (manual, semi-mechanised, mechanised). Changing any of these alters resource consumption per unit output. Step-by-Step Solution: 1) Specifications of works: tighter tolerances or finishes increase labour time.2) Specifications of materials: higher grades or special materials alter unit costs.3) Proportion of mortar: richer mixes raise cement consumption per m^3/m^2.4) Method of construction: mechanisation and site setup impact daily output and equipment costs. Verification / Alternative check: Compare the same item done manually vs with mixers/scaffolding systems; rates differ noticeably, demonstrating multi-factor dependence. Why Other Options Are Wrong: Any single option alone is incomplete; rates depend on all listed factors. Common Pitfalls: Ignoring productivity variations, local wage/material indices, wastage allowances, and site access in rate build-ups. Final Answer: All the above

Question 2

Centre-line method in estimation — suitable building shapes For which plan geometries is the centre-line method especially convenient and efficient for quantity estimation?

Accepted Answer

Introduction / Context: The centre-line method is a rapid technique for estimating quantities of walls, foundations, and superstructure where measurements are taken along the centre lines of walls. It is particularly effective when wall thickness is uniform or changes are systematic around the layout. Given Data / Assumptions: Plan shapes involve symmetry or repeating segments. Wall thickness is either constant or changes in a predictable way. Openings are adjusted systematically. Concept / Approach: By summing the lengths of centre lines and multiplying by uniform widths or depths, one obtains quantities quickly. For curved or polygonal plans (circular, hexagonal, octagonal, other regular polygons), centre-line computations simplify repetitive corner allowances and reduce arithmetic. Step-by-Step Solution: 1) Identify plan geometry: circular or polygonal with consistent wall thickness.2) Compute total centre-line length once, apply uniform breadth/depth factors.3) Adjust for openings and junction overlaps as per standard rules.4) Summarise quantities for foundations, plinth, and superstructure layers. Verification / Alternative check: Contrast with long-wall/short-wall method on polygonal plans; centre-line method reduces corner corrections and speeds up takeoff. Why Other Options Are Wrong: Each single geometry listed is indeed suited; therefore choosing only one is incomplete. Common Pitfalls: Forgetting to correct for wall junctions where double counting may occur; applying the method blindly when wall thickness varies irregularly. Final Answer: All the above

Question 3

Anti-siphonage connection for a water closet (W.C.) In sanitary plumbing, to prevent trap seal loss due to siphonage, the anti-siphonage (vent) pipe is connected to which location relative to the P-trap of the W.C.?

Accepted Answer

Introduction / Context: Trap seals prevent foul gases from the drainage system entering occupied spaces. During discharge, rapid flow can create negative pressure and siphon the water seal. Anti-siphonage (vent) pipes equalise pressure to protect the seal, a critical aspect of healthy plumbing design. Given Data / Assumptions: A P-trap is installed at the W.C. outlet. We need to connect a vent that prevents seal depletion during heavy discharge. Standard single-stack or two-pipe sanitary systems are considered. Concept / Approach: Anti-siphonage pipes are connected near the crown of the trap (top region) so that any pressure drop is immediately communicated to the atmosphere, preventing the formation of a siphon and retaining the water seal depth. Step-by-Step Solution: 1) Locate the P-trap of the W.C.; identify the crown (top) region of the water seal.2) Provide a vent/anti-siphonage connection at or near the top of the P-trap.3) Route the anti-siphonage pipe to connect with the vent stack or to open air as per code.4) Verify gradients and junctions to avoid self-siphonage and ensure self-cleansing velocity in the discharge pipe. Verification / Alternative check: Fixture unit calculations often require vent sizing; code diagrams consistently show anti-siphonage taken off at the top of the trap seal region. Why Other Options Are Wrong: Main soil pipe: Venting at the stack alone may not protect the local trap under surge discharge. Bottom of P-trap: Does not relieve suction; also risks deposit accumulation. Side of W.C.: Not the functional location for pressure equalisation at the seal. None of these: Incorrect because the correct connection is at the top of the P-trap. Common Pitfalls: Placing the vent too far downstream; using undersized vents; sharp bends near the trap creating air locks. Final Answer: Top of P-trap W.C.

Question 4

Estimation & Measurement – Identify the incorrect rule In civil engineering quantity measurement (as per standard practice like IS 1200), which of the following statements about deductions is NOT correct?

Accepted Answer

Introduction / Context: Estimating and costing in civil engineering follow codified measurement rules (e.g., IS 1200 series). These rules specify when deductions are or are not made for small openings, embedded items, pipes, and the ends of members. The question tests recognition of the standard thresholds and the contexts (concrete, masonry, plaster). Given Data / Assumptions: General building works under standard measurement rules. Typical items: RCC concrete, brick masonry, plastering, small service penetrations, ends of beams/posts. Threshold areas are used to simplify measurement for small interruptions. Concept / Approach: Each statement corresponds to a common rule. We check whether the threshold magnitude and the work context match standard practice. In particular, plastering has a larger no-deduction threshold for ends of members than 500 cm^2. Step-by-Step Solution: 1) Reinforcement in RCC: Concrete volume is measured without deducting steel; statement (a) is correct.2) Openings in masonry: Very small openings (about 0.1 m^2) are commonly ignored; statement (b) is correct.3) Small pipes/conduits: Very small pipe penetrations (on the order of 100 cm^2 cross-section) are often ignored in practice; statement (c) is acceptable.4) Plastering ends of dissimilar members: The customary no-deduction limit is around 0.5 m^2 (5000 cm^2), not 500 cm^2; (d) understates the threshold and is therefore incorrect. Verification / Alternative check: Cross-reference common clauses: concrete measurements exclude steel; masonry ignores tiny openings; plastering uses a relatively generous threshold for ends of beams/posts (about 0.5 m^2). The mismatch in (d) confirms it as the incorrect statement. Why Other Options Are Wrong: (a) Standard RCC practice; no deduction made for steel volume. (b) Tiny openings in masonry are ignored to simplify measurement. (c) Very small pipe voids are ignored; threshold scale is reasonable. (e) “None of these” is wrong because (d) is indeed incorrect. Common Pitfalls: Mixing the rules for plaster, masonry, and concrete, or confusing units of m^2 versus cm^2 can lead to wrong judgments about thresholds. Final Answer: No deductions are made for the ends of dissimilar members up to 500 cm^2 cross-sectional area in plastering

Question 5

Highway Embankment – Cross-sectional area (no camber) For a highway embankment with formation width B, height d, and side slope S:1 (horizontal:vertical), and with no transverse slope (no camber), what is the cross-sectional area?

Accepted Answer

Introduction / Context: In highway earthwork estimation, the cross-sectional area of an embankment depends on formation width, height, and side slopes. With no camber (transverse slope = 0), the geometry simplifies to a central rectangle plus two similar right triangles. Given Data / Assumptions: Formation width = B (at the top). Embankment height = d. Side slope = S horizontal : 1 vertical. No transverse slope (flat top). Concept / Approach: Area consists of a rectangle (B by d) plus two triangular side prisms each with base S d and height d. The two triangles combine to S d^2. Step-by-Step Solution: Rectangular core area = B * dArea of one side triangle = 1/2 * (S d) * d = (S d^2)/2Two sides ⇒ total triangular area = S d^2Total cross-sectional area A = B d + S d^2 Verification / Alternative check: Dimensional consistency: each term has length^2. If S = 0 (vertical sides), A reduces to B d, as expected. Why Other Options Are Wrong: (a) and (c) have wrong forms and/or units. (b) matches the correct expression but (d) presents it more clearly with parentheses; both (b) and (d) are equivalent, but (d) is the clean standard form. (e) is incorrect because a correct expression exists. Common Pitfalls: Confusing S:1 with 1:S, or forgetting that both sides contribute S d^2 when summing the triangular areas. Final Answer: (B d + S d^2)

Question 6

Rate Units – Items paid per 100 cubic metres (% cu m) For which of the following items is the rate commonly quoted per 100 m^3 (also written as per “% cu m”)?

Accepted Answer

Introduction / Context: In schedule of rates and bills of quantities, certain bulk earthwork operations are priced per 100 m^3 (commonly denoted “% cu m”) to standardize large-volume tasks and simplify tendering. Given Data / Assumptions: Bulk earthwork items across excavation, trenching, rock cutting, and filling. Measurement in cubic metres. Conventional rate quotation practices. Concept / Approach: Items involving large volumes and similar handling are grouped under the per-100-m^3 convention. This includes general excavation, trench excavation (measured in m^3 by section method), rock cutting, and earth filling in plinths. Step-by-Step Solution: Identify all earthwork-like items in the list.Confirm that each is measured in m^3.Confirm that per-100-m^3 rate convention is applicable to all. Verification / Alternative check: Standard schedules (e.g., PWD/SOR) show “per 100 m^3” entries for bulk excavation, rock cutting (by volume), and earth filling items. Why Other Options Are Wrong: Options a–d are each correct on their own; hence “All of the above” is the best choice. Common Pitfalls: Confusing “per m^3” with “per 100 m^3” or assuming trench excavation is always per running metre; in estimation it is typically volumetric unless specifically stated otherwise. Final Answer: All of the above

Question 7

Plumbing Measurement – Pipe classification and measurement rules Which of the following statements about pipe works and their measurement is correct?

Accepted Answer

Introduction / Context: Plumbing items in bills of quantities are standardized for classification, sizing, and measurement. Understanding how diameters are defined and how lengths and special joints are measured helps ensure correct take-off and costing. Given Data / Assumptions: Conventional pipe measurement in building services. Use of nominal sizes for cataloging. Separate enumeration for special joints. Concept / Approach: Classification is based on diameter groups; nominal diameter represents internal bore for common metallic pipes; linear measurement follows the centre line of the run; and special joints (e.g., lead caulked) are counted separately to reflect extra labour and materials. Step-by-Step Solution: Check classification basis ⇒ diameter.Interpret “diameter” ⇒ nominal internal bore for standard specifications.Measurement along centre line ⇒ metres of run.Special joints ⇒ enumerated separately. Verification / Alternative check: Standard measurement codes and SORs list pipework by nominal diameter and measure runs in metres with separate items for joints/fittings where applicable. Why Other Options Are Wrong: a–d are all correct statements; hence “All of the above” is correct. Common Pitfalls: Mixing nominal bore with outside diameter, or forgetting to enumerate non-standard joints separately leads to underestimation. Final Answer: All of the above

Question 8

Estimating Basics – Contingencies, work-charged staff, detailed specs, and market rate Which of the following statements is correct in the context of preparing detailed estimates?

Accepted Answer

Introduction / Context: Accurate estimates rely on clear terminology: contingencies, work-charged establishment, detailed specifications, and market rate. Knowing these definitions avoids omissions and mispricing in tenders and DPRs (Detailed Project Reports). Given Data / Assumptions: Standard building works estimate. Need to include non-measurable incidentals, staffing, material requirements, and prevailing rates. Concept / Approach: Each term has a specific meaning in estimating practice, guiding how costs are grouped and justified in the BOQ and the summary sheet. Step-by-Step Solution: Contingencies ⇒ provision for unforeseen, incidental expenditure.Work-charged establishment ⇒ staff wages charged directly to the work during execution.Detailed specifications ⇒ technical prescription of material quality, proportion, workmanship, and tests.Market rate ⇒ current open-market procurement price per unit. Verification / Alternative check: These align with textbook and code definitions used in government estimates and CPWD practice. Why Other Options Are Wrong: a–d are each correct, so “All of the above” is the correct combined choice. Common Pitfalls: Confusing contingencies with provisions for price escalation, or misclassifying permanent staff under work-charged establishment, may distort budget lines. Final Answer: All of the above

Question 9

Sanitation – Trap that disconnects a house drain from the public sewer What is the name of the trap installed to isolate the house drainage system from the street sewer, usually inside an intercepting chamber near the property boundary?

Accepted Answer

Introduction / Context: House drainage must be protected from foul gases and backflow from the public sewer. A dedicated trap is provided near the property boundary inside a manhole to disconnect the house drain from the municipal sewer line. Given Data / Assumptions: Conventional building drainage per common practice. Device located at the last manhole before connecting to the public sewer. Purpose: block sewer gases and provide a cleaning eye. Concept / Approach: An intercepting trap (often called a master trap colloquially) provides a deep water seal at the junction to the public sewer. The manhole is termed an intercepting or inspection chamber, but the trap itself is specifically the intercepting trap. Step-by-Step Solution: Identify component whose function is to disconnect: the trap element.Name of the trap: Intercepting trap.Associated structures (manhole/chamber) house the trap but are not the trap. Verification / Alternative check: Standard sanitation layouts show a deep-seal intercepting trap just upstream of the public sewer connection inside the intercepting chamber. Why Other Options Are Wrong: Master trap: colloquial synonym used inconsistently; the standard term is “intercepting trap”. Interception manhole / Intercepting chamber: these are structures, not the trap device. All of the above: mixes device name with housing structures; not precise. Common Pitfalls: Confusing the chamber/manhole with the trap inside, or treating a colloquial name as a formal specification term. Final Answer: Intercepting trap

Question 10

Payment Units – Common materials and their standard units in BOQ Which of the following statements correctly pairs the material with the usual unit of payment?

Accepted Answer

Introduction / Context: BOQ unit conventions reduce ambiguity in supply and measurement. Bricks, cement, lime, and aggregates have standard units of account widely used in schedules of rates and tender documents. Given Data / Assumptions: Standard materials for masonry and concrete. Prevailing practice in government/CPWD/PWD schedules. Concept / Approach: Identify the most common unit used in pricing and supply for each material and confirm consistency with mainstream schedules of rates. Step-by-Step Solution: Bricks ⇒ per thousand (1000 nos.).Cement ⇒ per 50 kg bag.Lime ⇒ per quintal (100 kg).Brick aggregate ⇒ per cubic metre (m^3). Verification / Alternative check: Cross-checks with typical SOR/BOQ templates confirm these units are standard entries for procurement and billing. Why Other Options Are Wrong: a–d are each correct; hence the combined choice is “All of the above”. Common Pitfalls: Confusing “per tonne” versus “per quintal” for lime, or quoting aggregate by tonne instead of the volumetric unit specified in the BOQ. Final Answer: All of the above

Question 11

Productivity – Expected out-turn for a half-brick partition wall What is the typical expected out-turn (productivity) per mason per day for constructing a half-brick (about 115 mm thick) partition wall?

Accepted Answer

Introduction / Context: Expected out-turn helps planners estimate labour requirements, duration, and cost. For partition walls, productivity is measured by surface area (m^2) instead of volume, because thickness is standard and small. Given Data / Assumptions: Half-brick wall ≈ 115 mm thick using common bricks. Average working conditions and normal course heights. Skilled mason with helper(s), typical 8-hour shift. Concept / Approach: Industry thumb rules place half-brick masonry productivity around 4–6 m^2 per mason per day, depending on site factors. A commonly adopted nominal for planning is 5.0 m^2/day. Step-by-Step Solution: Identify measure ⇒ area in m^2 for half-brick partitions.Adopt standard nominal value from schedule norms ⇒ 5.0 m^2/mason/day.Check plausibility against typical range (4–6 m^2) ⇒ within range. Verification / Alternative check: Productivity norms in departmental handbooks commonly quote 5.0 m^2/day as a planning basis for half-brick partitions under average conditions. Why Other Options Are Wrong: 1.5 m^3 and 2.0 m^3: incorrect unit (volume), not the conventional surface measure. 4.0 m^2: on the low side for average conditions. 6.5 m^2: optimistic and not a conservative planning value. Common Pitfalls: Confusing m^2 with m^3 or using rates for full-brick masonry, which are significantly different. Final Answer: 5.0 m^2

Question 12

Building Area Metrics – What carpet area excludes Carpet area is the usable floor area within the internal finished faces of walls. Which of the following are excluded from carpet area for the purpose of traditional building estimation?

Accepted Answer

Introduction / Context: Different area metrics are used in building planning and valuation: plinth area, carpet area, and saleable/super area. Traditional estimation texts define carpet area as the net usable area of rooms, excluding walls and several ancillary spaces. This question checks what is excluded. Given Data / Assumptions: Conventional estimation (textbook) definition of carpet area used in BOQ/estimation problems. Not the later statutory definitions for real‐estate regulation which may vary. Concept / Approach: Carpet area (traditional) = plinth area − (wall thickness + verandahs/corridors/passages + service spaces like baths/WC, and in many estimating texts, kitchens/pantries). Hence multiple listed items are excluded. Step-by-Step Solution: Identify items that are non-usable circulation or service spaces ⇒ verandah, corridor, passage.Remove wall thickness and wall-embedded openings from usable area ⇒ excluded.Service spaces like bathrooms/WC are excluded in traditional estimation norms.In many classical estimation references, kitchens/pantries are also excluded from carpet computations for planning ratios ⇒ excluded. Verification / Alternative check: Older estimating practice and examination standards commonly treat all listed elements as exclusions when computing carpet area for academic problems. Why Other Options Are Wrong: a–d individually represent categories excluded in the conventional estimation context; therefore “All of the above” is correct. Common Pitfalls: Using modern regulatory definitions (e.g., RERA) which include kitchens and toilets within carpet area can cause confusion; always follow the convention specified by the syllabus or problem statement. Final Answer: All of the above

Question 13

Quantity Surveying – When is brickwork NOT measured in cubic metres? In civil engineering measurement (IS 1200 practice), brickwork items are generally measured by volume (cubic metres). Identify the case where brickwork is measured by area instead,…

Accepted Answer

Introduction / Context: Accurate quantity take-off depends on using the correct unit of measurement for each item. In building works, brick masonry is usually measured in cubic metres because it is a volumetric work. However, some thin or special configurations are measured differently to align with how the work is executed and paid in practice. Given Data / Assumptions: Standard measurement practice as per common schedules and IS-style conventions. Brickwork thickness categories: half-brick (about 115 mm), one-brick (about 230 mm), and thicker. Arches and reinforced brickwork are still masonry items requiring volume-based assessment unless specified otherwise. Concept / Approach: Conventionally, full-thickness brick masonry is measured in cubic metres because both thickness and height are significant and vary. For thin partitions (about half-brick), the work is practically planar and best captured by area measurement (square metres), with thickness stated separately. This reflects site practice and provides clearer rate analysis (including bond, stiffeners, and support details). Step-by-Step Solution: Identify items usually in m^3: full-thickness walls, reinforced brickwork, arches (unless exceptionally specified).Identify thin/planar item: half-brick partition is effectively a wall by area.Therefore, the case NOT measured in m^3 is the half-brick partition wall (measured in m^2). Verification / Alternative check: Check standard Bill of Quantities: half-brick partition lines appear with m^2 units, thickness noted; full-thickness walls appear in m^3 with deductions and additions for openings/bond beams. Why Other Options Are Wrong: One-brick walls, arches, and reinforced brickwork are volumetric; brick nogging is typically counted differently or by area/number but is not the standard contrast used in this question. Common Pitfalls: Assuming all brickwork is m^3 regardless of thickness; forgetting that thin partitions attract m^2 measurement to reflect construction method and pricing. Final Answer: Half-brick (about 115 mm) partition wall

Question 14

Building Bye-laws – Inclusion of balcony in floor area/FAR computation For the purpose of calculating permissible floor area or Floor Area Ratio (FAR), up to what percentage of a balcony's area is typically counted towards the floor area in standard…

Accepted Answer

Introduction / Context: Municipal bye-laws and development control rules define how to compute Floor Area Ratio (FAR) or built-up area. Balconies, projections, and ducts often have special treatment so that designs encourage light and ventilation without overly inflating chargeable area. A common convention is to count only a portion of balcony area in the floor area calculation. Given Data / Assumptions: Generic Indian practice where balcony area is partly chargeable. Local bye-laws can vary, but a typical allowance exists in many jurisdictions. We assume standard residential building rules in absence of a specific city code. Concept / Approach: To balance livability and density control, many authorities include only a fraction of balcony area in the FAR computation (often one-half). Designers must always confirm the local Development Control Regulations (DCR), but 50% is a widely cited norm used in preliminary estimates and examinations. Step-by-Step Solution: Identify typical fraction applied to balconies for FAR: many schedules apply 50% inclusion.Therefore, the included area for balconies is taken as 50% of the actual balcony area for FAR calculations. Verification / Alternative check: Sample DCRs from several Indian cities reflect partial inclusion of balcony area (often 50%), confirming the rule-of-thumb used in academic and competitive exams. Always verify the exact clause for a specific municipality. Why Other Options Are Wrong: 100% or 75% overestimates the chargeable area in places with concessions; 25% or 0% underestimates and is uncommon for general guidance. Common Pitfalls: Confusing balcony with terrace or covered verandah; assuming universal rules without checking city-specific notifications. Final Answer: 50%

Question 15

Earthwork Measurement – Items not measured separately Which of the following operations associated with earthwork are generally deemed to be included in the earthwork rate and therefore are not measured separately for payment?

Accepted Answer

Introduction / Context: Standard methods of measurement streamline BOQ preparation by stating which incidental activities are covered by the main item rate. In earthwork, several auxiliary operations are treated as included in the excavation or embankment rate to avoid excessive fragmentation of items and to reflect normal contractor obligations. Given Data / Assumptions: Earthwork in excavation or embankment as per typical IS-style measurement. Ancillary activities considered part of the main rate unless specifically stated otherwise. Safety and control measures like dead men/bench marks are customary. Concept / Approach: Measurement rules identify operations that are necessary adjuncts: setting out, clearing, dead men/bench marks for level control, and steps/benches for safe and accurate excavation. These are usually not measured as separate BOQ line items; they are included within the quoted rate for earthwork. Step-by-Step Solution: Check each option against standard inclusions lists.Setting out: included with main work unless specifically paid under preliminaries.Site clearance: generally included before excavation unless heavy jungle or special clearance is specified.Dead men/bench marks: included for measurement control.Steps/benches: included as part of proper execution in deep cuts.Therefore, all items are not measured separately. Verification / Alternative check: Review typical BOQs and IS 1200-type notes: these tasks appear under inclusions or preliminaries, not as separate earthwork sub-items. Why Other Options Are Wrong: Any single selection would omit other equally included tasks, contradicting the standard inclusion principle. Common Pitfalls: Paying twice by adding separate items; overlooking special specifications where exceptional circumstances justify separate payment. Final Answer: All of the above

Question 16

Units of Measurement – When is square metre (m^2) used? Choose the item that is typically measured in square metres for BOQ purposes (with thickness specified), rather than in cubic metres, numbers, or tonnes.

Accepted Answer

Introduction / Context: Selecting the correct unit of measurement improves comparability of rates and clarity in BOQs. Masonry and blockwork are often priced by area when the thickness is standard, while mass or volume-based items (concrete) are measured by cubic metres. Discrete items like posts are counted by number. Given Data / Assumptions: Standard IS-style measurement conventions. Walls built with hollow concrete blocks of a given thickness (for example, 100 mm, 150 mm). Concrete in structural members is volumetric work. Concept / Approach: Block masonry walls are planar elements; the BOQ usually states thickness and measures the area in m^2. Concrete in foundations or RCC frames is measured by volume (m^3) because the thickness and geometry vary. Precast elements like fencing posts are counted by number with size and grade stated. Step-by-Step Solution: Identify planar masonry: hollow block wall → m^2 with thickness note.Identify volumetric concrete: PCC and RCC → m^3.Identify discrete units: fencing posts → number (No.).Therefore, the correct choice is hollow concrete block walling. Verification / Alternative check: Check typical BOQs and SORs: block masonry lines show m^2, concrete lines show m^3, and posts appear under numbers. Why Other Options Are Wrong: PCC and RCC are measured in m^3; posts are per number; “None of these” is invalid since block walling fits the m^2 unit. Common Pitfalls: Confusing blockwork with concrete; omitting thickness specification for m^2 items. Final Answer: Hollow concrete block walling (specified thickness)

Question 17

Plumbing Detailing – Slope of P-trap outlet below horizontal In sanitary plumbing, the outlet of a P-trap is laid with a small downward inclination to ensure self-cleansing flow. What is the standard slope angle of the P-trap outlet below the horizo…

Accepted Answer

Introduction / Context: Traps are essential fittings that maintain a liquid seal to block sewer gases while allowing wastewater to pass. Providing a slight downward slope at the trap outlet aids self-cleansing velocities, minimizes deposition, and reduces maintenance issues in household drainage systems. Given Data / Assumptions: Standard domestic sanitary installation with a P-trap at the appliance outlet. Outlet requires a modest inclination below the horizontal. Typical Indian plumbing practice and exam standards apply. Concept / Approach: The slope must be sufficient to promote gravity flow but not so steep as to compromise water seal stability or fixture alignment. An angle around twelve degrees strikes the balance widely adopted in practice. Step-by-Step Solution: Identify common recommended outlet inclination for P-traps.Check that the angle ensures self-cleansing without siphoning effects.Standard value used in many schedules and teaching references: 12° below horizontal. Verification / Alternative check: Survey of typical detailing guides and question banks shows 12° frequently cited for P-trap outlet inclination where a discrete angle is asked rather than a gradient ratio. Why Other Options Are Wrong: 8° and 10° may be inadequate for self-cleansing under low discharge; 14° is steeper than customary; 6° is too flat for reliable scouring. Common Pitfalls: Confusing P-trap outlet slope with pipe gradients given in ratios (for example, 1 in 40); mixing pan outlet angle values with trap outlet inclination. Final Answer: 12°

Question 18

Earthwork – Statements that are correct regarding excavation and embankment Which of the following statements correctly describe standard practice for earthwork operations and measurement?

Accepted Answer

Introduction / Context: Earthwork execution and measurement rely on tried-and-tested field procedures to ensure safety, accuracy, and quality. Examinations frequently test recognition of these practices so that engineers can specify, supervise, and measure work consistently with standard codes and SORs. Given Data / Assumptions: Borrow pit excavation for filling or embankment. Levelling instruments used for pre- and post-work levels. Road embankment constructed in controlled layers to a designed profile. Concept / Approach: Each option corresponds to a standard practice: leaving dead men to determine average depth, computing quantities from level grids and RL differences, and executing embankment in layers to the specified density and profile. Together, they form a coherent set of procedures for both quantity measurement and quality control. Step-by-Step Solution: Option A: Dead men provide reference surfaces for measuring excavation depths reliably.Option B: Quantities are obtained from pre- and post-excavation levels using grids or cross-sections.Option C: Embankments are placed in layers, trimmed/rolled to the correct camber and profile, achieving compaction standards.Therefore, all statements are correct. Verification / Alternative check: Field textbooks and IS-type methods of measurement confirm all three statements as standard practice across departments. Why Other Options Are Wrong: Choosing any single statement would wrongly imply that others are incorrect, which is not the case. Common Pitfalls: Ignoring dead men and relying on guesswork; skipping level books; constructing embankments without layer-wise compaction or profile control. Final Answer: All of the above.

Question 19

Lead in Earthwork – Identify the incorrect statement Consider the following statements about lead (horizontal hauling distance) in earthwork measurement and payment. Which statement is incorrect as per common IS-style practice?

Accepted Answer

Introduction / Context: Lead and lift are fundamental to pricing earthwork haul. Misinterpreting their definitions can distort quantities, rates, and logistics planning. Examinations often include conceptual questions to ensure engineers internalize the correct measurement basis for transporting soil from cut to fill. Given Data / Assumptions: Standard departmental schedules and IS 1200-style conventions. Borrow and spoil/embankment locations identifiable on drawings. Average haul used for payment unless special haul roads or staged dumps are specified. Concept / Approach: Lead is not determined for every micro-block of excavation. Instead, it is measured as the straight-line horizontal distance between the centroid (center of gravity) of the excavation area and the centroid of the fill area. For short hauls, schedules commonly adopt 50 m lead units up to about 500 m; for long hauls beyond about 2 km, 1 km units are used. Step-by-Step Solution: Define lead correctly: horizontal distance between centroids of cut and fill.Check unit practice: 50 m steps up to roughly 500 m; beyond long haul, 1 km steps.Evaluate statements: options A, C, D, and E align with standard practice; option B suggests per-block calculation, which is incorrect. Verification / Alternative check: Typical SOR notes and MoRTH/departmental specifications use centroid-to-centroid lead; project-specific methods only deviate when explicitly stated. Why Other Options Are Wrong: They are not wrong: A, C, D, and E are consistent with standard definitions and unit steps for lead. Common Pitfalls: Measuring along haul roads instead of straight distance for payment; ignoring separate items for extra lead; confusing lead (horizontal) with lift (vertical). Final Answer: Lead is calculated separately for each small block within the excavated area.

Question 20

Productivity – Out-turn of excavation by one mazdoor per day in ordinary soil What is the expected out-turn (quantity of earthwork) that one mazdoor can excavate in ordinary soil in one working day under normal conditions?

Accepted Answer

Introduction / Context: Labour productivity norms are used to plan resources, estimate duration, and prepare unit-rate analyses. For small-scale or manual earthwork in ordinary soil, out-turn per worker per day is tabulated in many schedules and serves as a baseline for planning. Given Data / Assumptions: Ordinary soil (no rock, no extensive roots or boulders). Hand excavation using standard tools under normal site conditions. Typical 8-hour working day and average labour skill/pace. Concept / Approach: Out-turn depends on soil type, depth, disposal lead/lift, and weather. In ordinary soil with short lead and standard lift, a commonly used planning norm is about 2 cubic metres per mazdoor per day. This figure is indicative for preliminary estimation and should be adjusted by productivity studies for project-specific conditions. Step-by-Step Solution: Identify soil: ordinary, not hard/dense.Identify method: manual excavation, no special constraints.Apply standard norm: ~2.00 m^3 per mazdoor-day. Verification / Alternative check: Cross-reference departmental schedules and textbooks: typical ranges of 1.5–2.5 m^3 are cited; 2.00 m^3 is a conventional planning value used in exam questions. Why Other Options Are Wrong: 1.00 m^3 is conservative for ordinary soil; 3.00–4.00 m^3 are optimistic for average conditions; 0.75 m^3 is too low absent constraints. Common Pitfalls: Assuming the same output for hard soil or rock; ignoring effects of waterlogging, disposal distance, and team composition (mazdoor, beldar, mate). Final Answer: 2.00 cum

Estimating and Costing Questions