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CTVET Ghana Certificate II - Blocklaying & Concreting study materials
CTVET Ghana Certificate II - Blocklaying & Concreting study resources

CTVET Ghana Certificate II - Blocklaying & Concreting practice questions

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Question 1Occupational Health, Safety and Environment on Site

On a Ghanaian site, which item of personal protective equipment is specifically required when you are laying blocks above shoulder height and there is a risk of falling material striking your head?

  1. Steel-toe boots
  2. Dust mask
  3. High-visibility vest
  4. Safety helmet Correct answer.

Explanation

A safety helmet is designed to absorb impact from falling objects and is the standard control for overhead work such as laying blocks at height. A vest improves visibility, boots protect the feet and a dust mask protects the lungs, so none of them guards the head against falling material.

Question 2Occupational Health, Safety and Environment on Site

A blocklayer is about to cut blocks with a powered disc cutter. Which control should be applied first, before relying on personal protective equipment?

  1. Posting a warning sign at the site entrance
  2. Rotating operators every two hours
  3. Water suppression or dust extraction at the cutting point Correct answer.
  4. Issuing a disposable dust mask to the operator

Explanation

The hierarchy of control places elimination and engineering controls above PPE. Suppressing dust at source with water or extraction removes the hazard before it reaches the worker, whereas masks, rotation and signs only reduce exposure after dust is released.

Question 3Occupational Health, Safety and Environment on Site

Which of the following best describes a safe method of stacking concrete blocks on site?

  1. Pile them loosely beside an open excavation
  2. Stack them as high as possible to save space near the mixing area
  3. Stack them in stable, height-limited rows on firm level ground away from walkways Correct answer.
  4. Lean them against the site fence for easy access

Explanation

Blocks must be stacked on firm, level ground in stable, height-limited rows so the stack cannot topple. Keeping stacks away from walkways and excavations prevents collapse onto people and stops surcharge loading near trench edges.

Question 4Occupational Health, Safety and Environment on Site

You need to work in a deep trench to set the foundation blockwork. Which precaution is essential before anyone enters?

  1. A colleague stands at the top to shout if the sides move
  2. A competent person has inspected the trench and it is supported or battered to a safe angle Correct answer.
  3. The trench is entered quickly in the morning before the sun softens the soil
  4. Water is poured on the sides to settle the soil

Explanation

Before entry, a competent person must inspect the excavation and ensure the sides are supported, battered back or otherwise made safe against collapse. A look-out cannot prevent a collapse, and wetting or rushing entry increases the risk.

Question 5Occupational Health, Safety and Environment on Site

When mixing concrete by hand on site, which practice best protects the skin from cement burns?

  1. Apply barrier cream once in the morning and work all day
  2. Work bare-handed so you can feel the mix consistency
  3. Wear cotton garden gloves only
  4. Wear waterproof gloves and long sleeves, and wash off any cement contact promptly Correct answer.

Explanation

Wet cement is alkaline and abrasive, so waterproof gloves, long sleeves and prompt washing are the recognised controls against cement dermatitis and burns. Bare hands, absorbent cotton gloves and a single application of cream do not provide sustained protection.

Question 6Occupational Health, Safety and Environment on Site

A worker is using a petrol-driven concrete mixer in a closed site store. What is the main hazard and the correct control?

  1. Fire from the concrete; add more water
  2. Carbon monoxide build-up; operate the mixer outdoors or in a well-ventilated area Correct answer.
  3. Noise; simply close the store door
  4. Vibration; hold the mixer steady

Explanation

Petrol engines release carbon monoxide, an odourless gas that can accumulate to lethal levels in enclosed spaces. Running such equipment outdoors or with forced ventilation keeps the gas below harmful concentrations.

Question 7Occupational Health, Safety and Environment on Site

Before using a scaffold to lay blocks on a first-floor wall, which check confirms the platform is safe to use?

  1. It has been erected and inspected by a competent person, with guardrails, toe boards and a safe means of access Correct answer.
  2. Workers have agreed among themselves that it feels steady
  3. It looks level from the ground
  4. It was used yesterday without incident

Explanation

Scaffolds must be erected and inspected by a competent person and fitted with guardrails, toe boards and safe access before use. Visual impressions, informal agreement and past use do not confirm structural adequacy.

Question 8Occupational Health, Safety and Environment on Site

Which of these is the most appropriate first-aid response for a small fresh cut on a blocklayer's hand?

  1. Rinse it with wet mortar and carry on
  2. Wrap it in a cement bag and continue laying
  3. Ignore it until the end of the shift
  4. Stop work, clean the wound, apply a sterile dressing and report the injury Correct answer.

Explanation

Minor wounds must be cleaned and covered with a sterile dressing, and the injury should be reported so it is recorded. Covering with cement bag material or mortar introduces contamination and delays proper treatment.

Question 9Occupational Health, Safety and Environment on Site

A site is beside a busy road and blockwork is being laid close to the boundary. Which control best protects the public from falling materials?

  1. Rely on workers to shout a warning before dropping anything
  2. Ask pedestrians to walk faster past the site
  3. Erect a rigid fan or catch platform and debris netting along the boundary Correct answer.
  4. Place a single cone at the gate

Explanation

A rigid fan or catch platform with debris netting is an engineering control that physically intercepts falling materials at the site boundary. Cones, verbal warnings and requests to pedestrians do not stop a falling block.

Question 10Occupational Health, Safety and Environment on Site

What does the term 'permit to work' mean in the context of a hot work task such as cutting reinforcement with a disc cutter that throws sparks?

  1. A receipt for the hire of the equipment
  2. A formal written authorisation confirming hazards are assessed and controls are in place before work starts Correct answer.
  3. A licence proving the operator owns the cutting tool
  4. A verbal agreement between two workers

Explanation

A permit to work is a formal documented authorisation issued after the hazards have been assessed and the controls verified, and it is closed out when the task ends. It is not proof of ownership, an informal chat or a hire document.

Question 11Occupational Health, Safety and Environment on Site

Concrete is being placed into formwork and a worker must vibrate it. Which combination of hazards is most directly associated with the poker vibrator?

  1. Manual handling and sunburn
  2. Hand-arm vibration and electric shock from a damaged cable Correct answer.
  3. Noise and cement burns
  4. Dust inhalation and eye strain

Explanation

Poker vibrators expose operators to hand-arm vibration over long periods and to electric shock if the supply cable or tool is damaged. Dust, cement burns and manual handling are real site hazards but are not the primary risks of the vibrator itself.

Question 12Occupational Health, Safety and Environment on Site

Which of the following is the correct way to store and handle lime and cement bags to control dust exposure?

  1. Store bags in an open area next to a walkway so they are easy to reach
  2. Keep bags in a covered, ventilated store and handle them gently to avoid raising dust Correct answer.
  3. Stack bags against the site office window for shade
  4. Tear bags open with a sharp kick to speed up emptying

Explanation

Cement and lime dust is harmful to the lungs, so bags should be kept dry in a covered, ventilated store and handled gently to minimise dust. Rough handling, open storage and blocking windows all increase dust and risk.

Question 13Occupational Health, Safety and Environment on Site

A worker is asked to move a heavy concrete lintel by hand with a colleague. Which technique is correct?

  1. Carry it alone with arms outstretched
  2. Lift with a twisted back to save time
  3. Assess the load, share it with a team, keep the back straight and lift with the legs Correct answer.
  4. Drag it along the ground while bent over

Explanation

Heavy components should be assessed before lifting and moved with adequate help or mechanical aids, using a straight back and leg muscles to reduce spinal loading. Twisting, carrying at arm's length and dragging while bent all increase injury risk.

Question 14Occupational Health, Safety and Environment on Site

Why is it important to keep site walkways clear of mortar droppings, offcuts and loose blocks during blocklaying work?

  1. To reduce the amount of cement used
  2. To prevent slips, trips and falls, which are among the most common site injuries Correct answer.
  3. To speed up the mortar setting time
  4. To make the site look tidy for the client

Explanation

Housekeeping controls slips, trips and falls by removing the debris that causes them, and it also keeps escape routes usable in an emergency. Appearance, material use and setting time are not safety reasons for clearing walkways.

Question 15Occupational Health, Safety and Environment on Site

A blocklayer notices a live electrical cable lying across the ground where barrows are pushed. What is the correct immediate action?

  1. Step over the cable carefully and continue working
  2. Cover the cable with a block and carry on
  3. Stop work in the area, keep people away and report it to the supervisor for isolation Correct answer.
  4. Move the cable with a metal barrow handle

Explanation

A damaged or trailing live cable is an electrocution risk, so work must stop, the area must be kept clear and the supply isolated by an authorised person. Stepping over, moving with metal or covering the cable leaves the hazard live.

Question 16Occupational Health, Safety and Environment on Site

Which of the following correctly describes the purpose of a toolbox talk before starting blockwork on a new section of the site?

  1. To record the quantity of blocks delivered
  2. To brief the crew on the specific hazards, controls and method for that task Correct answer.
  3. To check the accuracy of the setting-out lines
  4. To agree the wage rate for the day

Explanation

A toolbox talk is a short briefing that communicates the task-specific hazards, controls and method to the crew before work starts. Stock records, setting-out accuracy and pay are unrelated to this safety briefing.

Question 17Occupational Health, Safety and Environment on Site

A worker complains of dizziness and headache while working in a hot, enclosed block store during the afternoon. What is the most likely cause and the correct response?

  1. Carbon monoxide poisoning; continue working to finish the task
  2. Cement dermatitis; apply more cement
  3. Noise exposure; turn up the radio
  4. Heat stress or dehydration; move the worker to a cool ventilated area, give water and seek first aid Correct answer.

Explanation

Dizziness and headache in a hot, enclosed space suggest heat stress or dehydration, so the worker should be cooled, rehydrated and assessed. Continuing work, applying cement or increasing noise would worsen the situation.

Question 18Occupational Health, Safety and Environment on Site

When using a block splitter or bolster and club hammer to cut blocks, which control most directly protects the eyes?

  1. Ear defenders
  2. A high-visibility vest
  3. Safety goggles rated for impact Correct answer.
  4. A sun hat

Explanation

Cutting blocks with impact tools throws chips and fragments, so impact-rated safety goggles are the direct eye protection. Hats, ear defenders and vests protect other parts of the body or improve visibility.

Question 19Occupational Health, Safety and Environment on Site

Why must a risk assessment for a blocklaying task be reviewed when a new worker joins the crew or the method changes?

  1. Because it makes the paperwork look complete
  2. Because the law requires a new signature every day
  3. Because the hazards and the effectiveness of controls depend on who is exposed and how the work is done Correct answer.
  4. Because new workers always work faster

Explanation

A risk assessment is only valid for the circumstances it describes, so changes in people, equipment or method can introduce new hazards or undermine existing controls. Reviewing keeps the assessment live rather than a paperwork exercise.

Question 20Occupational Health, Safety and Environment on Site

Which of these is the correct way to dispose of empty cement bags and waste mortar on a Ghanaian construction site?

  1. Leave them in a pile beside the site gate
  2. Burn them at the back of the site at the end of the day
  3. Bury them in the excavation backfill
  4. Place them in designated waste skips or bins and keep the site clear for collection Correct answer.

Explanation

Waste should be segregated into designated skips or bins for proper disposal, which keeps the site safe and protects the environment. Burning releases toxic fumes, burying contaminates the ground and leaving piles creates hazards and litter.

Question 21Tools, Equipment and Materials for Blocklaying and Concreting

Which hand tool is specifically designed for laying blocks to a line and checking that each course is level and plumb as the wall rises?

  1. Club hammer
  2. Brick bolster
  3. Scutch chisel
  4. Spirit level Correct answer.

Explanation

A spirit level contains vials of liquid with an air bubble, and the bubble's position against the marked lines shows whether a surface is horizontal or vertical. Blocklayers use it continuously to check each course for level and plumb. The other tools listed are cutting or striking tools and give no reading of alignment.

Question 22Tools, Equipment and Materials for Blocklaying and Concreting

A blocklayer needs to cut a dense concrete block to a straight line. Which tool is the correct first choice for making that cut by hand?

  1. Surform rasp
  2. Masonry saw or bolster and club hammer Correct answer.
  3. Wood saw
  4. Tin snips

Explanation

Dense concrete blocks are cut with a masonry saw, or struck with a bolster held on the marked line and driven by a club hammer. These tools are made of hardened steel able to withstand impact against hard aggregate. Wood saws, snips and rasps are designed for softer materials and would be damaged.

Question 23Tools, Equipment and Materials for Blocklaying and Concreting

What is the standard nominal face size of a sandcrete block commonly produced and used in Ghana for wall construction?

  1. 450 mm × 225 mm
  2. 400 mm × 200 mm Correct answer.
  3. 300 mm × 150 mm
  4. 500 mm × 250 mm

Explanation

The common sandcrete block in Ghana is nominally 400 mm long by 200 mm high, with thicknesses such as 100 mm, 125 mm or 150 mm. The 400 × 200 face gives a modular course height of 200 mm plus the mortar joint. The other dimensions do not match the standard mould sizes used locally.

Question 24Tools, Equipment and Materials for Blocklaying and Concreting

Which material is added to a mortar mix to improve its workability and water retention so that it stays soft enough to spread under a block?

  1. Lime or plasticiser Correct answer.
  2. Bitumen
  3. Coarse aggregate
  4. Reinforcement mesh

Explanation

Lime or a chemical plasticiser is added to mortar to improve workability and water retention, helping the mix remain spreadable and adhere to the block. Coarse aggregate would turn the mix into concrete, and mesh and bitumen serve entirely different functions.

Question 25Tools, Equipment and Materials for Blocklaying and Concreting

Which piece of personal protective equipment is most important when mixing cement and sand by hand for blocklaying work?

  1. Welding goggles
  2. Safety harness
  3. Ear defenders
  4. Dust mask and gloves Correct answer.

Explanation

Hand mixing exposes the worker to cement dust and to skin contact with alkaline cement, so a dust mask and gloves are the key protection. Ear defenders, harnesses and welding goggles address hazards not present in ordinary mortar mixing.

Question 26Tools, Equipment and Materials for Blocklaying and Concreting

Which tool is used to strike or finish the mortar joint on a block wall so that it sheds water and looks neat?

  1. Pickaxe
  2. Cold chisel
  3. Pointing trowel or jointing iron Correct answer.
  4. Bricklayer's line and pins

Explanation

A pointing trowel or jointing iron is run along the joint to compact and shape the mortar, producing a weather-shedding finish. Line and pins control alignment, while a cold chisel and pickaxe are cutting and breaking tools.

Question 27Tools, Equipment and Materials for Blocklaying and Concreting

A blocklayer is setting out a rectangular building and needs to establish a true right angle at a corner. Which method uses only pegs, a line and a tape measure?

  1. Spirit-level method
  2. 3-4-5 triangle method Correct answer.
  3. Sight-line method
  4. Plumb-bob method

Explanation

The 3-4-5 method applies Pythagoras' theorem: a triangle with sides in the ratio 3:4:5 has a right angle between the two shorter sides. Measuring 3 m along one line and 4 m along the other and adjusting until the diagonal reads 5 m gives a true square corner. The other methods check level or verticality, not squareness.

Question 28Tools, Equipment and Materials for Blocklaying and Concreting

A mortar mix is specified as 1:6 cement to sand by volume. What does this ratio mean in practice?

  1. One bag of cement to six bags of coarse aggregate
  2. One part cement to six parts sand measured by volume Correct answer.
  3. One part cement to six parts water
  4. One litre of water to six kilograms of cement

Explanation

Mix ratios for mortar are stated as parts of cement to parts of fine aggregate by volume, so 1:6 means one volume of cement to six volumes of sand. Water is added separately to give a workable consistency. Coarse aggregate is not used in mortar.

Question 29Tools, Equipment and Materials for Blocklaying and Concreting

Why should sand used for blocklaying mortar be free of clay and organic matter?

  1. It weakens the bond and reduces mortar strength Correct answer.
  2. It makes the mortar set too quickly
  3. It changes the colour of the finished wall
  4. It makes the sand heavier to carry

Explanation

Clay and organic impurities coat the sand grains and prevent proper adhesion between the cement paste and the aggregate, reducing the strength and durability of the mortar. Clean, sharp sand gives a stronger bond. Weight, colour and setting speed are not the reasons for rejecting dirty sand.

Question 30Tools, Equipment and Materials for Blocklaying and Concreting

A blocklayer must cut a large number of blocks accurately and quickly on site. Which equipment gives the most consistent results?

  1. Cold chisel and mallet
  2. Scutch chisel and mallet
  3. Club hammer and bolster
  4. Mechanical masonry cutter or block-splitting machine Correct answer.

Explanation

A mechanical masonry cutter or block-splitting machine produces repeatable, accurate cuts with less waste and effort than hand tools. Hand methods such as bolster and hammer depend heavily on operator skill and give less consistent results across many blocks.

Question 31Tools, Equipment and Materials for Blocklaying and Concreting

Which of the following best describes the purpose of a plumb-bob when used on a block wall under construction?

  1. To check that the course is horizontal
  2. To test the hardness of the block
  3. To measure the length of the wall
  4. To check that the wall face is vertical Correct answer.

Explanation

A plumb-bob hangs on a string and points straight down under gravity, so comparing the string with the wall face shows whether the wall is vertical. Horizontality is checked with a spirit level, length with a tape, and hardness by other tests.

Question 32Tools, Equipment and Materials for Blocklaying and Concreting

Which of the following is the main reason for curing blockwork and concrete by keeping it moist after placing?

  1. To wash away excess cement
  2. To allow the cement to hydrate fully and gain strength Correct answer.
  3. To make the surface easier to paint
  4. To prevent the blocks from changing colour

Explanation

Cement hardens by hydration, a chemical reaction that needs water. Moist curing prevents premature drying and allows full strength development. Washing away cement, colour change and paint readiness are not the purpose of curing.

Question 33Tools, Equipment and Materials for Blocklaying and Concreting

A builder wants to produce sandcrete blocks on site. Which set of equipment is essential for the moulding operation?

  1. Block mould, vibrating table or compactor, and curing area Correct answer.
  2. Bolster, club hammer, and scutch
  3. Spirit level, plumb-bob, and line
  4. Wheelbarrow, shovel, and pickaxe

Explanation

Block production needs a mould to shape the mix, vibration or compaction to densify it, and a curing area to keep the blocks moist while they gain strength. The other sets are setting-out, cutting or general handling tools and cannot mould blocks.

Question 34Tools, Equipment and Materials for Blocklaying and Concreting

Which type of cement is commonly used for general blocklaying and concreting work in Ghana because it develops strength rapidly and is widely available?

  1. White cement
  2. High-alumina cement
  3. Ordinary Portland cement Correct answer.
  4. Sulphate-resisting cement

Explanation

Ordinary Portland cement is the general-purpose binder used for mortar and concrete in normal construction, offering good strength development and availability. High-alumina, sulphate-resisting and white cements are special-purpose products used only where their particular properties are required.

Question 35Tools, Equipment and Materials for Blocklaying and Concreting

A blocklayer is laying blocks in very hot, windy weather. What is the most appropriate action to keep the mortar workable and strong?

  1. Leave the mortar to stand uncovered before use
  2. Add more cement to every batch
  3. Mix smaller batches and use them promptly while shading the materials Correct answer.
  4. Add more water to the mortar throughout the day

Explanation

Hot, windy conditions cause rapid drying and stiffening, so mixing smaller batches, using them promptly and shading materials keeps the mortar workable without excess water. Adding water later weakens the mix, adding cement alters the ratio, and leaving mortar uncovered accelerates drying.

Question 36Tools, Equipment and Materials for Blocklaying and Concreting

Which piece of equipment is used to compact fresh concrete in a beam or column form so that air pockets are removed?

  1. Trowel
  2. Spirit level
  3. Vibrating poker Correct answer.
  4. Bolster

Explanation

A vibrating poker is inserted into fresh concrete to compact it and drive out trapped air, giving a dense, void-free element. Trowels finish surfaces, levels check alignment, and bolsters cut masonry.

Question 37Tools, Equipment and Materials for Blocklaying and Concreting

A site has sand that is damp and bulked. If the mortar is batched by volume using this damp sand without adjustment, what is the likely effect?

  1. The mix will be unaffected because dampness does not change volume
  2. The mix will contain too much water and no cement
  3. The mix will contain too much cement and be over-rich
  4. The mix will contain too little sand and be over-rich in cement Correct answer.

Explanation

Damp sand bulks, meaning a given volume contains less solid sand than dry sand would. Batching by volume without allowing for bulking therefore adds less sand than intended, making the mortar richer in cement and potentially more prone to shrinkage cracking. Moisture does not change the cement content directly.

Question 38Tools, Equipment and Materials for Blocklaying and Concreting

Why is it good practice to wet dense concrete blocks briefly before laying them in a mortar bed in hot weather?

  1. To improve the colour of the finished wall
  2. To prevent the mortar from adhering to the block
  3. To make the block heavier and more stable
  4. To stop the block absorbing water from the mortar before it can set Correct answer.

Explanation

Dry, porous blocks can suck water out of the mortar, leaving too little water for the cement to hydrate and bond properly. Brief wetting reduces this suction so the mortar cures and adheres. Weight, colour and preventing adhesion are not the aims.

Question 39Tools, Equipment and Materials for Blocklaying and Concreting

A blocklayer is choosing between a 1:4 and a 1:8 cement-to-sand mortar for a loadbearing block wall. Which statement is correct?

  1. The 1:8 mix is stronger because it contains more sand
  2. The 1:8 mix is stronger because it is more workable
  3. Both mixes have equal strength because sand is inert
  4. The 1:4 mix is stronger because it contains more cement Correct answer.

Explanation

Within normal limits, increasing the cement content raises the strength of the hardened mortar, so 1:4 is stronger than 1:8. The leaner 1:8 mix is more workable and cheaper but weaker, which matters in loadbearing walls. Sand is not inert; it forms the aggregate skeleton.

Question 40Tools, Equipment and Materials for Blocklaying and Concreting

A supervisor finds that blocks from a recent production batch are cracking and crumbling. Which combination of causes is most likely?

  1. Correct batching and prolonged moist curing
  2. Insufficient cement, dirty aggregate, and inadequate curing Correct answer.
  3. Too much cement and excessive curing
  4. Use of clean sharp sand and a vibrating table

Explanation

Weak, crumbling blocks usually result from too little cement, contaminated aggregate that prevents bonding, or failure to cure so the cement cannot hydrate. Correct batching, clean sand and proper curing and compaction all improve block quality rather than causing defects.

Question 41Setting Out, Levelling and Site Preparation

Before any trench is dug for a strip footing on a new plot, which activity must be completed so that the building sits exactly where the drawings place it?

  1. Curing the foundation concrete
  2. Erecting the scaffold standards
  3. Setting out the building lines from the site plan Correct answer.
  4. Mixing the mortar for the blockwork

Explanation

Setting out transfers the dimensions on the drawings onto the ground using pegs, profiles and lines, and every later operation depends on it being correct. Curing, scaffolding and mortar mixing all happen after excavation and are not positioning activities.

Question 42Setting Out, Levelling and Site Preparation

A datum peg on a site is marked at a reduced level of 30.000 m. A reading of 1.250 m is taken on it with a level, and the next reading on a trench bottom is 2.100 m. What is the reduced level of the trench bottom?

  1. 29.150 m Correct answer.
  2. 28.900 m
  3. 30.850 m
  4. 31.350 m

Explanation

The height of instrument is the datum level plus the backsight: 30.000 + 1.250 = 31.250 m. Subtracting the foresight of 2.100 m gives 31.250 − 2.100 = 29.150 m for the trench bottom, which is lower than the datum as expected.

Question 43Setting Out, Levelling and Site Preparation

Why are profile boards set well clear of the trench line and joined by taut lines at the correct offsets?

  1. To allow excavation without disturbing the reference lines Correct answer.
  2. To support the sides of the trench
  3. To carry the weight of the blockwork
  4. To act as a walkway for the site gang

Explanation

Profiles are set back so that digging, concrete placing and masonry work do not knock them out of position, while the lines stretched between them give a reliable reference for offsets. They are marking aids, not structural or access elements.

Question 44Setting Out, Levelling and Site Preparation

A rectangular building is to be set out with the 3-4-5 method. If a base line of 6.000 m is measured along one wall and a perpendicular is required, which pair of measurements will produce a right angle?

  1. 10.000 m along the second wall and 14.000 m on the diagonal
  2. 9.000 m along the second wall and 12.000 m on the diagonal
  3. 6.000 m along the second wall and 8.000 m on the diagonal
  4. 8.000 m along the second wall and 10.000 m on the diagonal Correct answer.

Explanation

The 3-4-5 triangle scales in proportion, so 6-8-10 is a valid multiple and gives a true right angle between the two walls. Only the option whose three lengths satisfy the Pythagorean relationship produces 90 degrees.

Question 45Setting Out, Levelling and Site Preparation

Which instrument is most suitable for transferring a level from a datum peg to many points spread across a large site?

  1. A steel tape held vertically
  2. A plumb bob on a line
  3. A dumpy or automatic level on a tripod Correct answer.
  4. A spirit level 600 mm long

Explanation

A levelling instrument with a tripod allows a backsight to the datum and foresights to many positions from one setup, giving consistent levels over long distances. The other tools transfer level only over short spans or check verticality rather than elevation.

Question 46Setting Out, Levelling and Site Preparation

During a levelling traverse, the staff readings are 1.450 m (backsight), 1.980 m, 2.320 m and 1.100 m (foresight). What is the total fall or rise between the first and last station?

  1. A rise of 0.350 m Correct answer.
  2. A fall of 0.350 m
  3. A rise of 0.670 m
  4. A fall of 0.870 m

Explanation

The change in level equals the backsight minus the foresight: 1.450 − 1.100 = 0.350 m. A smaller foresight than backsight means the last station is higher, so the result is a rise.

Question 47Setting Out, Levelling and Site Preparation

What is the main purpose of a site clearance operation before setting out begins?

  1. Marking the positions of the foundation trenches
  2. Compacting the subgrade to its final density
  3. Mixing and placing the blinding concrete
  4. Removing vegetation, topsoil and obstructions from the working area Correct answer.

Explanation

Clearance removes grass, roots, topsoil and rubbish so that lines can be seen and pegs driven reliably. Setting out, compaction and concreting are separate operations that follow or accompany clearance.

Question 48Setting Out, Levelling and Site Preparation

A builder needs to check that two long foundation lines are parallel. Which method gives a reliable check?

  1. Checking that both lines are pegged at the same spacing
  2. Measuring the length of each line separately
  3. Comparing the colour of the marking lines used
  4. Measuring the perpendicular distance between the lines at several points Correct answer.

Explanation

Parallel lines keep a constant perpendicular separation, so equal offsets measured at several positions confirm parallelism. Equal lengths or equal peg spacing say nothing about the direction of the lines.

Question 49Setting Out, Levelling and Site Preparation

Why is a temporary bench mark established on or near a construction site?

  1. To show the boundary of the client's land
  2. To provide a stable reference level for repeated height checks Correct answer.
  3. To record the depth of the excavation
  4. To mark the centre of the proposed building

Explanation

A temporary bench mark is a fixed point of known reduced level from which levels can be re-established whenever work resumes. It is a height reference, not a centre mark, depth record or boundary marker.

Question 50Setting Out, Levelling and Site Preparation

A trench is required to have its bottom at 1.200 m below ground level. The ground level is 45.600 m and the instrument height is 46.850 m. What staff reading marks the correct trench bottom?

  1. 1.150 m
  2. 1.250 m Correct answer.
  3. 2.450 m
  4. 1.350 m

Explanation

The required reduced level is 45.600 − 1.200 = 44.400 m. The staff reading is the instrument height minus that level: 46.850 − 44.400 = 2.450 m, so the correct reading is 2.450 m.