WBCHSE HS Vocational Construction flashcards
WBCHSE HS Vocational Construction · Build recall with a focused review session.
32 cards. Read the term and the definition here. The deck at the top of this page is optional.
- Modular brick size
- A modular brick measures 190 × 90 × 90 mm, giving a nominal size of 200 × 100 × 100 mm after a 10 mm mortar joint.
- Initial setting time of OPC
- The time from adding water until the cement paste begins to lose plasticity; for ordinary Portland cement it must be at least 30 minutes.
- Water-cement ratio
- The ratio of mass of water to mass of cement in a mix. Lower ratios give higher strength and durability; typical RCC value is about 0.5.
- Slump test
- A workability test using a standard cone; the vertical settlement of the concrete is measured in mm. It does not measure strength.
- Curing period for OPC
- Concrete made with ordinary Portland cement must be kept moist for at least 7 days to allow hydration and develop design strength.
- Cover to reinforcement
- The clear distance from the outer concrete surface to the nearest steel bar; typically 25–30 mm for slabs and 40 mm for columns.
- English bond
- A brick bond with alternating courses of headers and stretchers. It is the strongest bond and is used for load-bearing walls.
- Flemish bond
- A bond in which each course contains alternating headers and stretchers. It gives a better appearance than English bond but is slightly weaker.
- Queen closer
- A brick cut lengthwise into two halves to complete a bond; it is placed next to the quoin header to make the course even.
- Rat-trap bond
- A hollow brick bond in which bricks are laid on edge, saving about 25% of bricks and improving thermal insulation of the wall.
- Plumb bob use
- A pointed weight hung on a string to check verticality of walls, columns, and formwork; it indicates deviation from true vertical.
- Spirit level use
- A tool with a bubble in a curved vial used to check whether a surface is horizontal or vertical; bubble centred means level.
- Needle vibrator
- A poker-type internal vibrator inserted into concrete to remove air voids; used for beams, columns, and thick sections.
- Personal protective equipment
- Safety gear worn on site, including helmet, safety shoes, goggles, gloves, and harness, to protect against injury.
- Scale 1:100
- One unit on the drawing represents 100 units on the ground; a 10 m wall is drawn 100 mm long on paper.
- Hidden line
- A dashed line on a drawing showing an edge or object not visible in the current view, such as a concealed beam or pipe.
- Centre line
- A chain line (long dash, short dash) marking the axis of symmetry of an object, such as the centre of a door or column.
- Section drawing
- A drawing showing a vertical cut through a building, revealing floor levels, foundation depth, and internal heights.
- Mortise-and-tenon joint
- A strong carpentry joint where a projecting tenon on one member fits into a rectangular mortise cut in the other member.
- Seasoning of timber
- Controlled drying of timber to reduce moisture content, preventing warping, shrinkage, and fungal decay before use.
- Plywood construction
- An odd number of thin wood veneers glued together with the grain of adjacent layers at right angles to each other.
- Dovetail joint
- An interlocking joint with fan-shaped pins and tails, used for drawer corners because it resists pulling apart.
- Gully trap
- A sanitary fitting at the junction of a house drain and the public sewer, with a water seal to prevent foul gases entering.
- MCB
- A miniature circuit breaker that automatically trips and interrupts the circuit on overload or short circuit, protecting wiring and equipment.
- Earthing
- Connecting the metal body of an electrical appliance to the ground so that fault current flows safely to earth, preventing shock.
- Self-cleansing velocity
- The minimum flow velocity in a drain, about 0.6 m/s, that keeps solid matter moving and prevents silt deposition in the pipe.
- Detailed estimate
- An item-wise estimate prepared from measured quantities and current rates, including abstract of cost, for accurate project budgeting.
- Centre line method
- A quantity method using the total centre-line length of walls multiplied by breadth and depth; half breadth is deducted at junctions.
- Rate analysis
- The process of determining the unit rate of an item from material, labour, plant, overhead, and profit components.
- Critical path
- The longest path through a CPM network; activities on it have zero float, and any delay extends the project duration.
- Break-even point
- The sales volume at which total revenue equals total cost; calculated as fixed cost divided by contribution per unit.
- Udyam registration
- The online registration for micro, small, and medium enterprises in India, giving access to government schemes and credit support.