How unit 1 is examined
Covers building materials (stone, brick, cement, lime, timber, paint), concrete and mortar, and the elements of a building; every topic is high weight, with the most marks in building elements and concrete.
Stones, bricks, cement, lime, timber-types, properties, test & uses
<span style="display:inline-block;padding:.16em .6em;border:1.5px solid currentColor;border-radius:999px;font-size:.68em;font-weight:700;letter-spacing:.06em;text-transform:uppercase;opacity:.75">High weight</span>
Definition. <mark>Cement is a fine powder of calcium silicates and aluminates which, mixed with water, sets and hardens into a strong binding paste; stone and brick are the natural and burnt-clay units it binds.</mark>
Diagram. <figure class="ds-fig" style="margin:1.4rem 0;overflow-x:auto"><svg xmlns="http://www.w3.org/2000/svg" id="dsfig-u1-01" viewBox="0 0 1065 194" width="1065" height="194" role="img" aria-label="Classification of stones"><style>#dsfig-u1-01 .e{stroke:#454C5A;stroke-width:1.4;fill:none}#dsfig-u1-01 .e.hi{stroke:#2340B8;stroke-width:2.6}#dsfig-u1-01 .n{fill:#FFFFFF;stroke:#16181D;stroke-width:1.4}#dsfig-u1-01 .n.hi{fill:#E3E9FC;stroke:#2340B8;stroke-width:2.2}#dsfig-u1-01 .n.rb-b{fill:#16181D;stroke:#16181D}#dsfig-u1-01 .n.rb-r{fill:#BD3227;stroke:#BD3227}#dsfig-u1-01 text{font-family:"JetBrains Mono",ui-monospace,Menlo,Consolas,monospace;font-size:13px}#dsfig-u1-01 .t{fill:#16181D;font-weight:500}#dsfig-u1-01 .t.inv{fill:#FFFFFF;font-weight:700}#dsfig-u1-01 .kd{stroke:#16181D;stroke-width:1.2}#dsfig-u1-01 .dot{fill:#16181D}#dsfig-u1-01 .ann{fill:#2340B8;font-size:11px;font-weight:700}#dsfig-u1-01 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.ptr{fill:#8FA3FF}html.dark #dsfig-u1-01 .ah{fill:#B1B7C3}html.dark #dsfig-u1-01 .ah.hi{fill:#8FA3FF}html.dark #dsfig-u1-01 .wl rect{fill:#161920;stroke:#2A2E37}html.dark #dsfig-u1-01 .wl.hi rect{fill:#8FA3FF;stroke:#8FA3FF}html.dark #dsfig-u1-01 .wl.hi .t{fill:#0F1115}</style><defs><marker id="ah1" viewBox="0 0 10 10" refX="9" refY="5" markerWidth="7" markerHeight="7" orient="auto-start-reverse"><path class="ah" d="M0,1 L9,5 L0,9 z"/></marker><marker id="ahh1" viewBox="0 0 10 10" refX="9" refY="5" markerWidth="7" markerHeight="7" orient="auto-start-reverse"><path class="ah hi" d="M0,1 L9,5 L0,9 z"/></marker></defs><line class="e" x1="511.8" y1="37" x2="165.8" y2="101"/><line class="e" x1="511.8" y1="37" x2="516.3" y2="101"/><line class="e" x1="511.8" y1="37" x2="857.8" y2="101"/><line class="e" x1="165.8" y1="101" x2="51.5" y2="165"/><line class="e" x1="165.8" y1="101" x2="158" y2="165"/><line class="e" x1="165.8" y1="101" x2="280" y2="165"/><line class="e" x1="516.3" y1="101" x2="398" y2="165"/><line class="e" x1="516.3" y1="101" x2="520" y2="165"/><line class="e" x1="516.3" y1="101" x2="634.5" y2="165"/><line class="e" x1="857.8" y1="101" x2="737.5" y2="165"/><line class="e" x1="857.8" y1="101" x2="856" y2="165"/><line class="e" x1="857.8" y1="101" x2="978" y2="165"/><rect class="n" x="478.3" y="22" width="67" height="30" rx="8"/><text class="t" x="511.8" y="37" dy=".35em" text-anchor="middle">Stones</text><rect class="n" x="116.8" y="86" width="98" height="30" rx="8"/><text class="t" x="165.8" y="101" dy=".35em" text-anchor="middle">Geological</text><rect class="n" x="14" y="150" width="75" height="30" rx="8"/><text class="t" x="51.5" y="165" dy=".35em" text-anchor="middle">Igneous</text><rect class="n" x="105" y="150" width="106" height="30" rx="8"/><text class="t" x="158" y="165" dy=".35em" text-anchor="middle">Sedimentary</text><rect class="n" x="227" y="150" width="106" height="30" rx="8"/><text class="t" x="280" y="165" dy=".35em" text-anchor="middle">Metamorphic</text><rect class="n" x="474.8" y="86" width="83" height="30" rx="8"/><text class="t" x="516.3" y="101" dy=".35em" text-anchor="middle">Physical</text><rect class="n" x="349" y="150" width="98" height="30" rx="8"/><text class="t" x="398" y="165" dy=".35em" text-anchor="middle">Stratified</text><rect class="n" x="463" y="150" width="114" height="30" rx="8"/><text class="t" x="520" y="165" dy=".35em" text-anchor="middle">Unstratified</text><rect class="n" x="593" y="150" width="83" height="30" rx="8"/><text class="t" x="634.5" y="165" dy=".35em" text-anchor="middle">Foliated</text><rect class="n" x="816.3" y="86" width="83" height="30" rx="8"/><text class="t" x="857.8" y="101" dy=".35em" text-anchor="middle">Chemical</text><rect class="n" x="692" y="150" width="91" height="30" rx="8"/><text class="t" x="737.5" y="165" dy=".35em" text-anchor="middle">Siliceous</text><rect class="n" x="799" y="150" width="114" height="30" rx="8"/><text class="t" x="856" y="165" dy=".35em" text-anchor="middle">Argillaceous</text><rect class="n" x="929" y="150" width="98" height="30" rx="8"/><text class="t" x="978" y="165" dy=".35em" text-anchor="middle">Calcareous</text></svg><figcaption style="font-size:.82em;opacity:.72;margin-top:.45rem">Classification of stones</figcaption></figure>
Key points.
- Geologically stones are igneous (granite, basalt), sedimentary (sandstone, limestone) or metamorphic (marble, slate, quartzite); physically they are stratified, unstratified or foliated; chemically siliceous, argillaceous or calcareous.
- A good building stone is strong, durable, hard, tough, of specific gravity above 2.6, uniform in appearance, fire resistant and low in water absorption.
- Stone tests are crushing strength, water absorption, impact, attrition (abrasion) and acid test; common stones are granite (foundations, columns), sandstone (walls), limestone, marble (flooring), slate (roofing) and basalt/trap (aggregate).
- Cement composition by oxide: lime CaO 60-67% gives strength but excess causes expansion and cracking; silica SiO$_2$ 17-25% gives strength; alumina Al$_2$O$_3$ 3-8% gives quick setting; iron oxide 0.5-6% gives colour and hardness; magnesia MgO 0.1-4% gives colour but excess causes unsoundness; sulphur trioxide with gypsum retards flash setting.
- These oxides combine on burning into Bogue's compounds: $C_3S$ (early strength), $C_2S$ (later strength), $C_3A$ (flash set, heat) and $C_4AF$.
- Setting time is measured on the Vicat apparatus: initial set is not less than 30 min (paste starts losing plasticity) and final set is not more than 600 min (paste fully hard).
- Field tests of cement: colour should be uniform greenish-grey, it should feel smooth and cool when the hand is plunged in, and a pinch should float briefly on water. Field tests of sand: rub between palms for silt and organic stain, and shake in a measuring cylinder of salt water to read the silt layer (should be under 8%); bulking is checked by volume change when damp.
- Laboratory tests: brick compressive strength (frog-filled, 24 h soaked, crushed in a compression machine; minimum 3.5 N/mm$^2$ for common bricks) and water absorption (not over 20%); cement fineness (sieve 90 micron, residue below 10%) and standard consistency (Vicat plunger stops 5-7 mm from base; about 26-33% water).
- Efflorescence is a whitish powdery deposit of soluble salts left on masonry when water evaporates. Law of machine is $P = mW + C$, a straight-line relation between effort $P$ and load $W$.
- Plastering covers the whole wall surface with mortar; pointing finishes only the exposed joints. Lime is obtained by burning limestone (quicklime) and slaking; timber is classified as exogenous (softwood, hardwood) and used for doors, windows and shuttering.
- Paint has a base (white lead, zinc oxide), vehicle (linseed oil), pigment (colour), thinner (turpentine) and drier (litharge). Desired properties are good covering power, easy application, weather resistance, durability and uniform drying. Types are oil, enamel, emulsion, distemper, cement, bituminous and aluminium paint.
Answer frame. Open with the definition; draw the classification tree for stone; develop composition oxide by oxide with its function and the excess effect, then Bogue's compounds; for test questions choose two tests and give apparatus, procedure and limit; close with the use.
Pitfall: Quoting only percentages for cement composition loses the marks for the function of each oxide.
Asked: [7 marks] (Nov 2022) Narrate the classification of stone used in construction industry. Asked: [7 marks] (Dec 2023) Define any two field tests conducted on cement and sand. Asked: [7 marks] (Dec 2023) What is the composition of cement? Explain in detail. Asked: [7 marks] (Dec 2023) Define any four: law of machine; initial and final setting time of cement; efflorescence; curing of concrete; plastering and pointing. Asked: [7 marks] (Jun 2023) Define any two laboratory tests conducted on bricks and cement. Asked: [7 marks] (Jun 2025) Characteristics of stones, their methods of testing, and names of stones used in building work. Asked: [7 marks] (Jun 2025) Constituents, desirable properties and types of paints.
Laboratory tests: concrete and mortar, workability, strength, nominal proportion, preparation, compaction, curing
<span style="display:inline-block;padding:.16em .6em;border:1.5px solid currentColor;border-radius:999px;font-size:.68em;font-weight:700;letter-spacing:.06em;text-transform:uppercase;opacity:.75">High weight</span>
Definition. <mark>Workability is the ease with which fresh concrete can be mixed, transported, placed, compacted and finished without segregation.</mark>
Key points.
- Factors affecting workability are water content (more water raises workability), aggregate size and shape (rounded need less water than angular), grading and surface texture (smooth, well graded is better), admixtures (plasticizers), and temperature and time (hot weather and delay stiffen the mix).
- Segregation is separation of coarse aggregate from mortar; bleeding is upward movement of water to the surface of fresh concrete; proportion is the ratio cement : sand : aggregate, e.g. M15 is 1:2:4 and M20 is 1:1.5:3.
- Slump test measures workability: fill the 300 mm cone in 4 layers of 25 blows, lift it and measure the subsidence; 25-75 mm suits ordinary reinforced work.
- Compressive strength test: cast 150 mm cubes, cure 28 days, crush; strength = load / area.
- Physical properties are workability, compressive and tensile strength, elasticity, creep, shrinkage, durability and permeability; chemical properties are hydration of cement (C-S-H gel, heat), alkali-aggregate reaction, sulphate attack, carbonation and resistance to acids and chlorides.
- Nominal mix uses fixed volumetric proportions from the code (M5 to M20) without trials; design mix is fixed by laboratory trials for a target strength.
- Preparation of concrete: batching by weight or volume, mixing by hand or machine, transporting, placing, compacting, finishing, curing.
- Compaction removes trapped air by hand tamping or vibrators (needle, surface); poor compaction leaves honeycombing and loses strength.
- Curing keeps concrete moist for hydration by ponding, wet burlap or spraying, membrane, or steam curing; keep it up for at least 7 days (10 days for blended cement).
- Mortar is a paste of cement or lime, sand and water that binds masonry units and levels courses.
| Basis | Nominal mix | Design mix |
|---|---|---|
| Proportion | Fixed by code | Found by lab trials |
| Batching | Volume | Weight |
| Strength grades | M20 and lower | M25 and higher |
| Economy | Wastes cement | More economical |
| Use | Minor works | Structural works |
Example. Mortar for 1 m$^3$ brickwork in 1:4 mix. Given: wet mortar 0.30 m$^3$; dry volume = 1.3 x 0.30 = 0.39 m$^3$. Cement = 0.39 / 5 = 0.078 m$^3$ = 0.078 x 1440 / 50 = 2.25 bags; sand = 0.39 x 4/5 = 0.312 m$^3$. Answer: 2.25 bags cement and 0.31 m$^3$ sand. Cube strength: load 675 kN on 150 x 150 mm gives $675000/22500 =$ 30 N/mm$^2$.
Answer frame. For workability open with the definition, list six factors with one reason each, close with the slump test; for two tests give slump then cube, each with apparatus, procedure, result; for nominal versus design draw the table then close with the use.
Pitfall: Curing is not drying; wetting must continue after setting or hydration stops.
Asked: [7 marks] (Jun 2022, Dec 2023) Define workability of concrete and discuss the factors that affect it. Asked: [7 marks] (Nov 2022, Dec 2024) Write about physical and chemical properties of concrete. Asked: [7 marks] (Jun 2022) Discuss any two laboratory tests conducted on concrete. Asked: [3 marks] (Jun 2022) Curing. Asked: [7 marks] (Dec 2023) Explain nominal and design mix concrete in detail. Asked: [7 marks] (Jun 2023) Define workability, segregation, bleeding, proportion in concrete. Asked: [7 marks] (Dec 2024) Briefly talk about the concrete preparation procedure. Asked: [7 marks] (Dec 2024) Briefly discuss the compaction and curing process. Asked: [7 marks] (Jun 2025) What is mortar? Describe the estimation of mortar requirement.
Building elements: foundations, footings, masonry, plaster, floors, roofs, doors, windows, lintels, stairs
<span style="display:inline-block;padding:.16em .6em;border:1.5px solid currentColor;border-radius:999px;font-size:.68em;font-weight:700;letter-spacing:.06em;text-transform:uppercase;opacity:.75">High weight</span>
Definition. <mark>A foundation is the lowest part of a structure that transfers the load safely to the soil, distributes it within the bearing capacity, and prevents overturning and differential settlement.</mark>
Diagram. <figure class="ds-fig" style="margin:1.4rem 0;overflow-x:auto"><svg xmlns="http://www.w3.org/2000/svg" id="dsfig-u1-02" viewBox="0 0 656 194" width="656" height="194" role="img" aria-label="Types of foundation; shallow means depth Df not more than width B"><style>#dsfig-u1-02 .e{stroke:#454C5A;stroke-width:1.4;fill:none}#dsfig-u1-02 .e.hi{stroke:#2340B8;stroke-width:2.6}#dsfig-u1-02 .n{fill:#FFFFFF;stroke:#16181D;stroke-width:1.4}#dsfig-u1-02 .n.hi{fill:#E3E9FC;stroke:#2340B8;stroke-width:2.2}#dsfig-u1-02 .n.rb-b{fill:#16181D;stroke:#16181D}#dsfig-u1-02 .n.rb-r{fill:#BD3227;stroke:#BD3227}#dsfig-u1-02 text{font-family:"JetBrains Mono",ui-monospace,Menlo,Consolas,monospace;font-size:13px}#dsfig-u1-02 .t{fill:#16181D;font-weight:500}#dsfig-u1-02 .t.inv{fill:#FFFFFF;font-weight:700}#dsfig-u1-02 .kd{stroke:#16181D;stroke-width:1.2}#dsfig-u1-02 .dot{fill:#16181D}#dsfig-u1-02 .ann{fill:#2340B8;font-size:11px;font-weight:700}#dsfig-u1-02 .lbl{fill:#6F7787;font-family:system-ui,-apple-system,sans-serif;font-size:12px;font-weight:700}#dsfig-u1-02 .ptr{fill:#2340B8;font-size:12px;font-weight:700}#dsfig-u1-02 .ah{fill:#454C5A}#dsfig-u1-02 .ah.hi{fill:#2340B8}#dsfig-u1-02 .wl rect{fill:#FFFFFF;stroke:#DCE0E7}#dsfig-u1-02 .wl .t{font-size:12px;font-weight:700}#dsfig-u1-02 .wl.hi rect{fill:#2340B8;stroke:#2340B8}#dsfig-u1-02 .wl.hi .t{fill:#FFFFFF}html.dark #dsfig-u1-02 .e{stroke:#B1B7C3}html.dark #dsfig-u1-02 .e.hi{stroke:#8FA3FF}html.dark #dsfig-u1-02 .n{fill:#161920;stroke:#E6E8ED}html.dark #dsfig-u1-02 .n.hi{fill:#1E2748;stroke:#8FA3FF}html.dark #dsfig-u1-02 .n.rb-b{fill:#E6E8ED;stroke:#E6E8ED}html.dark #dsfig-u1-02 .n.rb-r{fill:#FF7E71;stroke:#FF7E71}html.dark #dsfig-u1-02 .t{fill:#E6E8ED}html.dark #dsfig-u1-02 .t.inv{fill:#0F1115}html.dark #dsfig-u1-02 .kd{stroke:#E6E8ED}html.dark #dsfig-u1-02 .dot{fill:#E6E8ED}html.dark #dsfig-u1-02 .ann{fill:#8FA3FF}html.dark #dsfig-u1-02 .lbl{fill:#858D9C}html.dark #dsfig-u1-02 .ptr{fill:#8FA3FF}html.dark #dsfig-u1-02 .ah{fill:#B1B7C3}html.dark #dsfig-u1-02 .ah.hi{fill:#8FA3FF}html.dark #dsfig-u1-02 .wl rect{fill:#161920;stroke:#2A2E37}html.dark #dsfig-u1-02 .wl.hi rect{fill:#8FA3FF;stroke:#8FA3FF}html.dark #dsfig-u1-02 .wl.hi .t{fill:#0F1115}</style><defs><marker id="ah2" viewBox="0 0 10 10" refX="9" refY="5" markerWidth="7" markerHeight="7" orient="auto-start-reverse"><path class="ah" d="M0,1 L9,5 L0,9 z"/></marker><marker id="ahh2" viewBox="0 0 10 10" refX="9" refY="5" markerWidth="7" markerHeight="7" orient="auto-start-reverse"><path class="ah hi" d="M0,1 L9,5 L0,9 z"/></marker></defs><line class="e" x1="372.9" y1="37" x2="221.8" y2="101"/><line class="e" x1="372.9" y1="37" x2="524" y2="101"/><line class="e" x1="221.8" y1="101" x2="55.5" y2="165"/><line class="e" x1="221.8" y1="101" x2="154.5" y2="165"/><line class="e" x1="221.8" y1="101" x2="241.5" y2="165"/><line class="e" x1="221.8" y1="101" x2="316.5" y2="165"/><line class="e" x1="221.8" y1="101" x2="388" y2="165"/><line class="e" x1="524" y1="101" x2="456" y2="165"/><line class="e" x1="524" y1="101" x2="524" y2="165"/><line class="e" x1="524" y1="101" x2="592" y2="165"/><rect class="n" x="323.9" y="22" width="98" height="30" rx="8"/><text class="t" x="372.9" y="37" dy=".35em" text-anchor="middle">Foundation</text><rect class="n" x="184.3" y="86" width="75" height="30" rx="8"/><text class="t" x="221.8" y="101" dy=".35em" text-anchor="middle">Shallow</text><rect class="n" x="14" y="150" width="83" height="30" rx="8"/><text class="t" x="55.5" y="165" dy=".35em" text-anchor="middle">Isolated</text><rect class="n" x="113" y="150" width="83" height="30" rx="8"/><text class="t" x="154.5" y="165" dy=".35em" text-anchor="middle">Combined</text><rect class="n" x="212" y="150" width="59" height="30" rx="8"/><text class="t" x="241.5" y="165" dy=".35em" text-anchor="middle">Strip</text><rect class="n" x="287" y="150" width="59" height="30" rx="8"/><text class="t" x="316.5" y="165" dy=".35em" text-anchor="middle">Strap</text><rect class="n" x="362" y="150" width="52" height="30" rx="8"/><text class="t" x="388" y="165" dy=".35em" text-anchor="middle">Raft</text><rect class="n" x="498" y="86" width="52" height="30" rx="8"/><text class="t" x="524" y="101" dy=".35em" text-anchor="middle">Deep</text><rect class="n" x="430" y="150" width="52" height="30" rx="8"/><text class="t" x="456" y="165" dy=".35em" text-anchor="middle">Pile</text><rect class="n" x="498" y="150" width="52" height="30" rx="8"/><text class="t" x="524" y="165" dy=".35em" text-anchor="middle">Pier</text><rect class="n" x="566" y="150" width="52" height="30" rx="8"/><text class="t" x="592" y="165" dy=".35em" text-anchor="middle">Well</text></svg><figcaption style="font-size:.82em;opacity:.72;margin-top:.45rem">Types of foundation; shallow means depth Df not more than width B</figcaption></figure>
Key points.
- Shallow foundations have $D_f \le B$: isolated footing under one column, combined under two, strip under a wall, strap joining two footings by a beam, raft (mat) under the whole building.
- Deep foundations are pile, pier and caisson (well); RCC footings are isolated (pad, stepped, sloped), combined (rectangular, trapezoidal) and strap (cantilever).
- A bond is the arrangement of bricks that avoids continuous vertical joints: English has alternate courses of headers and stretchers with a queen closer after the quoin header; Flemish has headers and stretchers alternating in every course; stretcher bond suits half-brick walls and header bond curved walls.
- Principles of brick masonry: soak bricks, keep courses level and plumb with spirit level and plumb bob, stagger vertical joints, keep 10 mm joints filled, raise at most 1.5 m a day, cure 1-2 weeks.
- Stone masonry is rubble (uncoursed, coursed, random, dry) or ashlar (fine, rough tooled, chamfered).
- Plastering covers rough walls with lime or cement mortar for a smooth, durable finish; pointing finishes exposed joints as flush, struck, V-grooved, keyed or recessed.
- Floors are mud, brick, cement concrete, terrazzo, mosaic, marble; roofs are flat, pitched (sloped) or shell and must be watertight, insulating and strong.
- Doors by construction are battened and ledged, panelled, glazed; by operation hinged, revolving, sliding, swing, rolling shutter, collapsible. Windows are casement, sash, sliding, clerestory, bay, skylight, dormer, louvered.
- A lintel is a beam over an opening in masonry, of wood, stone, brick or RCC; RCC is best for wide spans.
- Stairs: straight, dog-legged, open-well, quarter-turn, bifurcated, spiral.
- Stages of construction: site investigation, excavation, foundation, plinth beam, superstructure, lintel and slab, plastering, flooring, doors and windows, finishing; materials are cement, sand, aggregate, brick, steel, timber and paint.
| Stair type | Feature |
|---|---|
| Dog-legged | Two flights, opposite directions, no well |
| Open-well | Flights around a central open space |
| Spiral | Steps wind round a central post |
| Quarter-turn | Turns 90 degrees at a landing |
| Basis | Plastering |
| --- | --- |
| Area | Whole surface |
| Purpose | Smooth finish |
Answer frame. Foundation: open with the definition, draw the tree and a strip footing section, develop shallow then deep types, close with suitability. Doors and windows: list by construction and operation, then selection by light, ventilation and security. Stairs: define, draw a dog-legged plan, describe each type.
Asked: [7 marks] (Jun 2022) Different types of footing and types of brick bond. Asked: [7 marks] (Nov 2022) Different types of staircase with a neat sketch. Asked: [7 marks] (Dec 2023) Short notes: shallow foundation. Asked: [7 marks] (Dec 2023, Jun 2025) Types of doors and windows; describe various types of windows. Asked: [7 marks] (Jun 2023, Dec 2024) Purpose of foundation and its types; types of RCC footing. Asked: [7 marks] (Jun 2023) Stages of building construction and building materials. Asked: [7 marks] (Jun 2023) Discuss plastering and pointing. Asked: [7 marks] (Jun 2023) Types of bonds in brick masonry. Asked: [7 marks] (Jun 2025) General principles in brick masonry construction. Asked: [7 marks] (Jun 2025) Types of stone masonry with sketches. Asked: [3 marks] (Jun 2022) Roofs.
Last-minute revision
- Cement oxides: CaO 60-67%, SiO$_2$ 17-25%, Al$_2$O$_3$ 3-8%; Bogue's compounds C3S, C2S, C3A, C4AF.
- Initial setting time at least 30 min; final at most 600 min.
- Common brick strength at least 3.5 N/mm$^2$; water absorption at most 20%.
- M15 is 1:2:4 and M20 is 1:1.5:3; nominal mix is by volume.
- Cube 150 mm, 28 days, strength = load / area.
- Wet mortar 0.25-0.30 m$^3$ per m$^3$ brickwork; dry = 1.25-1.3 times.
- Shallow foundation: $D_f \le B$.
- Brick joint 10 mm; raise 1.5 m per day.
- Law of machine: $P = mW + C$.
Memory hooks
- CSA-G: Lime, Silica, Alumina, Gypsum give strength, strength, quick set, slow set.
- Bleeding is water going up, segregation is stones going down.
- English bond: alternate courses; Flemish: alternate in every course.
Coverage checklist
- Stones, bricks, cement, lime, timber-types, properties, test & uses: stone classification, field tests, cement composition, definitions, lab tests, stone characteristics, paints.
- laboratory tests concrete and mortar Materials: Workability, Strength properties of Concrete, Nominal proportion of Concrete preparation of concrete, compaction, curing: workability, properties, tests, curing, nominal vs design mix, definitions, preparation, compaction, mortar.
- Elements of Building Construction, Foundations conventional spread footings, RCC footings, brick masonry walls, plastering and pointing, floors, roofs, Doors, windows, lintels, staircases – types and their suitability: footings and bonds, stairs, shallow foundation, doors and windows, foundation types, stages, plastering, bonds, principles, stone masonry, roofs.