DDA JE Civil flashcards

32 cards. Read the term and the definition here. The deck at the top of this page is optional.

Bulking of sand

Increase in the volume of moist fine aggregate due to surface moisture films separating particles; measured as a percentage, commonly 20–30% for fine sand, and corrected during volume batching.

Abram's law

Empirical relation stating concrete strength is inversely proportional to the water-cement ratio for a given set of materials and curing conditions; lower w/c gives higher compressive strength.

Zero air void line

The theoretical compaction curve on a dry-density versus water-content plot where soil contains no air; no compaction curve can lie above it, and it marks the maximum density possible.

Terzaghi bearing capacity formula

For a strip footing, ultimate bearing capacity equals cNc + γDfNq + 0.5γBNγ, where c is cohesion, γ unit weight, Df depth, B width, and N factors depend on the friction angle.

Rise and fall method

Levelling reduction where rise equals backsight minus foresight; each reduced level is found by adding rises and subtracting falls, with an arithmetic check on the differences.

Point of contraflexure

Location in a beam where the bending moment changes sign, so the bending moment is zero there; common in overhanging beams and continuous beams under combined loading.

Slump test

Workability test using a standard cone; the vertical settlement of the concrete after the cone is lifted is the slump, classified as true, shear, or collapse slump.

Standard Proctor test

Laboratory compaction test using a 2.6 kg rammer in three layers; gives the optimum moisture content and maximum dry density for a soil under light compaction energy.

Effective stress principle

Total stress in a saturated soil equals effective stress plus pore water pressure; only effective stress controls shear strength, compressibility, and settlement of the soil skeleton.

Letter position value

In coding-decoding, letters are numbered A=1 through Z=26; shifts, sums, and reversals (A with Z, B with Y) are tested using these positions to decode patterns.

Syllogism reversal rule

A statement 'Some A are B' can always be reversed to 'Some B are A', while 'All A are B' cannot be reversed unless the reverse is separately stated.

Clock hand angle formula

The angle between hour and minute hands equals the absolute value of 30H minus 5.5M degrees, where H is the hour and M the minutes past the hour.

Odd days in calendar

Days left over after dividing total days by seven; an ordinary year has one odd day, a leap year two, and a century has five odd days except a 400-year multiple with six.

Direction displacement method

Resolve each movement into north-south and east-west components, sum them, then take the square root of the sum of squares to get the straight-line distance from start.

Blood relation tree

A diagram of family members with gender symbols and connecting lines for marriage and descent, used to trace relationships without confusing generations or in-laws.

Seating arrangement anchor

Fixing one person's position and facing direction first, then applying left-right rules relative to that facing, which resolves the remaining positions in circular or linear puzzles.

Number series second difference

When first differences between consecutive terms are not constant, compute differences of those differences; a constant second difference indicates a quadratic pattern in the series.

Article 32

Right to Constitutional Remedies; allows a person to move the Supreme Court directly for enforcement of fundamental rights through writs such as habeas corpus and mandamus.

Fundamental Duties

Part IVA, Article 51A, added by the 42nd Amendment in 1976 on the Swaran Singh Committee's recommendation; eleven duties are listed and they are non-justiciable.

Money bill definition

A bill dealing only with taxation, borrowing, or the Consolidated Fund; certified by the Lok Sabha Speaker under Article 110 and introduced only in the Lok Sabha.

Black cotton soil

Expansive soil formed from Deccan trap basalt, rich in montmorillonite clay; swells on wetting and shrinks on drying, causing severe volume change and low bearing capacity.

Indus Waters Treaty

1960 treaty between India and Pakistan dividing the Indus system; India got unrestricted use of eastern rivers Ravi, Beas, and Sutlej, while western rivers were largely allocated to Pakistan.

NITI Aayog

National Institution for Transforming India, set up on 1 January 2015 as a policy think tank replacing the Planning Commission; the Prime Minister chairs it and it has no fund allocation role.

Western Ghats hotspot

A mountain range along India's west coast recognised as a global biodiversity hotspot, with high endemism and heavy monsoon rainfall feeding major peninsular river systems.

Article 61

The constitutional provision for impeachment of the President for violation of the Constitution, requiring a charge by one House and a two-thirds special majority in both Houses.

Present perfect tense

Formed with has or have plus the past participle; it describes a past action linked to the present, such as an experience or an action just completed with current relevance.

Between and among

Between is used for two persons or things and among for more than two; both are prepositions, and between can also show a relationship between separate items.

Since versus for

Since is used with a specific point in time, such as since 2010, while for is used with a duration, such as for five years, in present perfect constructions.

Passive voice formation

The object becomes the subject, the verb becomes a form of be plus the past participle, and the original subject follows by; only transitive verbs can be made passive.

Altruist

A person who is selflessly concerned for the well-being of others, often at personal cost; the noun form is altruism and the adjective is altruistic.

At the eleventh hour

An idiom meaning at the last possible moment or just before a deadline, referring to a very late intervention rather than the literal eleventh hour of a day.

Articles with vowel sounds

Use an before words beginning with a vowel sound, including silent h words like hour, and a before consonant sounds, including university and one, which start with consonant sounds.