B.Tech. I-Semester (Main/Back) Exam - 2025

Building plans include:

• Site Plan: Shows property line limits and surrounding layout.
• Floor Plan: Shows layout of rooms, doors, and windows from above.
• Elevation Plan: Shows exterior front, side, or rear view of the building.
• Sectional Plan: Internal vertical cross-section showing structural heights.

Bearing Capacity is the maximum load-carrying capacity per unit area of soil without causing shear failure or excessive settlement of the foundation structure.

Orientation refers to positioning a building's axis relative to the sun, wind direction, and surroundings. Proper orientation maximizes natural ventilation, daylighting, and thermal comfort while reducing energy consumption.

• Plinth Area: Built-up covered area measured at the basement level inclusive of wall thickness.
• Floor Area: Total area of all floors inside the outer walls (Plinth Area minus area of external walls).
• Carpet Area: Net usable floor space inside rooms excluding walls, corridors, balconies, and staircases.

1. Working from whole to part: Main control points are established first with high precision to prevent accumulation of measurement errors.
2. Locating new points by at least two independent measurements: Points are plotted using distance/angle from known reference points.

• Combines Electronic Distance Meter (EDM) and digital theodolite in one unit.
• Provides high precision for distance, height, and angle measurements.
• Automated digital data storage allows direct export to CAD mapping software.

Ozone layer depletion is the gradual thinning of the stratospheric ozone shield caused by chemical pollutants like Chlorofluorocarbons (CFCs), allowing harmful ultraviolet radiation to reach Earth.

• Metric Chain: Available in 20m or 30m lengths with links every 20cm.
• Gunter's Chain: 66 feet long (100 links), used for measuring land in acres.
• Engineer's Chain: 100 feet long (100 links).
• Revenue Chain: 33 feet long (16 links), traditionally used in land revenue surveys.

Building Byelaws are legal rules framed by local municipal authorities to regulate structural design, construction standards, setback lines, safety features, and zoning limits for organized urban development.

The four primary modes are: 1. Roadways: Provides door-to-door accessibility.
2. Railways: Ideal for heavy bulk transport across long distances.
3. Airways: Fast long-distance transit.
4. Waterways: Most economical mode for international bulk freight.

Traffic signs are categorized into three major groups:

• Stop Sign (Mandatory/Regulatory): Octagonal shape; indicates vehicles must halt before proceeding.
• Give Way (Regulatory): Inverted triangle; instructs drivers to grant right-of-way to main road traffic.
• Pedestrian Crossing (Cautionary): Triangular border with pedestrian symbol; warns drivers of crossing zones.
• Speed Limit (Mandatory): Circular symbol showing maximum permissible speed in km/h.
• Hospital Ahead (Informatory): Blue rectangular sign displaying a bed/plus symbol; indicates medical services nearby.

A building is divided into two primary sub-structures:

• Substructure (Foundation): Part below ground level that distributes total structural loads directly onto soil.
• Superstructure: Part above ground level including:
  • Plinth: Prevents moisture entry into the ground floor.
  • Walls & Columns: Vertical members carrying structural loads.
  • Slab/Roof: Provides shelter and upper floor support.
  • Lintels & Chajjas: Protect openings against weather forces.

Water supply sources are split into:

• Surface Water Sources: Lakes, rivers, streams, impounded reservoirs, and ponds. Easily accessible but requires thorough chemical treatment.
• Sub-surface (Ground) Water Sources: Open wells, tube wells, artesian wells, and springs. Naturally filtered by soil strata, requiring basic disinfection before use.

Disinfection kills pathogenic bacteria to ensure safe drinking water:

• Chlorination: Addition of liquid chlorine or bleaching powder (most common method).
• Boiling: Kills microorganisms by heat (suitable for domestic scale).
• Ozonation: Uses ozone gas (O₃) as a powerful disinfectant without leaving residual tastes.
• UV Radiation: Passes ultraviolet rays through water to destroy bacterial DNA.

Sources of Errors:

1. Instrumental Errors: Sluggish magnetic needle, non-vertical pivot, or inaccurate graduation line alignment.
2. Personal Errors: Inaccurate leveling of compass, improper sighting, or incorrect reading entry.
3. Natural / Local Attraction: Magnetic distortion caused by nearby iron structures, steel cables, or power lines.

Precautions:

• Keep iron objects (keys, buckles) away from the compass while taking readings.
• Check both Fore Bearing (FB) and Back Bearing (BB) to identify local attraction (FB - BB = 180°).

• Height of Instrument (H.I.) Method:
  First find Plane of Collimation: H.I. = R.L. + B.S.
  Then compute Reduced Level: R.L. = H.I. - I.S. or F.S.
  Advantage: Faster for large staff reading entries.
• Rise and Fall Method:
  Compares consecutive staff readings to determine height differences.
  Difference = Previous Reading - Present Reading (Positive = Rise, Negative = Fall).
  Advantage: Full arithmetic check on intermediate stations.

A standard wastewater treatment process includes three sequential phases:

1. Primary Treatment: Physical separation using screening bars and grit chambers to remove floating solids and sediment.
2. Secondary Treatment: Biological oxidation using Activated Sludge Processes or Trickling Filters to break down dissolved organic matter.
3. Tertiary Treatment: Chemical disinfection (e.g., chlorination) to remove residual nutrients and pathogens prior to disposal.

The Hydrological Cycle is the continuous circulation of water between the atmosphere, land, and oceans driven by solar energy. Key stages include Evaporation, Transpiration, Condensation, Precipitation, Infiltration, and Runoff.

Effects of Environmental Pollution:

• Acid Rain: Emissions of SO₂ and NO_x pollute raindrops, damaging forest cover and aquatic life.
• Global Warming: Increased temperatures alter precipitation frequency, resulting in unseasonal droughts and flash floods.
• Groundwater Contamination: Industrial runoff prevents soil infiltration of clean water.

• Profile Levelling: Executed along the center line of a proposed alignment (roads, railways, pipelines) to obtain a longitudinal profile section of the ground surface. Staff readings are recorded at set distance intervals along the route.
• Cross-Sectioning: Executed perpendicular to the main center line at defined intervals to determine lateral ground slopes. Useful for calculating earthwork excavation and embankment fill volumes.

• (a) Screening: Passes raw water through coarse or fine screens to capture large floating objects like debris and branches.
• (b) Sedimentation: Slows water flow velocity in tanks to settle suspended solids naturally under gravity.
• (c) Filtration: Passes water through sand beds to trap fine colloidal impurities and microorganisms.
• (d) Unit Operation: Individual physical separation step (e.g., mixing, settling, filtration) within a water treatment plant sequence.

Given Field Data:

Side	Fore Bearing (FB)	Back Bearing (BB)	Difference (FB ~ BB)
AB	80°10'	259°00'	178°50' (Local attraction)
BC	120°20'	310°50'	190°30' (Local attraction)
CD	170°50'	350°50'	180°00' (Free from Local Attraction)
DE	230°10'	49°30'	180°40' (Local attraction)
EA	310°20'	130°15'	180°05' (Local attraction)

Step 1: Interior Angle Calculation
Interior Angle = Back Bearing of Previous Line - Fore Bearing of Next Line

• Angle A = BB of EA - FB of AB = 130°15' - 80°10' = 50°05'
• Angle B = BB of AB - FB of BC = 259°00' - 120°20' = 138°40'
• Angle C = BB of BC - FB of CD = 310°50' - 170°50' = 140°00'
• Angle D = BB of CD - FB of DE = 350°50' - 230°10' = 120°40'
• Angle E = BB of DE - FB of EA = (49°30' + 360°) - 310°20' = 99°10'

Step 2: Check & Error Correction
Sum of measured interior angles:
Sum of Angles = 50°05' + 138°40' + 140°00' + 120°40' + 99°10' = 548°35'

Theoretical sum for 5-sided closed polygon (N=5):
Theoretical Sum = (2N - 4) × 90° = (2(5) - 4) × 90° = 540°00'

Total Observational Error: +8°35' (Correction = -8°35' distributed equally among all 5 interior angles, i.e., -1°43' per angle).