---
title: "Objectives of investigation for hill road"
subject: "Engineering Geology I"
chapter: 1
key: "semester_3/engineering_geology_i:objectives-of-investigation-for-hill"
source: https://www.bctengineer.com/q/semester_3/engineering_geology_i/objectives-of-investigation-for-hill
site: BCT Engineering
---

# Objectives of investigation for hill road

Engineering Geology I · Chapter 1: Geology and Civil Engineering

- Asked in: 2059 Chaitra (old course), 2+6 marks
- Video: [Unit 8 | Site Investigation ⛏️ | Engineering Geology | In Nepali](https://www.youtube.com/watch?v=4tOIJ-3fUFE) — BYK Learning
- Answer checked by Claude Opus 5.5 (high effort) on 2026-10-14
- Page: https://www.bctengineer.com/q/semester_3/engineering_geology_i/objectives-of-investigation-for-hill
- Whole chapter: https://www.bctengineer.com/md/semester_3/engineering_geology_i/chapter-1

## Question

Define engineering geology and list out the major objectives of the engineering geological investigation for a hill-road project.

## Short answer

Engineering geology applies geological principles to civil engineering for safe, economical, and environmentally harmonious works. For a hill-road project, major objectives include selecting a stable alignment avoiding landslides and faults, identifying rock and soil types and structures, assessing slope stability and groundwater, locating construction materials, evaluating hazards, and designing stabilization and drainage measures.

## Answer

**Engineering geology** is the application of geological principles and data to civil engineering so that works are planned, designed and built safely, economically and in harmony with the environment.

#### Major objectives of investigation for a hill road
1. **Selection of the best alignment**: compare alternative routes and choose the most stable, shortest and economical one, avoiding active landslides, fault zones and unstable slopes.
2. **Identification of rock and soil types** along the route, their strength and weathering, to decide cut slope angles and excavation methods (manual, ripping or blasting).
3. **Study of geological structures**: dip and strike of beds and joints relative to the road cut; whether discontinuities dip out of the slope (risk of planar or wedge failure).
4. **Landslide and slope stability assessment**: mapping existing and potential slides, rockfall and debris-flow areas; deciding treatment.
5. **Groundwater and drainage**: locating springs, seepage and gullies; planning side drains, culverts and subsurface drainage.
6. **Foundation conditions for bridges, culverts and retaining walls**: depth to bedrock, bearing capacity and scour.
7. **River training**: studying river erosion, flood levels and bank stability where the road runs along rivers.
8. **Material survey**: finding quarries for aggregate, borrow areas for fill and sources of sand.
9. **Hazard evaluation**: seismic zone, active faults, debris flows, glacial lake outburst floods in high areas.
10. **Design of stabilisation measures**: retaining walls, breast walls, gabions, bioengineering, anchors.
11. **Environmental protection**: minimising slope disturbance and planning safe disposal of spoil.
12. **Cost estimation**: reliable quantities of rock and soil excavation, and of protection works.

These objectives are met through desk study, aerial photograph interpretation, engineering geological mapping along the alignment, test pits and boreholes at critical sites, and geophysical profiling.

## Check yourself

The answer's key points as multiple-choice questions, with the correct option and why.

1. The first objective for a hill road is to:
   A. Choose the steepest route
   B. Select the most stable, economical alignment avoiding landslides and faults
   C. Ignore existing slides
   D. Select routes only along rivers
   Answer: B. Alignment choice avoids hazards. (Key point: Alignment)

2. Why study dip and strike relative to the road cut?
   A. To find mineral colour
   B. To choose bridge paint
   C. Discontinuities dipping out of the slope risk planar or wedge failure
   D. To count joints for fun
   Answer: C. Out-dipping discontinuities allow sliding. (Key point: Structure vs cut)

3. Locating springs and seepage helps to:
   A. Increase slope water pressure
   B. Avoid drainage design
   C. Choose aggregate
   D. Plan side drains, culverts and subsurface drainage
   Answer: D. Water control is essential for slope stability. (Key point: Groundwater)

4. The material survey aims to find:
   A. Quarries, borrow areas and sand sources
   B. Active faults only
   C. Foundation rock for dams
   D. Seismic zones
   Answer: A. Road building needs aggregate, fill and sand. (Key point: Materials)

## Related in Engineering Geology I

- [Engineering geological map and site investigation](https://www.bctengineer.com/question.md?key=semester_3%2Fengineering_geology_i%3Aengineering-geological-map-and-site) — Engineering Geology I, chapter 1, asked 3×
- [Site investigation for road construction](https://www.bctengineer.com/question.md?key=semester_3%2Fengineering_geology_i%3Asite-investigation-for-road-construction) — Engineering Geology I, chapter 1
- [Scope and importance of geology in civil engineering](https://www.bctengineer.com/question.md?key=semester_3%2Fengineering_geology_i%3Ascope-and-importance-of-geology) — Engineering Geology I, chapter 1, asked 24×
- [Define engineering geology; scope and importance](https://www.bctengineer.com/question.md?key=semester_3%2Fengineering_geology_i%3Adefine-engineering-geology-scope-and) — Engineering Geology I, chapter 1, asked 24×
- [Engineering geological problems in tectonic divisions](https://www.bctengineer.com/question.md?key=semester_3%2Fengineering_geology_i%3Aengineering-geological-problems-in-tectonic) — Engineering Geology I, chapter 7, asked 2×
- [Engineering geology versus geology; disciplines](https://www.bctengineer.com/question.md?key=semester_3%2Fengineering_geology_i%3Aengineering-geology-versus-geology-disciplines) — Engineering Geology I, chapter 1, asked 2×

## Related in other subjects

- [Geological investigation of tunnel and road](https://www.bctengineer.com/question.md?key=semester_4%2Fengineering_geology_ii%3Atunnel-road-investigation) — Engineering Geology II, chapter 4
- [Geology in road alignment selection](https://www.bctengineer.com/question.md?key=semester_4%2Fengineering_geology_ii%3Aroad-alignment-geology) — Engineering Geology II, chapter 4, asked 5×
- [Road, dam and foundation site geology](https://www.bctengineer.com/question.md?key=semester_4%2Fengineering_geology_ii%3Aroad-dam-building-bridge-foundation) — Engineering Geology II, chapter 4
- [Engineering geological problems of Siwalik zone](https://www.bctengineer.com/question.md?key=semester_4%2Fengineering_geology_ii%3Asiwalik-problems) — Engineering Geology II, chapter 2, asked 4×