--- title: "Quality control in urban road construction" subject: "Project Engineering" chapter: 4 key: "semester_7/project_engineering:quality-control-urban-roads" source: https://www.bctengineer.com/q/semester_7/project_engineering/quality-control-urban-roads site: BCT Engineering --- # Quality control in urban road construction Project Engineering · Chapter 4: Project Implementation and Controlling - Asked in: 2072 Chaitra, 6 marks - Answer checked by Claude Opus 5.5 (high effort) on 2026-10-14 - Page: https://www.bctengineer.com/q/semester_7/project_engineering/quality-control-urban-roads - Whole chapter: https://www.bctengineer.com/md/semester_7/project_engineering/chapter-4 ## Question Define quality. Explain how quality can be controlled in the construction of urban roads. ## Short answer Quality is the degree to which a set of inherent characteristics of a product or service meets the specified standards, client needs and fitness for use. In urban road construction, quality is controlled at every stage: survey and setting out, compaction and field density tests, aggregate and bitumen tests, drainage first, concrete tests, surface regularity checks, supervision and documentation. ## Answer #### Quality **Quality** is the degree to which a set of inherent characteristics of a product or service meets the requirements: the specified standards, the client's needs and fitness for use. In construction, quality means the work follows the drawings, specifications and codes and is safe, durable and functional. #### Quality control in urban road construction Quality control checks every stage of the road work against the specification (for example the Standard Specification for Road and Bridge Works of the Department of Roads, Nepal) using inspection and tests. ```text Wearing course (bituminous) Binder / base course Sub-base (granular) Subgrade (compacted) ``` 1. **Survey and setting out:** check alignment, levels, width and camber before work. 2. **Subgrade:** test soil (CBR, Proctor density); compact to the required density and check by field density (sand replacement) test. 3. **Sub-base and base:** test aggregate gradation, Los Angeles abrasion value and plasticity; check layer thickness, moisture and compaction. 4. **Drainage and utilities:** make drains, culverts and utility ducts first, so that the road is not cut after paving. 5. **Bituminous work:** check bitumen grade and content, aggregate quality, mix temperature, and laying and rolling; do Marshall test and core density. 6. **Concrete work (kerb, footpath, rigid pavement):** control mix, slump, cubes and curing. 7. **Finish:** check surface regularity with straight edge, levels, cross fall and thickness. 8. **Traffic and safety management** during construction to protect workers and the public. 9. **Documentation:** daily records, test results, inspection and approval before the next layer; corrective action for failed tests. 10. **Supervision** by trained engineers, regular audits and final inspection before handing over. ## Check yourself The answer's key points as multiple-choice questions, with the correct option and why. 1. How is the subgrade checked? A. Marshall test and core density B. CBR, Proctor density and field density (sand replacement) test C. Cube test and slump test D. Los Angeles abrasion only Answer: B. Subgrade soil is tested for CBR and Proctor density and compacted, then verified with the field density test. (Key point: Subgrade control) 2. Which checks apply to bituminous layers? A. Bitumen grade and content, mix temperature, rolling, Marshall test and core density B. Slump and cube strength C. Sand replacement only D. Plasticity index only Answer: A. Bituminous work is controlled by bitumen grade/content, mix temperature, laying and rolling, Marshall test and core density. (Key point: Bituminous work) 3. Why are drains, culverts and utility ducts made first? A. To save bitumen B. So the road is not cut after paving C. To increase camber D. To avoid testing Answer: B. Laying them before paving prevents damaging the finished road later. (Key point: Drainage and utilities) 4. What must happen before the next layer is laid? A. Nothing, to save time B. Test results, inspection and approval of the previous layer, with corrective action for failed tests C. Only traffic management D. Only final handover Answer: B. Each layer is documented, tested and approved before the next layer starts; failures are corrected. (Key point: Layer-by-layer approval) ## Related in Project Engineering - [Control cycle; quality control factors](https://www.bctengineer.com/question.md?key=semester_7%2Fproject_engineering%3Acontrol-cycle-quality-control-factors) — Project Engineering, chapter 4, asked 2× - [Short note: Project quality control](https://www.bctengineer.com/question.md?key=semester_7%2Fproject_engineering%3Aquality-control-techniques-note) — Project Engineering, chapter 4, asked 2× - [Monitoring vs evaluation; quality control tools](https://www.bctengineer.com/question.md?key=semester_7%2Fproject_engineering%3Amonitoring-vs-evaluation-quality-tools) — Project Engineering, chapter 4 - [Monitoring and quality, cost, schedule control](https://www.bctengineer.com/question.md?key=semester_7%2Fproject_engineering%3Amonitoring-quality-cost-schedule-control) — Project Engineering, chapter 4 - [Closed and open control; quality cost](https://www.bctengineer.com/question.md?key=semester_7%2Fproject_engineering%3Aclosed-open-control-quality-cost) — Project Engineering, chapter 4 - [Differentiate quality control and assurance](https://www.bctengineer.com/question.md?key=semester_7%2Fproject_engineering%3Aqa-vs-qc-differentiate) — Project Engineering, chapter 4 ## Related in other subjects - [Asphalt concrete construction and quality control](https://www.bctengineer.com/question.md?key=semester_7%2Ftransportation_engineering_ii%3Aasphalt-concrete-construction) — Transportation Engineering II, chapter 3, asked 5× - [Major urban road patterns](https://www.bctengineer.com/question.md?key=semester_6%2Ftransportation_engineering_i%3Aurban-road-patterns) — Transportation Engineering I, chapter 1, asked 5× - [Urban road networks and ring road](https://www.bctengineer.com/question.md?key=semester_6%2Ftransportation_engineering_i%3Aurban-network-ring-road) — Transportation Engineering I, chapter 1, asked 2× - [Urban road cross-section elements](https://www.bctengineer.com/question.md?key=semester_6%2Ftransportation_engineering_i%3Aurban-road-cross-section) — Transportation Engineering I, chapter 3, asked 2×