--- title: "Gantt chart; resource allocation and smoothing" subject: "Project Engineering" chapter: 3 key: "semester_7/project_engineering:gantt-chart-resource-allocation-smoothing" source: https://www.bctengineer.com/q/semester_7/project_engineering/gantt-chart-resource-allocation-smoothing site: BCT Engineering --- # Gantt chart; resource allocation and smoothing Project Engineering · Chapter 3: Project Planning and Scheduling - Asked in: 2068 Baisakh (old course), 8 marks - Video: [Resource Leveling versus Resource Smoothing - Key Project Management Concepts from the PMBOK](https://www.youtube.com/watch?v=NnYhXHcn2zs) — David McLachlan - Answer checked by Claude Opus 5.5 (high effort) on 2026-10-14 - Page: https://www.bctengineer.com/q/semester_7/project_engineering/gantt-chart-resource-allocation-smoothing - Whole chapter: https://www.bctengineer.com/md/semester_7/project_engineering/chapter-3 ## Question What is a Gantt chart? Discuss resource allocation and smoothing. ## Short answer A Gantt chart is a bar chart with each activity as a horizontal bar filled in as work progresses, so planned and actual progress are compared. Resource allocation assigns manpower, machines and materials to activities. Smoothing shifts non-critical activities within float to level demand without changing project duration or critical path; limited resource allocation may delay activities and extend duration. ## Answer #### Gantt chart A **Gantt chart** is a bar chart in which each activity is a horizontal bar on a time scale; the bar is filled in as work progresses, so that planned and actual progress are seen together. It is used for scheduling and monitoring. Example (days): A excavation (3 days, 4 men), C foundation (3 days, 2 men, after A) and B fencing and store (2 days, 2 men, independent). `=` shows work done up to the status at the end of day 3. ```text 0 2 4 6 (day) +------ A Excavation |===| C Foundation | ### B Fencing, store |== | +------ ^ status (day 3) ``` #### Resource allocation **Resource allocation** is the assignment of the available manpower, machines and materials to the activities of the schedule. The daily requirement of every activity (early start schedule) is added to get a **resource aggregation chart**, drawn as a **resource histogram**. If the demand is uneven or higher than the supply, the schedule is adjusted. Two cases occur: 1. **Resource levelling or smoothing (time-limited)** - the project duration is fixed; activities are shifted within their float to get a smooth demand. 2. **Limited resource allocation (resource-limited)** - the amount of resource available is fixed; activities are delayed, even beyond their float, so the duration may increase. #### Resource smoothing **Smoothing** is the adjustment of non-critical activities within their total float to remove peaks and valleys of the histogram without changing the project duration or the critical path. In the example the critical chain is A-C (6 days); B has a float of 4 days. Early start histogram (B on days 1-2): ```text 6 |# # 5 |# # 4 |# # # 3 |# # # 2 |# # # # # # 1 |# # # # # # +------------ 1 2 3 4 5 6 day 6 6 4 2 2 2 men ``` Peak = 6 men. Starting B on day 4 (inside its float) gives: ```text 4 |# # # # # 3 |# # # # # 2 |# # # # # # 1 |# # # # # # +------------ 1 2 3 4 5 6 day 4 4 4 4 4 2 men ``` The peak falls from 6 to 4 men; total man-days (22) and the completion time (6 days) are unchanged. Benefits: steady employment, less hiring and firing, better use of equipment. ## Check yourself The answer's key points as multiple-choice questions, with the correct option and why. 1. What is a resource histogram? A. A chart of activity dependence B. A chart of milestone dates C. A chart of the daily resource requirement added up from all activities D. A chart of cost per unit Answer: C. Adding each activity's daily need gives the aggregation drawn as a histogram. (Key point: Resource histogram) 2. What is fixed in resource levelling? A. The project duration B. The resource available C. The cost D. The number of activities Answer: A. Levelling is time-limited: activities shift within float; limited resource allocation fixes the resource instead. (Key point: Levelling vs limited) 3. How does smoothing change the schedule? A. Critical activities are delayed B. Non-critical activities move within total float without changing duration or critical path C. Project duration is increased D. Resources are added to peaks Answer: B. Smoothing uses float only, so the completion time remains the same. (Key point: Smoothing) 4. In the example, what happens when B is started on day 4? A. Peak rises to 8 men B. Completion becomes 8 days C. Total man-days change from 22 to 20 D. Peak falls from 6 to 4 men with the 6-day completion unchanged Answer: D. B has 4 days float; shifting it levels demand while total man-days (22) and duration are unchanged. (Key point: Example) ## Related in Project Engineering - [Short note: Resource allocation and smoothing](https://www.bctengineer.com/question.md?key=semester_7%2Fproject_engineering%3Aresource-allocation-smoothing-note) — Project Engineering, chapter 3, asked 4× - [Limited resource allocation and smoothing](https://www.bctengineer.com/question.md?key=semester_7%2Fproject_engineering%3Alimited-resource-allocation-smoothing-application) — Project Engineering, chapter 3 - [Resource schedule; leveling vs smoothing](https://www.bctengineer.com/question.md?key=semester_7%2Fproject_engineering%3Aresource-schedule-leveling-smoothing) — Project Engineering, chapter 3, asked 2× - [Resource leveling and smoothing](https://www.bctengineer.com/question.md?key=semester_7%2Fproject_engineering%3Aresource-leveling-smoothing-wbs-4level) — Project Engineering, chapter 3 - [Resource histogram, leveling, limited allocation, WBS](https://www.bctengineer.com/question.md?key=semester_7%2Fproject_engineering%3Aresource-terms-histogram-wbs) — Project Engineering, chapter 3 - [Gantt chart with advantages](https://www.bctengineer.com/question.md?key=semester_7%2Fproject_engineering%3Agantt-chart-draw-advantages) — Project Engineering, chapter 3 ## Related in other subjects - [Gantt chart for loading and scheduling](https://www.bctengineer.com/question.md?key=semester_6%2Findustrial_engineering_and_management%3Agantt-chart-loading-and-progress) — Industrial Engineering and Management, chapter 3 - [CPU criteria; RR Gantt and times](https://www.bctengineer.com/question.md?key=semester_6%2Foperating_system%3Acpu-criteria-rr-gantt) — Operating System, chapter 2 - [FCFS, SJF, Priority, RR Gantt; max AWT](https://www.bctengineer.com/question.md?key=semester_6%2Foperating_system%3Ascheduling-gantt-fcfs-sjf-priority-rr-q2) — Operating System, chapter 2 - [Preemptive priority and SRTF Gantt](https://www.bctengineer.com/question.md?key=semester_6%2Foperating_system%3Apreemptive-priority-srtf-gantt) — Operating System, chapter 2