--- title: "Resource histogram, leveling, limited allocation, WBS" subject: "Project Engineering" chapter: 3 key: "semester_7/project_engineering:resource-terms-histogram-wbs" source: https://www.bctengineer.com/q/semester_7/project_engineering/resource-terms-histogram-wbs site: BCT Engineering --- # Resource histogram, leveling, limited allocation, WBS Project Engineering · Chapter 3: Project Planning and Scheduling - Asked in: 2070 Asar, 2+2+2+2 marks - Video: [Resource constraining example with resource histogram](https://www.youtube.com/watch?v=sy4D-dYcmT4) — Engineer4Free - Answer checked by Claude Opus 5.5 (high effort) on 2026-10-14 - Page: https://www.bctengineer.com/q/semester_7/project_engineering/resource-terms-histogram-wbs - Whole chapter: https://www.bctengineer.com/md/semester_7/project_engineering/chapter-3 ## Question Define the terms resource histogram, resource levelling, limited resource allocation and work breakdown structure. ## Short answer Resource histogram is a bar chart of resource demand per time period. Resource leveling makes demand uniform by shifting non-critical activities within float. Limited resource allocation keeps demand within a fixed maximum, possibly increasing duration. WBS is a hierarchical division of a project into manageable work packages. ## Answer #### Resource histogram A **resource histogram** is a bar chart showing the quantity of a resource (men, machines, cement) required in each time period, obtained by adding the daily needs of all activities from the schedule. It shows peaks and valleys of demand. ```text 6 |# # 5 |# # 4 |# # # 3 |# # # 2 |# # # # # # 1 |# # # # # # +------------ 1 2 3 4 5 6 day 6 6 4 2 2 2 men ``` #### Resource levelling **Resource levelling** is the rescheduling of non-critical activities within their float so that the resource demand becomes uniform and peaks are removed, keeping the project duration unchanged as far as possible. #### Limited resource allocation **Limited resource allocation** is the scheduling of activities when the available resource has a fixed maximum limit. The daily demand cannot exceed this limit; activities are delayed (by priority of least float) and the project duration may increase. #### Work breakdown structure **WBS** is a hierarchical, deliverable-oriented division of the total project into smaller manageable work packages (project - major parts - work packages), so that each can be planned, estimated, assigned and controlled. ```text Road project |-- 1 Earthwork -- 1.1 Clearing, 1.2 Cutting |-- 2 Pavement -- 2.1 Sub-base, 2.2 Base `-- 3 Drainage -- 3.1 Culverts, 3.2 Side drains ``` ## Check yourself The answer's key points as multiple-choice questions, with the correct option and why. 1. What does a resource histogram show? A. Cost of each activity B. Quantity of a resource required in each time period C. Float of each activity D. Probability of project completion Answer: B. It is a bar chart of the resource needed per period, showing peaks and valleys of demand. (Key point: Resource histogram) 2. How is a resource histogram obtained? A. By averaging the resource over the project B. By drawing the critical path only C. By adding the daily needs of all activities from the schedule D. By multiplying duration by cost Answer: C. The daily resource needs of all activities in the schedule are summed for each period. (Key point: How the histogram is built) 3. Which statement is correct? A. Levelling lengthens the project; limited allocation does not B. Limited allocation works with a fixed maximum and may increase duration; levelling keeps duration C. Both always increase duration D. Both ignore float Answer: B. Limited allocation caps daily demand and delays activities by least-float priority; levelling moves activities within float without duration change. (Key point: Levelling vs limited allocation) 4. What is a WBS? A. A list of all resources and their costs B. A bar chart of resource use C. A diagram of activity dependencies with dummies D. A hierarchical deliverable-oriented division of the project into work packages Answer: D. A WBS splits the project into major parts and work packages so each can be planned, estimated, assigned and controlled. (Key point: Work breakdown structure) ## Related in Project Engineering - [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 - [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× - [Short note: Resource leveling](https://www.bctengineer.com/question.md?key=semester_7%2Fproject_engineering%3Aresource-leveling-note) — Project Engineering, chapter 3, asked 3× - [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 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× - [Gantt chart; resource allocation and smoothing](https://www.bctengineer.com/question.md?key=semester_7%2Fproject_engineering%3Agantt-chart-resource-allocation-smoothing) — Project Engineering, chapter 3 ## Related in other subjects - [Work breakdown structure (WBS)](https://www.bctengineer.com/question.md?key=semester_7%2Fict_project_management%3Awork-breakdown-structure) — ICT Project Management, chapter 7 - [Work breakdown for frame structure quantities](https://www.bctengineer.com/question.md?key=semester_7%2Festimating_and_costing%3Awork-breakdown-quantity-frame) — Estimating and Costing, chapter 2