Question

6. Urban Construction Company specializes in constructing bridges. Recently they have got the contract to construct a bridge over a small body of water. It is very important to finish the construction timely as the lack of bridge is hindering the movement of people and vehicles. The management of the company determined the activates required to complete the project, the precedence relationships of the activities and the activity time estimates are as follows: Task time (weeks) Activity Activity Predecessor 10 2 7 3 1 15 4 Description Break Ground Compaction of Soil Pour Abutments Girder Placement Decking Plan Railings Installed Paint and Decor Testing 4 5 6 6 2 12 7 4,5 7 8 3,7,6 9 a) Given the following network with activity times in weeks, draw the precedence diagram and determine the earliest start and finish times, latest start and finish times using Activity Scheduling b) What will be the total project duration? c) The company is now facing problem due to the current Covid situation. They don't have access to all the raw materials and have a limited workforce. According to the directives of the government, all the workers should also practice social distancing and adapt the required protective measures for the safety. If the company still wants to maintain the actual project duration time, how should they start doing the activities? (Hints: Which task can be delayed and by how much?)

Answer 1

3 15 1 LO 4 7 8 5 6 2 7 6 12

Activity	Predecessor	Task Time	Early Start	Early Finish	Late Start	Late Finish	Float
1	-	10	0	10	0	10	0
2	-	7	0	7	6	13	6
3	1	15	10	25	10	25	0
4	1	4	10	14	14	18	4
5	2	6	7	13	12	18	5
6	2	12	7	19	13	25	6
7	4,5	7	14	21	18	25	4
8	3,7,6	9	25	34	25	34	0

The total duration of project is the duration of critical path which is 1->3->8 of duration 34 weeks

The tasks that have float can be delayed by the amoount of float. Calculated in below table and hghlighted in yellow