1 8. A DVANCED R ESOURCE M ANAGEMENT Objective: To develop new perspectives of space as resources, that will enable it to be more readily integrated with other variables into a project plan. Summary: 8.1 Introduction 8.2 Planning for Space as a Resource

2 8.1 I NTRODUCTION A primary objective of planning is to arrive at a schedule for work that satisfies all objectives, and meets all constraints: –It is relatively easy to plan a project to satisfy any one objective, or any one constraint; –Planning to satisfy many objectives and constraints is much harder; –We try to develop planning tools that will enable us to satisfy all such requirements, for example, computer-based CPM enables us to develop a plan that: satisfies all logical constraints (the activity dependencies); satisfies all the productive resource availability constraints (through multiple resource leveling); suggests ways of meeting time deadlines (by identifying the critical activities that need crashing);

3 –If an objective or constraint cannot be integrated with the other objectives or constraints within a single analysis, then: it will have to be treated independently; this may result in a compromise whereby: –the objective or constraint is not properly satisfied; or –the other objectives and constraints will no longer be satisfied. –Two factors that have not been effectively integrated in this way are: space; and costs. –Computer-based CPM does allow for cost analysis, but: traditionally this has not been done in a way that allows it to be optimized in an integrated way with the other objectives and constraints. –We can overcome this problem by treating space and costs in the same way as the productive resources: however, this is not as straight forward as for the productive resources (such as equipment and labor).

4 8.2 P LANNING FOR S PACE AS A R ESOURCE Uses of space : –storage (materials, equipment, etc): short term (temp storage of blocks while waiting to be stacked on an elevator); long term (storage of aggregate at a concrete batching plant); –performing activities: access ways (eg: a haul road); fixed location operating spaces eg: (to locate a tower crane); –locating the facility being constructed, and temporary structures: eg: the building structure, a road, or site offices, scaffolding; –space buffers; eg: safety zone around hazardous operations, or space to prevent interference between tasks; –others?

5 Types of space : –permanent space (is available from start to finish) some parts of the site; –created space (only becomes available when a certain milestone in the construction is reached): each newly constructed floor on a multi-story building; –consumed space (is available until a certain milestone is reached): the part of a site where a structure is eventually built; –created-consumed space (a combination of the previous two types of space): a floor in a building becomes available for access and storage after it has been constructed, but once the finishes have been completed (eg: carpets) then it can no longer be used for storage;

6 Measurement attributes of space: –linear vertical (side of building used for a temporary elevator); horizontal (access ways); perimeters (edge of building used to gain access such as to locate scaffolding) –area: vertical (walls used for supporting scaffolding); horizontal (floor space used for storage); –volume: warehouse where items can be stacked; Miscellaneous attributes of space: –is divisible/combinable: a space can be divided for several different uses (eg: for storage of different types of material); those same space locations could be combined at some other time to provide storage for a single large element; space locations can be combined in different ways for different tasks.

7 We have to plan the usage of space carefully: –the demand for space is obviously affected by the schedule (similar to the productive resources - equipment, labor); –the demand for space on a construction project is high, yet space is usually very scarce (similar to the productive resources); –we do not want a schedule that places two objects or activities in the same space at the same time (in other words, a space resource cannot be shared between two tasks, similar to the productive resources); –we do not want a schedule that uses space in a way that leads to unnecessary interference between tasks (this problem is NOT relevant to productive resources); –we do not want to use space in a way that leads to excessive travel distances between storage points and activity locations (this problem is NOT relevant to productive resources).

8 From the above, space is a resource that has some objectives and constraints in common with productive resources: –Q: therefore, can we treat space as a regular resource and thus use resource leveling methods to satisfy the objectives and constraints on its usage? if so, we could then integrate satisfying space usage simultaneously with the other objectives and constraints! –A: Yes, but it is NOT as straightforward as it may first appear:

9 How can we integrate planning of space into the overall planning of a project, using P3: –we can divide space into unit types, such as Perimeter ‘A1’, Access ‘B3’, and Storage ‘K32’ (resource definition); –generally, we will need one space unit type for each type of space interference that may occur; –then we can specify which activities require which space units to operate (resource assignment); –activities in conflict for space, will be assigned the same space resource unit type; –then we can specify the number of each type of space unit available (resource constraint specification); –then we could apply resource leveling to ensure that an optimal schedule is selected that does not violate the resource constraints.

10 Issues with this approach: –some space is created when a certain task is complete, while other space gets consumed when some task is started - how can P3 handle this? by using a logical dependence link that ensures that the activities requiring the space cannot start until the activity that creates the space has finished; there are some limitations to this solution, however (see lecture notes). –some space is divisible and combinable - how can P3 handle this? by careful division of space into units;