1.Project and construction management congress  29 september-1 october.2010
ODTÜ ( Middle east technical university)  culture and congress center -Ankara
          

 

In What Detail Should be the “Work Schedule” in Construction Project Management?

 

A.Avinal
Lecturer in MBA of Yıldız Technical University with a Program on Construction Management
Founding partner  of PYO – Project Management Office Limited Company, Istanbul
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Summary

 

CPM/PERT/PCS are the methodologies used for planning and time management. At the present time there are lots of software based upon the algorithms of these systems. Such as Primavera, Microsoft Project, Suretrac, Timeline, Artemis etc..

Though working in conformity with the planning and work schedule has a major importance in the construction project management, this is the weakest point in the contracting sector. The applications of CPM methodology are very seldom, almost non-existing. In the seldom examples, it’s noted that the program mostly functions as a “Bar Chart”. The dominating reason of this result is the lack of knowledge on both what detail and what scope a work schedule should be developed and how the technology must be used in this concept.

The time-related data obtained as the result of planning, sets all data, constituting the “Baseline” of the project on a time scale. So that, we can carry out the monitoring and control phase in certain awareness with developing a procurement management plan, project budget, work orders, payment decisions, team optimization decisions.

In an international construction company culture, the expectations from a CPM software which is used as a tool for the “construction management” should be as follows:

1- Preparing the work orders to develop the discipline for monitoring and control of the production.
2- Determining the resources, developing both the procurement management plan and payment plan on a time scale.
3- Determining the required manpower and developing the team optimizations.
4- Determining the incomes and expenditures, cash flow on a time scale.
5- Preparing the payment certificates of the contractor and subcontractors.

Above mentioned functions can only be applied if the planning can be managed in a proper detail. What is meant by this proper detail? Does this proper detail depend on the decision of the planning engineer or depend on the actual content of the Project?

In this paper, it is aimed to explain, the detail level that the work schedule has to be developed, the reasons, with which modules to be integrated or data traffic to be performed between which modules and the system requirements for carrying out this detail?

 

Key words: Construction Poject Management, CPM, Planning, Work Schedule, ERP (Enterprise Resource Planning)

 

Introduction

 

Though working in conformity with the planning and work schedule has a major importance in the construction project management, this is the weakest point in the contracting sector.

The applications of CPM methodology are very seldom, almost non-existing throughout in construction sector. In the seldom examples, it’s noted that the program mostly functions as a “Bar Chart”. Generally, by force of the contracts, the planning engineers are employed  in the sites  and  it is tried to realize the requirements of the contract on the work schedule.

In general, Microsoft Project and Primavera are well known software in this matter. In the companies “Time Management” (CPM) techniques are appreciated as individual interest and capability rather than the general culture and general application of the company.

What is “a work schedule”? Why should it be done? What advantages does it offer? How can it be monitored? How can it be updated? The responses of these questions are not known and this operation is tried to be developed as an forced task required by the contract.

Our practice to develop a “work schedule” is at zero level. We employ planning engineers in sites as it is forced by the contract. The responses to what is “a work schedule”, why should it be done, what advantages does it offer, how can it be monitored and how can it be updated are not known and this operation is evaluted as an bar chart forced by the contract. Though working in conformity with the planning and work schedule has a major importance in the construction project management, this is the weakest point in the contracting sector.

The reasons are:

 

1- The lack of knowledge on both what detail and what scope a work schedule should be developed and how the technology must be used in this concept.

2-  No constrains exists  for the most of the applications.

3-  Construction Sector is alien to ERP applications and have no perception about the major advantages offered by data sharing and data transferring.

4-  The lack of informataion and education.  

 

In construction projects, what are the required productions that should be taken into consideration in developing the work schedule?

 

The most detailed table consisting the activities to be produced in a construction project is the BoQ. BoQ is the numerical and verbal expression of a construction project. In a properly detailed BoQ, the production item numbers, production definitions, quantities, production locations and unit prices are all covered.

The “work schedules” in the construction projects, are the tools calculating the time phase of the activities by using CPM and PERT algorithms with the aid of computer technologies.

This determination leads us to the reality that there should be a direct correlation between the BoQ and Work Schedule data. Every change happening in BoQ should be transferred simultaneously into the work schedule. Any change happening in the survey measurement, unit price, analysis, technical or application responsible of the production should be transferrable in the same way to the “work schedule”.

”Work schedule” is an another expression of BoQ in a different format based on timely requirements of the production and resources.

What has to be traced in a “work schedule”?   Will the execution of the productions, the period the production is executed, or the quantity executed, the time spend for the quantity to be executed, with what efficiency rates the production is executed not be monitored? Here at this point it should be clearly understood that all productions covered in a properly prepared BoQ, must also be covered in the developed work schedule. But how? As an activity or as a resource of an activity?

In BoQ, which is the numerical expression of the project, the production types are covered with their item numbers, with their survey measurements, with their unit prices and with the locations that they will be executed.

All these details should also be covered in the “work schedule” of the concerned project. The difference is in their formats. The data which takes place in the “item” detail in the BoQ, should be converted into “activity” format in the “work schedule”. The BoQ should be converted into CPM software algorithm with the aid of an ERP software. (Avinal 2009)

All productions taking place with their location, quantity and unit price in BoQ, should take place as a group named as “activity” in the “work schedule”. The productions in the BoQ, should be covered with their quantity and unit price values as the 1st level resources of the activity in the “work schedule”. In other words, we  have to have these productions as resources with their quantities and unit prices.

These are the productions taking place and to be monitored in the daily work orders should be covered in 1st.level resources of the activities in the “work schedule”. Each production covered by BoQ and “Work Schedule” should be monitored in details such as quantity, unit price, start and finish dates, execution period, technical and production responsible. Otherwise, the main expected function of a work schedule which is to develop the discipline to monitor the executed works based on work orders cannot be established.

To develop the work orders

The main function of a work schedule is to develop the discipline to monitor the executed works based on work orders derived from the work schedule. 

Work program should be the basic tool to monitor to control and to evaluate all productions based on the pre-determined time schedule criteria. In a project, this should be the first measuring criteria for the real functionality of the work schedule.

The work schedules are the tools calculating and disciplining the timely manner of the activities. In the construction projects, the activities are the production packages that should be carried out at the same time period. For instance, “reinforced concrete  works for basement floor” activity covers:

1- 250 m3 concrete

2- 30 tones  reinforcement

3- 2000 m2 formwork

 

These are the productions required to be performed together in the same time period. In fact, in the construction projects, all activities are the virtual packages of the required productions to be carried out in the same time period. If it’s required to express these virtual packages with the “analysis” concept, it will be appropriate to make a description as “production analyses” in which the productions to be performed at the same time-period and supplementary for each other, are treated as resources. In my opinion, it is appropriate to name this analysis as “activity analysis” that should take place in the analysis log of the concerned project in order to avoid the contradiction in terms,

Let’s have a look to the brief BoQ example in the Table 1 to examine the  relation between the Productions in the BoQ and the work schedule.

Table 1 BoQ Example

Item

Description

Quantity

unit

Unit price

Total

21.001

Formwork (2nd floor)

545

m2

18

9.810,00

23.001

Reinforcement (2nd floor)

142

m3

1100

156.200,00

18.001

Slab Brick (2nd floor)

227

m2

13

2.951,00

16.001

C35 Concrete (2nd floor)

77

m3

98

7.546,00

18.002

Brick wall 8,5 cm (2nd floor)

145

m2

14

2.030,00

18.003

Brick wall 19,5 cm (2nd floor)

175

m2

19

3.325,00

26.001

Screed floor covering 7-8 cm  (2nd floor)

325

m2

10

3.250,00

27.001

Plastering  (2nd floor)

750

m2

8

6.000,00

27.002

Ceiling plastering (2nd floor)

350

m2

9

3.150,00

                                                                        Total cost of the estimate

194.262,00

When we attempt to express this BoQ in the work schedule, probably the activities shown in the Table 2 will occur

Table 2 Various Activities

K2B     Floor 2nd Reinforced Concrete Production          total                        176.507.00

21.001

Formwork (2nd floor)

545

m2

18

9.810,00

23.001

Reinforcement (2nd floor)

142

m3

1100

156.200,00

18.001

Slab Brick (2nd floor)

227

m2

13

2.951,00

16.001

C35 Concrete (2nd floor)

77

m3

98

7.546,00

 
K2D     Floor 2nd Wall Production                                     total                         5.355.00

18.002

Brick wall 8,5 cm (2nd floor)

145

m2

14

2.030,00

18.003

Brick wall 19,5 cm (2nd floor)

175

m2

19

3.325,00


K2S      Floor 2nd   Screed covering and plastering           total                       12.400.00

26.001

Screed floor covering 7-8 cm  (2nd floor)

325

m2

10

3.250,00

27.001

Plastering  (2nd floor)

750

m2

8

6.000,00

27.002

Ceiling plastering (2nd floor)

350

m2

9

3.150,00

Here I would like to express that, work schedule activities can be in different numbers and combinations, but the details which can be expressed as 1stlevel resources of these activities, should express all details of the BoQ both in quantity and value. In the other words, in the construction projects, the content of the work schedule is the equivalent of the BoQ, formed in a different format.

In the above tables the total value of the three activities is equivalent of the total value of the BoQ. Quantity values of these 9 productions, generating the BoQ, formed the 1st level resources of these three activities and this is the total quantity of these 9 resources.

Rather than the activity itself, these productions, determined as the “1st Level resources” of the activity analysis should be monitored, controlled and should take place in the daily or weekly work orders.

When deciding for the duration of a activity, as it’s appeared in K2B activity in table 2, the quantity of  the item and the efficiency of the concerned  team are important. In this example, determining factor for the activity duration is probably 545 m2 Formwork.

In the K2B activity, we see the important difference. The production responsible of this activity is not 1 team but 3 teams. Concrete subcontractor, formwork subcontractor and reinforcement subcontractor. When we evaluate this activity from the point of work orders, in the 7 days of probable time period required for this activity, formwork team will work 6 days, reinforcement team will work 6 days and the concrete subcontractor will work only 1 day which is the end date of this period.

As it can be seen in this simple example, “work orders” should not be developed at the activiy level, but should be developed and given at the production level which is the 1st level resources of the activity analysis. A planning software should have suitable structure to appoint the production and technical responsible at the level of Resources. Even the most famous software in the international construction sector namely Primavera P3 does not have this feature. But Primavera P6 enables to appoint responsible person to the resource so that can be obtained at the level of work orders for the production

Other basic functions of the work schedules

 

- Determining the resources, developing both the procurement management plan and payment plan on a time scale.

- Determining the required manpower and developing the team optimizations.

- Determining the incomes and expenditures, cash flow on a time scale.

- Preparing the payment certificates of the contractor and subcontractors.

 

The material resources and manpower resources, described in the production analysis of the Project, are the production resource and  manpower needs value determining the cost of  the concerned Production. The final level resource reports of the BoQ of the concerned project gives us the quantity and the price of the all resources.

In order to develop the procurement managemet plan and to work on team optimization decisions, the duration of the activities, the time period the acitivity will be executed and the amount that will be executed at this period must be know. The work schedule responses the time-related question of the concerned activity.

Knowing the quantity, derived from the BoQ, survey measurement and analysis, based changes on a time basis makes the study on developing procurement plan and on deciding the team optimizations easy.

The payment plans are the decisions to be made in a comperative manner with the incomes after the procurement plan.

These data are the necessary data that should exist in the analysis data base, in the unit price logs, in the survey measurement module, in warehouse module, in team optimization module, procurement module, budget, cash flow module which all can be named as the memory of the company at the present technology.

In today’s technology, can it be supposed that all these data, solved in construction management ERP system, can be obtained from a CPM software?

Conclusion

As it’s seen in above examples and explanations, the major part of the data, almost the whole, to be transferred to work schedule, are the data existing in the content of an another data base. These data are the estimate data put together by the concerned people of the departments in preparation stage. The thing to be done is to transfer these data to a CPM software with the suitable format.

Realisation of such operation is usually to make the impossible possible. For instance, if we take the construction of a 5 - star hotel as an example, there exists aproxiamately 8-10 thousand activities in the work schedule of this construction and if it’s supposed that each activity consists of 3 production, its evident that more than 25 thousand resource calculation should be completed.

We can see the difficulty when we process this data manually to any CPM software or when we attempt to update in case of a probable change. However these data are the data developed in the preparatory stage of the project. These are analysed and interpreted by the project personnel. The survey measurements have been completed, analyses have been calculated, unit prices have been defined, and finally BoQ has been developed.    The only thing to be done is to transfer these data into a work schedule software or into “Primavera” by means of appropriate program in an appropriate format. Namely, to constitute “the division of labour”  between the programs.( Avinal,2009)

 

All data of the project should be interactive as it’s seen  in the content and phase on  this subject. This issuecan only be solved in ERP system structured according to the needs of the sector and by means of appropriate algorithm enable to make this transfer.

Resources

Avinal, A. (2009). “A Solution for Developing the Algorithm of Transferring Cost Estimation Data to a CPM Program via Construction Management ERP Software”, Fifth International Conference on Construction in the 21st Century (CITC-V) “Collaboration and Integration in Engineering, Management and Technology”, İstanbul, 412-419.