1ChristianHOFSTADLER2010 Construction Management

Analysis of Situation

Objective

Calculation Mode 1:

Deterministic

Approach

Calculation Mode 3:

Monte Carlo Method

Application:

High-Rise Building

Conclusion

Palisade Risk Conference in LondonSource:

CASE STUDY

Hofstadler

Univ.-Doz.Dipl.-Ing.Dr.techn.

Christian HofstadlerAssociate Professor

Institute of Construction Management and Economics

Graz University of Technology, Austria

hofstadler@tugraz.at

2ChristianHOFSTADLER2010 Construction Management

Analysis of Situation

Objective

Calculation Mode 1:

Deterministic

Approach

Calculation Mode 3:

Monte Carlo Method

Application:

High-Rise Building

Conclusion

Palisade Risk Conference in LondonSource:

CASE STUDY

Hofstadler

Construction time is of crucial importance when it comes to utilizing the

production factors in an effective and efficient way.

Construction periods that are too short usually result in higher cost, poorer quality

and a larger number of disputes.

This presentation sets out to demonstrate the calculation of construction time and

cost whilst considering key construction management parameters.

Beyond a simple, deterministic method, other options for calculation

are shown that rely on probability calculus.

The approaches described to determine construction time and cost are illustrated

by a building project example.

3ChristianHOFSTADLER2010 Construction Management

Analysis of Situation

Objective

Calculation Mode 1:

Deterministic

Approach

Calculation Mode 3:

Monte Carlo Method

Application:

High-Rise Building

Conclusion

Palisade Risk Conference in LondonSource:

Production Factors

Production Factors

Work

Material

Equipment

Elementary

Production Factors

Dispositive

Production Factors

Organisation

Direction

Planning

Monitoring

Control Circuit

Construction

Time/Cost

4ChristianHOFSTADLER2010 Construction Management

Analysis of Situation

Objective

Calculation Mode 1:

Deterministic

Approach

Calculation Mode 3:

Monte Carlo Method

Application:

High-Rise Building

Conclusion

Palisade Risk Conference in LondonSource:

Productivity as a Function of Time

Pro

du

ctiv

ity [%

]

Construction time [d]

100 %

Adequate

Construction time

No go

Hofstadler

5ChristianHOFSTADLER2010 Construction Management

Analysis of Situation

Objective

Calculation Mode 1:

Deterministic

Approach

Calculation Mode 3:

Monte Carlo Method

Application:

High-Rise Building

Conclusion

Palisade Risk Conference in LondonSource:

Duration: From the Rough Planning to Detailed Planning

Hofstadler

Construction Time/

Costs

Rough Planning Detailed Planning

Entire constructionComponent

Assembly

Component

Assembly per Floor

Components/

Production units

6ChristianHOFSTADLER2010 Construction Management

Analysis of Situation

Objective

Calculation Mode 1:

Deterministic

Approach

Calculation Mode 3:

Monte Carlo Method

Application:

High-Rise Building

Conclusion

Palisade Risk Conference in LondonSource:

Duration: From the Rough Planning to Detailed Planning

Accuracy

Processing effort

Certainty

+

_

+

_

+

_

Hofstadler

Construction Time/

Costs

Rough Planning Detailed Planning

Entire constructionComponent

Assembly

Component

Assembly per Floor

Components/

Production units

7ChristianHOFSTADLER2010 Construction Management

Analysis of Situation

Objective

Calculation Mode 1:

Deterministic

Approach

Calculation Mode 3:

Monte Carlo Method

Application:

High-Rise Building

Conclusion

Palisade Risk Conference in LondonSource:

Calculation of Construction Time and Costs

Calculation

Construction Time/Costs

Calculation Mode 1 Calculation Mode 2 Calculation Mode 3

Deterministic ApproachSimplified Stochastic

Approach

Application of Monte

Carlo Method

Hofstadler

8ChristianHOFSTADLER2010 Construction Management

Analysis of Situation

Objective

Calculation Mode 1:

Deterministic

Approach

Calculation Mode 3:

Monte Carlo Method

Application:

High-Rise Building

Conclusion

Palisade Risk Conference in LondonSource:

Calculation of Construction Time and Costs

Calculation

Construction Time/Costs

Calculation Mode 1 Calculation Mode 2 Calculation Mode 3

Deterministic ApproachSimplified Stochastic

Approach

Application of Monte

Carlo Method

Hofstadler

9ChristianHOFSTADLER2010 Construction Management

Analysis of Situation

Objective

Calculation Mode 1:

Deterministic

Approach

Calculation Mode 3:

Monte Carlo Method

Application:

High-Rise Building

Conclusion

Palisade Risk Conference in LondonSource:

Calculation of Construction Time: Deterministic Approach

Hofstadler

10ChristianHOFSTADLER2010 Construction Management

Analysis of Situation

Objective

Calculation Mode 1:

Deterministic

Approach

Calculation Mode 3:

Monte Carlo Method

Application:

High-Rise Building

Conclusion

Palisade Risk Conference in LondonSource:

Calculation Equation: Rough planning

Calculation of Construction Time for Reinforced Concrete Works

Hofstadler

Maximum number of workers [wh/hr].....................MAXRCWW ,

Average number of workers [wh/hr].....................ARCWW ,

Total duration of reinforced concrete works [d].....................TOTD

Duration of the starting period of reinforced concrete works [d].....................SPD

Duration of the main construction time of reinforced concrete works [d].....................MCT

D

Duration of the final stage of reinforced concrete works [d].....................FSD

11ChristianHOFSTADLER2010 Construction Management

Analysis of Situation

Objective

Calculation Mode 1:

Deterministic

Approach

Calculation Mode 3:

Monte Carlo Method

Application:

High-Rise Building

Conclusion

Palisade Risk Conference in LondonSource:

%1001

,

,

,

RCWT

RCWA

RCWRCW

CBURCW

BU

TRC

WTW

QD

Calculation Equation: Rough planning

Calculation of Construction Time for Reinforced Concrete Works

MAXRCWRCWMINRCW DDD ,,

Hofstadler

12ChristianHOFSTADLER2010 Construction Management

Analysis of Situation

Objective

Calculation Mode 1:

Deterministic

Approach

Calculation Mode 3:

Monte Carlo Method

Application:

High-Rise Building

Conclusion

Palisade Risk Conference in LondonSource:

%1001

,

,,,,,

,

RCWT

CWABDARWABDAFWA

RCWRCW

CBURCW

BU

RCRRRCFRRC

WTW

QD

Calculation Equation: Rough planning

Calculation of Construction Time for Reinforced Concrete Works

Hofstadler

MAXRCWRCWMINRCW DDD ,,

13ChristianHOFSTADLER2010 Construction Management

Analysis of Situation

Objective

Calculation Mode 1:

Deterministic

Approach

Calculation Mode 3:

Monte Carlo Method

Application:

High-Rise Building

Conclusion

Palisade Risk Conference in LondonSource:

FWARC ,

RWARC ,

CWARC ,

Average labor consumption rate for

. formwork-related activities [wh/m]

. Average formwork ratio for the entire building [m/m]

. Average labor consumption rate for reinforcement works [wh/t]

. Average reinforcement ratio for the entire building [t/m]

. Average labor consumption rate for concrete works [wh/m]

BDAFR ,

BDARR ,

. Average daily working time [hr/d]RCWWT

. Average number of workers [wh/hr]RCWW

. Concrete quantity [m]CQ

. Duration of the reinforced concrete works incl. Buffer [d]BURCWD ,

Calculation Equation: Calculation of Construction Time

Hofstadler

%1001

,

,,,,,

,

RCWT

CWABDARWABDAFWA

RCWRCW

CBURCW

BU

RCRRRCFRRC

WTW

QD

RCWTBU , . Buffer for construction time [%]

14ChristianHOFSTADLER2010 Construction Management

Analysis of Situation

Objective

Calculation Mode 1:

Deterministic

Approach

Calculation Mode 3:

Monte Carlo Method

Application:

High-Rise Building

Conclusion

Palisade Risk Conference in LondonSource:

Calculation of Cost of Production: Deterministic Approach

Hofstadler

15ChristianHOFSTADLER2010 Construction Management

Analysis of Situation

Objective

Calculation Mode 1:

Deterministic

Approach

Calculation Mode 3:

Monte Carlo Method

Application:

High-Rise Building

Conclusion

Palisade Risk Conference in LondonSource:

Calculation Equation: Rough planning

Calculation of Cost of Production for Reinforced Concrete Works

Hofstadler

RCWEMAc ,,

. Average average wage for reinforced concrete works [/wh]RCWAWA ,

. Concrete quantity [m]CQ

. Duration of the reinforced concrete works incl. Buffer [d]BURCWC ,

Hofstadler

%1001

%1001

,

,,,,,

RCWCOHDRCWEMARCWARCWACBURCW

BUMUcWATCRQCP

Average total labor consumption rate for

. reinforced concrete works [wh/m]RCWATCR ,

. Mark-up for overhead costs [%]OHDMU

. Buffer for costs [%]RCWCBU ,

Average equipment and materials costs for

. reinforced concrete works [/m]

16ChristianHOFSTADLER2010 Construction Management

Analysis of Situation

Objective

Calculation Mode 1:

Deterministic

Approach

Calculation Mode 3:

Monte Carlo Method

Application:

High-Rise Building

Conclusion

Palisade Risk Conference in LondonSource:

Calculation Equation: Rough planning

Calculation of Cost of Production for Reinforced Concrete Works

HofstadlerHofstadler

%1001

%1001

,

,,,,,

RCWCOHDRCWEMARCWARCWACBURCW

BUMUcWATCRQCP

MAXRCWRCWMINRCW CPCPCP ,,

17ChristianHOFSTADLER2010 Construction Management

Analysis of Situation

Objective

Calculation Mode 1:

Deterministic

Approach

Calculation Mode 3:

Monte Carlo Method

Application:

High-Rise Building

Conclusion

Palisade Risk Conference in LondonSource:

Average total labor consumption rate for

. reinforced concrete works [wh/m]RCWATCR ,

FWARC ,

RWARC ,

CWARC ,

Average labor consumption rate for

. formwork-related activities [wh/m]

. Average formwork ratio for the entire building [m/m]

. Average labor consumption rate for reinforcement works [wh/t]

. Average reinforcement ratio for the entire building [t/m]

. Average labor consumption rate for concrete works [wh/m]

BDAFR ,

BDARR ,

Hofstadler

CWABDARWABDAFWARCWA RCRRRCFRRCTCR ,,,,,,

Calculation Equation: Rough planning

18ChristianHOFSTADLER2010 Construction Management

Analysis of Situation

Objective

Calculation Mode 1:

Deterministic

Approach

Calculation Mode 3:

Monte Carlo Method

Application:

High-Rise Building

Conclusion

Palisade Risk Conference in LondonSource:

RCWEMAc ,,

FWEMAc ,,

RWEMAc ,,

CWEMAc ,,

. Average formwork ratio for the entire building [m/m]

. Average reinforcement ratio for the entire building [t/m]

BDAFR ,

BDARR ,

Hofstadler

CWEMABDARWEMABDAFWEMARCWEMA cRRcFRcc ,,,,,,,,,,

Calculation Equation: Rough planning

Average equipment and materials costs for

. reinforced concrete works [/m]

Average equipment and materials costs for

. formwork works [/m]

Average equipment and materials costs for

. reinforcement works [/t]

Average equipment and materials costs for

. concrete works [/m]

19ChristianHOFSTADLER2010 Construction Management

Analysis of Situation

Objective

Calculation Mode 1:

Deterministic

Approach

Calculation Mode 3:

Monte Carlo Method

Application:

High-Rise Building

Conclusion

Palisade Risk Conference in LondonSource: Hofstadler

Calculation of Construction Time: Application of Monte Carlo Method

20ChristianHOFSTADLER2010 Construction Management

Analysis of Situation

Objective

Calculation Mode 1:

Deterministic

Approach

Calculation Mode 3:

Monte Carlo Method

Application:

High-Rise Building

Conclusion

Palisade Risk Conference in LondonSource:

Influences on Production Rate

Labor productivityProduction

Rate

General construction

site conditions

Number of workers

Availability

Construction

method

Number of

equipment

General operating

conditions

Specific structural

conditions

Influences of the

construction method

Daily working time

Working time

scheme

Construction

method

Type of

construction projectLocation of the

construction project

Familiarization

Specific structure

conditions

General operating

conditions

General construction

site conditions

Practice

Influences of the

construction method

Work space

Staff qualification

Composition of the

working group

Disruptive

influences

External

Internal

Working time

regulations

Hofstadler

*RCFW FRBD RCRW RRBD RCCW+ * +

Selection of distribution functions and input of individual values

TRCRCW

Calculation with @RISK Monte Carlo Method

Presenting the Results as Probability Distribution

22ChristianHOFSTADLER2010 Construction Management

Analysis of Situation

Objective

Calculation Mode 1:

Deterministic

Approach

Calculation Mode 3:

Monte Carlo Method

Application:

High-Rise Building

Conclusion

Palisade Risk Conference in LondonSource:

0

1,000

2,000

3,000

4,000

5,000

6,000

7,000

8,000

9,000

10,000

0102030405060708090100110120130140

DRCW= 40 d

DRCW= 45 d

DRCW= 50 d

DRCW= 55 d

DRCW= 60 d

DRCW= 65 d

DRCW= 70 d

DRCW= 75 d

DRCW= 80 d

DRCW= 85 d

DRCW= 90 d

DRCW= 95 d

DRCW= 100 d

DRCW= 105 d

DRCW= 110 d

0

1,000

2,000

3,000

4,000

5,000

6,000

7,000

8,000

9,000

10,000

5.00 5.25 5.50 5.75 6.00 6.25 6.50 6.75 7.00 7.25 7.50 7.75 8.00 8.25 8.50

TWH= 10,000 wh TWH= 12,500 wh TWH= 15,000 wh TWH= 17,500 whTWH= 20,000 wh TWH= 22,500 wh TWH= 25,000 wh TWH= 27,500 whTWH= 30,000 wh TWH= 32,500 wh TWH= 35,000 wh TWH= 37,500 whTWH= 40,000 wh TWH= 42,500 wh TWH= 45,000 wh TWH= 47,500 whTWH= 50,000 wh TWH= 52,500 wh TWH= 55,000 wh TWH= 57,500 wh

0.0000.5001.0001.5002.0002.5003.0003.5004.0004.5005.0005.5006.0006.5007.0007.5008.0008.5009.0009.50010.00010.50011.00011.50012.000

0102030405060708090100110120130140

DWT = 8 hr/d

DWT = 9 hr/d

DWT = 10 hr/d

DWT = 11 hr/d

DWT = 12 hr/d

DWT = 13 hr/d

DWT = 14 hr/d

DWT = 15 hr/d

DWT = 16 hr/d

0.0000.5001.0001.5002.0002.5003.0003.5004.0004.5005.0005.5006.0006.5007.0007.5008.0008.5009.0009.500

10.00010.50011.00011.50012.000

5.00 5.25 5.50 5.75 6.00 6.25 6.50 6.75 7.00 7.25 7.50 7.75 8.00 8.25 8.50

W = 10 wh/hr W = 15 wh/hr W = 20 wh/hr

W = 25 wh/hr W = 30 wh/hr W = 35 wh/hr

W = 40 wh/hr W = 45 wh/hr W = 50 wh/hr

W = 55 wh/hr W = 60 wh/hr W = 65 wh/hr

W = 70 wh/hr W = 75 wh/hr W = 80 wh/hr

Total labor productivity [wh/m]Daily output [m/d]

Ho

url

y o

utp

ut [m

/h

r]C

on

cre

te q

ua

nti

ty [m

]

ChristianHOFSTADLER

III

III IV

Interaction diagram for reinforced concrete works

Use within Interaction Diagrams

107 d

91 d

38,500 Std33,000 Std

Hofstadler

Total consumption rate [wh/m]

*RCFW FRBD RCRW RRBD RCCWWRCW WTRCW

DRCW, BU

+ * +

Selection of distribution functions and input of individual values

QC BUT,RCW

TRCRCW

PRRCW,ML

DRCW

Calculation with @RISK Monte Carlo Method

Presenting the Results as Probability Distribution

24ChristianHOFSTADLER2010 Construction Management

Analysis of Situation

Objective

Calculation Mode 1:

Deterministic

Approach

Calculation Mode 3:

Monte Carlo Method

Application:

High-Rise Building

Conclusion

Palisade Risk Conference in LondonSource: Hofstadler

Calculation of Cost of Production: Application of Monte Carlo Method

*RCFW FRBD RCRW RRBD RCCW+ * +

Selection of distribution functions and input of individual values

*cEM,FW FRBD cEM,RW RRBD cEM,CW+ * +

cEM,RCW*TRCRCW * QCWARCW * QC

DCLC,RCW + DCEM,RCW

CPRCW,BU

DCRCW MUOHD+

CPRCW BURCW+

26ChristianHOFSTADLER2010 Construction Management

Analysis of Situation

Objective

Calculation Mode 1:

Deterministic

Approach

Calculation Mode 3:

Monte Carlo Method

Application:

High-Rise Building

Conclusion

Palisade Risk Conference in LondonSource:

Application

Hofstadler

27ChristianHOFSTADLER2010 Construction Management

Analysis of Situation

Objective

Calculation Mode 1:

Deterministic

Approach

Calculation Mode 3:

Monte Carlo Method

Application:

High-Rise Building

Conclusion

Palisade Risk Conference in LondonSource:

High-Rise Building Project - Key Details

Hofstadler

Sectional view

28ChristianHOFSTADLER2010 Construction Management

Analysis of Situation

Objective

Calculation Mode 1:

Deterministic

Approach

Calculation Mode 3:

Monte Carlo Method

Application:

High-Rise Building

Conclusion

Palisade Risk Conference in LondonSource:

High-Rise Building Project - Key Details

Hofstadler

Floor plan

29ChristianHOFSTADLER2010 Construction Management

Analysis of Situation

Objective

Calculation Mode 1:

Deterministic

Approach

Calculation Mode 3:

Monte Carlo Method

Application:

High-Rise Building

Conclusion

Palisade Risk Conference in LondonSource:

[m] [%] [t] [%] [m] [%]1 2 3 4 5 6 7

Ground plate 225 0.46 431 23.28 3,080 24.39

Walls 5,553 11.26 103 5.56 739 5.85

Columns 3,598 7.30 89 4.81 270 2.14

Shafts 15,554 31.54 266 14.37 1,902 15.06

Slabs 24,386 49.45 962 51.97 6,638 52.56

49,316 100 1,851 100 12,629 100

ComponentsForming area

Reinforcement

quantityConcrete quantity

High-Rise Building Project - Key Details

Hofstadler

Office building: quantity determination

30ChristianHOFSTADLER2010 Construction Management

Analysis of Situation

Objective

Calculation Mode 1:

Deterministic

Approach

Calculation Mode 3:

Monte Carlo Method

Application:

High-Rise Building

Conclusion

Palisade Risk Conference in LondonSource:

Average labor consumption rate - formwork works 0.60 wh/m 0.65 wh/m 0.90 wh/m

Average formwork ratio for the entire building 3.60 m/m 3.90 m/m 4.00 m/m

Average labor consumption rate - reinforcement works 7.00 wh/t 8.00 wh/t 10.00 wh/t

Average reinforcement ratio for the entire building 140.00 kg/m 150.00 kg/m 160.00 kg/m

Average labor consumption rate - concrete works 0.42 wh/m 0.45 wh/m 0.60 wh/m

Maximum number of workers 36.00 wh/hr 37.00 wh/hr 40.00 wh/hr

Proportion of the average number of workers 75.00 % 80.00 % 88.00 %

Daily working time 7.00 hr/d 8.50 hr/d 10.00 hr/d

Concrete Quanity 12,000 m 12,629 m 13,000 m

Buffer 7.50 % 10.00 % 13.00 %

MIN EXP MAX

High-Rise Building Project - Key Details

Input values to calculate the construction time

Hofstadler

Labor productivityProduction

Rate

General construction

site conditions

Number of workers

Availability

Construction

method

Number of

equipment

General operating

conditions

Specific structural

conditions

Influences of the

construction method

Daily working time

Working time

scheme

Construction

method

Type of

construction projectLocation of the

construction project

Familiarization

Specific structure

conditions

General operating

conditions

General construction

site conditions

Practice

Influences of the

construction method

Work space

Staff qualification

Composition of the

working group

Disruptive

influences

External

Internal

Working time

regulations

31ChristianHOFSTADLER2010 Construction Management

Analysis of Situation

Objective

Calculation Mode 1:

Deterministic

Approach

Calculation Mode 3:

Monte Carlo Method

Application:

High-Rise Building

Conclusion

Palisade Risk Conference in LondonSource:

d

mwhmttwhmmmwh

dhrhrwh

mD BURCW 231

%100

%101

/45.0/15.0/8/9.3/65.0

/5.88.0/37

629,12,

Hofstadler

Calculation of Construction Time: Calculation Mode 1

%1001

,

,,,,,

,

RCWT

CWABDARWABDAFWA

RCWRCW

CBURCW

BU

RCRRRCFRRC

WTW

QD

Average labor consumption rate - formwork works 0.60 wh/m 0.65 wh/m 0.90 wh/m

Average formwork ratio for the entire building 3.60 m/m 3.90 m/m 4.00 m/m

Average labor consumption rate - reinforcement works 7.00 wh/t 8.00 wh/t 10.00 wh/t

Average reinforcement ratio for the entire building 140.00 kg/m 150.00 kg/m 160.00 kg/m

Average labor consumption rate - concrete works 0.42 wh/m 0.45 wh/m 0.60 wh/m

Maximum number of workers 36.00 wh/hr 37.00 wh/hr 40.00 wh/hr

Proportion of the average number of workers 75.00 % 80.00 % 88.00 %

Daily working time 7.00 hr/d 8.50 hr/d 10.00 hr/d

Concrete Quanity 12,000 m 12,629 m 13,000 m

Buffer 7.50 % 10.00 % 13.00 %

MIN EXP MAX

32ChristianHOFSTADLER2010 Construction Management

Analysis of Situation

Objective

Calculation Mode 1:

Deterministic

Approach

Calculation Mode 3:

Monte Carlo Method

Application:

High-Rise Building

Conclusion

Palisade Risk Conference in LondonSource:

Pro

duct

ivit

y [

%]

Construction time [d]

100 %

Adequate

Construction time

No go

Calculation of Construction Time: Calculation Mode 1

Hofstadler

231d

%1001

,

,,,,,

,

RCWT

CWABDARWABDAFWA

RCWRCW

CBURCW

BU

RCRRRCFRRC

WTW

QD

33ChristianHOFSTADLER2010 Construction Management

Analysis of Situation

Objective

Calculation Mode 1:

Deterministic

Approach

Calculation Mode 3:

Monte Carlo Method

Application:

High-Rise Building

Conclusion

Palisade Risk Conference in LondonSource:

The values from this table are used for the input variables to calculate total labour

consumption rate, daily production rate and duration (weighted triangular

distribution).

Calculation of Construction Time: Calculation Mode 3

Hofstadler

Average labor consumption rate - formwork works 0.60 wh/m 0.65 wh/m 0.90 wh/m

Average formwork ratio for the entire building 3.60 m/m 3.90 m/m 4.00 m/m

Average labor consumption rate - reinforcement works 7.00 wh/t 8.00 wh/t 10.00 wh/t

Average reinforcement ratio for the entire building 140.00 kg/m 150.00 kg/m 160.00 kg/m

Average labor consumption rate - concrete works 0.42 wh/m 0.45 wh/m 0.60 wh/m

Maximum number of workers 36.00 wh/hr 37.00 wh/hr 40.00 wh/hr

Proportion of the average number of workers 75.00 % 80.00 % 88.00 %

Daily working time 7.00 hr/d 8.50 hr/d 10.00 hr/d

Concrete Quanity 12,000 m 12,629 m 13,000 m

Buffer 7.50 % 10.00 % 13.00 %

MIN EXP MAX

34ChristianHOFSTADLER2010 Construction Management

Analysis of Situation

Objective

Calculation Mode 1:

Deterministic

Approach

Calculation Mode 3:

Monte Carlo Method

Application:

High-Rise Building

Conclusion

Palisade Risk Conference in LondonSource:

CT

1 =

20

2 d

5 %

CT

2 =

28

6 d

95 %

@RISK, Hofstadler

Calculation of Construction Time: Calculation Mode 3

Monte-Carlo Simulation Results: Duration (incl. Buffer)

35ChristianHOFSTADLER2010 Construction Management

Analysis of Situation

Objective

Calculation Mode 1:

Deterministic

Approach

Calculation Mode 3:

Monte Carlo Method

Application:

High-Rise Building

Conclusion

Palisade Risk Conference in LondonSource:

Change of Distribution Functions

?

Consequences

Isosceles

Triangular Distribution

Weighted

Triangular Distribution

Uniform Distribution Beta Distribution

Hofstadler

36ChristianHOFSTADLER2010 Construction Management

Analysis of Situation

Objective

Calculation Mode 1:

Deterministic

Approach

Calculation Mode 3:

Monte Carlo Method

Application:

High-Rise Building

Conclusion

Palisade Risk Conference in LondonSource:

Change of Distribution Functions

Hofstadler

0.000

0.002

0.004

0.006

0.008

0.010

0.012

0.014

0.016

0.018

150 200 250 300 350 400

Construction Time incl. Buffer [d]

Simulation 1 IsoscelesTriangular Distribution

Simulation 2 Weighted Triangular Distribution

Simulation 3 Uniform Distribution

Simulation 4 Beta Distribution

37ChristianHOFSTADLER2010 Construction Management

Analysis of Situation

Objective

Calculation Mode 1:

Deterministic

Approach

Calculation Mode 3:

Monte Carlo Method

Application:

High-Rise Building

Conclusion

Palisade Risk Conference in LondonSource:

Pro

duct

ivit

y [

%]

Construction time [d]

100 %

Adequate

Construction time

No go

Productivity and Construction Time

Hofstadler

38ChristianHOFSTADLER2010 Construction Management

Analysis of Situation

Objective

Calculation Mode 1:

Deterministic

Approach

Calculation Mode 3:

Monte Carlo Method

Application:

High-Rise Building

Conclusion

Palisade Risk Conference in LondonSource:

Equipment and materials costs - formwork 5.00 /m 6.00 /m 8.00 /m

Average formwork ratio for the entire building 3.60 m/m 3.90 m/m 4.00 m/m

Equipment and materials costs - reinforcement 400.00 /t 500.00 /t 600.00 /t

Average reinforcement ratio for the entire building 140.00 kg/m 150.00 kg/m 160.00 kg/m

Equipment and materials costs - concrete 80.00 /m 90.00 /m 95.00 /m

Average wage 27.00 /wh 30.00 /wh 31.00 /wh

Mark-up for overheads 10.00 % 14.00 % 17.00 %

Buffer 5.00 % 10.00 % 15.00 %

MIN EXP MAX

High-Rise Building Project - Key Details

Input values to calculate the construction time

Hofstadler

Labor productivityProduction

Rate

General construction

site conditions

Number of workers

Availability

Construction

method

Number of

equipment

General operating

conditions

Specific structural

conditions

Influences of the

construction method

Daily working time

Working time

scheme

Construction

method

Type of

construction projectLocation of the

construction project

Familiarization

Specific structure

conditions

General operating

conditions

General construction

site conditions

Practice

Influences of the

construction method

Work space

Staff qualification

Composition of the

working group

Disruptive

influences

External

Internal

Working time

regulations

39ChristianHOFSTADLER2010 Construction Management

Analysis of Situation

Objective

Calculation Mode 1:

Deterministic

Approach

Calculation Mode 3:

Monte Carlo Method

Application:

High-Rise Building

Conclusion

Palisade Risk Conference in LondonSource: Hofstadler

Calculation of the Cost of Production: Calculation Mode 1

Equipment and materials costs - formwork 5.00 /m 6.00 /m 8.00 /m

Average formwork ratio for the entire building 3.60 m/m 3.90 m/m 4.00 m/m

Equipment and materials costs - reinforcement 400.00 /t 500.00 /t 600.00 /t

Average reinforcement ratio for the entire building 140.00 kg/m 150.00 kg/m 160.00 kg/m

Equipment and materials costs - concrete 80.00 /m 90.00 /m 95.00 /m

Average wage 27.00 /wh 30.00 /wh 31.00 /wh

Mark-up for overheads 10.00 % 14.00 % 17.00 %

Buffer 5.00 % 10.00 % 15.00 %

MIN EXP MAX

%1001

%1001

,

,,,,,

RCWCOHDRCWEMARCWARCWACBURCW

BUMUcWATCRQCP

%1001

%1001

,

,,,,,

RCWCOHDRCWEMARCWARCWACBURCW

BUMUcWATCRQCP

40ChristianHOFSTADLER2010 Construction Management

Analysis of Situation

Objective

Calculation Mode 1:

Deterministic

Approach

Calculation Mode 3:

Monte Carlo Method

Application:

High-Rise Building

Conclusion

Palisade Risk Conference in LondonSource: Hofstadler

Calculation of the Cost of Production: Calculation Mode 1

Equipment and materials costs - formwork 5.00 /m 6.00 /m 8.00 /m

Average formwork ratio for the entire building 3.60 m/m 3.90 m/m 4.00 m/m

Equipment and materials costs - reinforcement 400.00 /t 500.00 /t 600.00 /t

Average reinforcement ratio for the entire building 140.00 kg/m 150.00 kg/m 160.00 kg/m

Equipment and materials costs - concrete 80.00 /m 90.00 /m 95.00 /m

Average wage 27.00 /wh 30.00 /wh 31.00 /wh

Mark-up for overheads 10.00 % 14.00 % 17.00 %

Buffer 5.00 % 10.00 % 15.00 %

MIN EXP MAX

CWABDARWABDAFWARCWA RCRRRCFRRCTCR ,,,,,,

Average labor consumption rate - formwork works 0.60 wh/m 0.65 wh/m 0.90 wh/m

Average formwork ratio for the entire building 3.60 m/m 3.90 m/m 4.00 m/m

Average labor consumption rate - reinforcement works 7.00 wh/t 8.00 wh/t 10.00 wh/t

Average reinforcement ratio for the entire building 140.00 kg/m 150.00 kg/m 160.00 kg/m

Average labor consumption rate - concrete works 0.42 wh/m 0.45 wh/m 0.60 wh/m

Maximum number of workers 36.00 wh/hr 37.00 wh/hr 40.00 wh/hr

Proportion of the average number of workers 75.00 % 80.00 % 88.00 %

Daily working time 7.00 hr/d 8.50 hr/d 10.00 hr/d

Concrete Quanity 12,000 m 12,629 m 13,000 m

Buffer 7.50 % 10.00 % 13.00 %

MIN EXP MAX

/19.4/45.0/15.0/00.8/90.3/65.0, mwhmwhmttwhmmmwhTCR RCWA

Equipment and materials costs - formwork 5.00 /m 6.00 /m 8.00 /m

Average formwork ratio for the entire building 3.60 m/m 3.90 m/m 4.00 m/m

Equipment and materials costs - reinforcement 400.00 /t 500.00 /t 600.00 /t

Average reinforcement ratio for the entire building 140.00 kg/m 150.00 kg/m 160.00 kg/m

Equipment and materials costs - concrete 80.00 /m 90.00 /m 95.00 /m

Average wage 27.00 /wh 30.00 /wh 31.00 /wh

Mark-up for overheads 10.00 % 14.00 % 17.00 %

Buffer 5.00 % 10.00 % 15.00 %

MIN EXP MAX

CWEMABDARWEMABDAFWEMARCWEMA cRRcFRcc ,,,,,,,,,,

/40.188/00.90/15.0/00.500/90.3/00.6,, mmmttmmmc RCWEMA

%1001

%1001

,

,,,,,

RCWCOHDRCWEMARCWARCWACBURCW

BUMUcWATCRQCP

41ChristianHOFSTADLER2010 Construction Management

Analysis of Situation

Objective

Calculation Mode 1:

Deterministic

Approach

Calculation Mode 3:

Monte Carlo Method

Application:

High-Rise Building

Conclusion

Palisade Risk Conference in LondonSource: Hofstadler

Calculation of the Cost of Production: Calculation Mode 1

Equipment and materials costs - formwork 5.00 /m 6.00 /m 8.00 /m

Average formwork ratio for the entire building 3.60 m/m 3.90 m/m 4.00 m/m

Equipment and materials costs - reinforcement 400.00 /t 500.00 /t 600.00 /t

Average reinforcement ratio for the entire building 140.00 kg/m 150.00 kg/m 160.00 kg/m

Equipment and materials costs - concrete 80.00 /m 90.00 /m 95.00 /m

Average wage 27.00 /wh 30.00 /wh 31.00 /wh

Mark-up for overheads 10.00 % 14.00 % 17.00 %

Buffer 5.00 % 10.00 % 15.00 %

MIN EXP MAX

%1001

%1001

,

,,,,,

RCWCOHDRCWEMARCWARCWACBURCW

BUMUcWATCRQCP

328,974,4%100

%101

%100

%141/40.188/30/19.4629,12, mwhmwhmCP BURCW

42ChristianHOFSTADLER2010 Construction Management

Analysis of Situation

Objective

Calculation Mode 1:

Deterministic

Approach

Calculation Mode 3:

Monte Carlo Method

Application:

High-Rise Building

Conclusion

Palisade Risk Conference in LondonSource:

The values from this table are used for the input variables to calculate cost of

production (weighted triangular distribution).

Calculation of the Cost of Production: Calculation Mode 3

Hofstadler

Equipment and materials costs - formwork 5.00 /m 6.00 /m 8.00 /m

Average formwork ratio for the entire building 3.60 m/m 3.90 m/m 4.00 m/m

Equipment and materials costs - reinforcement 400.00 /t 500.00 /t 600.00 /t

Average reinforcement ratio for the entire building 140.00 kg/m 150.00 kg/m 160.00 kg/m

Equipment and materials costs - concrete 80.00 /m 90.00 /m 95.00 /m

Average wage 27.00 /wh 30.00 /wh 31.00 /wh

Mark-up for overheads 10.00 % 14.00 % 17.00 %

Buffer 5.00 % 10.00 % 15.00 %

MIN EXP MAX

43ChristianHOFSTADLER2010 Construction Management

Analysis of Situation

Objective

Calculation Mode 1:

Deterministic

Approach

Calculation Mode 3:

Monte Carlo Method

Application:

High-Rise Building

Conclusion

Palisade Risk Conference in LondonSource:

Calculation of the Cost of Production: Calculation Mode 3

Monte-Carlo Simulation Results: Costs (incl. Buffer)

@RISK, Hofstadler

CP

1 =

4,6

4

5 %

CP

2 =

5,4

0

95 %

44ChristianHOFSTADLER2010 Construction Management

Analysis of Situation

Objective

Calculation Mode 1:

Deterministic

Approach

Calculation Mode 3:

Monte Carlo Method

Application:

High-Rise Building

Conclusion

Palisade Risk Conference in LondonSource:

Change of Distribution Functions

?

Consequences

Isosceles

Triangular Distribution

Weighted

Triangular Distribution

Uniform Distribution Beta Distribution

Hofstadler

45ChristianHOFSTADLER2010 Construction Management

Analysis of Situation

Objective

Calculation Mode 1:

Deterministic

Approach

Calculation Mode 3:

Monte Carlo Method

Application:

High-Rise Building

Conclusion

Palisade Risk Conference in LondonSource:

Change of Distribution Functions

Hofstadler

0.0000000

0.0000002

0.0000004

0.0000006

0.0000008

0.0000010

0.0000012

0.0000014

0.0000016

0.0000018

0.0000020

4,000,000 4,500,000 5,000,000 5,500,000 6,000,000 6,500,000

Cost of Production incl. Buffer []

Simulation 1 IsoscelesTriangular Distribution

Simulation 2 Weighted Triangular Distribution

Simulation 3 Uniform Distribution

Simulation 4 Beta Distribution

46ChristianHOFSTADLER2010 Construction Management

Analysis of Situation

Objective

Calculation Mode 1:

Deterministic

Approach

Calculation Mode 3:

Monte Carlo Method

Application:

High-Rise Building

Conclusion

Palisade Risk Conference in LondonSource:

Construction Time and Construction Costs

The specification of a reasonable construction time makes a substantial

contribution towards the economical use of elementary and discretionary

production factors, or at least creates the preconditions to do so. Workers,

equipment and materials can be used cost-efficiently.

A realistic construction time can be calculated once construction management

boundary conditions have been considered.

Hofstadler

Pro

duct

ivit

y [

%]

Construction time [d]

100 %

Adequate

Construction time

No go

47ChristianHOFSTADLER2010 Construction Management

Analysis of Situation

Objective

Calculation Mode 1:

Deterministic

Approach

Calculation Mode 3:

Monte Carlo Method

Application:

High-Rise Building

Conclusion

Palisade Risk Conference in LondonSource:

Many Thanks!

Hofstadler