Process time information system (PTIS) for productivity improvement

Process time information system (PTIS) for productivity

improvement

Citation for published version (APA):

Erkelens, P. A., & Schaefer, W. F. (1986). Process time information system (PTIS) for productivity improvement. In IABSE Workshop Zurich 1986: organization of the design process - proceedings (pp. 67-78)

https://doi.org/10.5169/seals-41112

DOI:

10.5169/seals-41112 Document status and date: Published: 01/12/1986

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productivity improvement

Autor(en): Erkelens, Peter A. / Schaefer, Wim F.

Objekttyp: Article

Zeitschrift: IABSE reports = Rapports AIPC = IVBH Berichte

Band (Jahr): 53 (1986)

Persistenter Link: http://doi.org/10.5169/seals-41112 PDF erstellt am: 26.06.2019

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67

A

Process

Time

Information

System

(PTIS)

for

_Productivity

_Improvement

Systeme

informatise

de

_{temps d'execution pour}

_{l'amelioration}

de

la

_productivite

Ein

_{Vorgangszeit-Informationssystem}

_zur

_{Produktivitätssteigerung}

Peter

A.

ERKELENS

Senior Lecturer,

University of Technology

Eindhoven,

The

Netherlands

Wim

F.

_SCHAEFER

Research

Fellow,

Computer

Applic.

University

of

_Technology

Eindhoven, The

Netherlands

1

Born

in

1946. M.

Sc.

Civil

_Engineering,

1969

University

of

Technology

Delft;

4

years

Shell

International;

3

_years

Low

cost

housing

expert

Kenya;

Lecturer since

1974.

r

Born

in

_1952.

_M.

_Sc.

Building

Engineering,

1978

_University

of

Technology

Eindhoven;

4

_years

Architectural

Company;

Research on

applied

Computing

sciences

since

1982.

SUMMARY

The

fast

_development

of electronic

data

_processing

makes

it

_{possible to}

_develop

a

_process

time

information

_system

for

the

construction

_industry.

This

_system

under

_development,

calculates

process

times

in

the project

preparation

phase and

the construction

phase

and

_{will contribute}

_to

productivity

improvement.

This

_{paper gives}

an

_expose

of

research

_{being undertaken.}

RESUME

Les

_{developpements}

_rapides

dans

le

_traitement

_electronique

_{des donnes}

_rend

_possible

la

realisation

d'un

_Systeme

informatise

de

_{temps d'execution}

dans

l'industrie

de

la

_{construction.}

_Ce

Systeme, en

cours

de

developpement,

calcule

les

_{temps d'execution}

dans

la

_{phase de}

_preparation

du

_{projet et}

dans

la

_phase

_de

_{construction,}

_et

_contribue

_ainsi

ä

l'amelioration de

_la

productivite. L'article presente

les

recherches

_{entreprises actuellement.}

ZUSAMMENFASSUNG

Die

rasche

_Entwicklung

der

_{elektronischen Datenverarbeitung}

hat

die

_Möglichkeit

für

die

Anwendung

von

dynamischen

Planungssystemen

im

Bauwesen

_geschaffen.

Das

hier

_beschriebene

System

berechnet Vorgangszeiten

in

der

_{Arbeitsvorbereitung}

und

während

der

_Ausführung

_von

Bauprozessen.

Damit

kann

eine

_{erhebliche Produktivitätssteigerung}

auf

der Baustelle erzielt

1. INTRODUCTION

The Netherlands Government has embarked on an extensive programme

for

the promotion and _development of technological innovations in

all

important industries. Through an innovative research programme (so

called

IOP) the government subsidizes since 1979 those- research

projeets

in

universities

and _other

institutes

which are of importance

for

industrial

development.

The IOP research for the construction industry (lOP-Bouw) started

in

1983. The _basic idea

is that

a _good and

_generally

aeeepted

information technical

infrastructure for

the construction industry

is

an _important condition

for

Optimum innovative development.

Here-with the

_fast

developments of automation

tools

can provide excellent

opportunities.

An information technical

infrastructure is

meant _to be a _system of

Conventions which enables the

various

parties in

the

_building

process to communicate

with

each

_other,

with

_{the support} of

auto-mated information Systems.

In the

field

of electronic

data processing (EDP) the three main

fields

for

research and _{development are:}

* _coordination and communication;

* _information

_{transfer, Instruction}

and _education;

* _{socio-economic aspects.}

One

of

the research

projeets

is

the development of a _process time

information system (PTIS)

for

the construction firm.

2. BACKGROUND

Due

to

changing market

conditions

and

other

ways of execution

of

building

projeets, contractors in

particular,

have a _growing demand

for

specific

information. An _{important part}

is specific

information

on time data of

all

activities -in

general and

in

detail-during the

realization

process. Some of _{the reasons are:}

-

There

is

a move from new construction towards town

rehabilita¬

tion,

renovation and maintenance. This causes a

different

task

content

for

the craftsman. The number

_of

_Operations to be

performed by a _person or a _gang

is generally

growing; A task

used _to be performed by one person/gang; we now see more activities

are brought under one task. We _speak of the creation of so

called

"intelligent

gangs" and the use

of

"muiti-functional"

craftsmen.

The

_building

_process can develop more smoothly when technical

and _{organizational}

relations

can be disconnected. For example

the support &

infill

concept shows a

"layering"

during the

design phase but also during the

realization

phase. The _support

is

manufactured _separately from the

infill.

This requires also

a

different

work preparation of the

realization

phase.

The

introduction

of EDP _provides

possibilities

for improving and

speeding up the information processing.

It

is

possible to störe

information, to

retrieve

information, to compare

alternatives

and

_to

arrive

at

better

decisions

(i.e.

decision

support

4

PA ERKELENS, W F SCHAEFER 69

other

_'levels'

in

the Organization and

for

_{other partners} in the

building

process.

In the _{construction industry} the

_{productivity is}

_lagging behind

compared with other industries. There

is

a wish to measure and

to

influence

the

_productivity

development. At

_project

level

this

can be obtained by a better

registration

of

all

inputs and

Outputs. This

is

part of a research

project

undertaken by

this

university

(see also

Cl]).

3. PTIS IN GENERAL

The aim

_of

the research

_project

PTIS

is

the development

of

a process

time information system, which can be used _during the

_building

project preparation and

realization.

This provides the

_possibility

that decisions

related

to time can be taken in a

better

_way.

A _process time

is

defined as the progress time

of

a

building

process

at a low or an _aggregated

level.

It

is

a function of capacity,

allowances and

_building

_process volume (e.g. man-hour).

The

_University

works on

this

project

_together

with

the Research

Institute

for

Labour Economy

in

the

Building

Trade (SAOB). This

Institute

has numerous time-motion data

_available

from

_building

site

activities.

However these data are not

_easily

accessible.

Due to

technical

_developments

in

the

field

of

EDP

it

is

now

possible

to

structure

_and

to

_combine these data

for

interactive

use

even at the

_building

site.

The PTIS system

will

function

as a decision support _system. Van

Hee [2] _gives the

following

characteristics of such a _system:

1. Upon

actions

as chosen by the user, the system

calculates

the consequences

in

the form of

ratios

which provides the user a

better insight

in the produetion process.

2. Upon a

criterion

as chosen by the user, the system optimizes actions and

_calculates

_related

ratios.

3. Once

certain

actions

_are chosen, the system determines the

sensitivity

for variations in

parameter values.

It

represents

in

the

ratios

the effects of these

variations.

The research approach

is

the

_following:

firstly

the

available

information

has

_to

be

identified,

structured

and _completed. For

this

purpose

accessible

data bases have

to

be _created and

_also

proper working

definitions

are required. Secondly procedures have

to be _developed

for

_quick,

effective

and

interactive

use of structured

process time data. The data bases and the information processing

procedures are the main components

of

PTIS (see _Fig. 1).

This system can be

_integrated

in

a more complex

building

process information system, to be developed at a

later

_stage, which

is

also

COMPANYPRDJECT-DATA

DATA

DATA

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H- C^

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J% P.A. ERKELENS,W.F. SCHAEFER 71

4. INFORMATION ORDERING

4.1

_Activity

Groups and Mile Stones

The

materialization

sub-phase forms together with the commercial

phase

(project

tendering

etc.) the

realization

phase (Fig. 2). This phase has three _groups of

activities:

Work _preparation

activities:

These _are considered to be information

transforming processes. The

results

_are decisions and/or

descriptions

for specific

execution

_activities.

Information from contract documents, work Organization and

site

_{data are} combined

and _transformed

into

_plans such as a material planning, personnel

planning etc.The execution

activities

are simulated as aecurate as possible.

IL^^HtL0.!!

activities:

These are considered

to

be

material

transforming processes. The

_quality

_{of the execution}

activity

is

mainly determined by the _preparation- and

control

activities.

-

Oont£ol1

activities:

The execution

activities

are checked by

comparing The~TnTö"rmation from the execution with

relevant

information from the work _preparation and _{then generates}

control

information.

It

is

therefore an information comparing process

and

_control

_{information generating proce««;.}

CDNTRACT DDCUMENT .PHASE

REALIZATIDN

PHASE

USE PHASE COMMERCIAL SUB-PHASE CONTRACT TENDERING AVARD MATERIALIZATIQN SUB-PHASE PREPARATION EXECUTION CONTROL

Currently there

is

no suitable method

available

for

the Classification

of information on

activities

in

the

materialization

phase.

The _planning of the sequence of

building

activities

is

in general

the

guiding

principle.

Though experiences and

_{possibilities}

_for

information processing may

differ

by contracting firm.

The _{information in}

this

_phase

_is

_ordered

_in

a _process oriented _way.

This

is

contradictory

to the

_{object oriented ordering}

during the

design phase. The basis

for

the _ordering

_principle

is

the

hierar-chic

structure:

processes are top down sub

divided

in smaller

processes.

The

relation

between the _processes at

all

levels

is

indicated by a

code. Also the

mile

stone _concept, as being used

for

network

planning,

shows such a _top down

structure

_(Fig. 3

[3]).

In

this

way

building

processes can be structured top down.

MILESTONE PLAN level 2. MILESTONE PLAN/ level 1. / \ \ v _\ * \ L*4

l

NETWORK PLAN

Mkm.

P A ERKELENS,W F SCHAEFER 73

It

is

also necessary

to

structure the

building

process in a

chrono-logical

order. The proposed phasing of the so

called

main

_building

processes

is:

-

start;

-

substrueture;

-

superstructure: frame;

-

facade;

-

roof;

-

infill;

-

finishing;

-

end.

Each

_building

main _process can be defined by

its

start-point

and

end-point. This

is

similar

to the way an

information

_process

is

defined by

its

inputs

and _Outputs. The

start

and the end of each

building

main-process can be

identified

as a

mile

stone. This

is

also a measure

_point

see Fig. 4).

The MATERIALIZATIDN PHASE

subdsvlded In

8 CDNSTRUCTIDN-ACTIVITY-GRDUPS

1. _START

End _{neasure points} SITE PREPARED

2. SUBSTRUCTURE

End _{neasure point«} SUPPORTING STRUCTURE

REALIZED UPTO LEVEL

3. FRAME

End _{neasure point«} SUPPORTING STRUCTURE

REALIZED TILL ROOF

4. FACADE

End _{neasure point«} FACADE IS

VATER & WIND TIGHT

5. RDDF

Zr\d _neasure point« ROOF IS

VATER &. _{VIND TIGHT}

6. _INFILL

End _{neasure point«} INTERNAL SPACES

ARE SEPARATED

7. FINISHINGS

End _{neasure point«} BUILDING COMPLETED

FOR DELIVERY

8. END

End _{neasure point«} SITE COMPLETED

FOR DELIVERY

Fig. 4 Building _phases and mile stones 4.2 The _Building Sub-Process

For a _top down _{structure of} the _{building process,} we can

distinguish

the _following classes _{of building} processes:

building main _processes of the

materialization

phase;

building sub-processes as a _part of one main _process;

Operations as a

part

of more sub _processes;

-

actions as a _{part of more Operations;}

Fig. 5 shows the complete

picture.

_{The processes are}

discon-nected. This allows

for

another _ordering of the

building

process,

reconstruction etc.

1. START 2.

SUB-STRUCTURE FRAME. FACADE RDDF 6. INFILL, 7.INGSFINISH 8. END

«nr

BUILDING

SUB-PRQCESSES

OPERATIONS ACTIDNS

Fig. 5^ Hierarchy of building processes

The

level

of _{sub-processes,}

_is

_{in practice the}

_level

_{for generating}

work-tasks. This

will

also be the

_level

on which work preparation

and _{execution are} focused

_within

_this

_research

_project.

_This

_level

will

therefore be considered _in more

detail.

The

_following

information

is

required:

Labour economical information Coming from information on Operations

(Standard data);

Building technical

information

coming from the

object

to be

realized

(project dependent) and from the

available

techniques

(contractor

dependent);

Building

phase

information

dependent

of

the

_object

to be

realized (project

dependent) and the

available

techniques

(contractor

dependent).

The time data

of

the actions are

inclusive

productive,

indirect

productive

and _{improductive time:} a

nett

time

with

allowances.

Theoretical

_ly

time data of Operations can be

built

_up from time

data of actions. However most of these Operations are complex and

the usual tuning losses at

_{this level}

are not included then. Most

P.A. ERKELENS,W.F. SCHAEFER 75

4.3 Grouping Technology

Each craftsman has a

(limited)

field

of

experience and

expertise

(carpentry, masonry

etc.).

Each _piece

of

_equipment has

its

own

working

characteristics.

When we make a planning

for

_example

for

a

sub-process) the Computer can optimize the composition of a _{gang by}

a

clustering

strategy and takes

into

account the various

fields

of

expertise of the workers and the

characteristics

of the equipment. This can be worked out

in

two ways

(i)

bottom up and

(ii)

top down:

(i)

Often sub-processes can be executed

in

different

ways

with

different

combinations

of actions/operations.

By

analyzing

at a

low

level

the _{requirements (expertise,}

_{characteristics),}

the next

higher

level

can generate a number _of

alternatives.

(ii)

Actions/operations

have a

certain

degree

of

relationship.

Partly

they have a number

of

the same movements and _they may

require the same

skills,

tools

and equipment. By breaking down

sub-processes the Computer may

try

to combine those actions/operations

which have a

certain relationship.

These combined actions/operations

require common

skills,

tools

and _equipment. This can be the

basis

for

the

planning of

gangs and

individuals.

The user can

select one of the presented

possibilities.

5. _„ PTIS SYSTEM DEVELOPMENT

5 .1 Introduction

A number _of methods are

available

for the development of a Computer based information processing system. The differences between these

methods _are

_essentially

_marginal. The _applied method

is

developed

by DeMarco- Yourdon

[4]

and

is

used by many

multi-

nationals. The

characteristics

of the method

_is

the top-down

analysis

whereby a

distinction

has to be made between data and _process

[5].

Processes

are

indicated

with

bubbles;

input-

and _{Output data}

flows

with

arrows

_relating

the bubbles (Fig. 7).

For the development

of

the system

it

is required

to

interview

contractors

for

their

ideas on the Output

of

PTIS: How do _they want

to use the system. The _Output

_descriptions

will

be the basis

for

the input Organization.

5_{.2 System Component: Time Data}

The _ordering

of

data belonging to process time and _{process time}

variables,

is in

accordance with the ordering of

building

processes

as shown

in

Fig. 5. The _ordering of the time data

within

a

building

main _process

is similar

_{to these process} classes (Fig. 6):

time data of a main _process

built

_up of time data of one or more

sub _processes;

time data

of

a sub _process

consisting of

time data

of

one or

more Operations;

time data of an Operation consisting of time data of one or more

actions;

TUNING LDSSES (TL) (TL)

Sr*

<TL) BUILDING MAIN-PROCESS BUILDING SUB-PRDCESSES TIME DATA DF OPERATIONS TIME DATA OF ACTIONS Fig. 6^ The ordering of time

within

a

building

main-process

A

first

_{rough concept}

_of

_{the system}

_requires

_the

_following

databases

:

a data base of labour and equipment time. Based on information

of action times and _{Operation times;}

a data base with

specific

information of the Company (time data

etc

);

-

a data base with information on _{recent projeets.}

A _{program can}

_calculate

all

_{possible process time}

_variations

be-longing

to

different

methods _of execution. 5.3 System Component: Processes

The _lowest

level

_{of data (actions and also Operations)}

_is

_in

principle _{manually loaded}

in

_{the system and permanently stored}

_in

_a

data base. The data

for

a

building

_{process time at any}

level

is

generated through a _procedure of information _{transforming activities.} Hereby the lowest

levels

of

data serve as the

_input

for

these

_activities.

The _{classes of information transforming}

_activities

_are

_similar

_to

the ordering of time data. The

_following

_{process time data can} be

calculated

for:

Operations based on time data of _actions added with allowances;

sub _processes based on time data of Operations added _{with tuning}

losses;

main _processes based on time data of sub _processes and _tuning

losses;

materialization

phase based on time data

of

main _processes, overlaps and _{tuning losses.}

Fig. 7 _shows

in

_{a schematic way these}

_four

_levels

_of

_{classes as}

P.A. ERKELENS, W.F. SCHAEFER 77

c

c

]

TIME DATA GF THE MATERIALIZATION PHASE 4. CALCULATION DF

THE TIME DATA qF

THE MATERIALIZATION PHASE TIME DATA DF BUILDING MAIN-PRDCESSES 3. CALCULATIDN DF

THE TIME DATA DF

A BUILDING MAIN-PRDCESS TIME DATA DF BUILDING SUB-PRDCESSES 2. CALCULATIDN DF A BUILDING SUB-PRDCESS TIME DATA DF OPERATIONS 1. CALCULATIDN DF TIME DATA DF OPERATIONS TIME DATA OF ACTIONS

Fig. 7 Levels of classes of information

PRODUCTIVITY AND PTIS

Productivity

in

the

_building

_industry

is

an _important area

of

research

_Cl].

The

definition

for

_{productivity is}

the

ratio

of

Output and

_input.

Sofar no

revolutionary

ideas have come up.

Produetion

factors

like

men, money, machines and

material

can be expressed

in

terms of money, time or

quantitities

or related dimensions.

The measurement of

productivity

and

_{Interpretation}

_of

ratios can be used as a management

tool.

The determination of a _{process time can} also be used as a

tool

for

the

determination

of

the

_{productivity.}

We _can

think of

the

(single-)factor

produetivities

like

labour-, equipment-

material-,eapital-,

and _management

_{productivity.}

The

total

_productivity

can

be the

total

of the above. When we have calculated various process time

_{possibilities}

for

a

building

_{process the}

productivity

of the

applied produetion factors can be a _yard

stick

for

the

selection

of a _process time

variant.

7. HOW TO WORK WITH PTIS

At the

_highest

_level

one

is interested in

a _process time

of

a

building

main _process or a _sub-process time of the construction of

a

super-structure,

a

wall.

For

tendering

_purposes one may need a

rough time schedule

for

the

calculation

of the time related cost.

At the execution

level

one may be

interested

in

time data

for

working plan schemes and

for control

_of the

_project.

The _work-planner makes an

overall

time _plan with PTIS. The

organi-zer/planner

can make

detailed

_plans and work schedules

_for

the

site:

a _rough planning 4 weeks ahead and a

detailed

plan 2 _weeks

ahead. When the contractor is introduced

in

an

early

_stage of the

project,

the _{required planning}

is

at a mile stone

level:

for

main-or sub-process.

The

selection

_{of the type of planning}

is

_by means of a menu structured

programme. The

results

can also be

visualized

on the screen

in

the form _of schedules for labour, equipment, material, etc. Due

to the

interactive

programme»

it

is

possible to modify input at

all

levels

and _to ask

for

a

calculation

of the _{consequences.}

8. RESULTS AND CONCLUSIONS

The

_results

_of

this

_{research are at}

this

_stage:

a series of

definitions

for the labour economic aspects. Those

definitions

were not complete or very vague.

a _system design

for

a _process time

information

_system. The

development

of

a

steering

_programme

to

activate

existing

pro-gramme-modules as

for

example a network _programme.

a

calculation

method

for

_process times

for

_all

the

_levels

in the

building

process and

for

all

_{types of construction.}

Although

this

project has shown some

fields

which need

further

research,

it

will

be

feasible

in

_{the near}

_future

_{to develop} a

fully

working PTIS. This can be extended with other programmes

in

the

field

of

cost and

_quality.

_{Also the designers can use}

this

system

for

their

preliminary considerations. They can get

an

indication

of the time _consequences

of

their

_design decisions

9. REFERENCES

1. SIKKEL _L.P. and ERKELENS _P.A.,

Productivity

and _Productivity

Factors in the Building Industry. IABSE Journal J-25/84,

Zürich, 1984.

2. Van HEE _K.M.,

Tijd

_voor

informatie

_{management. Inaugural}

Lecture,

University

of Technology, Eindhoven, 1985.

3. GROH H. and GUTSCH _{R.W., Netzplantechnik. VDI Verlag,}

Düsseldorf, 1982.

4. DEMARCO T., Structured Analysis and _{System Specification.}

Yourdon Press, 1979.

5. DINJENS P.J.M. and SCHAEFER W.F., Design Methodology

for

CAAD

Packages Vol

III-V.

Research _Project Group Design Methodology,