EXPERT SYSTEM FOR COMPETITIVE BIDDING OF AN ELECTRICAL INSTALLATION PROJECT

Presented By : T. M. WeerakkodyReg. ID : 108894F

Supervised By : Dr. KTMU Hemapala, Dr. AGBP Jayasekara

4TH PROGRESSING REVIEW

Introduction (Problem and Motivation) Competitive bidding used for Electrical contractor selection To win a bid, requires reliable & good decision making process Mostly heuristic knowledge involves in the process Human expertise is very scarce Even find, they have limited working memory, get tired & slow in recalling information The solution is to find more accurate knowledge base system

What are the benefits of knowledge base system

Help distribute human expertise Increase probability, frequency & consistency of making good decisions Free up mind & time of human expert Facilitate real time, low cost expert level decision by non expert

Introduction • Bid preparation process

Project details Bid

Experience and norms

Preparation of bid

Problems with competiveness of

the bid

Due to- Lack of experience- Incorrect material take off- Unclear scope of work- Fluctuation in material costs- Uncertainty in taxes & duties

Solution: Hire expertise teamUse of an expert system

Expert Systems approach for electrical estimation

Expert System Requirements,a) Implementation of Static Knowledge (facts)b) Flow chart interpretationc) Implementation of Dynamic Knowledge (rules)d) Implementation of Inference engine e) User interface

An expert system is a computer program that simulates the thought process of a human expert to solve complex decision problems in a specific domain

Competitive Bid Value

Material Cost Calculations

Labour Cost Calculations

1) Bidding docs

2) BOQ

3) Construction Dwgs

4) Electrical specs

5) Pre-bid meeting & visit

6) Material take off

7) Material cost input

8) Labour cost input

9) OHP input

Proposed system for the competitive bid estimationof an electrical installation project

Overhead & Profit Calculations

Expert System

Infe

ren

ce

En

gin

e

What are behind experts’ mind

1. Setup procedure for estimation2. Identify relevant material & labour depending on the scope of work3. Knowledge of Market prices of Materials & Labour and its fluctuations4. Value added areas that make the proposal more competitive5. Preparing of the Final Bid Value6. Judgment on competitiveness of the

final bid value

Satisfy Prequalification

Estimation Procedure

Search & verify followings

Type of contract

Pricing for BOQ Items

List out electrical items

Identify Material Involvement per

each item

Identify Labour involvement per

each item

Selected material for pricing = technical

specification

Material take off from the drawings

Overhead and profit input

Select pricing method

Identify scope of work per each

item

Labour input

Get Market price for selected &

quantified materials

Verify overhead requirement for

the project

Basic Labour cost per item

Add overhead & profit to basic

valueFinal BOQ Value

Collect Tender Documents

Basic Material & Labour for Total

BOQ

Costing Material input

Basic Material cost per item

Estimation Procedure Most Critical Tasks that Expertise Involvement is required

Static Knowledge Base for Bid estimation ( Electrical)

1. Bidding documents related information2. BOQ, specifications, drawings information3. Indirect cost dependant factors 4. Material pricing and quantifying5. Labour rates input6. Overhead and profit calculation

1. Bidding Documents related information– Main follow ups

a) General Informationb) Availability of relevant documentsc) Missing information, insufficient details, unclear informationd) Prequalification and supportive documents submissione) Selection of the type of the contractf) findings on building status or installation status

2. BOQ, specifications, drawings – Main follow ups

a) Categorizing of main electrical installation types b) Selection of no of types relevant to each categoryc) Insertion of material details in each typed) identify measuring unit for each materiale) Quantifying per unit measurements

Main Categories

3. Indirect cost dependant factors

a) Contractor efficiency on completion of projectsb) Contractor strength on maintaining cash flow of the projectc) Labour management strategies depending on the projectd) Prediction on future cost fluctuations in any categorye) Relationship build up with suppliers and other contractorsf) any indirect expenditure which leads for extra overhead costing

4. Material pricing and quantifying / 5. Labour rate input

a) Rough material take off for getting supplier quotation for the projectb) Summering total quantities for the projectc) Call quotation from suppliers with which the contract specification is complied d) Include material prices on relevant BOQ itemse) Insert exact quantities each type of item which is categorizedf) Get labour rates for each job from labour contractor or by using historical datag) Add labour rates for each type in BOQ items

6. Overhead and Profit Calculation

a) Select site staff, equipments, tools etc, overhead cost for the total project periodb) Distribute total overhead to each BOQ items so that basic material & labour cost plus overhead equals to final bid value

Flow chat approach for the Expert SystemBidding Docs 1

Bidding docs details are

clear

Submit & finalize unclear items from relevant

parties

Submission of bid security with correct

validity period

Remind the pending docs to

project mgt team & get it done

Bid docs are duly signed by

authorized persons

Remind the pending docs to

project mgt team & get it done

Attachment of neccessary

supportive docs

Remind the pending docs to

project mgt team & get it done

Insert in the docs submission

file

No

Yes

No

No

No`

No

Yes

Yes

YesYes

Yes

Yes

Yes

Continue from ''clarify all

disputes in pre-bid meeting''

Continue from ''Make assumption for items with lack

of details & submit in the offer

Bidding Docs

1

Expert System Flow chart approach

BOQ Docs 2

Details of the BOQ is clear

Desctiption of the BOQ is

having deficiencies

Summerize the dispute items

Soft copy of the BOQ is recieved

Type BOQ in excel format

BOQ details are matched with

construction dwgs

Summerize disput items

BOQ details are matched with specifications

Summerize disput items

Continue from ''clarify all

disputes in pre-bid meeting''

Continue from ''select BOQ item to be estimated

No

No

No

No

Yes

Yes

Yes

Yes

BOQ Docs

2

Flow chat approach for the Expert System

Findings from Site

Visit

Site Visit is carried out

Any deviation from the

original scope

Continue from ''select BOQ item to be

estima

Continue from ''clarify all disputes in

pre-bid meeting''

Details of the site condition are identified

Building status

Newly proposed Building

Refurbished old building

removable items are available

Reusable items are available

Measurements to be added in labour cost

Measurements to be added in Material cost

Continue from ''identify material

brand, type & standard from the

specification

Risk of uncertainty

factors should be taken into account

Allowance for extra cost of travelling is necessary

Allowance for extra cost of healthcare is

necessary

Allowance for extra cost of

accommodation is necessary

Working condition of

the site

a

g

b

Measurement to be added in the overhead

calculation

Working time duration of the

day is identified

Any existing site operations that effects to the working time

Any hindrance for working over time

Measurement to be added in

the Labour cost

calculation

Yes

Yes

Yes

Yes

Yes

No

No

No

NoSite Info

3

Flow chat approach for the Expert SystemContinue from

''select BOQ item to be estimated

Material Cost Calculation

Project is based on Duty

free BOI approved

Supply of material by

client

Go to Labour cost

calculation

Rates are only for

labour work

Supply of materials by

client

Clearance, bank charges & others paid

by client

Measurement to be added in the

overhead calculation

Rates are included for

complete job

Add duty component for

final cost calculation

Identify material brand, type & standard from

the specification

Continue from ''Newly

proposed building''

Inquiry from the material supplier for quotations

Check quotations are

compatible with specs

Evaluate supplier

quotations for best prices

Add prices to discount schedule for material cost

calculations

Continue from ''Get supplier

commitment & futher discounts for bulk supply''

Material take off relavent to the BOQ

item

Soft copy of the drawing is

available

Scale of the hardcopy is

correct

Prepare the drawing for

take off

Scale factor to be taken & multiply

with it for measurements

Select & group locations of

identical point arrangements &

distribution

Continue from ''Sort list BOQ

items same rate according to

dwgs''

MaterialCost

4

Continue from ''Sort list BOQ

items same rate according to

dwgs''

Circuit wirings are shown in

shown

Sketch most possible circuit arrangement in

the dwgs

Measure average

conduit length per point

Measure average length of neutral

& phase wires per point

Measure average length of earth wire

per point

Measure percentage

switch involvement

per point

Continue from ''Get supplier

commitment & futher discounts for bulk supply''

Measurements to be added in Material cost

calculation

Prepare Material cost

calculation

Get total materials quantity for requesting

discount from the supplier

Get basic material cost

Calculate wastage & acc per point as %

qty of material

Add tools & Machinery cost basd on basic material cost

Final Material cost in the rate analysis related

to selected BOQ item

Flow chat Diagram of the Expert System – Section 5

MaterialCost

4

Continue from ''select BOQ item to be estimated

Labour cost calculation for point wiring

Labour cost calculation for point wiring

Calculate the labour cost for the complete

project

Main job is covered by

direct labour

Get sub contractor rates

for the job

Get labour cost by calculating

labour requirement

Compare the measured cost with hystorical data analysis

Adjust labour cost depending on the

material usage accoding tho the

location

Get the basic material cost

Get the basic material cost

Basic labour cost & predicted labour

schedule cost are matched

Multiply basic labour cost by a factor to

compensate OT work during the project

Final labour cost in the rate analysis

related to the BOQ item

Adjust the basic labour cost so that predicted labour schedule cost are

matched

Flow chat Diagram of the Expert System – Section 6

LabourCost

5

Implementation of Dynamic Knowledge (know how, rules) by using a general resolution procedure

Bidding Docs

1

Implementation of Dynamic Knowledge (know how, rules) by using a general resolution procedure

BOQ Docs

2

Implementation of Dynamic Knowledge (know how, rules) by using a general resolution procedure

Site Visit

3

Implementation of Dynamic Knowledge (know how, rules) by using a general resolution procedure

Others4,5,6

Software Development1. Interface Development (Data acquisition and Output result)2. Implementation of expert system procedure

SummerySoftware Development (System Information)1. Developing software – Visual Studio 20102. Language – C #

Achieved so far,1. Problem Identification2. Corrective action with proper solution3. Data acquisition incorporated with the expert system concept4. Implementation of the system 5. Software Development6. Fine tuning the system based on expertise comments

Conclusion,This research will inspire the construction industry to be more active and vigilant about having an ultimate solution for electrical bid estimation.

Future direction1. Development of the software in commercial Level 2. Expand the system which would cover M&E installation

Thank You !