planning practise

8/4/2019 Planning Practise

1/40

1 Units for Planning Planning workhours per week: 56 Planning workdays per week: 7 Planning weeks per month: 4.3

2 Structural Works Cycle Time Cycle time for in-situ RC high-rise building using system FW: 9-12d Cycle time for in-situ RC high-rise building using conventional FW: 13-16d Cycle time for the initial story or roof part: 17-20d Cycle time for steel structure with Bondek system: 5-7d3 Architectural Works Cycle Time3.1 General sequenceSkim coat (before brickwall to have no-block move around of the scaffold) > Brickwall and window / doorframe > M and E piping > Internal plastering > Waterproofing >Screeding > Aluminium Works (refer to theframework. The external aluminium works can start when the structure goes up to certain level so that

the frame work can work downwards) > Wall tile / marble > Suspended ceiling > Floor tile / marble >Window glazing > Kitchen cabinet > Wardrobes > Floor parquet > Door panel / ironmongery > Internalpainting > Sanitary ware > External plastering > External painting (external plastering and painting areindependent from internal finishing works).

3.2 Cycle TimeThe architectural works is carried out trade by trade. The cycle time for each trade shall not be fasterthan the structural work cycle time.

4 Sectional Construction Period 1 Basement including piling work: 6-10m Architectural and M&E works after completion of structural works:

- For Condominium: 6m

- For Factory: 4m

5 Construction Joint and Zone / Block Follow the design sector, e.g., block, pour strip, etc. 1/3 of a beam Consider pre-stressed concrete length for work. The pour strip is a natural division. Not more than 800-m2 Consider access when sequencing construction zones (not to block the access)6 General Architectural Works Sequence

6.1 Internal Finishes When N-level is under structural construction, the N-1 level is maintained propping and strutting. The

N-2 level starts brickwork and followed by M&E piping.

Wet first then Dry. That is to say, for a room or a confined space, start wet trades (skim coat,plastering, floor screeding, tiling, marbling, etc.), then dry trades (partition, carpentry work, steelwork, etc.).

Top first then down. For several concurrently running wet trades or dry trades, work startsfrom the ceiling, to the wall, to the kicker and floor. For example, normally, do suspended ceilingfirst, then do floor marble and tiles. This is because the finishing sealant to the ceiling panel issomehow a wet trade, and may drop down to the floor.


2/40

6.2 External Finishes Generally, there is no constraint between internal and external finishing works. Two types of external finishes: wet and dry. Wet refers to the traditional painting, and dry refer

to the envelope type of curtain structure attached to the structure, such as cladding stone, curtainwall, etc.

Vertically, for a high-rise building, it may divide the whole external wall into several zones andseparate them with temporary protection platform. Sequence is always from the top to down.

7 General M&E Works Sequence From the view of the system, the M&E works can be categorized as plumbing and sanitary works,

electrical works, mechanical ventilation and air-conditioning and fire protection system.

From the view of the actual work, the M&E works can be sequenced as: sleeve penetration andembedded components > metal work (tray, channel, etc.) and piping > cable pulling > equipmentinstallation.

Penetration and embedded components start with the structural works. Piping underneath the ceilingand along the wall starts with the brickwork.

8 Standard Design Procedures

Note: the commencement of design may be earlier than the award of contract by 2m.


3/40

9 Standard Completion Stage


4/40

10 Standard Procedures for Material and Shop Drawing Preparation, Submission and Approvalfor Architectural Works


5/40


6/40

11 Standard Procedures for Material and Shop Drawing Preparation, Submission and Approval

for M&E Works

Concept

Define Resource under "Data" Apply Resource to an activity

Resource Unit Manhours or "Hrs" in short

Resource Production:

1) Rate: Unit per day (Hrs/d)

2) Budgeted Quantity Hrs

Resource Limit Hrs / d

Resource Price:

1) Rate: $ / Hrs

2) Budgeted Cost $


7/40

Example

Take sample file "APEX" for instance. Activity ID AS310 and description Site Preparation.

Resource Name: FLD EN3Limit: 8 Hrs / dPrice: $17 / Hrs

Unit per day: 4 Hrs / dOD: 10dPercent Complete: 80%

Scheduling

Resource

Cost


8/40

Resource Profile

Resource Usage

Resource Limit

Earn Value

Earn value for resource: BQWP=Budgeted Quantity for Work Performed=Actual to date(resource)

Earn value for cost: BCWP=Budgeted Cost for Work Performed=Actual to date (cost)

Resource and Cost Applied to an Activity

One activity can be applied more than one resource and more than one cost account.

Baseline

Baseline=Base Plan=Target Plan


9/40

1. What is Activity Movement Chart?An Activity Movement Chart is a diagram to present activities in general and easy-reading way. Its X-axisrepresents the geometric location and the Y-axis represents the time. An example of extraction of anactual Activity Movement Chart is something like this.

2. Planning BlockA Block is a working unit or basic resource allocation unit. Look at the typical Block below.


10/40


11/40

3. Group of Block---To Cover the whole structure


12/40

4. Network CPM---Another Way to Present LogicIn classic network, an activity has two predecessors, one is technical or work sequence control (hardconstraint), the other is resource control (soft constraint). An example is below. Comparing with ActivityMovement Chart, the former is the same, but the latter is different. In order to have concordance,practically, we have to control the start and finish point (key dates) of the group of blocks to make the twothe same timing.


13/40


14/40

1. What is called "Cost Load"?"Cost load" is to apply Budgeted Cost to the required activities with necessary cost account andresource. It is another version of BQ and used for progress payment.

2. Under Primavera: Export .wks fileUnder Content: Select the fields to be exported to Excel.

Under Format: Set the .wks file location and file name (no extension). Sorting is the same as theprogramme.


15/40

Under Selection: Filter to have desired data to be exported.


16/40

3. Under ExcelStep 1: Open .wks file

Step 2: Save as .xls fileStep 3: Cost load to the .xls fileStep 4: Save as .wks file (overwrite the previous .wks file)

4. Under PrimaveraBefore importing the data, Budgeted Cost under P3 must be "cleared". Otherwise, run Global Change todelete all Budgeted Cost data.


17/40

5. Under Primavera: Import .wks file


18/40

Note: by experience, a bridge Excel sheet is needed to link BQ and


19/40

1. What is Tabulation of Cost by Activity?It is a table extracted from the P3 programme to show all activities with cost load. It is used to evaluatethe tender breakdown price. An example of extraction is below.

2. Under PrimaveraExport .wks file.Under Content: specify the fields to export.


20/40

Under Format: Specify the .wks file location (filename must be in 8 characters) and sorting sequence(same as the programme).


21/40

3. Under ExcelOpen .wks file and save as .xls file.Add titles of the activity group and subtotal, grand tota


22/40

1. What is Tabulation of Cost by MajorItems of Work?

It is a table extracted from the P3 programme to show the summary activities with cost load. It is used fortender evaluation. An example of extraction is below.

2. Under PrimaveraGo to Tools > Tabular Reports > Matrix > Resource / Cost.

Under Content: specify Budgeted Cost as the data item. Resource is: direct, indirect and provisi(defined and cost loaded to activity)


23/40

Under Format: indicate Display column totals and Display row totals.


24/40

Under Sort: order shall be the same as the programme.


25/40

Under Selection: a standard filter.


26/40

Choose to generate the report and see on screen. Save the report as rich text file (.rtf). Copy the file tothe Excel.

3. Under ExcelTidy up the pasted file.

Sometimes, may generate more than 2 files and join them under excel.


27/40

1. What is Tabulation of Cost by Calendar Month and Projected Cash Flow S-Curve?It is a table showing monthly interim payment. It is used for tender and financial evaluation. An exampleof extraction is below.

S-curve is simply a graphic representation of the table.

2. Under PrimaveraGo to Tools > Tabular Reports > Cost > Tabular.

Under Resource Selection: Specify Direct, Indirect and Provisi (defined under Data > Resource and

cost loaded to activities).

Note: You need to add a fresh tabular report instead of modifying from the existing one.

Under Selection: able to pipe out which part of activities to have S-curve.

Under Timescale: select Early and Late dates S-curve respectively. Indicate the location of .wks file tobe exported. Timescale unit is month.


28/40

3. Under ExcelOpen .wks file and save as .xls file. Tidy up and capture other factors which the programme does notconsider them, such as advanced payment and payback installment, claim retention, duration of paymentcertificate.


29/40

PLANNING CYCLEThe following chart illustrates the general project cycle. Progress measurement is afterthe programme baseline is established and approved by the Client. The project progress is then to bemeasured based on the baseline.

WAYS OF MEASUREMENT

There are many ways to measure the progress from different perspectives; each has its merits andshortcomings. Agreement among all parties, especially the Client, must be reached before the progressmeasurement can start.

The list below is just a few often-used methods: By time lapse (progress in linear with original duration) By physical work done (no. of piles, penetration of sheet pile, concrete volume, etc)

By resource usage (actual manhour Vs. budgeted manhour) By money spent (progress claim or certified payment Vs. budgeted cost) By weightage (earned weightage Vs. planned weightage)

WEIGHTAGE A COMPREHENSIVE INDEX FOR PROGRESS MEASUREMENT

The preferred way is the weightage the artificial points assigned to activities (under P3 resource), forwhich we can balance different parts of the programme by assigning agreed percent of points. In otherwords, activities taking more time to complete, or requiring more manhour, or huge sum of moneyincurred to achieve the event, shall be assigned more weightages. In actual work, the original durationcan be initially used as the weightage and then adjusted later on.


30/40

Example 1: The major area of work is assigned the weightage (total weightage shall be100%). Completion percent times the weightage is the earned weightage. Total earned weightage is themeasurement of the project progress.

Example 2: Major trades of work is assigned the weightage (the figure is immaterial. The importance isthe proportion among all trades). The weightage of a trade over time period is distributed bythe programme. The distribution may consider some standard distribution pattern.


31/40

EARNED VALUE

Earned Value=Completion percent as of report date x Original value.Value can be:

Duration Quantity Efforts made (man-hour) Budgeted cost (money) Weightage

Note: the classical definition of the earned value is measured through money, that is, earned value=%completion x budgeted cost.


32/40

S CURVE CUMULATIVE EARNED VALUE AGAINSET PROJECT PERIOD

S curve is just the graphic representative of the cumulative earned value against the time lapsed. Theearned value curve, for a typical project, shall travel between the early and late planned curve, indicatingthe progress is on the track

From the S curve, one can technically measure how much the progress is ahead or delay.

PROGRESS LINKING PAYMENT

Traditionally, the payment is based on itemized BQ. The shortcoming of this way is that BQ does notreflect the site progress directly. BQ and site sequence of work do not align the same way.

To solve the problem, cost can be input into P3 baseline. If the cost is assigned to an activity (underdata->cost), the programme becomes the so-called cost loaded bar chart. Though each activity is notone-to-one pointing to the BQ item, the Level 4 heading under P3 can be rolled up (sum of earned value)and mapped to BQ item. The other way is using the costing coding (customized item under P3) to linkthe activity to BQ. See an example below (CTS is the customized coding system for linking the activity toBQ).


33/40

WEITAGE UNDER P6

1) Define resource as "C935 - Wtg", for example, non-labour type, with unit/time=1/d, price/unit=$0/h;2) Assign resource to activities (no assignment to duration=0 activities). Default budgeted unit equalsduration after first assignment (because of defined resource unit/time=1);3) Export "resource assignment" to Excel. Filter="C935 - Wtg". Sorting=activity ID ascending (act ID isimportant here. Otherwise, difficult to sort out the different part ofprogramme after exporting. Act ID

should be sorted out in ascending order when scheduling);4) Copy and rename the Excel file and balance weightage points under Excel to the different partof programme;5) Copy back the adjusted budgeted units to the original Excel file, under budgeted unit column;6) Import back the modified Excel file to P6.


34/40

Do you play shares? Share analysis usually applies two methods to analyze a particular share:fundamental and technical. Fundamental concerns the stock value, that is, whether it is worthy buying it;while the technical uses various kinds of chart to determine whether the good counter picked up by thefundamental analysis is the right timing to buy or sell the price is alright or not.Construction claim, to some extent, is similar to share analysis. The conditions of contract, specification

and all written documents are fundamental aspects to see whether there are grounds to raise the claim.The approved baseline programme, or CPM analysis, is to determine how much a contractor is entitled toclaim, especially when comes to EOT (extension of time) claim.The following are some pointers to consider:- Is the change belonging to owner side or contractor side? And if mixed, how much belonging to ownerside, and how much to the contractor?- To what extent the scope of work has been changed? Calculate the volume.- What is the effect the delay contributing to the critical path and how much with reference to theapproved baseline programme?Typically, a "Notice of Claim" shall be submitted to the Engineer within the specified days after the event.

The subsequent full and detailed claim documents shall be followed afterwards.In order to build up the claim case, a good and systematic document repository is to be set up from dayone of the project. Ideally, the project document repository shall be centralized and not segmentedaround a few departments and personnel. There are two benchmarks to be established from which theclaim is based on:- All information including specifications, drawings, tender clarifications at the tender stage and before thecontract is awarded. Anything beyond those which an experienced contractor can not foresee at the timeof tender is considered variations- Production rate before disruption. The approved baseline programme is based on the normal achievableproductivity. If an event occurs and causes the delay of progress, the post-event actual productivitysuffered by the contractor can be demonstrated with the "cause and effect" chart.Schedule is the tool to quantify or measure the delays and disruptions. There are two types of schedulesfor this purpose: conventional statused programme (updated programme in the approved baseline,showing plan and actual activities of bar by bar comparison). This method requires relatively accuratebaseline programme in order to serve the purpose. In reality, there is always work sequence deviationbetween the plan and actual and sometimes the deviation is too severe to reflect the actual construction.Revising the baseline is one solution. The other one is called "Forensic Schedule Analysis" or"Retrospective As-Built Schedule Development", a schedule modelled based on the actual construction. Itcontains:- Breakdown of the project into several process modules- For each process, establish the typical actual schedule model (fragnet). It shall reflect the actualconstruction sequence and represent the majority of this process- For each data date (for example, end of each month), retrospective schedule = baseline + fragnet(replacement of the correspondent part of the original baseline)- Status the above programme- Find out from the retrospective schedule:> Projected project completion at that time> Critical path at that time> Which activity causes the delay and how much


35/40

The final retrospective schedule represents the normal and non-disruptive work sequence with the actualtypical productivity. It is then used to measure the actual site works.The Contractors claim team comprises the following personnel:- A lawyer who is familiar with the construction industry to act as the advisor- The commercial manager who is the head of the team

- The coordinator to integrate all aspects of information and efforts, from site operation team to varioussite records- Event report writers- Planners to work out time impact- QS to work out cost impact


36/40

1 Plan Component1.1 Design Extract Main grid line

Boundary line Basement line

Building outline, lift core wall, major columns, shear walls, void, access, staircases

Overall dimension

Surrounding public roads

Drawing scale, true north direction

1.2

Major PlantLocation of tower crane, passenger hoist, concrete pump, etc.

1.3 Site Access Temporary decking, if any

Temporary gate

Guardhouse

1.4 Temporary Facilities RE, COW office

Contractor, sub-contractors office

Storehouse

Toilet for staff and workers

Canteen

Steel bending yard

Carpenters shed

Car park1.5 Temporary Utilities Water supply along perimeters of the hoarding

For site surface water control, no direct silt discharge to the public drain will be allowed. Instead,temporary drains will be constructed along perimeters of the site to flow into silt traps before


37/40

discharging into the public drain. Water from washing-bay will also be directed to the silt trap before

discharging into the public drain.

2 Site Transportation2.1 Vertical Transportation Tower crane Passenger hoist

Working platform

2.2 Horizontal Transportation Lorry

Loader

Tipper

3 Tower Crane3.1 Statuary Requirement PE design is required. If within airline corridor, there is height limit and the relevant authority approval

is required.

Normally, the radius shall be limited within boundary line, especially not beyond the public road.

3.2 TypeThere are two types of T/C: hammer type and luffing type. The latter can have more lifting capacity,

flexibility and hence, more expensive.

3.3 Jib Length and Counter Weight LengthNormal jib length is:

Hammer Type: 40m, 45m, 50m, 55m.

Luffing Type: 40m, 45m, 50m

Counter Weight Length:

Hammer Type: 16m

Luffing Type: 8m

3.4 Tip LoadNormal tip load is: 2-ton, 2.5-ton, 3-ton, 3.5-ton, 4-ton

3.5 Points of Arrangement The tip load shall be able to lift the heaviest component, eg. tableform, precast wall.


38/40

The coverage shall take care whole site area

The number of tower crane shall consider the working load. For example, precast structure, steelstructure needs more lifting capacity compared to normal RC structure.

The neighbouring tower crane shall maintain certain safety distance so that the jib of one T/C will nothit the other T/Cs mast. The height of the two neighbouring T/C shall maintain different.

Foundation of T/C shall avoid the location of the facilities, for example, sump room, substation room,etc.

Timing to construct the foundation of T/C shall be concurrent with the main structure. There is alwaysa time lag when the job site starts excavation and the T/C has not yet been installed. Mobile or

crawler crane is therefore needed for this period.

3.6 Standing Height and Tie-Back Maximum self-standing height: about 40-m (about 10 storey)

Tie back to the structure: every 4 or 5 storey3.7 Dismantle3.7.1 Dismantle Timing About 2 months after completion of roof structure and installation of M&E equipment on roof

3.7.2 Dismantle method Self lower down. This method requires the space for the jib to lower down

Use of mobile crane / derrick crane to help dismantle it. This method requires about 3 x 10-m spacefor an mobile crane to launch dismantling work

4 Crawler Crane and Mobile Crane Crawler Crane: 35-ton, 50-ton, 70-ton, 80-ton, 100-ton. For 50-ton, the maximum height is 58-m

Mobile Crane: 20-ton, 30-ton, 50-ton. For 50-ton, the maximum height is 50-m.

5 Passenger Hoist and Working PlatformWhile tower crane is mainly for the structural construction, the passenger lift, goods hoist and goods

platform are generally used for architectural and M&E works. Usually, when the building is more than 10-

storey and 4-units per block, the use of hoist is economical. Otherwise, only steel platform is to be used.

Whether using hoist or not, platform is always required for transporting wet trade material such as bricks,

sand, cement, etc. to the floor. Passenger hoist is mainly for transporting workers and dedicated material

such as tiles, marbles, pipes and M&E fixtures.

When to install

When the structure goes to 4th

or 5th

storey, the wet trades are going to catch up. And the vertical

transportation is required.


39/40

6 Estimated Rental Cost (2001)6.1 Tower CraneTake a 10 Storey building for example.

Hammer Type: S$8,000/month

Luffing Type: S$10,000/month

6.2 Crawler CraneTake 50-ton crawler crane for instance: S$5,800/month.

6.3 Mobile CraneTake 30-ton mobile crane for instance: S$450/day.

6.4 Passenger HoistTake twin-cage, 1.2-ton or 1.4-ton and for a 10-storey building for example. The rental is about S2,

400/month. For 2-ton type, it is S$2, 800/month.

7 Access7.1 RouteThe main site access shall normally follow the permanent fire engine access route. The crusher-run road

base is laid for the temporary as well as permanent purposes. Hoarding is to follow the boundary

line. Temporary utilities (electrical, water supply) follow the hoarding route.

7.2 Gate Facing the main road

Have nearby public drain for discharging water from washing bay (after being treated with silt trap)

8 Temporary Site Facilities

8.1 Welfare Facilities A canteen shall be provided if the number of workers exceeds 40

Sanitary facilities shall be provided separately for the sexes in the ratio of 1 water closet, 1 showercloset, 1 wash hand basin for every 25 workers. In addition, a 600-mm urinal shall be provided for

every 25 male workers or less. These toilet facilities shall be connected to a sewer / temporary septic

tank with the approval of Sewerage Department.

8.2 Container OfficeStandard container office available: 10 x 30 (3m x 9m), 10 x 40 (3m x 12m)


40/40

planning practise

Documents