Challenges of bored tunneling work

February 18, 2019

One of the greatest challenges for tunneling work is the unpredictable nature of the ground and hence it is not uncommon to see delays in tunneling work. The ground is non-homogeneous but actually stratified with different soil types. The soil condition can change abruptly along the tunnel alignment, hence the behavior or soil movement can be difficult to tell when tunneling through. Faced with this unpredictable nature of the ground, the tunneling rate is also difficult to forecast.

In this article, I will dwell into the various challenges encountered in boring tunneling projects.

Geology and Hydrology

In the case of mining through porous soil with high water table, a huge amount of groundwater can be drawn out during tunneling work. The sudden loss of a huge amount of groundwater can cause ground settlement, thus destabilize nearby structures to the tunneling work. Hence, tunneling along the ground with porous soil and high water table needs to slow down to grout the leaking zone and installing of re-charge wells to compensate for the loss of groundwater.

At times where the TBM is stuck in water-bearing soil or adjacent to the water body, then CHI has to be done under compressed air mode which is something tunnel engineers will like to avoid.  Doing CHI under compressed air is a dangerous affair as the crews have to work in confined space under high compressed air mode.

Progress of tunneling can also severely slowed down when passing through soils with varying ground conditions such as faults, weakness zones or soft soil combined hard rock. This is commonly known as mixed-face conditions.

In the case of unstable soil condition in front of the cutter head, during mining, TBM machine can get stuck. Stabilise the rock surface underground can take months before resuming the mining work, albeit slowly.

During tunneling, ground settlements or soil movement may happen which can severely affect the integrity of the structure above the ground. Hence, it is important to take precautions before the TBM passes under or near any of these structures.

Underground Utilities and structures

Prior to tunneling, the structures at the vicinity of the tunnel alignment has to be studied closely. In the case when tunneling near the tunnel of MRT tunnels, permissions have to be sought from relevant authorities.

A pre-con survey needs to be conducted on the nearby building to check the integrity of these structures priors to the Tunneling. Also, instrumentations need to be installed on these buildings and grounds along to monitor the impact on the building and surroundings during tunneling. At times, measures such as installing of recharge wells to prevent excessive groundwater loss or soil improvement such as Jet Grout Piling (JGP) needs to be carried out to stabilize the ground or probing/reinforcing the structures r may need to be done before and during tunneling work.

Choice of TBM

The geology of the ground affects the choice of TBM. In Singapore where the ground is non-homogenous, 2 types of shield TBM are commonly being used namely the Slurry TBM and Earth Pressure Balance Shield (EPB TBM).

For Slurry TBM, the excavation face is supported by pressurizing bentonite in cutter head chamber. Circulation fluid flushes out the muck. For EPB TBM,  the excavation face is supported by pressurizing soil inside the cutter head chamber.

The relationship between the soil granularity of the soil and the choice of  TBM  is as shown below.

Downtime and operation of TBM

The  productivity  of the TBM depends on minimising the downtime of the TBM. Downtime of the TBM can be due to:

  • Frequency of Cutter Head Intervention (Planned and Unplanned)

Due to the wear and tear of the cutter heads, it has to be replaced every now and then. In the case of planned CHI, after certain specified length of tunnelling, the operation of the TBM is halted for replacing the cutter heads. This specified length is a function of the cutter head’s specification and the hardness of the ground. In the case where the ground is more abrasive, then the cutter heads need to be change more frequently.   In the case of unplanned CHI, the cutter heads need to be replaced before the planned CHI due to far worse  anticipated abrasive soil conditions.

  • TBM break down

Just like driving a motor car on the road, the TBM can break down due to failure in the TBM components.  The frequency of breakdown tends to increase with the duration of the TBM service.

  • Delay in the delivery of PC Segmental linings

Due to poor logistic planning, the PC Segments can be delayed from reaching the front of the TBM for installation. Delays can be due to the slow production of the segment, break down of back-up cars that carries the PC segments into the tunnel, breakdown of gantry cranes that lower the PC segments into the tunnels or poor productivity of crews.

  • Disposal of the mined material/Efficiency of Slurry plant

For EPB TBM, the disposal of mined materials is done by muck-up trains or by conveyor belt transversing between the TBM and the shaft. Then the mined materials are being lifted up to the ground surface by a gantry crane or using a clamshell bucket if the shaft is not too deep (less than 30m)

If the disposal of mined materials do not pace with the tunneling, then the tunneling rate will hampered.

At times, due to lack of space to dump the mined materials, the operation of TBM has to be suspended.

In the case of slurry TBM,

priors to disposals of soils, the mined material has to be treated in the slurry plant. When the slurry plant choked up, the operation will be halted.

Alignment of the tunnel

Alignment of the tunnel can also influence the tunnelling rate of the TBM, During negotiating curve, the tunnelling speed needs to be slowed down. This is similar to negotiating curves while driving a car on the road.

In  Singapore Cable Tunnel Projects, to minimize tunneling disturbance to buildings above, the tunnels were being built in underneath and along the carriageway. Due to this constraint, some of tunnels alignment between Kallang Equipment Building and Paya Lebar Ventilation Building had the tightest curves (75m radius) for a 7m diameter TBM to date in Singapore.


It is important to take study the geology profile of the bored tunnels in detail when developing the project schedule. It should never develop a schedule with an assumed uniform rate. The bored tunnel activities should be developed in greater detail in corresponding to the geology/hydrology of the ground. Based on the geology/hydrology of the ground, the tunneling rates should also factor in the frequency and duration of Cutter Head Intervention.

With the anticipated tunneling rates, it is important to ensure there are enough workers and resources to dispose of the excavated materials and delivery of PC segments. In the case of slurry TBM, the sizing and operation of the slurry plant are very important so as to ensure the smooth mining of bored tunnels.

Things to look up for when reviewing updated construction schedule

January 17, 2019

Compounding on the earlier topic about why Project Managers don’t review updated construction schedule, I will like to share with you guys ways which you can review the updated schedule effectively in managing your project.

A level 3 updated construction schedule is a very detailed schedule comprising of thousands of activities. Unless you have Primavera P6 /MS Project reader to open the native file and know how to filter the activities, it is very difficult to read and understand the project schedule. However, does it mean that without the native reader for Primavera P6 or MS Project, you cannot review the schedule? Absolutely not.

One way is to request the project planner to filter the activities in various specific layouts and save schedules in PDF format for review or you can get the project planner to filter the activities and review in front of you and your project team.

Let’s go into the various filter layouts when reviewing the schedule.

Check progress percentages and corresponding start and finish dates

Before diving into Critical Path Analysis to see which are the critical activities leading to the various completion milestones, it is important to ascertain that the progress updates (Actual Start, Actual Finish Dates, progress percentages ) are correctly input. There is a saying

“Garbage in, Garbage out”.

If the update is incorrect, any analysis is meaningless. The forecast finish date of each activity is calculated by the scheduling software as follows:

Remaining Duration = Remaining percentage x Original Duration
Expected Finish = Scheduled Data Date + Remaining Duration

To check if the progress percentages of these ongoing activities are correctly updated, all these activities should be filtered.  In this layout, a column showing the previous corresponding percentage update will be useful for comparing the current progress against the previous update.

 It is definitely helpful that activities are being validated  against the daily site reports.

It is important that the percentage of the activities are captured correctly in each update so that:

1) The updated schedule correctly reflects the status of the project

2) The updated schedule is the basis for Time Impact Analysis during EOT evaluation

Check the programme logic for 4 weeks look ahead

Next to be examine is the 4 weeks look ahead activities. The project team should check the 4 weeks look ahead activities are still valid, considering the site condition.

However, activities that ought to take place within the next 4 weeks  may be missing from the “4 weeks look ahead “window.  There are 3 possibilities for this. Firstly, the “missing” activities are not in the schedule at all as it has been overlooked during the baseline submission. Secondly, there are errors in the upstream programme logic of these missing activities such that it pushes these activities out of the 4 weeks window. Thirdly, the “Retain Logic” Option is being selected for scheduling. When the actual sequence of activities are not in the same order as originally planned, the “Retained Logic” will push the downstream activities which should have taken place in the next 4 weeks window beyond.

There are some controversies in the scheduling community on whether the programme logic should be allowed to change to reflect the actual intent sequence of work on site during progress updating. On the other hand, some argued that by changing the programme logic, it is no longer reflective of the original intent of work sequences, thus making the evaluation EOT difficult.

Different organisations have different practices in allowing changes in programme logics and in the choice of scheduling options. May I hear your views here on the pro and cons of the various practices?

Arrange the activities by Total Floats

Critical path is the longest path of the project and hence determines the completion date of the project. To see the critical path, the activities shall be grouped by total floats. Activities with the biggest negative floats shall be reviewed first to identify the most critical activities. From these critical activities, the cause of delay shall be examined and catching up measures can be discussed.

Also do note those with excessive total floats. It can also mean that these activities are not properly linked or not linked at all.

In summary, a properly updated project schedule can be very useful tool for the project manager to ascertain the project status, identify bottlenecks and brainstorm for solutions.

What so difficult about Interface management?

January 10, 2019

Interface management plays a large part in the success of managing a project. Without proper interface management, it can cause overall project to delay and cost to over run.

In construction project, there are much interface works with adjacent contractors, sub-contractors, systems wide contractors and external authorities.  Let examine some of the challenges in interface management.

Scale and Complexity of the project

One of the reasons managing large scale project is more complex is not just because the physical quantity of work is larger, but there are also more parties being involved.  Hence with more parties involved, the complexity of interfaces increases.

In a mega project, project is broken down into multiple main packages. In addition, many major trades will be appointed by the client directly and novate to the main contractors later, so as to save cost through bulk purchase and standardisation of equipment. As such, main contractors not only have to manage lateral  interfaces with the adjacent main contractors but also vertical interfaces of sub-contractors.

Inconsistencies in tender/contract documentations

It is not uncommon to find discrepancies in contract documentations between different contract packages. In one case, the nominated sub-contract stated that the duration of installation and testing of lifts was 4 months. However, in the main contracts, the duration for lifts  installation and testing allowed for only 3 months. Just imagined if you were the nominated sub-contractor, would you agree to a shorter duration upon novation to the Main-contractors?

In another example, the drawing details of the interface between adjacent contractors differed. Either contractors would not agree to change their own design as they were doing according to the required specifications. In which case, the Engineer had to issue EI to regularise the inconsistencies.

Lateral interface management.

Lateral interface refers to adjacent contractors sharing common interfaces. They don’t have direct contractual obligation with each other.

One of the common issues of lateral interfacing is sharing of access or providing of access to his adjacent contractor.  In one of my project, my contractor could not delivered materials into the bored tunnel from our side as the opening had been closed. As a result, my contractor needed to deliver the materials through the shaft opening of the adjacent contractor. As the delivery would affect their adjacent contractor’s work and there was no stipulated clause that the contractor needed to provide free access to the adjacent contractor , it took quite an amount of effort to interface and coordinate among the contractors. At times, it required the client PMs to step in to facilitate the coordination.

Other common issue of lateral interfacing work includes managing common access of the adjacent contractor to carry out their work.

In the interface zone, when there is a shared boundary or overlapping of work,  the boundary’s scope of work can be muddy. This may result in the adjacent contractors doing nothing in this interfacing zone as both contractors thought that it is the other party’s obligation.

For M&E work, it is not practical to terminate the utility work such as piping/cabling exactly at the boundary line. Hence the termination of M&E services may encroach into the other contractor’s boundary.

Vertical Interface management

In the case of vertical interfaces, the downstream contractors work depends on the successful handover of work from the upstream contractors.  If the upstream contractor cannot fulfilled his contractual obligation on time, then it has a knock off effect on the commencement of downstream contractor’s work.  

M&E systems integration

There are many M&E systems in a building which are managed by different vendors. There are much software and hardware components between systems to be integrated. Some systems adopt open standards while some systems adopt proprietary format. Hence interfacing and integrating of systems can be quite challenging and time consuming.

I saw many times the main contractor underestimate the complexities of systems integration and it took much longer time to troubleshoot and fix the faults during integration testing than planned.

 It is imperative that overall systems architecture be clearly defined and systems boundaries demarcated. Otherwise, time can be wasted on abortive work, troubleshooting and fixing the issues during testing and commissioning.


In summary, interface management needs careful consideration. It is important to realise this as one of the project risks and to manage it closely and timely.               

About the Author:

Stanley Tey has more than two decades of project management experience after graduating from the National University of Singapore in Civil Engineering. He also obtained a Master Degree in Software Engineering from Institute of Systems Science, NUS where he specialized in Project Management and Systems Integration.

He has worked as a Consulting Engineer, Project Planner, and Project Manager. Some of the projects he had handled are:

  • North East Line
  • Singapore 1st Desalination Water Plant at Tuas
  • Integrated Resort Project at Sentosa
  • Lonza Cell Therapy Plant at Tuas (Phase 2)
  • Merck Junumet plant at Tuas
  • Singapore Special Cable Tunnel Project

Why Project Manager don’t trust the project schedule

January 4, 2019

Many project managers do not read the updated project schedule. I know many people (project managers and project planners/schedulers are going to feel indignant about my statement above.

But hang on, before you jump at what I said above, let me explain how I derived at this conclusion and why Project Manager doesn’t read the schedule before submission.

As a client Project Manager, I received the monthly progress schedule which was attached as appendices of the monthly report. More often than not, I noticed that the activities were not correctly updated. For example, certain activities were updated as completed but in actual fact, it was not yet completed and vice visa. Obviously, if the PM had reviewed the updated schedule, he ought to have caught all these glaring discrepancies!

 Of course, for those activities that were in progress (not updated with 100% completed), it was difficult to say the updated percentage was incorrect from the updated schedule alone. There was always a degree of subjectivity when it comes to percentage updating. How to tell to tell with certainty if the updated activities should be 40% and not 30%?

So my conclusion was, the updated schedule was hardly reviewed by the PM before being submitted.

Wasn’t the updated schedule an important artifact and a basis for EOT claims evaluation when Time Impact Analysis would be performed? How would it affect the total floats and validity of the critical path if the schedule was not updated properly?

Now let us examine the root cause of why the schedule was not always updated correctly.

  1. There were thousands of activities in a baseline schedule. It was unlikely that all dependencies between activities could be validated by the contactor’s team members. Likewise, the client’s project team could not have caught all the errors in the programming logic during the review, except for very glaring errors.
  2. There was no agreed basis on the computation of percentage completion before the schedules began updating. For example, when the activities for slab casting was updated as 40% completed, did it meant 40% of the slab cast or rebar work? Was there an establishment of weightage for the sub-activities work?
  3. Scheduler/Planner did not know what they are updating!. Once, I asked the contractor’s scheduler/planner what that M&E activities were referring to and why it was updated as such. His reply was, he did not know exactly but his M&E manager told him so!
  4. The logic of project schedule was not updated accordingly with site development as work progress. Site development was very dynamic and the intended changes in the sequence of site work were not updated accordingly in the schedule. I was not sure if the changes of logic were not changed due to ignorance of the project planner/scheduler or because of the schedule control mechanism did not the logic of the programme to be changed until it was being approved or any other reasons.
  5.  As such, for the above reasons, PM did not trust the updated schedule. Also, it was very tedious to look at the schedule that runs into thousands of activities. Rather he would gauge the progress of the project by looking at site progress in relations to the milestones set in the baseline schedule.

In conclusion, I will urge the planners/schedulers to review the updated schedule with your project manager and team members regularly. It is very important to walk the site and know what is happening on site. Try to establish the basis of percentage updates for major trades with the team package leads and the subcontractors. Last but not least, do not be shy to ask the team leads about the progress updates if in doubt.

About the Author:

Stanley Tey has more than two decades of project management experience after graduating from the National University of Singapore in Civil Engineering. He also obtained a Master Degree in Software Engineering from Institute of Systems Science, NUS where he specialized in Project Management and Systems Integration.

He has worked as a Consulting Engineer, Project Planner, and Project Manager. Some of the projects he had handled are:

  • North East Line
  • Singapore 1st Desalination Water Plant at Tuas
  • Integrated Resort Project at Sentosa
  • Lonza Cell Therapy Plant at Tuas (Phase 2)
  • Merck Junumet plant at Tuas
  • Singapore Special Cable Tunnel Project

Do you Insource or Outsource project scheduling work in your company?

January 2, 2019

More and more contractors are indirectly hiring project planners/schedulers and choosing to insource project planners/schedulers from third-party outsourcer or outsource the service of project scheduling to a consultancy firm like Pro1plan Consultants.

There are many advantages in insourcing/outsourcing project scheduling as listed below:

  1. Project scheduling is seen as a utility and non-core business of the project. It is akin to Autocad drafting, surveying, and legal services. It can be substituted and replaced easily.
  2. Except for big projects, it is not a pre-requisite for smaller projects to use CPM scheduling tool such as Primavera P6 for project scheduling.  The use of MS Excel or MS Project is sufficient for most smaller construction projects. However, when submission of project schedule using Primavera P6 is necessitated for project tendering,  it is cheaper and faster to get a scheduler from a third-party provider for short term. Furthermore, there is no need to buy Primavera P6 Licence or send staff for P6 software training.
  3. It is difficult to recruit and retain bright and ambitious young professionals in scheduling function for long in a company.
  4. Project scheduling requires specialized knowledge of project schedule planning and project control. It is not just the mastery in the use of software scheduling tool, it takes time to master the knowledge of project planning and scheduling.

Insourcing and outsourcing each have its advantages and disadvantages. For insourcing,  the planner/scheduler is at the full disposal of the project as he works full time. The disadvantage of this arrangement is it is difficult to get good quality planner/scheduler from the “body shop”. Most of these planners/schedulers are young with limited work experiences as these “body shops” cannot get qualified planners/schedulers with enough site experiences. They work merely as software operators or programmers.

Once I spoke to the boss of a “body shop” and he lamented that he could not pay the project planner/scheduler well because contractors were not willing to pay more for the services his company rendered. He could only get young project planners/schedulers from 3rd world countries with limited work experiences.

Next, we talk about outsourcing of project scheduling.  The contractor engages a planning consultancy firm to develop the project schedule. Typically, during the development of tender/baseline schedule, the planning consultant works full time on or off-site until the delivery of the project schedule to the client. He usually charges the client based on effort/days he spends to develop the schedule or by specified milestones such as the 1st draft, 2nd draft, and final submission. After that, the planning consultant may work on 1 to 2 days weekly on an ad-hoc basis for the remaining tenure of the project once the baseline schedule is approved. In addition, he can also render planning/scheduling consultancy service as and when is needed. As such, there is no fixed overhead and thereby achieving cost savings.

The advantage of engaging a planning consultant is he can be counted to deliver the project deliverables without any hand-holding. During the tendering phase of the project where there is no luxury of time, a planning consultant’s service is especially critical as it speeds up the preparation of tender schedule and other related tender documentation. He knows what to look up for in scheduling development and programme requirements through his vast experience in handling projects.

The disadvantage of this option is that the planning consultant is not employed on a full-time basis. Sometimes, communication may be via phone, email or SMS and may not be as effective as communicating in person. Also, his rate is more expensive on a per day basis. Again, the experience of consultants vary and sometimes may not be as good as claim. Prior to engaging the consultant, it is important to interview him and check his credentials.

In summary, whether to insource or outsource project scheduling/planning depends on the expectations and requirements of the project. Do you need a full-time scheduler/planner with limited work experience to operate the planning scheduling tool or a planning consultant on assignment basis where he can be count on delivering the schedule development but at a higher rate?

If you are working as a planner/schedulers, I will like to hear your views as well.

About the Author:

Stanley Tey has more than two decades of project management experience after graduating from the National University of Singapore in Civil Engineering. He also obtained a Master Degree in Software Engineering from Institute of Systems Science, NUS where he specialized in Project Management and Systems Integration. He has worked as a Consulting Engineer, Project Planner, and Project Manager. Some of the projects he had handled are:

  • North East Line
  • Singapore 1st Desalination Water Plant at Tuas
  • Integrated Resort Project at Sentosa
  • Lonza Cell Therapy Plant at Tuas (Phase 2)
  • Merck Junumet plant at Tuas
  • Singapore Special Cable Tunnel Project

Top down or bottom up for project schedule planning?

December 24, 2018

In PMBOK, a project life cycle comprises of 4 phases namely:


2. Planning

3. Execution

4. Closing out

Initiation phase (also known as Conceptual phase) of a construction project is initiated from the client side.  During this phase, a business case is being presented to the senior management. In this business case, the purpose of this project, the high-level description of the project, success criteria, the project budget cost and the high-level project timeline(Level 0) will be outlined. Usually, the timeline is estimated based on projects of similar complexity.

Once the project is given a go-ahead by the senior management, the planning phase of the project life cycle begins. The designated PM will proceed to develop a Project Master Schedule (usually Level 2) with inputs from Architect, C&S consultants, M&E consultants, contracts managers, and internal stakeholders. It serves as a basis on which the milestones and key dates in the tender specifications is being derived.

At the tender stage, each tenderer will be requested to submit a detailed tender programme to comply with the specified milestones and key dates in the tender specifications. To be shortlisted,  It is essential that the tenderers’ demonstrate their understanding of the project scope and ability to complete the project within the timeline of the project. Hence, the tender schedule is usually a Level 3 schedule which shows sufficient details of their intent sequence of works. To aid the understanding of the programme, it is normally accompanied by a programme narrative which describe the construction strategy, general sequences of work, assumed productivity of various trades, critical path, project constraints, associated project risk and how it will be managed.

Once the project is awarded to the successful contractor, the execution phase of the project commences. A detail baseline schedule (level 3) which is further developed from the tender schedule is being submitted for approval which when approved is being used for subsequent status reporting to the client and EOT evaluation.

However, for site tracking and controlling of sub-contractors’ work, each sub-contractor will further develop a more granular Level 4 sub-contract schedule based on their sub-contract deliverable milestones.

For site supervision, a very detail 1 week look ahead work schedule is further developed from the above Level 4 schedule so as to track and manage the day to day site work.

How long does it takes to develop a project schedule?

December 20, 2018

A project schedule is a listing of project’s milestones, activities with intended start and finish dates. It is normally in Gantt Chart format. If the number of activities in the project is small, it can be created with MS Excel. However, if the number of activities is large and need to be properly linked up to perform Critical Path Analysis, then the project schedule will need a proper project scheduling tool such as Oracle Primavera P6 or MS Project to create.  The duration it takes to develop the schedule depends on many factors:

Size and Complexity of the project

The greater the size and complexity of the project, one will expect more time is needed to understand the project scope and develop the project schedule.

Granularity of the schedule

The greater the schedule’s granularity, the greater the effort required to develop the schedule. Schedule granularity is classified from level 1 to 5. Level 1 being the least detail and Level 5 being the most detail. Level 1 schedule comprises mainly of key dates and milestones and it is usually meant for giving the audience an overall view of the project timeline. Level 5 schedule being the most detailed, it is developed by the contractor to track the day to day progress of site work. To ascertain the Critical Path (the longest path) of the project, there should be sufficient details in the schedule and a level 3 schedule is warranted.

Programme Specification

Some projects schedules are required to comply with the client’s programme/schedule specification. Such specification may specify the granularity of the activities such as the minimum and maximum duration of each activity. Some specifications will also specify that the activities of the project schedules be cost or/and resource loaded.

Programme Review

Project Schedule needs the buy-in from the project team and it has to be reviewed by the team. Hence the duration required for schedule development also depends on the outcome of the review and the subsequent amendments.

Experience of the project planner/scheduler

Last but not least, the experience of the planner/scheduler is very important. An experienced planner is not only adept in using the programme planning software to develop the programme, but he also has a good understanding of project planning and scheduling methodology, the full project life cycle and the domain knowledge of the construction industry.

A good planner/scheduler should have sufficient site and project experience so that he can appreciate the project scope and constraints; understand the project risks, the processes in procurement and design, authorities permitting processes, the construction sequences, interfacing work between trades, M&E works and T&C work.

Unfortunately, there are not many planner/scheduler out there who have sufficient site experience to understand the full project lifecycle development. As such, a lot of hand-holding is required and the project planner/scheduler is doing no more than a programmer’s job!

About the Author:

Stanley Tey has more than two decades of project management experience after graduating from the National University of Singapore in Civil Engineering. He also obtained a Master Degree in Software Engineering from Institute of Systems Science, NUS where he specialized in Project Management and Systems Integration. He has worked as a Consulting Engineer, Project Planner, and Project Manager. Some of the projects he had handled are:

  • North East Line
  • Singapore 1st Desalination Water Plant at Tuas
  • Integrated Resort Project at Sentosa
  • Lonza Cell Therapy Plant at Tuas (Phase 2)
  • Merck Junumet plant at Tuas
  • Singapore Special Cable Tunnel Project

Freelance Project Schedule Planning

December 17, 2018

Are you facing bottlenecks in developing Tender/Baseline programme in Primavera P6 or MS Project and related documentation such as programme narratives, labor histogram, Cost S Curve, Time Chainage Diagram due to a lack of experience project planner/scheduler during this tight timeline?

If your answer is yes, please read on.

Pro1plan Consultants offers cost-effective Project Planning and scheduling services, starting from tender, baseline schedule, through baseline revisions, progress reporting, resource loading, analyze schedule and recommend corrective action, Extension of Time and Financial Claims.

With extensive experience in project schedule planning and implementation for projects in MRT, Commercial, Water Treatment Plant, Integrated Resorts, Pharmaceutical and Cable Tunnels using Primavera P6 or MS Project, we can customize a solution to meet your requirements.

We will work closely with your project team at any stages of the project be it in the Feasibility, Tender, Construction, Fit-out, Commissioning or Closing Up phase of the project.

Please email us at or by phone at (65) 9817 6974 for an non-obligatory discussion.

Different perspectives of Project Management from contractor and client

December 7, 2018

In theory, the contractor and client have a common goal, and that is to complete the project successfully. But the meaning of”successfully” takes on a different interpretation depending on whether you are working with the contractor or with the client. Having worked with both contractors and clients, it enables me to see things from different perspectives from both sides.

As a contractor, the primary objective is to finish the project successfully with minimum cost and maximum profit. While I was with the contractors, I would not volunteer to give information to my client about the delay or the status outright especially if the delay was due to the contractor. However. when there were delays due to the client or third parties, I would make sure it would be documented and the client be notified within 14 days (depending on the provisions of contacts)about the delay. This would serve as evidence of delay for eventual claims for EOT.

As a contractor, one needs to know the project scope well as well as how to get it implemented. Do not do anything extra like “gold plating” for it will cost the company more money, for the client may come back and ask for even more”favor”.  If it is not in the scope, the contractor will request a Variation Order, before he will proceed with the extra work.

Being a contractor needs to be very diplomatic when dealing with the client’s request. Typically, when the client makes a vebal request for extra work to be done, the contractor PM will not commit nor reject the request outright.  Instead, he will say “Let me go back and think about it.”

As a contractor, one needs to control the sub-contractors and manage the client’s expectations. Do not over promise and under deliver!

Let me talk about being on the opposite side , i.e. the client side. The definition of project success is – complete on time with cost-saving against the budget. One needs to know the contract specifications and obligations of the contractor well. He needs to know what need to be done and when it should be completed. In my recent role as Project Manager, I paid close attention to the planning and site execution of work. A plan is not just a schedule! For a plan to be executable, there should be 5Ms.

  • Method Statement
  • Machine
  • Manpower
  • Materials
  • Management Commitment

Being with contractors before, I knew I cannot totally trust the contractor to tell me everything.  I requested the contractor to submit a rolling 2 months short-range detail programme where I will scrutinize together with the contractor, consultant team and my supervision team on the viability of the schedule and resources to be committed weekly.  This ensures the contractor commits adequate resources on site to move the job. It is important to track the progress closely. These days with What Apps, it is very easy to share and keep the team updated on a regular basis. I used to send photo and emails to the senior management of both client and contractor when there were not enough resources to move the job. it proved to be somewhat effective as it prevented contractor’s site team from slacking and served as evidence of delays due to their poor site management.

Another vital role of client’s PM is to ensure that the project is being built and fit for purpose. Many times, the contract specification is vague, incorrect or missing. Client’s PM needs to coordinate with internal stakeholders to ensure that Variation Orders are issued timely.

Sometimes, when there are delays due to third parties such as authorities agencies, the client’s PM has to step in to front the agencies pro-actively. For delays due to third parties, the contractor will be too happy to tell you, the delays are not due to them and they should be entitled to EOT.

In conclusion, a project success depends on all parties: – the client, contractors and consultants. There is a need to have check and balance. Everybody plays a different role and there will always be different interpretations of project success. 

About the Author:

Stanley Tey has more than two decades of project management experience after graduating from the National University of Singapore in Civil Engineering. He also obtained a Master Degree in Software Engineering from Institute of Systems Science, NUS where he specialized in Project Management and Systems Integration. He has worked as a Consulting Engineer, Project Planner, and Project Manager. Some of the projects he had handled are:

  • North East Line
  • Singapore 1st Desalination Water Plant at Tuas
  • Integrated Resort Project at Sentosa
  • Lonza Cell Therapy Plant at Tuas (Phase 2)
  • Merck Junumet plant at Tuas
  • Singapore Special Cable Tunnel Project

How to handle project delay

December 4, 2018

In construction projects, handling project delay is parts and parcels of a project. Some delay can be avoided, some can only be mitigated while some can only be managed.

I will like to discuss some of the cause of delays and measures to counteract delays based on my experience.

Tight Budget

In a tight market, contractors are hungry for the job and will dive for the job without considering the tight schedule in relation to the project cost. At the beginning of the project, he is already stuck with low or no profit margin. At one hand he has a tight schedule and a tight budget on the other hand. Due to the tight budget, he may not get the most qualified sub-contractors on board or take a longer time to negotiate the sub-contracts which lead to delay from the start of the project

With lesser qualified sub-contractors on board the project, he has lesser resources to carry out the work. When the sub-contractor is not able to perform as well as they should, it is too late or too expensive to change the sub-contractors.

Therefore, it is prudent to select the main contractor carefully and not award to the cheapest. There is a saying:

“Cheap may not be good and good may not be cheap.”

Unrealistic schedule

Another cause of the delay is an unrealistic schedule. As most PM are from the civil engineering background, they tend to pay greater attention to Civil and Structural work while neglecting the downstream M&E fit out, T&C and downstream activities while planning of the schedule. One of the misconceptions about M&E fit-out work and T&C work is, the schedule can be squashed significantly by putting more resources. No doubt, when fit out is being done indoors, it is to a lesser extent dependent on the weather. However, there is a still a limit to how much more time one can be shaved off by putting more workers or increasing the working hours.

To ensure that schedule is realistic from start, the tender specification should specify more milestones and key dates as “gates” so that in the events of slippages to these milestones and key dates, it can be flagged out earlier and take remedial action to recover the delay.

The baseline schedule needs to be reviewed carefully together with the programme narrative to ensure that the schedule is realistic taking into account the project risk identified, the resources and the tracking measures are in place.

Mistakes and changes in designs

Due to the hectic and complex nature of the project, design mistakes are only discovered during the construction phase. Other times, changes in design are not being effectively communicated between consultants. As a result, fabrication or construction work has to be reworked,

To ensure design mistakes or changes are minimized, adequate time should be provided to prepare and review the design by the consultants and clients representatives before a contract is being awarded.

Lack of transparency and use of critical path management.

Very often, the site work between contractors is not in sync with one another. The contractors carry their work in accordance to own preference and oblivious to other contractors’ work. There is a lack of site coordination to ensure adherence to the Master Project Schedule.  For instance, the area that is cast earlier by Civil Contractor may not one that is first needed by M&E contractor and on the critical path of the project.

Logistic and site constraint

In the event of concurrent works on site, multiple activities are carried out by different contractors. Logistic and space constraints are always an issue. For example, different contractors need the limited number of cranes or common access to bring in and out the materials. When these limited resources are not properly planned and utilized, the project can come to a standstill.

The contractor should ensure there is an adequate deployment of site coordinators for the project. There should be regular weekly detail planning workshops as well as regular updates of the working programmes. The 90 days look ahead schedules should be expanded and detailed with illustrations so that every person attending the coordination meeting understand what, when and how the activities will be carried out.

In addition, the daily coordination meeting needs to be attended by all contractors’ PMs and engineers to ensure that everyone understands what are the deliverable and the solve the site issues at hand.

Failure to keep a risk register and constant monitoring

Many contractors failed to verbalize the risk of delay of the project. Some of the delays are known “unknown” while some are unknown of unknown. Known “unknown” refers to delays that you know it could happen. Unknown “Unknown” delays refer to delays that it cannot have been predicted.

An example of a known “unknown” will be delayed due to unknown ground condition or long procurement lead time of some equipment. Knowing that all ground condition cannot be fully known based on bored log or geotechnical drawings given during the tender stage, the contractor should carry out more soil investigation prior to the commencement of work. Likewise, if some equipment requires long lead time, the contractor should source and proceed with the procurement of these items earlier and monitor the procurement of these items closely to pre-empt any delay to the deliveries of these items.

An example of unknown “unknown” delay is extremely bad weather. While we can’t say specifically when it is going to rain,  we can still factor in some duration for external work to take into account the unpredictable nature of the weather. However, there are years where there is an abnormally high frequency of rain beyond the expectation to the detriment of the project.

Lacking the understanding and underestimating the duration of Test and Commissioning Work

Many projects are delayed due to Systems Testing and Commissioning. Firstly most PMs are not M&E trained and they do not understand exactly what is involved in T&C phase. They thought that since the equipment has already done the Factory Acceptance Test (FAT), site T&C work should be very straightforward. But they are totally wrong!

FAT is done in the manufacturer factory and in a very “ideal” environment. However, testing on site is much more complex. Firstly testing is done after installation of the equipment on a “standalone” basis before connecting to other systems. After it passes the “standalone” test, it proceeds with the interface test with another system. After interface tests, then it is finally the integration test. During testing, various functional tests are done. At it can very time consuming to locate the faults as the fault can be within or beyond the system’s boundaries. Furthermore, with multiple systems suppliers and installers, it can be very daunting as each systems suppliers and installers will be pointing fingers at each other for the defaults or faults.

To ensure that T&C activities will not hold up the project, it is important that ample time ts being allocated for T&C activities, T&C engineers should be engaged early to prepare the T&C plan and provide a detail T&C schedule way before the T&C commencement.When drafting the scope of M&E systems contractors, try not to break into too many packages. For instance, for fire protection system, ideally, one contractor be awarded and be solely responsible for supply, installation, and commissioning instead of getting different vendors for different components of the fire protection system.

Failure to acknowledge the delay

Some owners, consultants or contractors frown upon open discussion and acknowledgment of project delay during progress update meeting to senior management.

For some senior management, they rather that you solved the problem than highlighting the issues to them. For the sake of pleasantry, they rather pretend it never happen and they want to believe that delay will just go away in due time. However, when it is finally acknowledged, it is already too late for any remedy.

I feel that the client’s senior management should not avoid the issue of delay. If the contractor has validity in entitlement for Extension of Time, it should be awarded accordingly and give instruction for acceleration work to recover the delay.

About the Author:

Stanley Tey has more than two decades of project management experience after graduating from the National University of Singapore in Civil Engineering. He also obtained a Master Degree in Software Engineering from Institute of Systems Science, NUS where he specialized in Project Management and Systems Integration.

He has worked as a Consulting Engineer, Project Planner, and Project Manager. Some of the projects he had handled are:

  • North East Line
  • Singapore 1st Desalination Water Plant at Tuas
  • Integrated Resort Project at Sentosa
  • Lonza Cell Therapy Plant at Tuas (Phase 2)
  • Merck Junumet plant at Tuas
  • Singapore Special Cable Tunnel Project