Monday, August 26, 2013

Risk management in Road construction

Risk management in construction is a field that should not be put aside by any contractor. Risk management is important to help us delivered the end product with in the stipulated time frame without lost or minimum lost in our profit margin and the most important is maintaining our good reputation.

Road construction,just like other construction work, it is prone to risk. Whatever risk that involve in construction, at the end of the day, it will count as dollar and cent. In-view of this situation, contractor have to find ways to mitigate this loses.

How to minimized and address this issue? Before we discuss any further, let's take a look at what is some of the scope of work involve. Below are some of the scope of work involve.

1. Earthwork
2. Bridge
3. Sub-base
4. Road-base
5. Tar seal ( ACB,ACW,Tack coat & Prime coat)
6. Road paint or Road marking
7. Guard rail & other road furniture
8. Street lighting.

As listed above, we can see there is eight(8) trades involve to roughly complete the road.Indirectly this information is telling us that we need eight specialist team. Then how to relate this with risk management? Here how to address this. Since we already know what trade involve, The next step is doing brain storming. This is important to identify any possible risk that will involve in each of the trade. This is basic rule of risk management. It will be impossible to come out with risk management plan without knowing what possible risk to take into account. The root to risk management is " what is the risk that we expecting to occur with-in those trade". Only by knowing what is the risk that we can start working the plan that is the best management or solution to prevent or minimized the risk.

Now let we look in to the earthwork trade. What is the possible risk that we have that will prevent us from completing this task as per required time frame as agreed in the contract. Let list down some of the possible risk.

Possible risk in earthwork.

1. Bad weather
2. Machine breakdown
3. increase in fuel and diesel pricing
4. accident
5. impact to environment
6. increase in cost of material

since we already know the possible risk that will affect the work, than only we can plan on how to manage the risk. As we know, if we allow the possible risk to take place or happened, it will resulted into lost of profit or even jeopardize our reputation, what we need to do is to lay a proper plan of risk management to address these event. For example, we look in to the bad weather (rainy day), first we better look at the number of days throughout the month of previous years. Do some calculation, find out how may days is raining day of the month of the previous years. let say it is average of 10 days. This simply mean that we have a risk of non-workable day of 10 days of the same month which resulted in less productivity of the month. However we are tied by the contract that we need to complete the work at a determined date. Hence what is our choice that we have to manage this risk? May be one of the choice is increase the number of work force at the particular month. As now we have the solution to this risk, then the next step is to documented it in our risk management plan. When the event happened we already know what is the consequence and how to address it.

The easiest way out to address any risk in construction is we can always outsource this various trade with certain contract sum to others. In doing this we have the option to outsource the whole trade or only the works. This strategy will help us in a way, should there be any of the risk listed above happened, we already passed this unpredictable situation to others.Thus we can maintain our profit. However a proper agreement have to be prepared and terms and conditions must be clearly stated. One disadvantage of this type of risk management is we are putting our  reputation at a risk if the appointed team do not have a risk management plan.

Friday, August 16, 2013


Stage 1.
1.       Before proceed with any works, survey and setting out shall be conducted to 
       provide the guide on levels and alignment for the construction of the Reinforce 
       concrete Retaining Walls.
2.       Survey and setting out shall be done in the present of Resident Engineer or his 
3.       Request for inspection shall be submitted prior to start the works.

Stage 2.: Earthworks (Excavation)
1.       Earthworks can only commence after the setting out was done and accepted by 
       Resident Engineer.
2.       The sequence of the Earthworks is as the following Diagram 1.

Diagram 1.

3.       The excavation at Sequence 1 will be done until it reaches the proposed platform level 
       where it will provide wider temporary diversion during the construction of the Retaining
       wall structure.
4.       The excavation work at sequence 2 will only commence after the completion of sequence 1.
5.       The sequence 2 will provide access for existing traffic during the excavation work 
       activities at sequence 1.
6.       The Layout after completion of earthworks activities for both sequences will be as the 
       following Diagram 2.

 Diagram 2

Stage 3: Construction of RC Retaining Wall Structure.

Level  1: Piling Works
1.       Piling works will commence after the completion of first half of the sequence 2 
2.       The sequence of the piling works will be done starting form the end Chainage 
       of the Retaining wall progressing to the front Chainage.
3.       The excess of drive R.C pile will be cut as soon as the Piling works reaches 
       practical numbers of piling points to enable the pile cut off activities.

Level 2 : construction of the R.C Retaining wall Base.
1.       The construction of the base will commence as soon as after the preparation of the
       pile head reaches the practical length of the standard steel bar supply length or 
       available safe working area. (eg. Standard steel bar supply length / pcs = 12m )
2.       All of the installed reinforcement must be free from rust, properly tied and being 
      installed according to construction drawings and specifications.

Level 3: Concreting works.
1.       Concreting works will only commence after the installed reinforcement being 
       inspected and accepted and approved for next sequence of works by Resident Engineer 
      or his or her representative.
2.       The sequence of concreting activities will also start from the end chainage of the R.C 
      Retaining Wall base.
3.       Concreting works will commence as soon as the installed reinforcement for the base 
      reaches the possible delivery concrete volume to site per day and practical output of
      the concreting works.
4.       Prior to concreting activities, all installed formworks for the base shall be properly secure 
      to avoid formwork failure.
5.       During concreting activities, test cube and numbers of the cube to be prepared shall be 
      as per directed by Resident engineer or his or her representative.
6.       There shall be no concreting activities during raining day.
7.       The flow of the installation of the reinforcements and concreting activities shall be as 
       per diagram 3.

Diagram 3

Level 4: Construction or R.C Wall.
1.       The construction of the R.C concrete wall shall proceed as soon as the Concreted base 
       is ready to accept the next sequence of the works.
2.       Construction of the wall shall start for both side of the retaining wall concurrently. 
      However some section of the wall might need to be left open to suite the site condition and 
      the movement of machineries.
3.       R.C wall construction activities shall start from end chainage of the retaining wall.
4.       The height of each wall that is ready for concreting shall not exceed 2.4 meter high. This is 
       to avoid the formwork failure.
5.       Prior to fully erect the formwork, wall reinforcement must be inspecting by Resident engineer 
       or his representative for acceptance and approval for next sequence of work.
6.       Prior to concreting activities formwork shall be properly secured to avoid formwork failure 
      during concreting activities.
7.      There shall be no concreting activities conducted during raining day.

8.       Flow of the R.C Wall Construction is as shown in the following Diagram 4.

Diagram 4

Stage 4: Backfilling to completed Retaining Wall.
1.       Backfilling activities will commence as soon as the fully completed section of the 
      retaining wall is ready to received backfill material and also practically safe for the 
      other on-going construction activities for remaining Retaining wall structure.
2.       Each layer of backfill shall be not more than 500mm thick and shall be properly 
      compacted before laying of subsequence layer of backfill. This process is repeated 
      until the whole height of the retaining wall if filled.
3.       Backfill activities will commence from the end chainage of the retaining wall towards
     the CH 6 + 200.

Stage 5: Miscellaneous works.
1.       Miscellaneous works will commence upon completion of the whole retaining wall 
      structure inclusive of backfilling works.
2.       The miscellaneous works are the flexible pavement, drains and  road furniture.

Overall sequence of the stages: