Construction Of Twin Railway Track On Viaduct

Project Scope

1. Linear Project’?

This is a project with a repetitive task feature such that its configuration is in a parallel fashion and serves to transport utility products such as electricity, water, oil, vehicles, gas and even communication among others.

Examples of the various types of Linear Projects include:

     -Construction of oil pipeline

     -Bridge and road construction especially long kilometer highways

1. A section of a new High Speed Railway (HSR) route will cross a large estuary on a twin track viaduct. The total length of the viaducts required to achieve this together with the approach sections on land are as follows:

   Chainage (km):

   Save Time On Research and Writing

   Hire a Pro to Write You a 100% Plagiarism-Free Paper.

   Get My Paper

   0-4: Tracks on grade with access roads available beside tracks
   4-7: Tracks on viaduct over land (access roads at ground level)
   7-10: Tracks built on viaduct over the estuary
   10-14: As for the 4-7km section above
   14-20: As for the 0-4km section above
   Methodology of the installation of the twin track work

1. Planning

Based on the site requirements and the project objectives, the planning team will establish the capacity so that amount of work to be handled per day can be known. The general profile of the project both horizontal and vertical shall be reviewed with the aim to comprehend the various unique requirements along the stretch.

1. Production of rail track materials

Production of essential materials such as concrete sleepers and concrete shall be done as soon as the planning team starts their planning work. At every point of each phase, there will be a production unit for the said materials. This will also provide buffers for materials such as rail. Track laying will be split into five phases. It should be noted that each phase has unique laying attributes hence different equipments and machines will be utilized. For example, when laying the track over the estuary, a rail lifting crane will be used while the on-ground laying, the automated track laying machine will come in handy.

Table 1: Laying Phases

PHASE	FEATURES
First (0-4km)	Near access roads
Second(4-7km)	Overland stretch (access roads underground)
Third(7-10km)	Over the estuary
Fourth(10-14km)	Overland
Fifth (14-20km)	Near access roads

Prior to laying work, the access roads shall remain closed both as a safety and quality control strategy. Meanwhile, the laying machine is brought to the site as planning team completes its work ready for the work from 0 to 20km. The ground will also be checked for stability. The team will rely on the geotechnical engineer’s data obtained during the feasibility study. In sections where stability was noted as inadequate, the civil engineering team (prior to laying work, they must have developed plan to overcome this challenge) will work on ground stabilization accordingly.

1. Check drainage

Additionally, the local drainage at every section will be ascertained prior to laying and appropriate systems to curb poor drainage shall be made available.

1. Track laying

• Ballast pouring and Sleeper placement

Beginning from phase 1 at 0km, just enough ballast is poured by the trucks and accurately leveled by compacting machine. Quality of ballast spread and leveling must be checked by the quality team. Meanwhile, the produced concrete sleepers are brought to the site via trucks. They are then correctly spaced according to the technical plans. The inter-sleeper distance is to be checked by using efficient sleeper placement machine. Based on the international standards, the placement rate is normally between 24 and 26 sleepers per 60 feet. Hence assuming the team uses average rate of 25 sleepers per 60 feet. The total number of sleepers is therefore given by the formula: Sleeper rate x length of stretch

• Rails on site

Project Schedule in TCD Format

The rails are brought to the site via wagons, each of length 120m. Normally they would be brought from the shipment depot. Meanwhile, the manufacturer of the rails will have to be ahead of the laying team in terms of production rate so as to avoid delays caused by material being unavailable. To facilitate transportation, the rails will be made slightly shorter than the standard sizes and their ends, after laying, will be joined by welding.

• Actual laying work

Laying will be done using an efficient track laying machine such that the rails are automatically dropped on the prepared track ground where sleepers are already placed. Once placed, they are then fixed to the sleepers as the machine moves over the laid rail track. To prevent unnecessary buckling due to thermal stresses, the rails once laid are pre-stressed. Since this is a twin –track rail system, there will be two machines working simultaneously.

• Top ballast Pouring

They are then showered with ballast. This is done using a train wagon such that it travels slowly as it spreads the top ballast. This is to ensure sleepers are held accurately on rail.

• Tamping

It will be followed by a compacting machine. This machine lifts the sleeper and rail and pushes some ballast underneath to further stabilize the track, ensuring the design and geometric requirements are realized.

• Finishing

Finally, the track will be smoothed using an automated track finishing machine. 

Construction plan and equipment	Designation
Lifting crane	For rail lifting over estuary and over land
Mixers and pumps	For concrete preparation
Rail track laying machine	Laying  the track automatically
Bridge launching equipment	Carrying the deck and placing over bridge
Trucks	Transporting the track material to site
Sleeper placement machine	Placing sleeper automatically
Compacting machine	Firming and leveling the ballast once poured
Tamping machine	Providing sufficient compaction and stabilization
Hydraulic jack	To facilitate Light lifting of materials over heights
Bulldozer and grader	To clear any vegetation including roots and stumps that is still in the vicinity

b2. Prepare a construction schedule for the track installation contract on the viaduct using Time-Chainage Diagram (TCD) format in XL or AutoCAD showing all activities that need to undertaken for the construction of the twin railway track including site establishment, and equipment set up.

Construction Schedule (Time chainage)

It is assumed the activities occur in a uniform manner for all phases.

Check the attached excel file for the diagram .

The construction duration can be estimated as follows:

Laying rate per day= 250m (inclusive of material transport, production and holding)

Total laying period= 20 000/250= 80 days equivalent to 2 months, 20 day

b3. Prepare a second TCD, assuming that installation work will start at the 0km and the 20km chainages at the same time. Include all assumptions and calculations for estimating construction durations. What is the difference in total construction time between b2 above and b3?

Construction Schedule (Time chainage)

Check the excel sheet attached. In this case, it is assumed that the meeting point for the concurrent phases occur at the 7km chainage point. In this case, since the two set of activities are running concurrently, the construction time is slashed by half hence: 40 days only required. However, there is a possibility of doubling the labor capacity.  

Construction Processes

b4. A Safe Work Method Statement (SWMS) for the track installation work on the viaduct

Safe Work Method Statement (SWMS)

The following shall be complied with while within and around the construction site:

1. Working at heights

The supervisor shall assess the height prior to working and appropriate gears made available. Standard operating procedures shall be followed to the letter.

1. Falling objects

It is the responsibility of every worker to remain vigilant for any signs of objects falling. Necessary measures shall be instituted to regulate objects movement and position at heights.

1. Crane Use

The operator shall be experienced personnel in crane operations with a history of non-negligence at work. The crane shall be operated as provided in the operator manual. No use of the crane other than the one specified shall be allowed.

1. Personal Protective Equipment

These shall include: hard hats, safety boots, eye face protection, skin protection and hand gloves. These shall be revised as deemed necessary.

1. Housekeeping

All equipments, tools and machineries shall be returned to their proper storage location. Foremen shall ensure the right equipment inventory is issued and returned accordingly. All clutter shall be cleared after a day’s work unless otherwise directed by site supervisor.

1. Flammable materials

All workers shall practice safe handling, storage and use of hazardous and flammable materials.  Regular trainings shall be conducted to keep workers abreast on the same. No smoking shall be allowed within and around the construction site.

1. First Aid

For every 5workers (at whatever level and trade), there shall be one who is a trained first aider and shall be allowed by the safety manager to address the following emergency situation:

-Bleeding

-Burns

-Resuscitation

First aid kits shall be available at every workplace and shall be in the custody of the assigned first aider.

1. Accidents Reporting

Should any safety incident occur, this must be brought to the attention of the foreman or section supervisor. Meanwhile, the information shall be made available to the Site supervisor and quality manager within 24 hours. There will be templates to fill the emergencies.

1. Accident investigation and measures

All accident occurrence shall be investigated by the safety team and report made available to the project manager within 2 days. Appropriate corrective actions shall be undertaken thereafter

Although the authors tend to discredit schedule-driven projects at face value, I tend to agree with the Australian author that schedule-driven projects often instill some sense of professional work discipline at an individual level (Sankaran, 2016). Normally, they aim to navigate the scope of work and minimize inefficiencies caused by mismatch between the objectives and the scope. The temptations to veer off the well defined road map are a major contributor to the unnecessary costs being incurred. In schedule-driven projects, these changes are anticipated hence accommodated in the budget.

However, there are situations when the project can be thrown into limbo. For instance, due to political reasons, a certain project can be cancelled prior to launching. Admittedly, project managers must be very sensitive both internally and externally. One ear must be inside while the other is focused outside so that any threats are identified beforehand and prudent actions are taken (Sankaran, 2016). For example, in projects with high impacts on environment such as installation of on-shore oil pipeline, there will be need for continuous compliance with the regulations otherwise litigations and suits will add unnecessary costs and even lead to project halting and cancellation.

Moreover, as pointed out by Frago (2018), quite a number of inexperienced project professionals often misunderstand the term “Schedule-driven”. This then causes confusion amongst the team as different interpretations are made. In fact this is the major cause of failures for projects under schedule-driven terrain. Therefore, it is often required that experienced professionals occupy the senior management positions such that they can greatly assist with professional steering of the project. Additionally, schedule driven project must be implemented curiously, in other words, there needs to be a striking balance between schedule-driven and resource-driven approaches especially for the complex projects like the one presented above (Frago, 2018).

References

Frago,R. (2018). | Project Controls – planning, scheduling, cost management and forensic analysis (Planning Planet). [online] Available at: https://www.planningplanet.com/blog/schedule-driven-projects (accessed 20/1/18) [Accessed 31 Mar. 2018].

Sankaran, S. (2016). Industrial Megaprojects: Concepts, strategies and practices for success. Project Management Research and Practice, 3, p.5118.