During the course of planning a project, we think about many different ways to build the work. Some people simply follow what the estimator said and others think outside the box for innovative and creative ideas that can save money and achieve the same goal more efficiently and in less time in order to beat the budget and bring in some extra profit. The following is an example of this thinking process.
There are two basic construction methods. We will explore two methods as it applies to the construction of Direct Fixation Track.
- Method 1 is "Top Down"
- Method 2 is "Bottom Up"
Direct Fixation Track is a popular way of fixing rail to a concrete pedestal (plinth), leaving the rail fully exposed and isolated for stray current protection. The old way (bottom up) , and in some cases the still used way; grout pads are poured first, the holes are drilled through the pad and into the invert. Anchor bolts are grouted in place and fasteners attached to the concrete. Rail is set and final alignment and elevation are set with shims. This method is time consuming, not very friendly to stray current and requires the rail to be jacked up very high to change a fastener. The preferred way (top down), sets the rail to exact alignment, gauge and elevation prior to concrete being placed. Fasteners are then attached to the rail with female inserts under the fasteners. Concrete is now placed and the rail is set and ready for trains. This method guarantees stray current protection and exact alignment, both vertical and horizontal. In a tunnel environment, care must be taken to allow for the additional height of the track structure.
Sometimes it is hard to accept that there may be a problem. Sometimes all it takes is an outsider looking in to identify a more efficient and cost effective way to do activities. Everybody can play sidewalk superintendent and hind sight is always 20-20. There is nothing wrong with getting another opinion to evaluate. If a potential problem is identified early, it can save millions. It happens to the best of us, where everything is going along just fine and all of a sudden the crew runs out of inserts and they can't pour concrete and now you are dreaming up busy work for the crew because your convinced that if you lay them off, you'll never get them back. Now your cost is looking bad and you're yelling at the Foreman for not telling you that you were low on bolts. Now you get the inserts flown in and pay an outrageous price for that. You finally get back to pouring concrete, but for some reason you're not getting the same production as when you stopped. This is what is called an interim learning curve. It does happen.
Let The Track Guy share his experience with you!
John Zuspan, President
Track Guy Consultants
934 Royal Court
Canonsburg, PA 15317
Mobile: 973 222-1300
Call The Track Guy today and Let's Talk Track!