There is something that bothers me  about some magazine articles. I see the title and expect to learn about the subject. After reading I find myself wanting more, there was nothing for me to sink my teeth into, I always try to give you some real information. My last two submissions dealt with getting data to the field, then back into the office. We will now implement that learning into real world situations.  Names and locations will be changed to avoid nasty letters, but the situations are real. The take home message here is without good data generation and management, the contractor stood to lose a lot of money.

Will the real topo please stand up?  This road job was bid from quantities provided by the engineer. The contractor won the bid and took their own topo. They could not get the numbers to match those of the engineer, that is not a problem, but the numbers were way off. We started to look at the job and found the following areas that helped to find the missing dirt.

When the data was transferred into the office, the job started and any hopes of visiting the existing conditions again were gone. The first thing we noticed was that the contractor’s topo did not pick up the ditch. We added the ditch bottom because the top of the slopes matched well.

The job was the repaving of a highway with some additional clean up for the grading areas outside the shoulders. On the plan sheets the contours for the existing conditions showed the asphalt in place. The paving had been removed by others before the job began. The cross sections showed the paving gone, that was the other big difference in the numbers. Using the elevations to the removed paving sections, we now got a cut/fill quantity in line with the original estimate. The problem this caused was the fact that the job was short on dirt, the contractor was instructed to bring in dirt from other areas.

We still needed to try to get to the original dirt number from the engineer, that way we could track the differences from the plans and help the contractor to get compensated fairly. We now have retentions deeper than planned, the contractor took another topo to the subgrade. With this new quantity, and the fact we could track the dirt moved with the weekly topo’s, the contractor provided a convincing presentation.

When in doubt, shoot a point, make a topo, take a picture. Without all the data collected, the contractor would not have received the money they deserved.

Just match the existing pavement.  How many times have we heard that? The process of performing lane additions to a roadway usually calls for the curb and gutter to be built first. The curb elevations are built to plan, then the road is saw cut and paved against the existing.  The road needs to maintain a 2% crown to the gutter, if the new curb is not at the correct elevations the slope will not be right.
It is easy for the contractor to take shots along the proposed saw cut line. After they send the points to the office, the road plan is verified so the curb can be set to the correct height.

We can build the job 100 times on the computer before you waste any diesel fuel. In this case the ripple effect of the saw cut topo shots would require the re-design of the intersection. When we got the paving grades from the contractor, we worked on the intersection to get it correct and submitted that to the engineer for review. The changes were incorporated into the design and revised plans were distributed.
There are numerous ways that data can make your work more profitable and efficient. In these two cases the contractor might have prevailed without using data to their advantage. There would have been more dirt imported and equipment brought in, curb removed and replaced, letters and meetings. It was nice just to do the job quickly and efficiently, after all, isn’t that what it’s all about?

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