Some new things to see at ConExpo 2011

Written by Marco Cecala

Created on Wednesday, 09 March 2011 20:26

Some new things to see at ConExpo 2011
It is going to be a great year for new products at ConExpo. I have had the chance to review a couple of them. Certainly worth a look.

Topcon's New Road Profiling Solution RTP-300
A recent study of DOT's across the nation show that over 70% of their contracted work is in replacing asphalt pavement on existing roads. The issue of maintenance has always been present, but over the past four years it has been reduced to critical items only. With more roadways waiting longer for a refresh, more are getting critical. This represents a great opportunity for the contractor. "Mill and Replace" work is straight forward. To be profitable, the contractor has always needed to blend science and art. Let's review what is required.

In a mill and replace job, the contractor will scarify the top surface of the asphalt then pave over it to provide a renewed surface. There are two critical items that contractors closely watch, Coverage and Ride Quality.

• Coverage. In the specifications for a mill and replace job, there is a minimum amount of cover that is required for the new overlay. Providing you don't exceed the lift thickness, the agency is not usually concerned about how much material is placed. The minimums need to be met. The contractor will do their best to make sure that the pavement thickness is enough to do the job, but not waste material.

• Ride Quality. Without drilling down into the details, all these jobs are out to accomplish two major goals. Make the pavement new, and make it smooth. Specifications will call out what Ride Quality Index (RQI) is required for the project. Often times there is a substantial bonus or deduction to the contract directly relating to the RQI.

The contractor is expected to do the following:

• Mill a specified minimum amount of the existing asphalt, deeper as required meeting the proposed profile of the "new" road.

• Warp the cross slopes correctly to catch existing curbs, driveways and drainage structures. This is in addition to the new profile that will serve to compound the difficulty of the typical sections.

• Pave the new road to at least the required minimum thickness, but not so much that material consumption erodes profits.

• Subject the completed project to precision measurement that will dictate the addition or deduction of payment in regard to the Ride Quality.

Topcon's RTP-300 has the ability to provide a comprehensive solution. Here is how it works.

• Attaching to any truck with a receiver hitch, the existing road surface is accurately measured at speeds up to 65 miles per hour.

• The topo map is brought into Topcon's Site Master Software or any CAD program to work out the design. The desired parameters are entered; these can include limits for vertical curves, cross slopes and milling depths.

• The new road model is output to the guided machines. Machine guidance can be used for the milling and paving portions of the job. The contractor has flexibility in how they wish to proceed.

With all these advantages at their disposal, the contractor will not only want to go after mill and replace work. They can now feel confident it can be done profitably on a consistent basis.

New Trimble Partnership Will Increase the Use of BIM
I briefly wrote about the new joint venture between Trimble (www.trimble.com) and Tekla (www.tekla.com). BIM, (Building Information Model) is the acronym for the electronic pre-assembly of all required components for vertical construction. The model is checked for potential "collisions" with other work so problems can be worked out before they occur. One big advantage of the technology is for a buildings MEP systems, (Mechanical, Electrical, and Plumbing).These complex systems are competing for space in a buildings utility chases. With BIM used during design and planning, the contractor can go as far as pre-bending and cheaper offsite fabrication of major runs and assemblies. This is a great boost to profits and efficiency.

Here is an explanation of the stand alone products that make up the new partnership.

• Trimble Layout Solutions. Initially, Trimble released the LM 80 as their solution to one or two man layout. The software is easy to use and can be operated using a two person total station, or a robotic total station for one person use. The LM80 software is easy to use and is a natural for the layout of anything required in 3 dimensions for a job. I initially used it and was excited about its accuracy for placing forms, bolts, anchors and steel for concrete work. I knew after spending a few hours with the software and getting used to it, a contractor could really increase productivity and all but eliminate errors. With improvements and additions to the software, the work can be completed in the office and transferred to the field for use. The potential exists to add additional placements in the field, something that always seems to happen.

• Tekla BIM Software. The LM 80 does a good job, even with the robust software provided, there was so much more that could be done. Enter Tekla Structures. With this software integrating into the Trimble layout solution the package becomes more powerful. For this article I will just deal with the concrete contractor. On the front side, the contractor can use the software to bid the job. Rebar weight and concrete volumes are easily calculated. When it is time to move to the field, the files are seamlessly transferred to the Trimble equipment and layout begins. From footings to walls, all the required information is available for layout, verification and retrieval. The strength of viewing a 3D model of the structural components cannot be stressed enough. The user has the ability to look at how things are going to be upon completion. A huge time saver for unique designs that seem to take more time to figure out than layout.

The world of BIM (Building Information Model) and CIM (civil Integrated Management) is still getting started. The technology has already proven itself as a way to improve efficiency and profitability. The software platforms are getting easier to transfer between each other and user interfaces are more intuitive. Start looking and get ready to see the results. ConExpo is a great place to accomplish this.

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