By: Marc Stocum, Highway Superintendent, Lindley, NY, and Tony Guizzotti of Unique Paving Materials Corp., Cleveland, Ohio
In May 2012, discussion was initiated to eliminate the daily repair and re-repair for a heavily used bridge near Lindley, NY. The expansion of the shale gas projects in the area had increased heavy truck traffic over the bridge. The flexible wood base supporting the surface is believed partially responsible for the frequent repairs. The increased traffic loading was not anticipated in the original bridge design. The bridge surface is HMA with daily repair. Material shoving and rutting frequently resulted in complaints and constant re-repair. The downward slope approaching the bridge creates severe loading and decelerating forces transferred through the HMA surface to the supporting wood timbers.
According to the Superintendent, repair crews were at the bridge on a daily basis in the summer months. The primary repair material was a locally available conventional cold mix. Something had to change—too much time, effort, and money was being wasted on repair efforts that were habitually failing. Forced repair and re-repair, tying up maintenance crews, limited resources availability in the town, and an unsafe condition for repair crews and traffic….these issues needed to be addressed by Lindley officials.
To identify a permanent pavement repair solution, three repair options were demonstrated. The options were designed to identify the optimum balance between surface durability and supporting timber flexibility.
The pavement repair options included:
- Full depth UPM® Permanent Repair Material, 4-5 inches
- Full depth CPM® concrete, 4-5 inches
- Combination: Concrete on wood timbers topped with UPM (2.5” each)
The pavement repair materials were installed May 9, 2012. Pictures taken before, and throughout the demonstrations, documented materials performance – providing a reference for material comparison over time.
The following write-up details the formal monitoring portion of the trial. The preferred repair material and technique selected for future applications was the full depth UPM Permanent Repair Material.
The underlying wooden bridge deck is subject to continuous loads and movement, causing constant repair problems to the road surface.
Crews prepared three identical holes for installing and evaluating the options to solve these ongoing problems.
Products and methodology tested and evaluated
- UPM Permanent Pavement Repair Material—the original asphalt permanent repair material, since 1959, designed to fix potholes permanently “Once and Done.” Unlike most cold patch products which have no inherent engineered design chemistry, UPM is formulated to the specific characteristics of the aggregate being used and stringently manufactured by UNIQUE Paving Materials Corp. to bond and adhere both to itself and to the road cavity it is correcting.
- CPM—DOT, a product of UNIQUE, is a concrete patching material specifically designed to develop a permanent bond with existing concrete. It is fast-setting, has high early strength, resists chlorides, and provides superior freeze-thaw resistance.
- CPM—DOT base with UPM overlay.
May 9, 2012: Installation of All Materials
Holes were square-cut and swept as is per manufacturer recommendations for best adhesion and cohesion of repairs.
UPM Permanent Repair Material being installed into holes, raked into place.
UPM being compacted using a vibratory plate tamper. Compaction is critical in activating the cohesion/adhesion chemistry of UPM and in eliminating air voids which contribute to premature road failure.
CPM-concrete installed into repair demonstration 2 (full depth concrete).
Performance Observations: May 20, 2012
- UPM full depth, 100% success, no pushing, shoving, spalling, rutting or loss of material.
- Full Depth DOT mix initially cracked on small section onto the steel bridge expansion; the rest of the area held out 100% no movement of test material, no shoving and no loss of material.
- CPM-concrete base with UPM overlay performed equal to the full depth UPM. The repair experienced no movement or loss of material, shoving prior to test area but not the test. The test section kept its shape and remained intact. The condition of the concrete below the UPM was not inspected. It was assumed acceptable due to the quality of the UPM surface layer.
The repair areas are highlighted in the pictures below to identify repairs due to the similar appearance of UPM and the surrounding HMA.
Mr. Stocum was very impressed with all three test and demos and the Town of Lindley is now a convinced and satisfied UPM customer. Mr. Stocum now strongly believes in the performance and value of UPM Permanent Pavement Repair material, as well as the expertise and quality focus of UNIQUE to solve challenging road repair and maintenance problems.
The original installed UPM® remains in place from the initial installation May 9, 2012. The daily repair and re-repair process for the Lindley maintenance crew has been eliminated by a “Once and Done” solution. The savings in time and money, along with creating a safer working environment for road crews, is a welcomed change in road maintenance strategy.
The demonstration successfully concluded July 9, 2012, after the 60-day formal monitoring period. Throughout the demonstration, frequent inspections including pictures documented repair material performance.
Additional Evaluation and Postscript:
On September 19, 2012, Marc Stocum and Tony Guizzotti met at the site to further inspect and evaluate the ongoing performance of the repairs. Mr. Stocum stated the pavement repair material is exceeding his expectations and that he is very pleased with the results of the three test products.
The CPM concrete test repair met the time test period, but was later removed, due to cracking caused by the flexible wood substrate and the rigidity of the concrete. Interestingly, due to Mr. Stocum’s desire to deplete some previous inventory on hand, he used a competitor’s product -“Q” – which subsequently failed and had to be replaced with UPM. UPM provides the highest degree of both road flexibility and surface endurance, and it continues to perform without failure.
The full depth UPM is functioning well, with no signs of spalling or rutting. Furthermore, the full-depth UPM installation is the lowest cost of the methods evaluated including equipment costs saved as well as costs associated with time and labor avoided. This was the solution preferred and selected.
Mr. Stocum said he now truly believes UPM is a permanent solution to a problem of revisiting and constantly repairing the same potholes and repairs over and over and over again. UNIQUE promotes UPM as “Once and Done™” and, Mr. Stocum said, “That is definitely true based on our experience here.”
Mr. Stocum feels very strongly and favorably about the performance of UPM and UNIQUE’s ability to show value by using a permanent cold patch product engineered for this purpose versus the standard temporary cold patch products that had been used previously. Also, he highly recommends UNIQUE and UPM, both to his fellow highway superintendents in the Steuben County Highway Superintendent Association, as well as others with road maintenance and repair headaches that most other products and companies just cannot handle.
UNIQUE is about more than just products—UNIQUE prides itself on Total Permanent Engineered Solutions to road maintenance and repair headaches. As the most valuable and experienced partner, since 1959, for road maintenance agencies, UNIQUE has the resources and expertise for solving both routine as well as unusual roadway repair problems.
“Once and Done” means not spending dollars continually on repairs, re-repairs, and failed repairs. It enables today’s cash-strapped agencies to maximize the value of every dollar spent. Give UNIQUE a call today and let’s get started on finding the most cost- and performance-effective solutions for all your road maintenance problems.
Update Nov 2012: After six months of continuous service with no repair issues related to the UPM permanent repair material, the bridge was milled and resurfaced. Milling removed approximately two inches of surface material. The aged HMA and UPM repairs were indistinguishable. Unlike lesser materials which would have needed to be removed prior to overlaying due to risk of bleed-through and further damage, the milling left UPM in each of the three repairs. The resurfacing overlay was installed over UPM with no problems. Overall, the performance of UPM permanent repair material was considered a total success. The option to permanently repair deteriorated HMA until overlay options became available provided a cost-effective solution to extend the maintenance budget as well as the useful life of this bridge.
Mr. Marc Stocum, Highway Superintendent, Lindley, NY 607-523-7294
Mr. Tony Guizzotti, Unique Paving Materials Corp., Cleveland, OH 585-944-6660
Content provided by Unique Paving Materials Crop.