Utilibond Permanent Pavement Bonding Compound
While there are a variety of coring tools available, the key element in the pavement reinstatement process is the bonding compound used to restore the repaired roadway.
To be effective it must be able to bond the core to the remaining intact slab of pavement in a manner that allows the road to again perform as a system and to share the effect of traffic loading. It must also generate sufficient bond strength to quickly meet relevant AASHTO standards and allow the road to be opened to traffic as soon as possible.
Utilibond™ is the only specially formulated and engineered bonding compound designed to be used for permanently reinstating pavement cores in asphalt and concrete roads, sidewalks and other paved surfaces.
A ready-to-use (just add water), fast-setting, high-strength waterproof bonding agent, Utilibond™ is non-toxic and comes in two colors (Aged Asphalt and Natural Concrete).Utilibond™ was developed and field-proven over 10 years by the Consumers Gas Company (now Enbridge Gas Distribution), one of North America's oldest and largest local gas distribution companies with over 1.5 million customers, as part of its innovative rotary coring and keyhole pavement reinstatement program.
Testing by Golder Associates (1992-2002)
In June 1992, Enbridge retained Golder Associates, a highly respected international engineering firm, that provides science and engineering consulting services in support of environmental, industrial, natural resources, health and civil engineering projects.
Golder was asked to provide consulting and testing services in the development of a new pavement reinstatement system following rotary cutting of the pavement for gas service repairs using keyhole repair technology. That work encompassed a series offield trials and laboratory tests on a broad cross section of potential bonding materials undertaken over the period 1992 to 1996.
Ten years later, in October 2002, a follow-up study was commissioned to confirm previous results and to update performance data on the current version of Utilibond™, which is the third generation of the proprietary bonding compound originally selected for the process. The Golder study is the only ten-year longitudinal study to evaluate the effectiveness of a road reinstatement process by monitoring the degree of coupling between the undisturbed road structure and the newly restored utility cut.
According to Golder Associates:
"Effective coupling is achieved where the road will share the effect of traffic loading, as postulated in conventional road design theories. The lab trials and previous demonstrations on the rotary cutting method have shown that the pavement coupon has been bonded into the slab in such a manner that the loads of traffic are effectively transmitted to the remaining intact slab.
In addition, the investigation of former trials over a number of years indicates that the repair technique continues to perform well. Based on this successful performance, the City of Toronto has approved the Utilicor™ pavement restoration technique as a permanent replacement. Based on trials carried out at our testing laboratory in Whitby and our in-field performance observations, we are satisfied that the equipment, procedures and materials [including Utilibond™] developed and used by Enbridge Gas Distribution over the last 10 years will ensure satisfactory long term performance of pavement reinstatement.
Download the complete Golder Report.
More recently, in July 2003, the performance of Utilibond™ was again tested and compared with two other bonding compounds currently being experimented with in California and Pennsylvania. These tests were undertaken by Professor David A. Lange, Ph.D., P.E., FACI of the Department of Civil Engineering at the University of Illinois at Urbana-Champaign.
The objective of Rotary Coring and Reinstatement technology, and that of its competitors, is to cost-effectively and permanently restore a pavement to its pre-excavated condition and allow it to accept normal traffic loads as soon as possible after the repair. The tests focused both on absolute bonding strength as well as on the time taken for the various bonding compounds to achieve sufficient strength to meet or exceed AASHTO standards.(The AASHTO Guide for Design of Pavement Structures is used for concrete pavement design in the United States and other countries).
In his conclusions, Dr. Lange reported that "the Utilibond™ material excelled consistently as a rapid set material, and achieved the highest punch out loads at all test times," and that while all three bonding materials proved capable of achieving high safety factors in the core punch out test over time, only the Utilibond™ material demonstrated satisfactory performance in the 30 minute tests.
Given the proposed application, it was Dr. Lange's opinion that this substantial time differential represented a significant difference in performance and that "rapid set time and workability are meaningful attributes in the field application, and effectively differentiate the performance of bonding materials for reinstatement of cores".
Download the complete Lange Report - Testing at University of Illinois