Contribution of MnROAD Research to Improvements in Concrete Pavement Technology from 1994–2019

Abstract

By the late 1980s several states, including Minnesota, began to wonder if American Association of State Highway Official (AASHO) based asphalt and concrete pavement designs were still valid, given the significant changes in traffic loads, materials and construction practices over time. This interest in validating current designs, as well as seeking improved and more efficient designs and materials, led to the creation of the Minnesota Road Research facility, known as MnROAD. Construction of the first phase of test sections at MnROAD took place from 1991 to 1994, and it was open to traffic loading commencing on July 15, 1994. Since 1994, three phases of pavement research have been, and continue to be, conducted at MnROAD. In its first 25 years of operation, an overwhelming amount of pavement research and development has been accomplished at MnROAD. The focus of this paper is to describe many of the more unique and significant findings that have improved concrete pavement technology not only in Minnesota, but throughout the U.S. and other parts of the world. The contributions are categorized into the following areas: design, materials, construction, rehabilitation, pavement monitoring and evaluation, and full-scale testing. In each of the areas, the significant contributions are described and relevant references are cited. The positive contributions of MnROAD toward concrete pavement knowledge and technology have been recognized, and as a result, the MnROAD facility will continue to operate successfully into the future under the National Road Research Alliance (NRRA).

Characteristics and analysis of static strain response on typical asphalt pavement using fiber Bragg grating sensing technology

“…In the late 1950s, experimental roads of American Association of State Highway (AASHTO) were paved, which still had an influence on the development of pavement technology worldwide (Metcalf, 2016;Milad et al, 2022). The MnROAD project in Minnesota, United States, provided a foundational platform for analyzing and comparing the service performance of various pavement structures (Burnham et al, 2020). In the middle 1990s, the WesTrack experimental roads of Western Beltway in America was used to study the design specifications for hot-mix asphalt mixture based on the serviceability, which strongly supported the innovative research of the Superpave design method (Wen, 2003).…”

Contribuição à análise da conformidade de elementos construtivos de pavimentos de concreto e suas implicações estruturais com auxílio de ultrassonografia.

“…Segundo a FHWA (2019) a definição do tipo de selante a ser adotado dependerá do tipo de junta e de seu movimento esperado, das características climáticas locais, do tipo e volume de tráfego, da compatibilidade química com material de substrato (por exemplo, sensibilidade de alguns selantes de silicone ao agregado de calcário), necessidade de cura rápida do selante, necessidade de resistência a derramamentos de combustível ou jatos, custos de material e instalação e vida útil esperada.Contudo, ainda segundo a FHWA (2019), não há um consenso a respeito da relação custobenefício da vedação das juntas em pavimentos de concreto. Estudos conduzidos, a partir da década de 1970, pelo Departamento de Transportes de Wisconsin em seções experimentais não vedadas (sem selante) representando uma variedade de projetos e condições de tráfego avaliadas ao longo de 15 anos, mostraram que pavimentos não selados apresentavam desempenhos comparáveis a pavimentos selados, o que levou a partir da década de 1990 o Departamento de Transportes de Wisconsin a adotar uma política de não vedação das juntas de pavimentos de concreto novos e de pavimentos emBurnham (2012), por outro lado, ao estudar o impacto da selagem das juntas no desempenho de whitetoppings delgados observou que a selagem das juntas apresenta benefícios significativos no desempenho do revestimento aderido ao revestimento asfáltico. Segundo o autor, isso provavelmente ocorre devido a infiltração reduzida de água mitigando a degradação da ligação (aderência) entre o asfalto e o concreto Balbo (2009).…”