Experimental continuously reinforced concrete pavement parameterization using nondestructive methods

Abstract

ResumoFour continuously reinforced concrete pavement (CRCP) sections were built at the University of São Paulo campus in order to analyze the pavement performance in a tropical environment. The sections short length coupled with particular project aspects made the experimental CRCP cracking be different from the traditional CRCP one. After three years of construction, a series of nondestructive testing were performed -Falling Weight Deflectometer (FWD) loadings -to verify and to parameterize the pavement structural condition based on two main properties: the elasticity modulus of concrete (E) and the modulus of subgrade reaction (k). These properties estimation was obtained through the matching process between real and EverFE simulated basins with the load at the slab center, between two consecutive cracks. The backcalculation results show that the lack of anchorage at the sections end decreases the E and k values and that the longitudinal reinforcement percentage provides additional stiffness to the pavement. Additionally, FWD loadings tangential to the cracks allowed the load transfer efficiency (LTE) estimation determination across cracks. The LTE resulted in values above 90 % for all cracks.Keywords: concrete pavement, consitnuous reinforcement, deflections, backcalculation, load transfer efficiency.Quatro seções experimentais de pavimento de concreto continuamente armado (PCCA) foram construídas no campus da Universidade de São Paulo com a finalidade de analisar o desempenho deste tipo de pavimento em clima tropical. A curta extensão das seções aliada a aspectos específicos de projeto fizeram com que o PCCA experimental apresentasse um padrão de fissuração bastante distinto dos PCCA tradicionais. Passados três anos da construção, realizou-se uma série de testes não destrutivos -aplicações de Falling Weight Deflectometer (FWD) -para verificar e parametrizar a condição estrutural do pavimento com base em dois fatores principais: o módulo de elasticidade do concreto (E) e o módulo de reação do subleito (k). A estimativa das propriedades foi obtida através da equiparação de bacias reais com bacias simuladas pelo programa EverFE para a carga aplicada no meio da placa formada por duas fissuras. Os resultados da retroanálise mostram que a falta de ancoragem no final das placas diminui os valores de E e k e que a porcentagem de armadura proporciona um adicional de rigidez ao pavimento. Adicionalmente, aplicações de carga tangenciais às fissuras possibilitaram a determinação da eficiência de transferência de carga (LTE) entre fissuras. A LTE resultou em valores acima de 90% para todas as fissuras.Palavras-chave: pavimento de concreto, armadura contínua, deflexões, retroanálise, eficiência de transferência de carga. L. S. SALLES a

Non-destructive ultrasonic tomography for concrete pavement evaluation: signal processing and image analysis of crucial parameters

“…The experimental sections are: (I) a parking lot with jointed-plain concrete pavement (JPCP) with slab thickness of 150 and 250 mm, (II) a ultra-thin whitetopping (WTU) with a 100 mm thickness located at a bus stop and (III) a continuously reinforced concrete pavement (CRCP) with a 240 mm thick slab located on an avenue. Constructive data and structural analysis on these three pavements can be found in Balbo and Severi [26], Balbo and Pereira [27] and Salles et al [28], respectively.…”

Short continuously reinforced concrete pavement design recommendations based on non-destructive ultrasonic data and stress simulation.

“…As Section 1 had not yet showed any visible cracks, the FWD took place 5 m from each transverse edge and 10 m apart for subsequent locations. The complete backcalculation process can be found in Salles and Balbo (2016).…”