Associações entre manifestações patológicas e controle tecnológico e execução do concreto: estudo de caso em edifícios de múltiplos pavimentos

Abstract

This study investigates the association between concrete technological parameters, concreting execution conditions, and the occurrence of pathological manifestations in the structural elements of a multi-story building located in Campo Grande, Brazil. Based on records from the project's Quality Management System (QMS), 145 ready-mixed concrete truckloads placed between the 7th and 14th floors were traced, relating slump test results, total transport time, and concrete compressive strength to pathological manifestations identified after formwork removal. A total of 92 pathological manifestations were associated with 54 concrete truckloads (37.2%). Statistical analyses (Mann-Whitney, chi-square, and Fisher's exact test) showed that concrete consistency at delivery exhibited the strongest association with pathological manifestations: truckloads received outside the specified slump range showed a 71.8% incidence, compared with 24.5% for those within the specified range (OR = 7.8; p < 0.001). In contrast, concrete compressive strength and total transport time showed no statistically significant association. Field inspections identified recurrent execution-related deficiencies, particularly during concrete placement and consolidation, indicating that technological control alone is insufficient to ensure the final quality of reinforced concrete structural elements.