The Influence of Concrete Grinding Residue on Soil Physical Properties and Plant Growth

Abstract

Diamond grinding is a concrete pavement maintenance technique, and concrete grinding residue (CGR) is the byproduct. Concrete grinding residue deposited along roadsides affects soil chemical properties, but impacts of CGR on soil physical properties and plant growth are rarely studied. In this study, a controlled field experiment was performed to determine the influence of CGR on selected soil physical properties (i.e., bulk density [ρb], saturated hydraulic conductivity [Ks], and water infiltrability [It]) and on plant biomass and plant coverage under four application rates (0, 2.24, 4.48, and 8.96 kg m−2). Field measurements were performed before the CGR applications, and 1, 7, and 12 mo after the CGR applications. No significant CGR effects on soil physical properties were detected. The ρb was relatively stable for all of the treatments, whereas some nonsignificant variations (e.g., 10–30% of mean Ks values and mean It values among four CGR rates) were found. Plant biomass with a CGR rate of 2.24 kg m−2 tended to be 10 to 40% larger than biomass in the control treatment, whereas plant biomass with a CGR rate of 8.96 kg m−2 tended to be ∼10% smaller than the control treatment. Concrete grinding residue had no significant effects on plant coverage, richness, Simpson's diversity, and evenness. Thus, CGR applications up to 8.96 kg m−2 did not significantly affect soil physical properties and plant growth in this controlled field study. This study can serve as a reference for results obtained from roadsides in Minnesota and Iowa that receive CGR applications.Core Ideas Concrete grinding residue (CGR) was evaluated in a controlled field study. CGR applications <8.96 kg m−2 did not significantly affect soil physical properties. CGR applications did not significantly affect plant biomass and community properties. The results provided a reference for diamond grinding in Minnesota and Iowa.