Multi screw type elements for weak soil reinforcement

The object of research is weak soils reinforced with fiber-reinforced plastic pipes with helical screws of increasing diameters from bottom to top, installed in weak soils at defined spacing. The study aims to develop and validate a new predictive settlement calculation model for weak soils reinforced with fiber-reinforced plastic pipes with helical screws of increasing diameters from bottom to top, installed in weak soils at defined spacing. Method. Method is based on a comparative review of closest researches. The reinforced mass is treated as a composite structure in which the vertical elements and surrounding soil undergo joint and simultaneous deformation. An analytical settlement calculation model was formulated based on a newly introduced reinforcement factor, which accounts for the geometry and structural characteristics of the reinforcing elements. Results. To validate the model, five full-scale axial load tests were conducted on soils reinforced with elements of different configurations. At pressure 300 kPa settlement reductions of 63% (samples with two screws) and 72% (three screws) were achieved. Comparative analysis of the calculated settlements and experimental results demonstrated the accuracy and applicability of the proposed method.