Multi screw type elements for weak soil reinforcement

Research aims to develop a method for weak soils reinforcement by using multi helical vertical elements. Model of settlements forecast is required. Article represents the results of investigation held during several years. Structure of vertical reinforcement is designed by using fiber reinforced pipe and helical screws those have differentiated from bottom to top diameters. Reinforcement elements are located within weak soil with certain step. Reinforced soil is considered as a composite structure where vertical elements and surrounding weak soil have joint and simultaneous settlements. These settlements’ calculation model was developed. Calculation equation is based on newly proposed reinforcement factor. Reinforcement factor is appointed considering existing researches and depends on vertical reinforcing element’s structure. Developed model needs to be confirmed by site full scale axial loading tests. Five sets of site load tests were performed before and after reinforcement of a weak soil. Test samples varied by structure of reinforcing elements. A comparative analysis of the calculated vertical deflections and the results of site loads test proofed possibility of settlements calculation method use.

***ARTICLE IN PRESS***