ANALYSIS OF THE PERFORMANCE OF TIE-RODS ANCHORED IN COHESIVE SOILS, THROUGH THE NUMBER OF INJECTION STAGES

Abstract

One of the major difficulties related to containment works projects through the use of prestressed anchorages is in determining the load capacity of the ties related to the reinjection criteria. The geotechnical properties used in the project do not always represent the reality for the type of soil in the worked region, making the amount of cement injected inaccurate. The soil-bulb load transfer, in retaining works, is dimensioned by methodologies that do not fit the reality of the soil parameters in loco, making it essential to carry out tests on tie rods to prove their performance and in terms of meeting the specifications of project. This study aims to analyze the load capacity in prestressed anchorages of a cable-stayed curtain through the number of injection phases, located in a slope stability work in the municipality of São Miguel Arcanjo, southwest of São Paulo. Depending on the characteristics of the massif, the anchorages made using steel cords were evaluated through the injection pressures according to the soil resistance and the number of reinjections, verifying their performance according to receiving tests according to the ABNT-NBR 5629 standard. (2018). Evaluating that for each type of soil and for each type of work to be carried out there is an injectability limit, and the best limit should be compatible with the mechanical resistance of the soil to which the tie will be executed, demonstrating that the injection in a single phase can be adopted for solids with high support capacity, making the technical-economic relationship of the work possible through the number of injections.