Specimen Preparation Methods for Artificially Cemented Sand in Simple Shear and Hollow Cylinder Apparatuses

Abstract

Abstract. Portland cement can be mixed with sand to improve its mechanical characteristics. Considering the inherent anisotropy of most sands, it is not clear whether the added cement shall contribute to equal increases in strength and sti ness in vertical and horizontal directions or not. Literature review reveals that all the previous experimental studies on the cement-treated soil topics are limited to conventional triaxial device test results. The e ect of cement addition to clean sand in more sophisticated stress-path controlled devices like \Simple Shear Apparatus" (SSA) and \Hollow Cylinder Apparatus" (HCA) for simulating more realistic loading conditions, such as earthquake, have not been investigated yet. This paper presents innovative methods for testing arti cially cemented sands through making modi cations to the loading platens, specimen molds, and specimen preparation methods of SSA and HCA. Undrained tests under di erent monotonic stress paths were carried out on di erent mixtures of Portland cement with clean sand to investigate the e ect of principal stress rotations. The test results revealed that the cement mixture reduces the anisotropy, while it improves the mixture mechanical properties compared to the compacted uncemented sand.

Influences of initial anisotropy and principal stress rotation on the undrained monotonic behavior of a loose silica sand

“…It is a uniformly graded sand manufactured industrially using rock crusher. Firuzkuh sand has been extensively used in different research studies focusing on liquefaction, anisotropy, sand-rubber mixtures and cemented sands and interface testing (e.g., Fakharian et al 2018, Fakharian and Vafaie 2021, Fakharian and Ahmad 2021. The basic physical properties of Firuzkuh sand are shown in Table 1, showing a mean grain size of 0.22 mm, and it is susceptible to liquefaction when sheared in loose undrained condition.…”