
RESULTS OF COMPRESSION TESTING ON PSEUDO-COHESIVE SOIL
Author(s) -
Вадим Офрихтер,
Yan Ofrikhter
Publication year - 2015
Publication title -
vestnik mgsu
Language(s) - English
Resource type - Journals
eISSN - 2304-6600
pISSN - 1997-0935
DOI - 10.22227/1997-0935.2015.9.61-72
Subject(s) - cohesion (chemistry) , void ratio , materials science , geotechnical engineering , void (composites) , creep , soil water , compression (physics) , hardening (computing) , compression test , composite material , mathematics , geology , soil science , physics , layer (electronics) , quantum mechanics
Natural non-treated sand reinforced with randomly oriented short polypropylene fibers of 12 mm in length was tested to determine creep characteristics. This study is a part of the research aimed at encouraging fibrosand (FRS) application in subsoils, embankments and retaining wall constructions. Fiber content was accounted for 0.93 %. Twin specimens were put to creep tests (1-D compression) using the two curve method. The test results were analyzed and checked with the use of ageing, hardening and hereditary creep theories. On the basis of approximation of the test results the creep deformation equation at constant stress for tested fibrosand was obtained. The assessment of fibrosand secondary compression was carried out by the FORE method. As a result, the value of the void ratio by the end of the secondary compression had been eu=0.7041. For determination of the beginning of the secondary compression the rate equation was superimposed on the empirical curve. The point of the graph divergence is the beginning of the secondary compression process. The secondary compression had begun by the time moment being equal to 9360 min. The void ratio by the beginning of the secondary compression had amounted to 0.70574. Fibrosand is a specific type of improved soil relating to so-called pseudo-cohesive soil. This type of soil is characterized by cohesion like cohesive soils, but, at the same time, by the filtration coefficient of about 1 m per day like non-cohesive soils. Pseudo-cohesive soil testing helps to understand the distinctive features of the stress-strain state of this kind of materials. Municipal solid waste also relates to them.