Experimental study on interface friction characteristics between geosynthetics and fill materials by pull out tests

Author(s):  
Qi-mao Cai ◽  
Si-fa Xu
2012 ◽  
Vol 446-449 ◽  
pp. 264-268 ◽  
Author(s):  
Wei Shi ◽  
Jin Han ◽  
Yuan Hao Jiang ◽  
Yong Bin Li

The technology of Reinforced soil has been widely used in civil engineering, its theory has some development . However, there is nearly any study about the theory of Geogrid-reinforced fly ash .In this paper, study the interface characteristics between fly ash and geogrid through the pull-out test,reach the following conclusions:the size of normal stress and water impact the interface parameters between the geogrid and fly ash;the interface friction coefficient between Geogrid and fly ash is small,adding gravel to fly ash can improve the interface friction coefficient between geogrid and fly ash.


2018 ◽  
Vol 108 (05) ◽  
pp. 353-358
Author(s):  
E. Abele ◽  
F. Ali ◽  
M. Berger

Aus Schwerzerspanung und Turbinenschaufelfertigung ist bekannt, dass Werkzeuge aus dem Spannfutter ausgezogen werden. Die veränderte Werkzeugposition führt zur Abweichung von den vorgegebenen Toleranzen und einer geringeren Fertigungsqualität oder Beschädigung des Werkstücks. Der Artikel untersucht das Auszugsverhalten verschiedener Spannfutter. Mit einem Prüfstand können die Einflüsse der mechanischen Belastung und der Klemmlänge auf die Haltekraft im Pressverband betrachtet und die Wirkmechanismen beim Auszug des Werkzeuges aus dem Spannfutter sensorisch ermittelt werden.   From heavy-duty cutting and turbine blade manufacturing it is known that tools pull out from chucks. A change in tool position leads to deviations from tolerance and decreases manufacturing quality or damages the workpiece. This article explores the extension behavior of different chucks on a specifically designed test bench. This allows determining how mechanical load and clamping length influence the holding force in the press fit and what mechanisms of action affect the extraction of the tool from the chuck.


2019 ◽  
Vol 90 (3) ◽  
pp. e17.3-e16
Author(s):  
D Akarca ◽  
A Durnford ◽  
F Ewbank ◽  
J Hempenstall ◽  
A Sadek ◽  
...  

ObjectivesExternal ventricular drain (EVD) dislodgement is common and can lead to significant morbidity and mortality. UK trial data suggests dislodgement as high as 12%. This study aimed to establish the range of methods used nationally and determine the most secure method in a porcine model.DesignSurvey and experimental study.Subjects23 neurosurgical units surveyed. Porcine cadaver experimental model.MethodsSurvey distribution was made through the British Neurosurgical Trainee Research Collaborative. 15 securement methods were tested on the porcine model and peak pull-out force before EVD failure was measured. Failure was defined as catheter displacement 1 cm from the insertion site, catheter fracture or suture fracture.ResultsNationally, five EVD securement methods were in common use. There were considerable differences in peak pull-out force between methods. The most secure methods were a construct consisting of anchoring suture, further multiple sutures around a coil of catheter followed by either a soft (25.85N, 95% CI 24.95 N-26.75N) or hard plastic flange (29.05N, 95% CI 25.69 N-32.41N). Individually, anchoring sutures, soft flanges, VentriFix and staples were least secure, whilst multiple sutures and hard flanges were most secure.ConclusionsAn anchoring suture followed by a coil of catheter and a flange is the most secure method for securing EVDs, withstanding up to 8.2 times the force of a single anchoring suture. It is easily employed and may decrease the likelihood of EVD dislodgement and associated complications.


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