scholarly journals Plane strain – contact stress distribution beneath a rigid footing resting on a soft cohesive soil

1980 ◽  
Vol 17 (1) ◽  
pp. 114-122 ◽  
Author(s):  
A Patrick ◽  
S Selvadurai ◽  
R. Harland Kempthorne

This note presents an experimental study of the plane strain – contact stress distribution beneath a rigid footing resting on a compacted soft cohesive soil medium. The immediate contact stress distribution was found to be highly dependent on the magnitude of the applied stress relative to the ultimate bearing capacity of the foundation. At low levels of applied stress the contact stresses were substantially higher at regions adjacent to the footing edges. As the applied stresses were increased, the contact stresses achieved a more uniform configuration.

1983 ◽  
Vol 20 (3) ◽  
pp. 406-415 ◽  
Author(s):  
A. P. S. Selvadurai ◽  
S. A. A. Rabbaa

This paper presents an experimental study of the contact stress distribution beneath two interfering rigid strip foundations resting in frictionless contact with a layer of dense sand underlain by a smooth rigid base. It is found that the interference between the two foundations has a significant influence on the contact stress distribution. In the absence of interference, the contact stress distribution beneath a single foundation exhibits a symmetrical shape. As the spacing between the foundations diminishes the contact stress distribution exhibits an asymmetrical shape. Keywords: contact stresses, foundation interference, plane strain tests, experimental studies.


2011 ◽  
Vol 211-212 ◽  
pp. 535-539
Author(s):  
Ai Hua Liao

The impeller mounted onto the compressor shaft assembly via interference fit is one of the key components of a centrifugal compressor stage. A suitable fit tolerance needs to be considered in the structural design. A locomotive-type turbocharger compressor with 24 blades under combined centrifugal and interference-fit loading was considered in the numerical analysis. The FE parametric quadratic programming (PQP) method which was developed based on the parametric variational principle (PVP) was used for the analysis of stress distribution of 3D elastoplastic frictional contact of impeller-shaft sleeve-shaft. The solution of elastoplastic frictional contact problems belongs to the unspecified boundary problems where the interaction between two kinds of nonlinearities should occur. The effect of fit tolerance, rotational speed and the contact stress distribution on the contact stress was discussed in detail in the numerical computation. The study play a referenced role in deciding the proper fit tolerance and improving design and manufacturing technology of compressor impellers.


Author(s):  
J. Groenendijk ◽  
C. H. Vogelzang ◽  
A. A. A. Molenaar ◽  
B. R. Mante ◽  
L. J. M. Dohmen

The relative strain effects of 15 different load configurations were studied. Using the linear tracking device (LINTRACK) accelerated loading facility, two 5-year-old pavements of 0.15-m asphalt on sand (one virgin and one loaded with 4 million 75-kN wheel loads) were tested. All measured strains were converted to strain factors relative to a standard load (super-single tire, 50 kN, 0.70 MPa). The results were compared with earlier measurements and BISAR-calculated factors. The results on the loaded pavement showed markedly more variation than those on the unloaded pavement. Generally, the BISAR-calculated relative strain factors matched the measured values well for the super-single tire. Considerable difference occurred only in the most extreme load conditions. Nonuniform contact stress distribution can be the cause for this. The calculated relative strain factors for the dual tire configurations underestimated the measured values.


Author(s):  
Sherif Mohareb ◽  
Arndt Goldack ◽  
Mike Schlaich

Cable-stayed and extra-dosed bridges are today widely used bridge types. Recently, saddles have been used to deviate strands of cables in the pylons. Up to now the mechanics of strands on saddles are not well understood. It was found, that typical longitudinal contact stress distributions between strand and saddle show a strong nonlinearity and a high peak value around the detachment point, where the strand meets the saddle. This paper presents a procedure to analyse the longitudinal contact stress distribution obtained by FEM calculations: This contact stress can be idealised as a constant contact stress according to the Barlow's formula and a contact force at the detachment point due to the flexural rigidity of the bent tension elements. An analytical model is provided to verify this contact force. Finally, a formula is presented to calculate the maximum contact stress. This study provides the basis for further research on saddle design and fatigue of strands.


Sign in / Sign up

Export Citation Format

Share Document