6.6 Buried structures

Earth pressures acting on buried pipes were carefully measured at Osaka City University. Three types of pipe with different rigidity (Photo 1) were used in the tests. Special earth pressure cell was developed in order to measure the earth pressure around the pipe as shown in Fig. 1. In this test series, the variation of the earth pressure due to sheet pile wall extraction was investigated (Fig. 2).

 

Photo 1 Pipe models (flexible, medium and rigid pipes)

 

Photo 2 Testing system

 

Fig. 1 Schematic view of pipe model

 

Fig. 2 Change in normal and tangential earth pressure during sheet-pile extraction

 

References

Tohda, J., Yoshimura, H., Morimoto, T. and Seki, H. (1990) : Earth pressure acting on buried flexible pipes in centrifuged models, Proc. of ASCE Int. Conf. on Pipeline Design and Installation, pp. 17-31.

Tohda, J., Li, L. and Yoshimura, H. (1994) : Analysis of the factors in earth pressure and deformation of buried flexible pipes through centrifuge model tests, Proc. of 2nd Int. Symp. on Buried Plastic Pipe Technology, ASTM, pp. 180-194.