Pressuremeter test in permafrost on the Qinghai-Tibet plateau

In-situ preboring pressuremeter tests were conducted on the Qinghai-Tibet Plateau to investigate the mechanical behavior of permafrost along the Qinghai-Tibet Highway. The in-situ pressuremeter test data are analyzed in this paper. Three mechanical characteristic parameters of permafrost are obtained in the test (the initial horizontal pressure P-0, the critical plastic load P-e and the limit pressure P-f), and then the pressuremeter modulus E and the shear modulus G are calculated. The relationships between the pressuremeter test parameters and their influencing factors (soil temperature and water content) are discussed. Results show that the short-term strength parameters of the frozen soils vary linearly with water content and soil temperature.