Lime stabilization has been widely used in pavement subbases and ground improvement, but the investigation of the mechanical properties and the microstructure of lime stabilized loess is still insufficient.

This paper describes a design framework for inclined tensile loading capacity (holding capacity) of dynamically installed anchors in soft clay. Centrifuge model test and numerical results indicate that, while ultimate inclined holding capacity increases with a loading angle smaller than 45° (to the vertical at anchor padeye), anchor failure is controlled predominantly by the ultimate vertical holding capacity, which can be predicted using the American Petroleum Institute method put forth in 2007 with interface friction ratio of 0.25–0.34 and 0.60–0.82 for short- and long-term conditions, respectively. For a loading angle larger than about 65°, anchor failure is controlled largely by the ultimate horizontal holding capacity. It is proposed herein that the ultimate lateral holding capacity can be estimated by generalizing Broms’ method put forth in 1964 for lateral anchor capacity to variable cross section; thereby allowing anchor geometry to be considered in a rational manner. Good agreement can be obtained between the estimated ultimate horizontal holding capacity and that computed using the finite element method by using a lateral resistance of 10.5s_u, where s_u is the undrained shear strength. For a loading angle between 45° and 65°, there is significant interaction between vertical and horizontal failure modes. This allows a normalized horizontal–vertical interaction curve to be defined by fitting data from this and previous studies.

Loess is a typical collapsible soil, which is widely distributed in the upper and middle areas around the Yellow River of China. The stabilization of loess with lime provides a significant improvement in the physical and the mechanical characteristics of the loess and is therefore widely used in the pavement base and subgrade. Therefore, a systematic investigation of Mohr-Coulomb failure envelope of lime stabilized loess needs to be conducted. In this pursuit, the present research envisages the investigation of the effects of the lime content, porosity and curing time on the strength parameters (friction angle (φ) and cohesion (c)), using a series of triaxial tests performed on lime stabilized loess specimens. The experimental results revealed that the friction angle (φ) was independent of the lime content, the porosity and the curing time of the specimen for a given lime stabilized loess, while the factors mentioned above had a significant effect on the cohesion (c) of the lime stabilized loess. For a relatively short curing time (7 days), the change in the lime content did not present an obvious effect on the cohesion (c) of the stabilized loess. However, when the curing time (28, 90 and 180 days) was longer, the increase of the lime content significantly enhanced the cohesion of the stabilized loess. When the lime content was constant, the cohesion (c) of the stabilized loess increased linearly with the decrease in the void ratio. A power function equation was proposed to assess the comprehensive influences of the factors like the lime content, porosity and curing time on cohesion (c). Finally, the Mohr-Coulomb failure envelopes were drawn based on the triaxial test for 47 specimens with various curing time and confining pressure, and the shear strength parameters obtained by the proposed equation were also compared with the experimental results.