岩溶地区嵌岩桩桩端岩体临空面稳定性初步探讨

DISCUSSION ABOUT THE STABILITY OF ROCK MASS FREE FACE ON THE TIP OF ROCK-SOCKED PILE IN CARST REGION

岩溶地基突出问题不是地基强度而是地基稳定性,尤其是桩端岩体临空面稳定性。通过极端岩体临空面半定量分析评价及深井静载荷试验,发现当前岩土工程中一些理论不甚合理。经过研究分析,认为桩端应力影响范围内,结构较为完整的岩体临空面,在无外倾结构面和桩端受力小于岩基承载力的情况下,稳定性良好。由于这一观念的转变,对实际工程可产生很大的经济效益。

The key problem of karst foundation is not the foundation strength itself but the foundation stability, especially the stability of the free face of rock mass on the pile tip. Though there are semiquantitative analysis and appraisement, and dead load test for deep well, it is found that there are still some theoretical irrationalities in the current geoengineering. The authors believe that if the structure of the rock mass is comparatively intact and the load of the tip of pile is less than the bearing cpacity of the batholith of the rock mass in the pile tip, the free face will be stable. Owing to this idea, there will be many economical benefits for engineering.