Experimental Research Of Work Mechanism On Pile With Prestressed Anchor And Composite Soil Nailing Supporting System

Pile with prestressed anchor and composite soil nailing supporting system has been widely used in some areas of the country. But the working mechanism of the system is relatively complex. When prestressed anchor and soil nail are applied together, prestressed anchor play an active part in the system and soil nail play an passive part. At present both of them how to work together is still not clear.There is no unified design theory and the existed theory lag far behind the situation of practice.This test combine with the foundation pit engineering in Henan zone doing the in situ test, researching the pile with prestressed anchor and composite soil nailing supporting system on the site full scale. It make use of fiber optic distributed strain and temperature sensor measuring technology monitoring stress and strain distribution of soil nail and prestressed anchor. And research the stress and strain changing of soil nail and prestressed anchor with the excavation process of the pit.Based on theory design and practical monitoring of engineering,we analyze the force and deformation of pile with prestressed anchor and composite soil nailing supporting system in the actual engineering to research the working mechanism of the supporting system.In this paper, the main ideas include that,(1) Introduce the present study and development status of composite soil nail system and pile anchor composite soil nailing support system from the cognition composite soil nailing support;(2) Introduce the structure of pile with prestressed anchor and composite soil nailing supporting system;(3)Combine with the foundation pit engineering of the countries clinical research base of henan traditional Chinese medicine science institute doing the in situ test;(4)According to the test results of pile with prestressed anchor and composite soil nailing supporting system in situ test to research the experiment work mechanism of this supporting system. The highlighting research priorities are distribution and changes in law of internal force as the foundation pit excavation, prestressed anchor’s stretch-draw and rainfall changes; Explore the interactions between soil nail and anchor; Point out the grouting effect on slope soil physical parameters and on the changes of potential slide surface crack;(5) Do a detailed analysis about construction process and main technical points of the pile with prestressed anchor and composite soil nailing supporting system. Expound treatment method with extraordinary circumstances in the construction process in this paper. They have an important guiding significance to the similar design and construction.