Behavior of braced excavation supported by panels of deep mixing columns

Abstract

This paper describes the instrumentation, execution and performance of two full-scale tests where a braced steel sheet pile wall interacting with rows of overlapping dry deep mixing columns was excavated and then loaded to failure. The purpose of these tests was to provide knowledge of the behavior of deep mixing column rows located in passive zone and interacting with a retaining structure. Both tests were extensively instrumented on the active as well as on the passive side of the retaining structure. In both conducted tests a stability failure of the retaining structure occurred, resulting in heave at the bottom of the excavation and large settlements of the ground surface behind the sheet pile wall. For a spacing between LC-panels of 3.0 m a very brittle failure developed suddenly in the clay between the panels with small deformations prior to failure. In the second test, with a spacing of 1.5 m between LC-panels, the failure developed in the LC-panels as well as in the clay between the panels.Even if a similar failure mechanism developed, measured horizontal displacements, horizontal stresses, and pore pressure response prior to failure differed between the tests.The two full-scale tests were performed on an unexploited open field, located in the eastern part of Sweden, about 70 km northwest of Stockholm in the proximity of the town of Enköping. The test field, with a size of about 100x200 m, was relatively flat with an elevation

Performance of Diaphragm Walls during Ultra-Deep Excavations in Karst Areas: Field Monitoring Analysis

“…Numerous studies have been conducted to investigate the performance of excavations [10][11][12][13][14][15][16][17][18]. These studies utilized theoretical analysis, physical model tests, numerical simulations, and field monitoring.…”

Evaluation of Stability of Embankment Constructed on Soft Consolidating Soil with Lime–CFG Composite Column System

“…It has larger equivalent stiffness and hence reduces the vertical stresses in the soft soil. Combinations of lime and CFG [4][5][6], lime and cement [7,8], lime and fly ash [9], soil and cement [10][11][12], lime, soil and cement [5] are few of the composite materials suggested for columns. One such technique of composite system consists of lime column and CFG column.…”