Estimation of Micropile Capacity Grouted under Pressure
[1]
H. Elarabi, Building and Road Research Institute, University of Khartoum, Khartoum, Sudan.
[2]
M. Alhadi Alshareef, Building and Road Research Institute, University of Khartoum, Khartoum, Sudan.
The aim of this paper is to study the behavior of micropile type B where neat cement grout is placed into the hole under pressure. Numerical analysis is used to simulate this behavior. The model was verified against field test data performed on Khartoum soil. These models are introduced briefly, and then used to investigate the effect of pressure grouting on micropile. For micropiles of diameter less than 25cm a considerable increase in their capacities was deduced due to increase in pressure. For any diameter larger than 30cm it is expected that, the pressure will have no effect on increasing the pile diameter and thus the capacity of pile. This why micropiles diameter are assumed ≤ 30cm. Though the factor (f) for micropiles with diameters greater than 10cm and less than 20cm can be estimated using certain equation developed in this study. The results of the developed model are in good agreement with the experimental results.
Micropile, Finite Element, Grouting, Failure Load, Cohesive Soil
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