Load Test Program to Validate Model for Post Grouted Drilled Shafts

2007 ◽  
Author(s):  
Americo L. Fernandez ◽  
Miguel A. Pando ◽  
Philip G. King
Keyword(s):  
Drilled Shafts ◽  
Load Test ◽  
Test Program

Suitability of jetted and grouted precast pile for supporting mast arm structures

2017 ◽  
Vol 54 (9) ◽  
pp. 1231-1244 ◽  
Author(s):  
Sudheesh Thiyyakkandi ◽  
Michael McVay ◽  
Peter Lai ◽  
Rodrigo Herrera
Keyword(s):  
Test Chamber ◽  
Field Tests ◽  
Load Resistance ◽  
Lateral Load ◽  
Urban Environments ◽  
Drilled Shafts ◽  
Load Test ◽  
Lateral Loading ◽  
Wind Loading ◽  
Test Program

Jetted and grouted precast piles (JGPPs) are prefabricated piles installed utilizing jetting and pressure grouting. These piles are well-suited for urban environments as they overcome the inherent drawbacks of currently chosen deep foundations (e.g., noise and vibration disturbances due to pile driving, quality control issue with cast-in-place construction). Past studies in a large test chamber facility have shown that JGPPs can support very high axial and torsional loads owing to their improved skin and tip resistances subsequent to the side- and tip-grouting. However, this new pile has not yet been implemented in practice due to the lack of field verification of its constructability as well as load resistance. This paper presents the full-scale field construction of two JGPPs and the load test program performed to investigate the applicability of the new pile as a foundation for miscellaneous structures. As such structures are subjected to high torsion and lateral load during severe wind-loading (e.g., hurricanes), the test program included combined torsion and lateral loading as well as simple lateral loading. An actual pole – mast arm assembly was used in the coupled torsion and lateral load test to simulate the typical field-loading scenario. The load was applied using a crane and the pile’s rotations and translations were monitored using the novel instrumentation systems. The field tests showed that JGPPs possess high torsion and lateral resistances compared to identically sized drilled shafts, which is a common foundation type used for such structures. The two methods available for predicting axial resistance of the new pile are found to be suitable for the estimation of torsional resistance as well. It was also found that the concurrent application of torsion significantly reduces lateral resistance of the new pile foundation as observed for drilled shafts. In general, the study reveals that the JGPPs are well-suited foundations for miscellaneous structures.

Behaviour of friction piles in soft sensitive clays

1980 ◽  
Vol 17 (2) ◽  
pp. 203-224 ◽  
Author(s):  
R. Blanchet ◽  
F. Tavenas ◽  
R. Garneau
Keyword(s):  
Precast Concrete ◽  
Soft Clay ◽  
Load Test ◽  
Pile Groups ◽  
Test Program ◽  
Shear Creep ◽  
Soft Clays ◽  
The North ◽  
Effective Stress Analysis

During the construction of heavy structures, such as bridges and overpasses, on soft clays on the north shore of the St. Lawrence Valley, a detailed load test program on friction piles was performed to establish the characteristics of the most suitable type of pile and to study its long-term behaviour. Three types of piles, timber, steel pipe with closed end, and precast concrete Herkules H-420 piles, were tested. Four timber piles driven in a group and submitted to a 712 kN load served to study the long-term settlement of a small group of piles. Three deep settlement gauges were installed in the centre of this group for measuring settlements in clay at various depths.This test program was completed by the instrumentation of two bridge piers in order to verify the behaviour of larger groups of piles.The paper presents the results of the test piles, the long-term behaviour (4 years) of the bridge pier foundations resting on friction piles in soft clay, and the interpretation of the results.This study shows that the pore pressures induced by pile driving are related to the pre-consolidation of the clay and that they are much larger for tapered piles. It is demonstrated that the effective stress analysis method proposed in 1976 by Meyerhof determines adequately the ultimate pile bearing capacity, but that the effect of the timber pile taper doubles the skin friction.The settlement analysis of pile groups shows that settlements are due to the reconsolidation of the clay and shear creep deformations in the clay close to the pile wall.

Louisiana Highway 1 Pile Load Test Program

2008 ◽  
Author(s):  
Sanjoy Chakraborty ◽  
Michael W. Montgomery
Keyword(s):  
Load Test ◽  
Test Program ◽  
Pile Load Test

scholarly journals Behaviour of Single and Group Helical Piles in Sands from Model Experiments

2019 ◽  
Vol 278 ◽  
pp. 03007
Author(s):  
Jongho Bak ◽  
Byung-hyun Choi ◽  
Junwon Lee ◽  
Jonghwan Bae ◽  
Kicheol Lee ◽  
...  
Keyword(s):  
Rotation Speed ◽  
Axial Loading ◽  
Complete Removal ◽  
Drilled Shafts ◽  
Load Test ◽  
Oil Sand ◽  
Driven Piles ◽  
Pile Installation ◽  
Helical Piles ◽  
Pile Load Tests

Mainly used foundations of oil sand plants are drilled shafts or driven piles. As environmental regulations become increasingly strict, complete removal of the foundation is becoming more important during the step of plant dismantling. However, it is difficult to remove completely drilled shafts or driven piles which are deeply installed to obtain more bearing capacity. Helical piles can be easily removed and recycled after use. This study analyses the behaviour of single and group helical piles in sands. For single helical piles, pile load tests of helical piles were conducted varying helix spacing, rotation speed and weight of axial loading during pile installation. The single pile tests determined the optimal helix spacing, rotation speed, weight of axial loading during pile installation. And then, pile load test of group helical piles was performed varying pile spacing from the centre place of upper connector based on the optimal installation conditions.

Predesign Foundation Load Test Program for US-17 (Wilmington) Bypass over Northeast Cape Fear River

2000 ◽  
Vol 1736 (1) ◽  
pp. 19-23
Author(s):  
Scott Hidden ◽  
Nariman Abar
Keyword(s):  
North Carolina ◽  
Cost Savings ◽  
Load Test ◽  
Test Program ◽  
Foundation Design ◽  
Significant Cost ◽  
Concrete Piles ◽  
Cape Fear River ◽  
Cape Fear ◽  
Side Friction

The North Carolina Department of Transportation is currently conducting a predesign foundation load test for a new bridge over the Northeast Cape Fear River near Wilmington, North Carolina. The primary purpose of the load test program is to determine whether concrete piles can penetrate a very dense and cemented sand layer and what side friction and tip bearing capacities should be used for the design of the drilled piers. Significant cost savings could be realized if pile foundations instead of drilled piers could support the approach spans of the bridge. For this determination, three concrete piles will be installed 30 m into the ground. Significant cost savings could also be realized by making a more accurate determination of the drilled pier capacities. For this determination, the side friction and tip bearing capacities of the dense Peedee sands and the underlying hard marine clays will be determined with Osterberg cell tests on two 2130-mm-diameter drilled piers. The different subsurface layers (muck, alluvial sands, and Peedee sands) will also be tested laterally with both static and statnamic testing to assist in the foundation design. The load test program incorporates an NCHRP research program on pile groups. The program includes testing a reusable instrumented steel pile group and frame at various sites in various soil conditions around the United States. The load test program results to date, the effect of the results on the foundation design, and the construction, testing, and instrumentation of the drilled piers are described.

Development and Application of Engineering Vehicle Transmission Load Test System

2011 ◽  
Vol 105-107 ◽  
pp. 2019-2023
Author(s):  
Li Chao Xu ◽  
Ru Hai Ge
Keyword(s):  
High Sensitivity ◽  
Test System ◽  
Drive Shaft ◽  
Load Test ◽  
Telemetry System ◽  
Test Program ◽  
Powertrain System ◽  
Shaft Torque ◽  
Torque Values ◽  
The Given

Transmission load was one of the important parameters for engineering vehicle powertrain system, on the basis of calculating drive shaft torque values and ascertaining the measurement point positions, we selected resistance strain guages to design torque sensors and also chose a signal telemetry system, after using a self-made torque calibration bench to statically calibrate torque sensors, we developed a test system for loader drive shaft load. According to the given test program, we performed an actual loader experiment to measure torque at the loader drive shaft measurement points and analyzed the test waveforms. The results of bench calibration and actual loader test showed that the designed torque sensors had a high sensitivity and a good linearity, and the developed test system was correct and effective.

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