Long term materials test program. Quarterly report, April-June 1983

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.

Download Full-text

Pulverized-Coal Transport Through Pipes

Journal of Engineering for Power ◽

10.1115/1.4008004 ◽

1959 ◽

Vol 81 (1) ◽

pp. 43-52 ◽

Cited By ~ 6

Author(s):

R. C. Patterson

Keyword(s):

Flow Characteristics ◽

General Information ◽

Pulverized Coal ◽

Steam Generators ◽

Test Program ◽

Horizontal Pipe ◽

Friction Factors ◽

Piping Systems ◽

Coal Mixtures

Some typical problems related to pulverized-coal transport for steam generators have been investigated in a long-term test program. The investigation has provided information relative to the performance of a commercial-type exhauster handling air-coal mixtures, friction factors for 8 and 12-in-diam pipe handling air-coal mixtures, general information as to the flow characteristics of air-coal mixtures in various piping systems, and methods and means for control of coal drifting in horizontal pipe. Friction factors in the range of 0.017 to 0.035 for 8 and 12-in. pipe are indicated for the usual operating range.

Download Full-text

Update of the Long-Term Inflow and Structural Test Program

42nd AIAA Aerospace Sciences Meeting and Exhibit ◽

10.2514/6.2004-500 ◽

2004 ◽

Cited By ~ 2

Author(s):

Herbert Sutherland ◽

Jose Zayas ◽

A. Sterns ◽

Byron Neal

Keyword(s):

Test Program ◽

Structural Test

Download Full-text

CONTINUOUS LONG-TERM TEST PROGRAM ON A UTILITY-SCALE WIND TURBINE

44th AIAA Aerospace Sciences Meeting and Exhibit ◽

10.2514/6.2006-1366 ◽

2006 ◽

Cited By ~ 1

Author(s):

Jose Zayas ◽

Herbert Sutherland ◽

Troy Patton

Keyword(s):

Wind Turbine ◽

Test Program ◽

Utility Scale

Download Full-text

Long-Term Reliability of Historical Monuments Built with Low Quality Sandstone

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.133-134.331 ◽

2010 ◽

Vol 133-134 ◽

pp. 331-336 ◽

Cited By ~ 1

Author(s):

Els Verstrynge ◽

Luc Schueremans ◽

Dionys Van Gemert ◽

Evert Bourel

Keyword(s):

Compressive Strength ◽

Creep Model ◽

Original Material ◽

Dead Load ◽

Test Program ◽

Long Term Stability ◽

Sustained Loading ◽

Historical Monuments ◽

Set Up

The presented research concerns the long-term stability of a series of historical monuments, which were constructed with low-strength, ferrous sandstone. The main issues are the overall low compressive strength of the sandstone, the large scatter on these strength values, the sensitivity of its characteristics to water absorption and the lack of new original sandstone to replace the damaged zones. The sandstone reacts poorly under sustained high load levels, a situation which typically occurs at the base of bell towers and medieval city towers, as the dead load is considerably high compared to the compressive strength of the sandstone material. To assess the long-term behaviour of the sandstone, a test program has been set up to obtain information on its strength characteristics under monotonic and sustained loading. Therefore, test specimens were taken from the original material of a collapsed church tower. The results of these laboratory tests were used to adapt the parameters of an existing creep model to simulate the long-term behaviour of the sandstone under specific stress levels. Additionally, a number of strengthening solutions are discussed.

Download Full-text