Assessment of Several Interpreted Pile Capacity Criteria for Large-Diameter Open-Ended Piles

2020 ◽  
Vol 44 (5) ◽  
pp. 20200074
Author(s):  
Antonio Kodsy ◽  
Nikolaos Machairas ◽  
Magued G. Iskander
Keyword(s):  
Large Diameter ◽  
Pile Capacity

Construction Method and Numerical Analysis on the Bearing Capacity of the Large Diameter and Abyssal Pile Located in Complex Karst Area

2013 ◽  
Vol 639-640 ◽  
pp. 688-693
Author(s):  
Jin Yi ◽  
Guo Jing He ◽  
Si Si Liu ◽  
Zhi Yong Li ◽  
Zu En Zheng
Keyword(s):  
Bearing Capacity ◽  
Load Transfer ◽  
Large Diameter ◽  
Construction Method ◽  
Karst Area ◽  
Karst Region ◽  
Pile Capacity ◽  
Construction Methods ◽  
Geological Conditions ◽  
Transfer Method

This paper introduced construction method for deep pile of Zishui bridge through karst region and the checking results of the pile bearing capacity. Firstly, main structure of Zishui bridge was simply introduced. Secondly, according to the special geological conditions, construction methods for bored piles in water and drilling platform were described. The discussion focused on the problem of boring and grouting in karst foundation and their solutions. Finally, to ensure that the pile capacity can meet the design requirements, load transfer method was used on the part of pile foundation to calculate the bearing capacity. Results showed that pile bearing capacity meet the requirements, and the feasibility and correctness of construction method of Zishui bridge was also verified,which provides references for the design and construction of the same civil engineering.

Axial Pile Capacity of Large Diameter Cylinder Piles

2008 ◽  
Author(s):  
Peter Lai ◽  
Michael McVay ◽  
David Bloomquist ◽  
Dhuruva Badri
Keyword(s):  
Large Diameter ◽  
Pile Capacity

scholarly journals Large-diameter helical pile capacity – torque correlations

2017 ◽  
Vol 54 (7) ◽  
pp. 968-986 ◽  
Author(s):  
Jared Harnish ◽  
M. Hesham El Naggar
Keyword(s):  
Large Diameter ◽  
Failure Criteria ◽  
Load Test ◽  
Ultimate Capacity ◽  
Pile Capacity ◽  
Shearing Resistance ◽  
Helical Piles ◽  
Torque Capacity ◽  
Load Tests ◽  
Pile Load Tests

Large-diameter helical piles are utilized increasingly to support heavy structures. Both the magnitude of the required installation torque and the pile capacity can be directly attributed to the soil shearing resistance developed over the embedded area of the pile including the shaft and helical plates. Hence, the pile capacity can be correlated to installation torque. Such correlations are widely used in the helical pile industry as a means for quality control and quality assurance. In the current study, a total of 10 test piles were installed while monitoring the installation torque continuously with depth. The recorded installation torque profiles were demonstrated to be accurate and repeatable. Field pile load tests were conducted and their results were analyzed to determine the interpreted ultimate capacity of the test piles. The results demonstrate that the ultimate capacity of large-diameter helical piles can be interpreted from pile load test data employing the failure criteria proposed by Elkasabgy and El Naggar in 2015 and Fuller and Hoy in 1970. The measured installation torque and corresponding ultimate capacity values were employed to define torque–capacity correlation (Kt) based on embedded pile area. It was demonstrated that the proposed Kt is suitable for large-diameter helical piles.

Set-Up of Large Diameter Driven Pipe Piles in Deepwater Normally Consolidated High Plasticity Clays

2009 ◽  
Author(s):  
Rathindra N. Dutt ◽  
Clarence J. Ehlers
Keyword(s):  
Wave Equation ◽  
West Africa ◽  
Gulf Of Mexico ◽  
Large Diameter ◽  
Offshore Structures ◽  
High Plasticity ◽  
Mooring Lines ◽  
Pile Capacity ◽  
Trial And Error Method ◽  
Set Up

This paper will show on the basis of hindcast wave equation analysis that soil-pile set-up for large diameter driven pipe piles in clay is faster than what the current state-of-practice utilizes for design. Results of hindcast wave equation analyses utilizing observed blowcounts and hammer energy records from two deepwater sites, one in West Africa and the other one in the Gulf of Mexico, are presented to support this conclusion. For offshore structures, this increase in the rate of soil-pile set-up reduces foundation/anchor costs or reduces the waiting time until topsides can be set on the structure or mooring lines can be hooked up to anchors. Hindcast wave equation analyses were performed utilizing the observed blowcount and hammer energy information from two deepwater West Africa and Gulf of Mexico locations where pile driving was stopped and then restarted after a few days. This is a trial and error method of analysis where the soil resistance to driving (SRD) was varied until a good match was obtained between the observed blowcount at the startup of driving and the reported hammer energy using the GRLWEAP wave equation program. The set-up time for the piles ranged from about one to twelve (12) days and the piles ranged from 2134 mm to 2743 mm diameter open-ended pipe piles. The soils generally consisted of normally to slightly overconsolidated highly plastic clays. For the purpose of computing pile set-up, the ultimate pile capacity was computed using the API RP 2A (2000) guidelines. Results show that 60 to 80 percent of the ultimate pile capacity is mobilized in about 7 days, and the extrapolation of the set-up model suggests that the set-up is almost complete in about 60 days.

scholarly journals The impact of scour on the lateral resistance of wind turbine monopiles: an experimental study

2020 ◽  
Author(s):  
Qiang Li ◽  
Amin Askarinejad ◽  
Kenneth Gavin
Keyword(s):  
Numerical Models ◽  
Large Diameter ◽  
Offshore Wind ◽  
Soil Reaction ◽  
Pile Capacity ◽  
Moment Capacity ◽  
Scour Hole ◽  
Waves And Currents ◽  
Laterally Loaded ◽  
The Impact

The majority of offshore wind structures are supported on large-diameter, rigid monopile foundations. These piles may be subjected to scour due to the waves and currents that causes a loss of soil support and consequently decreases the pile capacity and system stiffness. The results of numerical models suggest that the shape of the scour-hole affects the magnitude of pile capacity loss, however, there is a dearth of experimental test data that quantify this effect. This paper presents a series of centrifuge model tests on an instrumented model pile that investigates the effects of scour-hole geometry on the response of a laterally loaded pile embedded in sand. The pile instrumentation allowed load-displacement and p-y (soil reaction-displacement) curves to be derived. Three scour geometries (global, local wide and local narrow) and three scour depths (1D, 1.5D and 2D; where D is pile diameter) were modelled. For all three scour types, pile moment capacity decreased almost linearly with increase of scour depth. Simple empirical relations were proposed to evaluate the detrimental influence of scour on the pile moment capacity. A new method has been developed to allow designers to quantify the effect of scour-hole shape and severity of scour on the pile response.

Development of a digital SEM

1991 ◽  
Vol 49 ◽  
pp. 358-359
Author(s):  
A. Yamada ◽  
A. Shibano ◽  
K. Harasawa ◽  
T. Kobayashi ◽  
H. Fukuda ◽  
...  
Keyword(s):  
Large Diameter ◽  
Objective Lens ◽  
Large Specimen ◽  
Backscattered Electrons ◽  
Digital Scanning ◽  
Junction Type ◽  
High Resolution Images ◽  
Working Distance ◽  
Type Detector ◽  
Short Working

A newly developed digital scanning electron microscope, the JSM-6300, has the following features: Equipped with a narrower conical objective lens (OL), it allows high resolution images to be obtained easily at a short working distance (WD) and a large specimen tilt angle. In addition, it is provided with automatic functions and digital image processing functions for ease of operation.Conical C-F lens: The newly developed conical C-F objective lens, having low aberration characteristics over a wide WD range, allows a large-diameter (3-inch) specimen to be tilted up to 60° at short WD, and provides images with low magnifications starting at 10*. On the bottom of the lens, a p n junction type detector is provided to detect backscattered electrons (BE) from the specimen. As the narrower conical 0L increases the secondary electron (SE) detector's field intensity on the specimen surface, high SE image quality is obtained.

CALCULATION OF STAGES OF THE TECHNOLOGICAL PROCESS OF MANUFACTURE OF PPD DETECTORS USING COMPUTER MATHEMATICAL MODELING AND PRODUCTION OF ALPHA RADIOMETER ON THEIR BASIS

2020 ◽  
Vol 7 (2) ◽  
pp. 21-28
Author(s):  
SALI RADZHAPOV ◽  
◽  
RUSTAM RAKHIMOV ◽  
BEGJAN RADZHAPOV ◽  
MARS ZUFAROV
Keyword(s):  
Mathematical Modeling ◽  
Technological Process ◽  
Block Diagram ◽  
Large Diameter ◽  
Silicon Detector ◽  
Digital Processing ◽  
Main Element ◽  
Alpha Radiation ◽  
Initial Silicon ◽  
Natural Isotopes

The article describes the developed radiometer for Express measurement of alpha radiation of radioactive elements based on a large-diameter silicon detector. The main element of the PPD detector is made using computer mathematical modeling of all stages of the technological process of manufacturing detectors, taking into account at each stage the degree of influence of the properties of the initial silicon on the electrophysical and radiometric characteristics of the detector. Detectors are manufactured for certain types of devices. The developed radiometer is designed to measure alpha radiation of natural isotopes (238U, 234U, 232Th, 226Ra, 222Rn, 218Po, 214Bi, etc.) in various environments. It also shows the principle of operation of the device, provides a block diagram of the measuring complex, describes the electronic components of the radiometer, as well as the block diagram. Signal transformations (spectrum transfer, filtering, accumulation) are implemented programmatically on the basis of a digital processing module. The device can detect the presence of specific elements in various environments, as well as protect people from the harmful effects of adverse radiation and can be used both in the field and stationary.

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