Rig Jacking on Soft Soil Foundations: Improvements in Safety and Speed by Monitoring Leg Loads

1983 ◽  
Vol 105 (2) ◽  
pp. 201-204
Author(s):  
P. F. Ansquer ◽  
S. A. Antalovsky
Keyword(s):  
Continuous Monitoring ◽  
Soft Soil ◽  
Soil Conditions ◽  
Soil Reaction ◽  
Monitoring And Control ◽  
Reaction Forces ◽  
Structural Stresses ◽  
The Stability ◽  
And Control ◽  
Jack Up

The stability of jack-up rigs with spud-cans, particularly during the jacking-up and preloading operations, has always been critical in soft soil conditions. In the offshore areas opened to prospection in Cameroon, unconsolidated clays and silts are frequent, and therefore the need to conduct these critical operations with maximum safety is of utmost importance. The monitoring of soil reactions at the spud-cans and of structural loads at the jack-houses enabled jacking operations to be conducted safely, in an area where other rigs previously encountered severe difficulties (capsizing). Data recorded by instrumentation have shown that leg maneuvering with soil penetrations of up 40 m (131 ft) may induce dangerous overloads to the structure. The continuous monitoring and control of soil reaction forces and structural loads during drilling ensured the safety of the rig. For jacking-down, the monitoring of the loads was necesary to control the structural stresses induced by the legs pulling out. To the authors’ knowledge, no similar measurements have been reported in the past.

Asset Integrity Management – Natural Gas Slug Catcher Facility

2014 ◽  
Author(s):  
D.. Williams ◽  
A.. Boodoosingh
Keyword(s):  
Natural Gas ◽  
Continuous Monitoring ◽  
Integrated Approach ◽  
Process Control System ◽  
Monitoring And Control ◽  
Operational Strategies ◽  
Maintenance System ◽  
Integrity Management ◽  
And Control ◽  
Management Report

Abstract Reliable operations of the Natural Gas {Slug catcher} Facility are heavily dependent on flawless operations and also the maintenance system implemented. The maintenance system is driven by the Asset Integrity Management System (AIMS), which incorporates corrosion control, equipment maintenance, pipeline operations and vessel inspection. This system is also supported by continuous monitoring and control using a Process Control System for the natural gas facility. This paper presents an integrated approach to operations of the Slug catcher facility based on AIMS and operational strategies, which are implemented to ensure efficient and effective operations. Additionally, recommendations for further improvement are documented based on a recent Asset Integrity Management Report.

scholarly journals Review on Lateral Stability of Piled Riverine Structures in the Estuaries of Sarawak

2018 ◽  
Vol 7 (3.18) ◽  
pp. 21
Author(s):  
Lee Lin Jye ◽  
Shenbaga R. Kaniraj ◽  
Siti Noor Linda bt Taib ◽  
Fauzan Bin Sahdi
Keyword(s):  
Soft Soil ◽  
Natural State ◽  
Soil Conditions ◽  
Silty Clay ◽  
River Bank ◽  
Soil Movement ◽  
Geotechnical Problem ◽  
Construction Activity ◽  
Lateral Soil Movement ◽  
The Stability

Soft soil conditions with very soft and deep silty clay have constantly endangered the stability of the riverine and estuarine structures in Sarawak. There have been many failures of jetties, wharves and bridges in Sarawak. In many cases of failures, the piles were not designed to resist the lateral movement, unless they were included to stabilize unstable slopes or potential landslides. This practice may be due to reasons such as erroneously judging the river bank as stable in slope stability analysis or simply due to the inexperience of designers. Also, when the river bank approaches the limiting stability in its natural state any construction activity on the river bank could result in lateral soil movement. This paper highlights this important geotechnical problem in Sarawak. Then it presents the details of a few failures of estuarine structures. A review of situations causing lateral loading of piles is then presented. The results of the in-soil and in-pile displacement measurements are shown in this paper and it is found that the computation made to compare between field and 3D modeling is agreeable.  

scholarly journals A fuzzy based parametric monitoring and control algorithm for distinctive loads to enhance the stability in rural islanded microgrids

2020 ◽  
Vol 33 (2) ◽  
pp. 227-241
Author(s):  
Fawad Azeem ◽  
Ghous Narejo
Keyword(s):  
Control Algorithm ◽  
Fuzzy Controller ◽  
Load Control ◽  
Prolonged Storage ◽  
Monitoring And Control ◽  
Skilled Manpower ◽  
Parameter Variations ◽  
Load Monitoring ◽  
The Stability ◽  
And Control

Effective monitoring and control of isolated rural microgrid in the developing world is challenging. The modern communication and monitoring is difficult to handle in such communities due to a complicated approach to the area, lack of modern facilities and unavailability of skilled manpower. Implementation of a microgrid in such areas using intermittent renewable sources and limited storage is challenging. Uncontrolled load consumption leads to the system-wide outages due to prolonged storage utilization in peak hours and is referred here as battery storage stress hours (BSSH). This research is focused to study and analyze the behavior of parametric load monitoring and control algorithm that could control the distinctive load of the microgrid during BSSH. In the proposed algorithm, the residential loads are distinctively controlled while utilizing the three locally available parameters that are the state of the charge of storage, solar irradiations and ambient temperature. In other words, the natural parameter variations have been uniquely utilized as a monitoring tool for load control. The fuzzy controller takes a decision for the activation or deactivation of any load based on the three parameters variation ranges. It is observed from the simulation and experimental results that while only utilizing locally available parameters the effective load control is possible.

scholarly journals Feedback of the behaviour of a silo founded on a compressible soil improved by floating stone columns

2018 ◽  
Vol 149 ◽  
pp. 02008
Author(s):  
Ramdane Bahar ◽  
Omar Sadaoui ◽  
Fatma Zohra Yagoub
Keyword(s):  
Soft Soil ◽  
Limit State ◽  
Soil Improvement ◽  
Stone Columns ◽  
Soil Conditions ◽  
Deep Foundations ◽  
The Stability ◽  
Compressible Soil ◽  
The City ◽  
Ongoing Monitoring

The coastal city of Bejaia, located 250 kilometers east of the capital Algiers, Algeria, is characterized by soft soils. The residual grounds encountered on the first 40 meters usually have a low bearing capacity, high compressibility, insufficient strength, and subject to the risk of liquefaction. These unfavorable soil conditions require deep foundations or soil improvement. Since late 1990s, stone columns technique is used to improve the weak soils of the harbor area of the city. A shallow raft foundation on soft soil improved by stone columns was designed for a heavy storage steel silo and two towers. The improvement of 18m depth have not reached the substratum located at 39m depth. The stresses transmitted to the service limit state are variable 73 to 376 kPa. A rigorous and ongoing monitoring of the evolution of loads in the silo and settlements of the soil was carried out during 1400 days that is from the construction of foundations in 2008 to 2012. After the loading of the silo in 2010, settlement occurred affecting the stability of the towers due to excessive differential settlements. Consequently, the towers were inclined and damaged the transporter. This paper presents and discusses the experience feedback of the behavior of these structures. Numerical calculations by finite elements have been carried and the results are compared with the measurements.

scholarly journals Classification of Actigraphy Records from Bipolar Disorder Patients Using Slope Entropy: A Feasibility Study

Entropy ◽  
2020 ◽  
Vol 22 (11) ◽  
pp. 1243
Author(s):  
David Cuesta-Frau ◽  
Jakub Schneider ◽  
Eduard Bakštein ◽  
Pavel Vostatek ◽  
Filip Spaniel ◽  
...  
Keyword(s):  
Bipolar Disorder ◽  
Continuous Monitoring ◽  
Monitoring And Control ◽  
Term Evolution ◽  
Entropy Measures ◽  
High Prevalence ◽  
Technological Developments ◽  
And Control

Bipolar Disorder (BD) is an illness with high prevalence and a huge social and economic impact. It is recurrent, with a long-term evolution in most cases. Early treatment and continuous monitoring have proven to be very effective in mitigating the causes and consequences of BD. However, no tools are currently available for a massive and semi-automatic BD patient monitoring and control. Taking advantage of recent technological developments in the field of wearables, this paper studies the feasibility of a BD episodes classification analysis while using entropy measures, an approach successfully applied in a myriad of other physiological frameworks. This is a very difficult task, since actigraphy records are highly non-stationary and corrupted with artifacts (no activity). The method devised uses a preprocessing stage to extract epochs of activity, and then applies a quantification measure, Slope Entropy, recently proposed, which outperforms the most common entropy measures used in biomedical time series. The results confirm the feasibility of the approach proposed, since the three states that are involved in BD, depression, mania, and remission, can be significantly distinguished.

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