scholarly journals Limitations and risk related to static capacity testing of piles – “unfortunate case” studies

2018 ◽  
Vol 146 ◽  
pp. 02006 ◽  
Author(s):  
Jarosław Rybak ◽  
Maciej Król
Keyword(s):  
Field Tests ◽  
Horizontal Displacement ◽  
Load Test ◽  
Load Testing ◽  
Key Factors ◽  
Pile Head ◽  
Load Range ◽  
Lateral Capacity ◽  
Vertical Loading ◽  
The Impact

Static load testing of foundation piles is still considered the main capacity check technology for almost any kind of piling works (bored, displacement, driven). The rates of load, time increments or imposed displacement are the key factors for various testing methods. The load-displacement relationship, which can be transformed into a coordinate system, is always the point of departure for the analysis of the results. For axis (vertical) loading, both, applied load and measured pile head settlement are examined during the entire test. During the lateral capacity tests, the horizontal displacement and inclination of free pile head is measured. In either case, all recorded values must be thoroughly examined in order to avoid systematic errors which could flaw the results of the analysis. In this paper, the authors gather and discuss their experience from field tests in which equipment malfunctions or external circumstances had the impact on the range of load test and, thus, their results. The possible ways of test extrapolation with regard to load range are also the subject of further observations presented in this publication.

Comparison of the Bidirectional Load Test with the Top-Down Load Test

2005 ◽  
Vol 1936 (1) ◽  
pp. 108-116 ◽  
Author(s):  
Oh Sung Kwon ◽  
Yongkyu Choi ◽  
Ohkyun Kwon ◽  
Myoung Mo Kim
Keyword(s):  
Load Transfer ◽  
Measurement Data ◽  
Load Test ◽  
Load Testing ◽  
Pile Head ◽  
Top Down ◽  
Simple Method ◽  
Testing Method ◽  
Settlement Behavior ◽  
Cell Test

For the past decade, the Osterberg testing method (O-cell test) has been proved advantageous over the conventional pile load testing method in many aspects. However, because the O-cell test uses a loading mechanism entirely different from that of the conventional pile loading testing method, many investigators and practicing engineers have been concerned that the O-cell test would give inaccurate results, especially about the pile head settlement behavior. Therefore, a bidirectional load test using the Osterberg method and the conventional top-down load test were executed on 1.5-m diameter cast-in-place concrete piles at the same time and site. Strain gauges were placed on the piles. The two tests gave similar load transfer curves at various depth of piles. However, the top-down equivalent curve constructed from the bidirectional load test results predicted the pile head settlement under the pile design load to be approximately one half of that predicted by the conventional top-down load test. To improve the prediction accuracy of the top-down equivalent curve, a simple method that accounts for the pile compression was proposed. It was also shown that the strain gauge measurement data from the bidirectional load test could reproduce almost the same top-down curve.

RAPID LOAD TESTING OF STONE COLUMNS TO AID DESIGN OF FOUNDATIONS ON IMPROVED GROUND

2018 ◽  
Vol 5 (1) ◽  
Author(s):  
John Fahd Touma ◽  
Salah Sadek ◽  
Shadi Najjar
Keyword(s):  
Static Load ◽  
Ground Improvement ◽  
Compressive Force ◽  
Field Tests ◽  
Site Investigation ◽  
Shallow Foundations ◽  
Load Test ◽  
Stone Columns ◽  
Load Testing ◽  
Axial Compressive Force

Building Codes and best practice require load testing of embedded structural foundation elements to validate design and construction execution quality. This requirement is particularly challenging when associated with ground improvement schemes relying on granular reinforcing/stone columns. Stone columns present an economic solution for improving the bearing capacity of shallow foundations on soft soils. A novel impulse load test was developed and used to quantify the load-displacement response of shallow foundations supported on stone columns at a clay site. The device is referred to as the Rapid Plate Load Tester (RPLT) and is a modified version of the Axial Compressive Force Pulse test for deep foundations. In this paper, the comprehensive site investigation, stone columns construction, load testing procedure, and data analysis are described. Static and dynamic field tests were performed to target loads of 2000 kN and equivalent bearing pressures of 500kPa. The results obtained from the RPLT tests were used to derive equivalent static load settlement curves for footings on both the natural clay ground and improved ground and compared with the results obtained from the full-scale static load tests.

scholarly journals The influence of bottom-up anchors pre-tension optimization on the prediction of pit walls rockfall displacements

2021 ◽  
Vol 1 (3) ◽  
pp. 5-12
Author(s):  
Vikulov V. M. ◽  
Volkov M. N.
Keyword(s):  
Horizontal Displacement ◽  
Key Factors ◽  
Stability Calculation ◽  
Bottom Up ◽  
Optimal Value ◽  
Complex Calculation ◽  
Beam Bending ◽  
Anchor Structure ◽  
Urban Conditions ◽  
The Impact

Introduction. Currently in Russia, innovations in urban subsoil facilities construction are among the key factors of economic development. To improve the efficiency of holding a pit wall in restraint urban conditions and prevent soil loosening around the pit, it is proposed to optimize the pre-tension forces of the bottom-up anchors. It has been determined that the pre-tension forces of the active anchors create extra retention forces in the sliding wedge and, in some specified sense, reinforce the walled soil. Research methodology. When modeling the complex calculation of a pit wall, 4 main stages of the pit excavation and 3 stages of preliminary level tensions of anchor ties were preset. The numerical solution of the beam bending problem is the basic method of calculating the walling strength; the beam laying on the elastoplastic base and retained by the anchors as bonds. The bottom-up anchor structure is modeled in the operating environment of GeoWall software. The values of bottom-up anchors pre-tension are set following the ordinates of forces in the anchors, obtained from the walling stability calculation by the deterministic approach. Experimental research was carried out of the impact made by pit opening stages on the walling stress strained state. Results. Analysis and discussion. The efficiency of bottom-up anchors optimal pre-tension, according to the research results, is obtained by constructing the diagrams reflecting the correlation dependence between the anchors loading and the walling displacement. An obvious advantage of the software is the opportunity to calculate walling and retaining structures stage by stage ignoring their construction technologies. Experimental calculation in GeoWall has shown a high bearing capacity of the bottom-up anchor support. Summary. The nature of the obtained dependence between the anchor longitudinal forces and the pit walling horizontal displacement reflects the actual situation. Thus, for a quiet expectable value of horizontal displacement, it is required to correct the optimal value of pre-tension using the empiricalformula dependences.

REHABILITATION AND LOAD TESTING OF A BRIDGE

2016 ◽  
Vol 3 (1) ◽  
Author(s):  
Kawan G. Alani ◽  
Abdullah S. Ahmed
Keyword(s):  
Crude Oil ◽  
Structural Integrity ◽  
Load Test ◽  
Oil Fields ◽  
Load Testing ◽  
Test Results ◽  
Repair Work ◽  
Tigris River ◽  
The Impact ◽  
Good Agreement

Al-Fatha Bridge is constructed on Tigris River at Baiji town, about 220 km north of Baghdad. Beside its main purpose of connecting the main highway west of Tigris River with the Kirkuk city, its deck structure is purposely designed to carry pipes conveying crude oil from Kirkuk oil fields to Baiji refinery and to the oil exporting network of the country. During the war on Iraq in spring 2003, the bridge was subjected to an air strike. In addition to the damages caused by the impact and explosion of the munitions, the great fire of the crude oil erupted and lasted several days caused much heavier damages in different parts of the structure. The parts of the bridge damaged beyond repair, were replaced, while the parts which were found to have sufficient structural integrity were repaired. This paper addresses the repair and testing of the most affected span exposed to fire. The efficiency of the repair work had been evaluated by carrying out a load test on the above mentioned span. The deflection at different stages of loading were recorded at specified points and compared with theoretical results. Good agreement was obtained between the theoretical and measured deflections, which prove the adequacy of the repair work. This paper introduces briefly an assessment of damages of the bridge, the rehabilitation work, analysis and load test results.

Secular stagnation in the modern world

2018 ◽  
pp. 125-141 ◽  
Author(s):  
S. M. Drobyshevsky ◽  
P. V. Trunin ◽  
A. V. Bozhechkova
Keyword(s):  
Public Debt ◽  
Capital Accumulation ◽  
Technological Development ◽  
Japanese Economy ◽  
Modern World ◽  
Key Factors ◽  
Destruction Process ◽  
Secular Stagnation ◽  
The Impact

The paper studies the factors of secular stagnation. Key factors of long-term slowdown in economic growth include the slowdown of technological development, aging population, human capital accumulation limits, high public debt, creative destruction process violation etc. The authors analyze key theoretical aspects of long-term stagnation and study the impact of these factors on Japanies economy. The authors conclude that most of the factors have significant influence on the Japanese economy for recent decades, but they cannot explain all dynamics. For Russia, on the contrary, we do not see any grounds for considering the decline in the economy since 2013 as an episode of secular stagnation.

Case study: Prediction and field tests of railway noise and effects of a low-height noise barrier

2020 ◽  
Vol 68 (4) ◽  
pp. 303-314
Author(s):  
Yuna Park ◽  
Hyo-In Koh ◽  
University of Science and Technology, Transpo ◽  
University of Science and Technology, Transpo ◽  
University of Science and Technology, Transpo ◽  
...  
Keyword(s):  
High Speed ◽  
Field Tests ◽  
Residential Areas ◽  
Railway Systems ◽  
Railway Noise ◽  
Sound Levels ◽  
Noise Barrier ◽  
The Difference ◽  
Reduction Effect ◽  
The Impact

Railway noise is calculated to predict the impact of new or reconstructed railway tracks on nearby residential areas. The results are used to prepare adequate counter- measures, and the calculation results are directly related to the cost of the action plans. The calculated values were used to produce noise maps for each area of inter- est. The Schall 03 2012 is one of the most frequently used methods for the production of noise maps. The latest version was released in 2012 and uses various input para- meters associated with the latest rail vehicles and track systems in Germany. This version has not been sufficiently used in South Korea, and there is a lack of standard guidelines and a precise manual for Korean railway systems. Thus, it is not clear what input parameters will match specific local cases. This study investigates the modeling procedure for Korean railway systems and the differences between calcu- lated railway sound levels and measured values obtained using the Schall 03 2012 model. Depending on the location of sound receivers, the difference between the cal- culated and measured values was within approximately 4 dB for various train types. In the case of high-speed trains, the value was approximately 7 dB. A noise-reducing measure was also modeled. The noise reduction effect of a low-height noise barrier system was predicted and evaluated for operating railway sites within the frame- work of a national research project in Korea. The comparison of calculated and measured values showed differences within 2.5 dB.

Implication of Medical Treatment for Surgical Strategies in IBD

2019 ◽  
Vol 20 (13) ◽  
pp. 1363-1368
Author(s):  
Krisztina B. Gecse ◽  
Christianne J. Buskens
Keyword(s):  
Nutritional Status ◽  
Medical Treatment ◽  
Significant Proportion ◽  
Timing Of Surgery ◽  
Multidisciplinary Management ◽  
Key Factors ◽  
Surgical Strategies ◽  
Immunosuppressive Medications ◽  
Medical Paradigm ◽  
The Impact

Despite changing medical paradigm, still a significant proportion of patients with IBD require surgery. The patient's general condition, including nutritional status and the use of immunosuppressive medications is of great importance with regard to surgical complications, as well as the choice of optimal surgical strategy. The indication and the timing of surgery are key factors for the multidisciplinary management of IBD patients. The purpose of this review is to provide an overview on the impact of medical treatment on surgical strategies in IBD.

Examining Organizational, Cultural, and Individual-Level Factors Related to Workplace Safety and Health Awareness and Risks: A Systematic Review and Metric Analysis (Preprint)

2018 ◽  
Author(s):  
Edmund W. J. Lee ◽  
Han Zheng ◽  
Htet Htet Aung ◽  
Megha Rani Aroor ◽  
Chen Li ◽  
...  
Keyword(s):  
Systematic Review ◽  
Citation Count ◽  
Workplace Safety ◽  
Key Factors ◽  
Health Awareness ◽  
Individual Level ◽  
Metric Analysis ◽  
Safety And Health ◽  
The Impact ◽  
The Relationship

BACKGROUND Promoting safety and health awareness and mitigating risks are of paramount importance to companies in high-risk industries. Yet, there are very few studies that have synthesized findings from existing online workplace safety and health literature to identify what are the key factors that are related to (a) safety awareness, (b) safety risks, (c) health awareness, and (d) health risks. OBJECTIVE As one of the first systematic reviews in the area of workplace health and safety, this study aims to identify the factors related to safety and health awareness as well as risks, and systematically map these factors within three levels: organizational, cultural, and individual level. Also, this review aims to assess the impact of these workplace safety and health publications in both academic (e.g., academic databases, Mendeley, and PlumX) and non-academic settings (e.g., social media platform). METHODS The systematic review was conducted in line with procedures recommended by Preferred Reporting Items for Systematic Reviews and Meta-Analysis (PRISMA). First, Proquest, ScienceDirect and Scopus were identified as suitable databases for the systematic review. Second, after inputting search queries related to safety and health awareness and risks, the articles were evaluated based on a set of inclusion and exclusion criteria. Third, the factors identified in the included articles were coded systematically. Fourth, the research team assessed the impact of the articles through a combination of traditional and new metric analysis methods: citation count, Altmetric Attention Score, Mendeley readers count, usage count, and capture count. RESULTS Out of a total of 4,831 articles retrieved from the three databases, 51 articles were included in the final sample and were systematically coded. The results revealed six categories of organizational (management commitment, management support, organizational safety communication, safety management systems, physical work environment, and organizational environment), two cultural (interpersonal support and organizational culture), and four individual (perception, motivation, attitude and behavior) level factors that relate to safety and health awareness and risk. In terms of impact, the relationship between citation count and the various metrics measuring academic activity (e.g., Mendeley readers, usage count, and capture count) were mostly significant while the relationship between citation count and Altmetric Attention Score was non-significant. CONCLUSIONS This study provides a macro view of the current state of workplace safety and health research and gives scholars an indication on some of the key factors of safety and health awareness and risks. Researchers should also be cognizant that while their work may receive attention from the scholarly community, it is important to tailor their communication messages for the respective industries they are studying to maximize the receptivity and impact of their findings. CLINICALTRIAL N.A.

Poland

2017 ◽  
Author(s):  
Detlef Pollack ◽  
Gergely Rosta
Keyword(s):  
Catholic Church ◽  
Agricultural Production ◽  
The State ◽  
Religious Culture ◽  
Key Factors ◽  
Pope John Paul Ii ◽  
National Values ◽  
The Impact ◽  
State Socialist ◽  
The Church

The chapter on Poland focuses on two questions. Why, in contrast to all other state-socialist countries, did the church’s capacity for integration actually increase rather than decrease despite persecution and discrimination during the communist period? And why has this capacity also remained more or less constant (albeit to a lesser extent) in the period since the end of communist rule? The authors have identified four key factors in the remarkable resistance of the Polish Catholic Church during the period of communist persecution: the fusion of religious and national values, the specific conflict dynamics of the church’s struggle with the state, the structural conservatism of agricultural production in Poland, and the actions of Pope John Paul II. Explanations for the surprising stability of religiosity in Poland after 1990 point to the behaviour of the Church itself, to the internal pluralization of Catholicism, and to the impact of a homogeneous religious culture.

scholarly journals Alternative Control of Phragmidium rubi-idaei Infecting Two Rubus Species

Plants ◽  
2021 ◽  
Vol 10 (7) ◽  
pp. 1452
Author(s):  
Raluca-Maria Pârlici ◽  
Aurel Maxim ◽  
Stefania Mirela Mang ◽  
Ippolito Camele ◽  
Lucia Mihalescu ◽  
...  
Keyword(s):  
Organic Farming ◽  
Plant Pathogens ◽  
Field Experiments ◽  
Control Sample ◽  
Field Tests ◽  
In Vitro Tests ◽  
Rust Disease ◽  
Conidia Germination ◽  
The Impact

Organic berry plantations have been gaining popularity among farmers during recent years. Even so, farmers experience serious challenges in disease control management, which is a concern in organic farming. Phragmidiumrubi-idaei (DC) P. Karst is the pathogen responsible for blackberry and raspberry rust disease, one of the most present and active diseases in plantations. The antifungal certified products found on the organic farming market offer the opportunity for an efficient control strategy over plant pathogens in fruit shrub plantations. In this study, 5 natural based products—namely Altosan, Mimox, Canelys, Zitron, and Zeolite—were tested for their fungistatic effect over P. rubi-idaei. The experiments were carried out under laboratory conditions, performing observations over the impact of organic products, used at different concentration levels, on rust conidia germination. Moreover, field experiments were conducted in order to evaluate the efficiency of different treatments for rust control on raspberry (‘Polka’, ‘Veten’ and ‘Heritage’) and blackberry (‘Thorn Free’, ‘Chester’ and ‘Loch Ness’) varieties. Data analysis based on ANOVA tests showed significant differences between the tested variants and the control sample at p < 0.001. Furthermore, LSD test confirmed differences between all substances tested (p < 0.005). The natural products Canelys (formulated with cinnamon) and Zytron (based on citrus extract) have proven the highest inhibitory capacity for conidia germination during in vitro tests registering values of 80.42% and 78.34%, respectively. The same high inhibitory rates against rust pathogen were kept also in the field tests using the same two natural-based products mentioned earlier. In addition, outcomes from this study demonstrated that Zeolite is not recommended for raspberry or blackberry rust control.

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