scholarly journals Test study on thickness of soil layer at top of plate affecting uplift failure of the NT-CEPP

CONVERTER ◽  
2021 ◽  
pp. 258-268
Author(s):  
Yongmei Qian, Jiyuan Zhang, Ruozhu Wang, Yujie Jin
Keyword(s):  
Carrying Capacity ◽  
Soil Layer ◽  
Test Method ◽  
Small Scale ◽  
Undisturbed Soil ◽  
Soil Thickness ◽  
Test Study ◽  
Disturbed Soil ◽  
Adjacent Soil ◽  
Under Construction

This paper studies the influence of the thickness of the soil layer on the head of the plate on the carrying capacity of the new type concrete plates-expanded pile (NT-CEPP) under vertical tension, and innovatively uses the half-section pile test method to measure undisturbed soil and ANSYS is used for comparative analysis. Due to the small-scale test based on the half-section pile and disturbed soil, not only can the overall invalidation mechanism of the soil around the pile be seen more clearly, but the undisturbed soil can also be used to better ensure the stability of the soil. At the same time, in the test, depending on the real station under construction, the authenticity and economy of the test should be ensured. The results of test reveal that the invalidation behaviour of the on the top of plate of the NT-CEPP has little effect on the adjacent soil layer when the soil thickness of embedded slab is more than 3 times the length of the cantilever of the slab, and the characteristics of adjacent soil-layer had no influence on the carrying capacity of the plate.

scholarly journals Anti-Overturning Bearing Capacity of Rigid and Flexible Concrete Expanded Piles Subjected to Horizontal Load

2020 ◽  
Vol 2020 ◽  
pp. 1-14
Author(s):  
Yongmei Qian ◽  
Tingting Zhou ◽  
Wei Tian
Keyword(s):  
Bearing Capacity ◽  
Model Test ◽  
Simulation Analysis ◽  
Soil Mass ◽  
Test Method ◽  
Small Scale ◽  
Foundation Engineering ◽  
Undisturbed Soil ◽  
Vertical Loading ◽  
Custom Made

The concrete expanded pile is a new type of pile in the field of foundation engineering, which exhibits improved performance compared to the ordinary straight-hole pile. The expanded technique increases the bearing capacity of the pile, changes the overall load-bearing function of the pile body, and offers great development prospects. While the performance of the expanded pile has been studied for vertical loading, the performance of expanded pile when subjected to horizontal loading is not adequately understood. In order to investigate the performance of concrete expanded pile in resisting horizontal loads, particularly the anti-overturning capacity of rigid and flexible piles, this paper conducts an experimental model test and performs a numerical simulation. In the experiment, an innovative model test method is used for testing small-scale half-face pile with undisturbed soil. A custom-made soil extractor and a loading device are used to observe various stages of pile-soil interaction in real-time during the whole process of loading. Meanwhile, finite element simulation analysis is conducted on a pile model and the corresponding data on displacement, load, stress, and strain are collected to verify the experimental results. Based on the horizontal bearing capacity of rigid and flexible piles and the failure states of soil mass around the piles, two calculation models are proposed for the horizontal bearing capacity of rigid and flexible concrete expanded piles. The models will provide reliable theoretical guidance for the application of concrete expanded pile in engineering applications and for the research and development of pile foundation.

Experimental Study on Effect of Disc Form on Soil Failure State of Expanded Piles under Horizontal Force

2020 ◽  
Vol 980 ◽  
pp. 291-300
Author(s):  
Yong Mei Qian ◽  
Yu Chen Song ◽  
Yu Jie Jin ◽  
Thato Molomo Pius Moshoeshoe
Keyword(s):  
Test Method ◽  
Scale Model ◽  
Small Scale ◽  
Horizontal Force ◽  
Paper Test ◽  
Loading Test ◽  
Undisturbed Soil ◽  
Soil Failure ◽  
Failure State ◽  
Small Scale Model

In this paper, test method of half-section small-scale model with indoor undisturbed soil is used to study the effect of difference disc forms on bearing mechanism of concrete disc piles and soil failure state around piles under horizontal force. The model piles with different disc cross-section forms were designed under the condition of undisturbed soil, and loading test was carried out to analyze soil failure state around the pile. The results show that: under the action of horizontal force, soil around the pile is cracked along the midline; asymmetric bearing disc is more reasonable than symmetrical bearing disc. The minimum load difference between the disc end fillet and the disc tip fillet is less than 5%. The curved end of bearing disc has little effect on the horizontal bearing capacity of concrete expanded disc pile.

Hole-Cleaning Fibers Improve Cuttings-Carrying Capacity

2021 ◽  
Vol 73 (05) ◽  
pp. 63-64
Author(s):  
Chris Carpenter
Keyword(s):  
Flow Regime ◽  
Carrying Capacity ◽  
Rheological Model ◽  
Drilling Fluid ◽  
Test Method ◽  
Abu Dhabi ◽  
Rheological Parameters ◽  
Cleaning Efficiency ◽  
Hole Cleaning ◽  
Drilling Operations

This article, written by JPT Technology Editor Chris Carpenter, contains highlights of paper SPE 203147, “Investigating Hole-Cleaning Fibers’ Mechanism To Improve Cutting Carrying Capacity and Comparing Their Effectiveness With Common Polymeric Pills,” by Mohammad Saeed Karimi Rad, Mojtaba Kalhor Mohammadi, SPE, and Kourosh Tahmasbi Nowtarki, International Drilling Fluids, prepared for the 2020 Abu Dhabi International Petroleum Exhibition and Conference, Abu Dhabi, held virtually 9–12 November. The paper has not been peer reviewed. Hole cleaning in deviated wells is more challenging than in vertical wells because of the boycott effect or the eccentricity of the drillpipe. Poor hole cleaning can result in problems such as borehole packoff or excessive equivalent circulating density. The complete paper investigates a specialized fibrous material (Fiber 1) for hole-cleaning characteristics. The primary goal is to identify significant mechanisms of hole-cleaning fibers and their merits compared with polymeric high-viscosity pills. Hole-Cleaning Indices Based on a review of the literature, most effective parameters regarding hole cleaning in different well types were investigated. These parameters can be classified into the following five categories: - Well design (e.g., hole angle, drillpipe eccentricity, well trajectory) - Drilling-fluid properties (e.g., gel strength, mud weight) - Formation properties (e.g., lithology, cutting specific gravity, cuttings size and shape) - Hydraulic optimizations (e.g., flow regime, nozzle size, number of nozzles) - Drilling practices (e.g., drillpipe rotation speed, wellbore tortuosity, bit type, rate of penetration, pump rate) In this research, rheological parameters and parameters of the Herschel-Bulkley rheological model are considered to be optimization inputs to increase hole-cleaning efficiency of commonly used pills in drilling operations. The complete paper offers a detailed discussion of both the importance of flow regime and the role of the Herschel-Bulkley rheological model in reaching a better prognosis of drilling-fluid behavior at low shear rates. The properties of the fibrous hole-cleaning agent used in the complete paper are provided in Table 1. Test Method Two series of tests were performed. The medium of the first series is drilling water, with the goal of evaluating the efficiency of Fiber 1 in fresh pills. The second series of tests was per-formed with a simple polymeric mud as a medium common in drilling operations. Formulations and rheological properties of both test series are provided in Tables 4 and 5 of the complete paper, respectively.

scholarly journals SUSTAINABILITY OF PEDOBIONT MEADOW COMMUNITIES UNDER ANTHROPOGENIC LOAD

2020 ◽  
Author(s):  
T.A. Gordienko ◽  
◽  
R.A. Sukhodolskaya ◽  
D.N. Vavilov ◽  
Yu.A. Lukyanova ◽  
...  
Keyword(s):  
Soil Layer ◽  
Taxonomic Composition ◽  
Soil Mesofauna ◽  
High Soil Moisture ◽  
Small Width ◽  
Disturbed Soil ◽  
Disturbed Areas ◽  
Rapid Restoration ◽  
Litter Invertebrates ◽  
Large Soil

Studies of the soil mesofauna were carried out in Tanaev meadows of the «Nizhnyaya Kama» National Park in natural and disturbed areas. The abundance of pedobionts and herpetobionts in natural areas significantly exceeded the abundance in disturbed areas. However, the taxonomic composition and trophic structure were similar. In general, communities structure indexes in natural sites indicate a stable ecosystem of floodplain meadows. The observance of pipe laying technology during further restoration of disturbed areas, high soil moisture and a small width of the disturbed soil layer contribute to the preservation and rapid restoration of the structure and population of large soil and litter invertebrates of meadow phytocenosis.

The importance of aerodynamics for prosthetic limb design used by competitive cyclists with an amputation: An introduction

2014 ◽  
Vol 39 (3) ◽  
pp. 232-237 ◽  
Author(s):  
Bryce Dyer
Keyword(s):  
Field Test ◽  
Aerodynamic Drag ◽  
Field Tests ◽  
Field Testing ◽  
Test Method ◽  
Limb Amputation ◽  
Small Scale ◽  
Prosthetic Limb ◽  
Testing Method ◽  
Competitive Cyclists

Background/Objectives: This study introduces the importance of the aerodynamics to prosthetic limb design for athletes with either a lower-limb or upper-limb amputation. Study design: The study comprises two elements: 1) An initial experiment investigating the stability of outdoor velodrome-based field tests, and 2) An experiment evaluating the application of outdoor velodrome aerodynamic field tests to detect small-scale changes in aerodynamic drag respective of prosthetic limb componentry changes. Methods: An outdoor field-testing method is used to detect small and repeatable changes in the aerodynamic drag of an able-bodied cyclist. These changes were made at levels typical of alterations in prosthetic componentry. The field-based test method of assessment is used at a smaller level of resolution than previously reported. Results: With a carefully applied protocol, the field test method proved to be statistically stable. The results of the field test experiments demonstrate a noticeable change in overall athlete performance. Aerodynamic refinement of artificial limbs is worthwhile for athletes looking to maximise their competitive performance. Conclusion: A field-testing method illustrates the importance of the aerodynamic optimisation of prosthetic limb components. The field-testing protocol undertaken in this study gives an accessible and affordable means of doing so by prosthetists and sports engineers. Clinical relevance Using simple and accessible field-testing methods, this exploratory experiment demonstrates how small changes to riders’ equipment, consummate of the scale of a small change in prosthetics componentry, can affect the performance of an athlete. Prosthetists should consider such opportunities for performance enhancement when possible.

Comparison of Environmental Performance Expectations: Gasification Versus Mass-Burn WTE Facilities Currently Under Construction in North America

2012 ◽  
Author(s):  
Elizabeth A. Rice
Keyword(s):  
North America ◽  
Solid Waste ◽  
Environmental Performance ◽  
Fossil Fuels ◽  
Management Strategies ◽  
Waste To Energy ◽  
Small Scale ◽  
Emissions Modeling ◽  
Technology Applications ◽  
Under Construction

In recent years, factors including limited landfill capacity, increasing costs of fossil fuels, and increased pressure to actively recover value from waste in the form of materials and energy have encouraged municipalities throughout North America to advance waste management strategies that utilize waste-to-energy (WTE) technologies as an alternative to landfilling. Currently, utilization of alternative conversion technologies, including gasification, is limited to small-scale or pilot municipal solid waste (MSW) to energy facilities in North America. Though limited history of environmental performance when using MSW as a primary feedstock has delayed public acceptance of facility proposals, municipalities are now moving forward with alternative conversion technology applications. In Florida, two entities have received permits from the Department of Environmental Protection to proceed with construction of gasification facilities — Geoplasma, Inc. in St. Lucie County, and INEOS New Planet BioEnergy in Vero Beach. In Edmonton, Alberta, Canada, Enerkem GreenField Alberta Biofuels has received a permit from Alberta Environment to begin construction of a gasification facility that will produce bioethanol from post-recycled MSW. Since 1996, no new greenfield MSW-processing mass burn facility has been constructed in the U.S., though facilities in Hillsborough County, FL; Lee County, FL; and Olmstead County, MN have undergone expansions, and in Honolulu, FL, a 900 TPD unit is currently under construction. In recent years, two municipalities have received permits to proceed with construction of mass burn WTE facilities and have made significant progress toward implementation: The municipalities of Durham and York, Ontario, Canada and The Solid Waste Authority of Palm Beach County, Florida. This paper will provide a direct comparison of the expected environmental performance of the recently permitted gasification facilities to the expected environmental performance of the recently permitted mass burn WTE facilities, as established by permit applications and emissions modeling studies. Comparison of emissions of particulate matter, sulfur dioxide, nitrogen oxides, carbon monoxide, volatile organic compounds, and hydrogen chloride will be performed on the basis of one ton of feedstock processed. Emission of these pollutants at the recently permitted facilities discussed above will be contrasted with emissions experienced at currently operating WTE facilities within North America.

scholarly journals New Approach for Understanding the Oxidation Stability of Neopolyol Ester Lubricants Using a Small-Scale Oxidation Test Method

ACS Omega ◽  
2018 ◽  
Vol 3 (9) ◽  
pp. 10449-10459 ◽  
Author(s):  
Sandrine Duong ◽  
Nora Lamharess-Chlaft ◽  
Mickaël Sicard ◽  
Bruno Raepsaet ◽  
Maria Elena Galvez ◽  
...  
Keyword(s):  
Oxidation Stability ◽  
Test Method ◽  
Small Scale ◽  
New Approach ◽  
Oxidation Test
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