Influence of Snow Load Distribution on the Stability of Single-layer Reticulated Shells

Based on the heating load experiment adopting on-off time and area measuring method of typical heat users located in different places of different buildings in Shijiazhuang, the heating loads of the heat users which are summarized as two typical heat using modes are studied in this paper and the heating loads in the whole winter heating season of the building is estimated. The results shows that with the user’s heat adopting ratio in these two modes increases, the corresponding heating load is lower, the heating load distribution curve gets smoothly in the whole heating period and the peak value of the system heating loads reduces. This regularity of heating load distribution is beneficial for enhancing the stability of heating system and the thermal efficiency of the heat source.

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Electrolysis soy protein isolate-based oleogels prepared with an emulsion-templated approach

International Journal of Food Engineering ◽

10.1515/ijfe-2021-0076 ◽

2021 ◽

Vol 0 (0) ◽

Author(s):

Dianyu Yu ◽

Yan Chen ◽

Xing Chen ◽

Yunyan Huang ◽

Liqi Wang ◽

...

Keyword(s):

Soy Protein ◽

Xanthan Gum ◽

Binding Capacity ◽

Soy Protein Isolate ◽

Single Layer ◽

Protein Isolate ◽

Regulatory Limits ◽

Order Of Magnitude ◽

The Stability ◽

Oil Binding

Abstract This research focuses on the use of protein-polyphenol complex and protein-polyphenol: polysaccharide complexes to prepare oleogels through an emulsion-templated approach. Electrolysis soy protein isolate (ESPI) could be effectively adsorbed on the surface of a single-layer emulsion to increase the particle size. The order of the negative charges of the emulsion after adding polysaccharides was xanthan gum (XG)> pectin> carboxymethyl cellulose (CMC). Rheological behavior showed that the stability of the double-layer emulsions increased, and the viscoelasticity increased around one order of magnitude with the addition of polysaccharides. The oil binding capacity (OBC) of the oleogel prepared by adding polysaccharides increased to more than 97%. The peroxide value (PV) and anisidine value (AV) of XG oleogel were the minimum values in all samples. The AV and POV were within the regulatory limits of China after storage for 21 days. This provides a reference to design of ESPI-based oleogel for different applications.

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Analysis of Nonlinear Buckling of a Long-Span Elliptic Paraboloid Suspended Dome Structure

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.639-640.191 ◽

2013 ◽

Vol 639-640 ◽

pp. 191-197 ◽

Cited By ~ 3

Author(s):

Zheng Rong Jiang ◽

Kai Rong Shi ◽

Xiao Nan Gao ◽

Qing Jun Chen

Keyword(s):

Single Layer ◽

Buckling Mode ◽

Nonlinear Buckling ◽

Elliptic Paraboloid ◽

Geometric Imperfection ◽

Long Span ◽

Initial Geometric Imperfection ◽

Dome Structure ◽

Unsymmetrical Loading ◽

The Stability

The suspended dome structure, which is a new kind of hybrid spatial one composed of the upper single layer latticed shell and the lower cable-strut system, generally has smaller rise-to-span ratio, thus the overall stability is one of the key factors to the design of the structure. The nonlinear buckling behavior of an elliptic paraboloid suspended dome structure of span 110m80m is investigated by introducing geometric nonlinearity, initial geometric imperfection, material elastic-plasticity and half-span distribution of live loads. The study shows that the coefficient of stable bearing capacity usually is not minimal when the initial geometric imperfection configuration is taken as the first order buckling mode. The unsymmetrical loading distribution and the material nonlinearity might have significant effects on the coefficient. The structure is sensitive to the changes of initial geometric imperfection, and the consistent mode imperfection method is not fully applicable to the stability analysis of suspended dome structure.

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The stability of boundary-layer flow over single-and multi-layer viscoelastic walls

Journal of Fluid Mechanics ◽

10.1017/s0022112088002745 ◽

1988 ◽

Vol 196 ◽

pp. 359-408 ◽

Cited By ~ 48

Author(s):

K. S. Yeo

Keyword(s):

Boundary Layer ◽

Boundary Layer Flow ◽

Single Layer ◽

Viscous Sublayer ◽

Rigid Base ◽

Theoretical Treatment ◽

Dynamical Condition ◽

Compliant Walls ◽

Layer Flow ◽

The Stability

In this paper, we are concerned with the linear stability of zero pressure-gradient laminar boundary-layer flow over compliant walls which are composed of one or more layers of isotropic viscoelastic materials and backed by a rigid base. Wall compliance supports a whole host of new instabilities in addition to the Tollmien-Schlichting mode of instability, which originally exists even when the wall is rigid. The perturbations in the flow and the compliant wall are coupled at their common interface through the kinematic condition of velocity continuity and the dynamical condition of stress continuity. The disturbance modes in the flow are governed by the Orr-Sommerfeld equation using the locally-parallel flow assumption, and the response of the compliant layers is described using a displacement-stress formalism. The theoretical treatment provides a unified formulation of the stability eigenvalue problem that is applicable to compliant walls having any finite number of uniform layers; inclusive of viscous sublayer. The formulation is well suited to systematic numerical implementation. Results for single- and multi-layer walls are presented. Analyses of the eigenfunctions give an insight into some of the physics involved. Multi-layering gives a measure of control over the stability characteristics of compliant walls not available to single-layer walls. The present study provides evidence which suggests that substantial suppression of disturbance growth may be possible for suitably tailored compliant walls.

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Wind tunnel tests and analysis of snow load distribution on three different large size stadium roofs

Cold Regions Science and Technology ◽

10.1016/j.coldregions.2019.02.002 ◽

2019 ◽

Vol 160 ◽

pp. 163-175 ◽

Cited By ~ 2

Author(s):

Andrzej Flaga ◽

Łukasz Flaga

Keyword(s):

Wind Tunnel ◽

Load Distribution ◽

Wind Tunnel Tests ◽

Snow Load ◽

Large Size

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The Stability of Temporary Restorations Fabricated on a Healing Cap for Immediate Loading: An In Vitro Study

Applied Sciences ◽

10.3390/app8112261 ◽

2018 ◽

Vol 8 (11) ◽

pp. 2261

Author(s):

Sangho Jun ◽

Hyonseok Jang ◽

Enji Cheon ◽

MinJu Kim ◽

Sungwon Ju ◽

...

Keyword(s):

Compressive Strength ◽

Load Distribution ◽

In Vitro Study ◽

Bite Force ◽

Immediate Loading ◽

Pull Out ◽

The Stability ◽

Implant Treatment ◽

Pull Out Strength

The aim of this study was to analyze the load distribution of interim restorations using healing cap during immediate loading implant treatment in vitro. A total of 29 models with interim restorations which were fabricated with healing cap were selected. The pull-out strength was measured with a used healing cap and new healing cap. The compressive strength and sinking distance were also measured. The pull-out strength of interim restoration showed lower value (max. 29.8 N) compared to the natural bite force. The sinking amounts were larger than normal tooth sinking. The sinking amounts of interim restorations fabricated on a healing cap were roughly 3 times (0.3–0.5 mm under 450 N) those of normal teeth. The interim restoration on plastic healing cap would be useful for immediate loading implant treatment.

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Ultimate Load Analysis of Single-Layer Lattice Shells under Temperature Action

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.170-173.2592 ◽

2012 ◽

Vol 170-173 ◽

pp. 2592-2596

Author(s):

Shu Tang Liu ◽

Qi Liang Long ◽

Long Wang

Keyword(s):

Temperature Change ◽

Shell Structure ◽

Single Layer ◽

Cold Season ◽

Change Impact ◽

The Stability ◽

Reticulated Shell Structure ◽

Temperature Action ◽

Important Measurement ◽

Design Construction

Stability is an important measurement index of reticulated shell structure to security and reliability. Considering the temperature change, using structural buckling analysis in ANSYS, the stability of reticulated shell structure was invested. Analysis shows that stability of reticulated shell structure affected by temperature change impact; as the temperature goes down, the safety factor (stability coefficient) continually decrease. The conclusion showed that: 1) reticulated shell construction is suitable in summer; 2) Insulated curing of shell should be paid attention in cold season, and which will be useful on design, construction and use of structure.

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Experimental Research on the Stability of Spatial Lattice Shell

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.204-208.3048 ◽

2012 ◽

Vol 204-208 ◽

pp. 3048-3051

Author(s):

Gan Tang ◽

Wei Wei Li ◽

Lin Feng Yin ◽

Xiao Ming Guo

Keyword(s):

Control System ◽

Data Acquisition ◽

Experimental Research ◽

Single Layer ◽

Data Acquisition System ◽

Stability Behavior ◽

Initial Imperfections ◽

Spatial Lattice ◽

The Stability ◽

Lattice Shell

In the interest of an understanding to the imperfection stability behavior, a model of single layer spherical lattice shell was designed. The size and the pattern of initial imperfections were entirely measured. Automatic harmony loading control system and data acquisition system was used. The experiment plan, method and results have provided reference significance for the study on the stability of spatial lattice shell. The experimental results and the results of measured imperfections method were compared and analysed in detail. It is verified that measured imperfections method can accurately take into account of the effect of initial imperfections and it can be used for the supplementary checking computations of some important finished structures.

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Development of a Snow Load Alert System, “YukioroSignal” for Aiding Roof Snow Removal Decisions in Snowy Areas in Japan

Journal of Disaster Research ◽

10.20965/jdr.2020.p0688 ◽

2020 ◽

Vol 15 (6) ◽

pp. 688-697

Author(s):

Hiroyuki Hirashima ◽

Tsutomu Iyobe ◽

Katsuhisa Kawashima ◽

Hiroaki Sano ◽

◽

...

Keyword(s):

Snow Depth ◽

Load Distribution ◽

Snow Water Equivalent ◽

Snow Accumulation ◽

Risk Level ◽

Residential Areas ◽

Alert System ◽

Snow Removal ◽

Snow Load ◽

Snow Water

This study developed a snow load alert system, known as the “YukioroSignal”; this system aims to provide a widespread area for assessing snow load distribution and the information necessary for aiding house roof snow removal decisions in snowy areas of Japan. The system was released in January 2018 in Niigata Prefecture, Japan, and later, it was expanded to Yamagata and Toyama prefectures in January 2019. The YukioroSignal contains two elements: the “Quasi-Real-Time Snow Depth Monitoring System,” which collects snow depth data, and the numerical model known as SNOWPACK, which can calculate the snow water equivalent (SWE). The snow load per unit area is estimated to be equivalent to SWE. Based on the house damage risk level, snow load distribution was indicated by colors following the ISO 22324. The system can also calculate post-snow removal snow loads. The calculated snow load was validated by using the data collected through snow pillows. The simulated snow load had a root mean square error (RMSE) of 21.3%, which was relative to the observed snow load. With regard to residential areas during the snow accumulation period, the RMSE was 13.2%. YukioroSignal received more than 56,000 pageviews in the snowheavy 2018 period and 26,000 pageviews in the less snow-heavy 2019 period.

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