Arch-Supported Reticulated Shell Structures and Their Static Mechanical Behaviour

2002 ◽  
Vol 17 (4) ◽  
pp. 263-269 ◽  
Author(s):  
Yuan-Qi Li ◽  
Zu-Yan Shen
Keyword(s):  
Mechanical Behaviour ◽  
Single Layer ◽  
Structural Features ◽  
Shell Structures ◽  
Hybrid Structures ◽  
Structural System ◽  
Imperfection Sensitivity ◽  
Geometrical Imperfection ◽  
Static Mechanical ◽  
Arch Structures

Based on the structural features of reticulated shells, arch structures, etc., arch-supported reticulated shell structures have been developed as a new large-span space structural system. In the paper, the acceptability of this hybrid structural system and the reasonable combination of arch structures and reticulated shells with different Gaussian curvatures are discussed. Several ideas on using arch-supported reticulated shell structures to form openable structures are also mentioned. Compared to single-layer reticulated shells, the mechanical behaviour of the hybrid structures, especially the influence of initial geometrical imperfection, was investigated through nonlinear analysis and experimental research on three typical models. Analysis indicates that hybrid structures can efficiently decrease the geometrical imperfection sensitivity and improve their integral mechanical behaviour, which proves that this type of hybrid structures can be used widely.

An Investigation on Bending Capacity of Support Stiffness Wall-Slab Structural System by Using Single Layer and Double Layer of Rebar for Residential Project

2012 ◽  
Vol 446-449 ◽  
pp. 3670-3673
Author(s):  
Hooi Min Yee ◽  
Siti Isma Hani Ismail
Keyword(s):  
Double Layer ◽  
Concrete Strength ◽  
Single Layer ◽  
Concrete Cover ◽  
Structural System ◽  
Average Percentage ◽  
High Rise ◽  
Percentage Difference ◽  
Average Percentage Difference ◽  
Bending Capacity

Wall-slab structural system is a system suitable for use in the field of high-rise building where the main load resisting system is in the form rigidly connected wall slab member. Concrete vertical walls may serve both architecturally partitions and structurally to carry gravity and lateral loading. Moment transfer of joint is an important aspect for proper structurally functioning of wall-slab system. Hence, the main aim of this study is to investigate experimentally the effect of reinforcement details in the wall on bending capacity for support stiffness in wall-slab system for residential project in Malaysia. A total of six wall specimens were tested based on the specification given by the project contractor. Three of this specimens consisted single layer of rebar while another three specimen consisted of double layer of rebar. The size of the wall-slab’s specimens is 1000mm in length (L), 1080mm in width (W), 1000mm in height (H) and 80mm in thickness (T). The average concrete strength was 23.49MPa with Grade 30N/mm2 and the average yield strength of R5 bar was 817MPa. The predicted bending capacity at failure is in the range from 5.36kNm to 7.12kNm, depending on actual concrete cover. The bending capacity at failure for single layered of rebar in wall for specimen 1, 2 and 3 were found to be 3.59kNm, 3.81kNm and 3.15kNm, respectively. The bending capacity at failure for double layered of rebar in wall for specimen 1, 2 and 3 were 5.50kNm, 6.31kNm and 7.00kNm, respectively. The average percentage difference in stiffness of double layered of rebar in wall based on load-deflection curve obtained is in the range from 116.17% to 289.88% higher than single layered of rebar in wall. Based on the experimental results, specimens consisted of double layered of rebar in wall is found to provide higher bending capacity to the joint of wall-slab structural system in the range from 56.25% to 98.86% compared with single layered of rebar in wall.

Link prediction via layer relevance of multiplex networks

2017 ◽  
Vol 28 (08) ◽  
pp. 1750101 ◽  
Author(s):  
Yabing Yao ◽  
Ruisheng Zhang ◽  
Fan Yang ◽  
Yongna Yuan ◽  
Qingshuang Sun ◽  
...  
Keyword(s):  
Structural Properties ◽  
Link Prediction ◽  
Structural Information ◽  
Similarity Index ◽  
Single Layer ◽  
Structural Features ◽  
Prediction Performance ◽  
Multiplex Networks ◽  
Multiplex Network ◽  
Node Similarity

In complex networks, the existing link prediction methods primarily focus on the internal structural information derived from single-layer networks. However, the role of interlayer information is hardly recognized in multiplex networks, which provide more diverse structural features than single-layer networks. Actually, the structural properties and functions of one layer can affect that of other layers in multiplex networks. In this paper, the effect of interlayer structural properties on the link prediction performance is investigated in multiplex networks. By utilizing the intralayer and interlayer information, we propose a novel “Node Similarity Index” based on “Layer Relevance” (NSILR) of multiplex network for link prediction. The performance of NSILR index is validated on each layer of seven multiplex networks in real-world systems. Experimental results show that the NSILR index can significantly improve the prediction performance compared with the traditional methods, which only consider the intralayer information. Furthermore, the more relevant the layers are, the higher the performance is enhanced.

Cobalt Based Alloys for Dental Applications

2013 ◽  
Vol 583 ◽  
pp. 175-178 ◽  
Author(s):  
Brandusa Ghiban ◽  
Cristina Maria Borţun ◽  
Alexandru Ghiban ◽  
Nicolae Ghiban
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
Mechanical Behaviour ◽  
Structural Features ◽  
Molybdenum Content ◽  
Cobalt Alloys ◽  
Mo Content ◽  
Dental Applications ◽  
Scanning Electron

The present paper put in evidence the mechanical behaviour of some commercial dental cobalt alloys, after own classification. The experimental cobalt alloys were classified in according either with molybdenum content, or with Cr+Mo content. A hierarcy of the alloys was finally made. The fractographic surfaces were investigate both by stereomacroscopy and scanning electron microscopy, putting in evidence the main structural features.

Grid patterns optimization for single-layer latticed domes

2020 ◽  
pp. 136943322095681
Author(s):  
Masaki Teranishi ◽  
Koichiro Ishikawa
Keyword(s):  
Mechanical Properties ◽  
Single Layer ◽  
Objective Functions ◽  
Imperfection Sensitivity ◽  
Grid Pattern ◽  
Geometric Imperfection ◽  
Design Variables ◽  
Geometrical Constraints ◽  
Nodal Coordinates ◽  
Superior Mechanical Properties

In previous studies on optimized single-layer latticed domes, the inner space and external shape of the optimized dome is different from those of the initial dome. This difference may result in loss of structural functionality and aesthetics intended by the designers, making it difficult to separately evaluate the mechanical properties of the grid patterns and shape of the surface. In this study, 64 types of single-layer latticed domes having different geometric properties are optimized to obtain mechanically effective grid patterns. Six types of objective functions are employed. The nodal coordinates of the domes serve as the design variables under geometrical constraints, where the nodes of the domes can be shifted on the surface area. The geometric and mechanical properties of the optimized grid patterns are evaluated quantitatively against the objective functions. Moreover, interactions between the geometric and mechanical properties are investigated. The results show that the optimized grid pattern has superior mechanical properties and geometric imperfection sensitivity. This optimization scheme can be applied for designing mechanically effective grid patterns for single-layer latticed domes.

Isogeometric analysis of laminated smart shell structures covered with piezoelectric sensors and actuators using degenerated shell formulation

2019 ◽  
Vol 30 (13) ◽  
pp. 1913-1931 ◽  
Author(s):  
Sajjad Nikoei ◽  
Behrooz Hassani
Keyword(s):  
Single Layer ◽  
Laminated Composite ◽  
Piezoelectric Sensor ◽  
Basis Functions ◽  
Shell Structures ◽  
Free Form ◽  
Control Analysis ◽  
Sensors And Actuators ◽  
Spline Basis ◽  
Shell Formulation

An isogeometric approach to the analysis of laminated composite smart shell structures based on the degenerated formulation and Mindlin–Reissner assumptions using non-uniform rational B-spline basis functions is the subject of this article. To model the laminated orthotropic smart free-form shells, the equivalent single layer theory is adopted, and an accurate approach to construct the local basis systems is used. To consider the electric potential in the piezoelectric layers, a sub-layer approach is employed that assumes linear variation over the thickness of the sub-layer. To investigate the performance of the approach, static, free vibration, and static control analysis of laminated composite shells covered with piezoelectric sensor and actuator layers with different degrees of basis functions is performed. Also, the effect of mechanical loading, various input voltages, and different boundary conditions on the static response and natural frequencies have been investigated. Several numerical examples are presented to demonstrate the efficiency and accuracy of the approach and validated with the existing results from the literature.

Microstructural Properties of Common Yew and Norway Spruce Determined with Silviscan

IAWA Journal ◽  
2009 ◽  
Vol 30 (2) ◽  
pp. 165-178 ◽  
Author(s):  
Daniel Keunecke ◽  
Robert Evans ◽  
Peter Niemz
Keyword(s):  
Mechanical Behaviour ◽  
Mechanical Response ◽  
Elastic Anisotropy ◽  
Longitudinal Direction ◽  
Structural Features ◽  
Structure Property ◽  
Tangential Plane ◽  
Cross Sectional ◽  
X Ray ◽  
The Difference

Yew wood holds a special position within the softwoods with regard to its exceptional elasto-mechanical behaviour. Despite a relatively high density, it is highly elastic in the longitudinal direction (the modulus of elasticity is low and the stretch to break high). In the radial-tangential plane, its elastic anisotropy is clearly less pronounced compared to other softwoods such as spruce. Knowledge of the anatomical organisation of yew wood is an indispensable precondition for the correct interpretation of this conspicuous mechanical behaviour. The aim of this study, therefore, was to interpret the difference in elasto-mechanical behaviour of yew and spruce (as a reference) through their relative microstructures as measured by SilviScan, a technology based on X-ray densitometry, X-ray diffractometry and optical microscopy. This system is able to measure a variety of structural features in a wood sample. The results reveal that the elasto-mechanical response of yew is primarily due to large microfibril angles and a more homogeneous cross-sectional tissue composition (regarding tracheid dimensions and density distribution) compared to spruce. With respect to structure-property relationships, it was concluded that yew wood combines properties of normal and compression wood and therefore takes an intermediate position between them.

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