scholarly journals REVIEW OF ANALYTICAL MODELS FOR ESTIMATING THE BEARING CAPACITY OF WOODEN BEAMS REINFORCED WITH FIBER COMPOSITES

2021 ◽  
Vol 177 (27) ◽  
pp. 76-82
Author(s):  
Damian Jończyk ◽  
◽  
Marlena Rajczyk ◽  
Keyword(s):  
Bearing Capacity ◽  
Fiber Composites ◽  
Analytical Models

scholarly journals Analytical modelling of a three-layer wall system of strengthening for large-panel slab buildings by means of bonded anchors

2018 ◽  
Vol 174 ◽  
pp. 04012
Author(s):  
Jerzy K. Szlendak ◽  
Agnieszka Jablonska-Krysiewicz ◽  
Dariusz Tomaszewicz
Keyword(s):  
Bearing Capacity ◽  
Analytical Models ◽  
Simultaneous Action ◽  
Strength Parameters ◽  
Load Bearing Capacity ◽  
Load Bearing ◽  
Pull Out ◽  
Large Panel ◽  
Wall System ◽  
New System

The goal of the article is to elaboration analytical models describing a new system of reinforcing three-layer walls of large-panel buildings with bonded anchors. The use of this type of fasteners that bond the façade texture layer to the structural slab is necessary due to the low durability of previously used suspension elements. Various bonded anchorage systems were considered. The new anchorage systems were designed as two-anchors systems (horizontal anchor and diagonal anchors) and three-anchors systems (horizontal anchor and two diagonal anchors). The inclinations of these anchors are in the range of 30°-60° in relation to the surface of the element. For the above types of reinforcements, analytical models have been developed that take into account the change of strength parameters of the resin and steel from which the anchors were made, the interaction of materials resin-steel and resin-concrete and the effect of the simultaneous action of pull-out and shearing forces. Moreover, was assumed the simultaneous destruction of fasteners two- and three-anchors. The elaborated analytical models will be used to determine the load-bearing capacity of the new connector system, which will allow the elaboration of guidelines for strengthening three-layer walls of largepanel slab buildings.

Bearing capacity of spread footings on aggregate pier–reinforced clay: updates and stress concentration

2020 ◽  
Vol 57 (5) ◽  
pp. 717-727 ◽  
Author(s):  
Taeho Bong ◽  
Armin W. Stuedlein ◽  
John Martin ◽  
Byoung-Il Kim
Keyword(s):  
Stress Concentration ◽  
Bearing Capacity ◽  
Cross Validation ◽  
Slenderness Ratio ◽  
Ground Improvement ◽  
Analytical Models ◽  
Loading Test ◽  
Replacement Ratio ◽  
Area Replacement Ratio ◽  
Reinforced Clay

Aggregate piers represent an economical ground improvement technique used to increase bearing capacity and reduce settlements of weak soils. Several approaches have been developed to estimate the bearing capacity of aggregate pier–reinforced clay, but these models exhibit large prediction bias and uncertainty. This study uses newly developed footing loading test data to investigate the relationship between the bearing capacity and the area replacement and slenderness ratios. The bearing capacity of a single aggregate pier, whether isolated or in groups, below a loaded footing increases as the area replacement ratio decreases due to increase in extent of confined soil surrounding the pier. The length and diameter of an aggregate pier is also shown to result in significantly increased bearing capacity, an effect that diminishes with increasing slenderness. New modifications are proposed to existing simplified and cavity expansion models to account for the effect of confinement, area replacement ratio, and slenderness ratio using a leave-one-out cross-validation technique. The cross-validation analysis resulted in robust bearing capacity models that are more accurate than existing analytical models. Additionally, the stress concentration ratio for shallow foundations supported by aggregate pier–reinforced plastic soils at failure was estimated and compared with the available data, indicating its sensitivity to design variables and showing that this critical design parameter may be predicted using the updated models.

Shear in Flexure of Fiber Composites with Different End Supports

2003 ◽  
Vol 82 (4) ◽  
pp. 262-266 ◽  
Author(s):  
K.A. Eckrote ◽  
C.J. Burstone ◽  
M.A. Freilich ◽  
G.E. Messer ◽  
A.J. Goldberg
Keyword(s):  
Flexural Rigidity ◽  
Fiber Composites ◽  
Experimental Results ◽  
Analytical Models ◽  
Beam Deflection ◽  
Fiber Reinforced Composite ◽  
Simply Supported ◽  
Aspect Ratios ◽  
Reinforced Composite ◽  
D Values

The integrity of fiber-reinforced composite (FRC) prostheses is dependent, in part, on flexural rigidity. The object of this study was to determine if the flexure behavior of uniform FRC beams with restrained or simply supported ends and various length/depth (L/d) aspect ratios could be more accurately modeled by correcting for shear. Experimental results were compared with three analytical models. All models were accurate at high L/d ratios, but the shear-corrected model was accurate to the lowest, more clinically relevant, L/d values. In this range, more than 40% of the beam deflection was due to shear.

Flexural Performance Experimental Study on the Recycled Concrete Beams Under the Influence of Various Factors

2014 ◽  
Vol 926-930 ◽  
pp. 571-575
Author(s):  
Bin Bin Li ◽  
She Liang Wang ◽  
Juan Li Zhao
Keyword(s):  
Experimental Study ◽  
Shear Strength ◽  
Bearing Capacity ◽  
Concrete Beams ◽  
Fiber Composites ◽  
Recycled Concrete ◽  
Experimental Results ◽  
Replacement Ratio ◽  
Flexural Performance ◽  
Aggregate Content

Considering the replacement ratio, reinforcement ratio, baked brick aggregate content, SF, superplasticizer content and multiphase fiber composites content, the 13 RAC beams were tested to study the 5 kinds of effects on the bearing capacity and deformation performance. Based on the experimental results, the following conclusions are drawn: the formulas for the bending bearing capacity and shear strength of recycled concrete beams were recommended, and compared with the experiment results, the reliability of the formulas was verified.

scholarly journals INVESTIGATION OF SHALLOW FOUNDATION SOIL BEARING CAPACITY AND SETTLEMENT CHARACTERISTICS OF MINNA CITY CENTRE DEVELOPMENT SITE USING PLAXIS 2D SOFTWARE AND EMPIRICAL FORMULATIONS

2017 ◽  
Vol 36 (3) ◽  
pp. 663-670
Author(s):  
AB Salahudeen ◽  
JA Sadeeq
Keyword(s):  
Soil Properties ◽  
Bearing Capacity ◽  
Average Energy ◽  
Shallow Foundations ◽  
Shallow Foundation ◽  
Analytical Models ◽  
City Centre ◽  
Foundation Soil ◽  
Development Site ◽  
Allowable Bearing Pressure

This study investigated the soil bearing capacity and foundation settlement characteristics of Minna City Centre development site using standard penetration test (SPT) data obtained from10 SPT boreholes at 0.6, 2.1 and 3.6 m depths to correlate soil properties. Evaluation of foundation bearing capacity and settlement characteristics for geotechnical preliminary design of foundations was carried out using some conventional empirical/analytical models and numerical modelling. The aim was to investigate and determine the geotechnical parameters required for adequate design of Physical structures of the proposed Minna City Centre, at Minna the capital of Niger state. The SPT N-values were corrected to the standard average energy of 60% (N60) before the soil properties were evaluated. Using the corrected N-values, allowable bearing pressure and elastic settlement of shallow foundations were predicted at 50 kN/m2 applied foundation pressure. The numerical analysis results using Plaxis 2D, a finite element code, shows the analytical/empirical methods of estimating the allowable bearing pressure and settlements of shallow foundations that provided acceptable results. Results obtained show that an average bearing capacity value of 100 – 250 kN/m2 can be used for shallow foundations with embedment of 0.6 to 3.6 m on the site.  http://dx.doi.org/10.4314/njt.v36i3.1

scholarly journals The Behavior of Strip Footing Resting on Soil Strengthened with Geogrid

2021 ◽  
Vol 0 (0) ◽  
Author(s):  
Duaa Al-Jeznawi ◽  
Adel A. Al-Azzawi
Keyword(s):  
Finite Elements ◽  
Bearing Capacity ◽  
Soil Improvement ◽  
Strip Footing ◽  
Analytical Models ◽  
Number Of Layers ◽  
Settlement Behavior ◽  
Load Carrying ◽  
Low Load ◽  
The World

Abstract The soil in Iraq has a low load carrying or bearing capacity and high deflections or settlement because of the applied loads. The use of strip footing as a foundation to support different kinds of heavy structures has become necessary nowadays through solving such problems by using geogrid. This soil improvement technique is widely used all over the world. In this paper, the bearing capacity and settlements were calculated using finite elements and analytical models for strip footing resting on different kinds of soil. The study parameters are footing rigidity, the number of layers in a geogrid, the dimension of geogrid, and spacing of geogrid layers. According to the findings, the geogrid improved the bearing ability of the footing and reduced settlement. The optimum geogrid dimension was three times the footing width, and three geogrid layers were optimum. The changing in footing rigidity also affects the stress and settlement behavior.

MODELING OF PARAMETERS OF BEARING CAPACITY OF THE REINFORCED ROAD SURFACE

2017 ◽  
Vol 184 (2) ◽  
pp. 175-183
Author(s):  
Andrzej SUROWIECKI ◽  
Piotr SASKA ◽  
Artur DUCHACZEK
Keyword(s):  
Bearing Capacity ◽  
Road Construction ◽  
Reinforced Soil ◽  
Road Surface ◽  
Physical Models ◽  
Analytical Models ◽  
Granular Soil ◽  
Surface Foundation ◽  
The Subject ◽  
Theoretical Mechanics

The subject of the article is to assess the effectiveness of using the reinforcement system in road construction (surface, foundation, subgrade), treated as the multilayer system of granular soil. In the first part of the paper the authors use analytical models of friable layers of soil with horizontal inserts in order to evaluate the bearing capacity of the reinforced road surface, basing on results of the experimental research realized on physical models on a laboratory scale. The second part takes the form of a diagnosis as regards the possibility of quantitative estimations of the bearing capacity, and provides the bases of procedures aiming at the assessment of the bearing capacity of the reinforced soil by means of advanced methods and approaches in geotechnical engineering and theoretical mechanics.

Strengthening Proposals for the Trigonio Tower at the City Walls of Thessaloniki

2010 ◽  
Vol 133-134 ◽  
pp. 879-884 ◽  
Author(s):  
Vasiliki Delizisi ◽  
Matina Axiotidou ◽  
Ioannis N. Doudoumis ◽  
Christos Ignatakis
Keyword(s):  
Bearing Capacity ◽  
Analytical Models ◽  
Masonry Building ◽  
Seismic Excitations ◽  
Unesco World Heritage ◽  
Linear Elastic ◽  
15Th Century ◽  
City Walls ◽  
Not At Risk ◽  
The City

The Trigonio tower, constructed in the 15th century for fortification reasons, is part of the city walls of the old town of Thessaloniki. The tower is a cylindrical masonry building and has been considered as part of the cultural heritage of humanity by the UNESCO World Heritage Committee. Today it presents some major damage to its load bearing system, including intense cracking, moisture damage and disintegration of mortar, bricks and stones. An extensive research study for the evaluation of the tower’s bearing capacity, as well as for the suggestion of efficient strengthening interventions was held, in order to effectively prolong its expected lifetime. To this purpose, refined analytical models of 3D finite elements have been formed and used for the estimation of the elastic and inelastic tower’s response to gravity and seismic loads. Results’ evaluation of several static and dynamic analyses showed that the tower’s stability is not at risk under the action of gravity loads in general, but it’s bearing capacity under strong seismic excitations is questionable, thus becoming obvious the necessity of strengthening interventions. An invertible intervention of strengthening the tower with proper sets of external pre-stressed steel rings was also examined. Linear (elastic) analyses showed that they cannot sufficiently evaluate the effectiveness of this strengthening process. Inelastic analyses, using material laws of Drucker-Prager’s type, showed that the use of prestressed steel rings can significantly reduce the plastic strains’ appearance and therefore the cracking in the masonry walls of the monument.

Compressive Failure of Fiber Composites: The Roles of Multiaxial Loading and Creep

1993 ◽  
Vol 115 (3) ◽  
pp. 308-313 ◽  
Author(s):  
W. S. Slaughter ◽  
N. A. Fleck ◽  
B. Budiansky
Keyword(s):  
Strain Hardening ◽  
Failure Surface ◽  
Kink Band ◽  
Fiber Composites ◽  
Analytical Models ◽  
Fiber Direction ◽  
Multiaxial Loading ◽  
Compressive Failure ◽  
Perfectly Plastic ◽  
Remote Stress

The roles of multiaxial loading and creep in compressive failure of aligned fiber composites are considered. Analytical models are developed based on the model given by Budiansky and Fleck (1992). The critical microbuckling stress in multiaxial loading is calculated for a rigid-perfectly plastic solid and an elastic-plastic strain hardening solid. The rigid-perfectly plastic results predict a plane compressive failure surface in stress space. The rigid-perfectly plastic results are sufficiently accurate, when compared to the strain hardening results, so long as the remote shear stress and stress normal to the fiber direction are not too large relative to the remote stress in the fiber direction. The model given for creep microbuckling is suitable for power law viscous composite behavior. Deformation within a localized kink band is computed as a function of time. A creep life is predicted, based on a critical strain failure criterion.

scholarly journals Experimental Investigation of the Temperature Effect on the Mechanical Properties of Hemp Woven Fabrics Reinforced Polymer

2021 ◽  
Vol 2 (2) ◽  
pp. 239-256
Author(s):  
Sheedev Antony ◽  
Abel Cherouat ◽  
Guillaume Montay
Keyword(s):  
Mechanical Properties ◽  
Elevated Temperatures ◽  
Natural Fiber ◽  
Compression Molding ◽  
Fiber Composites ◽  
Woven Fabrics ◽  
Thermoplastic Composite ◽  
Analytical Models ◽  
Natural Fiber Composites ◽  
Thermal Compression

Natural fiber composites are widely used in a several industrial applications due to their outstanding biodegradability and recyclability. Thermal compression molding is a rapid and easy method to fabricate composite sheets. To better understand the manufacturing process and evaluate the mechanical properties of hemp woven fabrics reinforced thermoplastic composite at elevated temperatures, a detailed investigation is required. In this study, composite sheets were initially fabricated using hemp fiber fabrics (taffeta and serge 2×1) and polypropylene sheets by the thermal compression molding process. Mechanical tests (uniaxial, shear, and biaxial) were carried out at temperatures ranging from 20 to 160 ∘C in order to estimate the mechanical properties of composite sheets. Non-linear behavior was observed during the loading due to the unbalanced weaving pattern of hemp fabric. The biaxial behavior of the composite was estimated using a theoretical method for fabric strength prediction taking into account the interaction effect between the yarns. The experimental results demonstrate that, at high temperature, the polymer softens and the fiber reinforcements dismantle which resulting in a decrease in the mechanical properties of the composite. Two analytical models (Ha & Springer and thermal expansion coefficient) were also proposed to estimate the thermo-mechanical properties of natural fiber composites subjected to various temperatures.

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