Dynamic and Earthquake Behaviour of Greek Post-Byzantine Churches with Foundation Deformability—Experimental Investigation of Stone Masonry Material Properties

2015 ◽  
pp. 235-264 ◽  
Author(s):  
George C. Manos ◽  
Lambros Kotoulas ◽  
Vasiliki Matsou ◽  
Olympia Felekidou
Keyword(s):  
Experimental Investigation ◽  
Material Properties ◽  
Stone Masonry ◽  
Masonry Material

Experimental Investigation of Mechanical Behavior of a Polyamide before and after Constrained Groove Pressing Process

2018 ◽  
Vol 36 ◽  
pp. 25-36
Author(s):  
Mohammed Salah Bennouna ◽  
Benaoumeur Aour ◽  
Fatiha Bouaksa ◽  
Saad Hamzaoui
Keyword(s):  
Experimental Investigation ◽  
Mechanical Behavior ◽  
Tensile Properties ◽  
Material Properties ◽  
Hold Time ◽  
Thermoplastic Polymer ◽  
Processed Material ◽  
Before And After ◽  
Number Of Cycles ◽  
Number Of Passes

In this paper an experimental investigation of mechanical behavior of a thermoplastic polymer (polyamide PA 66) processed by constrained groove pressing (CGP) using several passes is presented. To this end, corrugating and straightening tools are designed and manufactured. The effects of the number of passes and the hold time on the mechanical behavior of the polyamide have been highlighted. The obtained results show that the material properties and the microstructure are significantly altered under CGP process. It has been found that the microhardness and the tensile properties have been progressed accordingly to the number of cycles, especially when the samples are processed using a hold time of five minutes. Hence, it can be concluded that this latter plays a very important role on the reorientation and stabilization of the microstructure when the processed material is a polymer.

Aspects of Experimental Errors and Data Reduction Schemes From Spherical Indentation of Isotropic Materials

2014 ◽  
Vol 136 (3) ◽  
Author(s):  
J. K. Phadikar ◽  
T. A. Bogetti ◽  
A. M. Karlsson
Keyword(s):  
Sensitivity Analysis ◽  
Experimental Investigation ◽  
Monte Carlo ◽  
Condition Number ◽  
Data Reduction ◽  
Material Properties ◽  
Analytical Method ◽  
Systematic Investigation ◽  
Spherical Indentation ◽  
Experimental Errors

Sensitivity to experimental errors determines the reliability and usefulness of any experimental investigation. Thus, it is important to understand how various test techniques are affected by expected experimental errors. Here, a semi-analytical method based on the concept of condition number is explored for systematic investigation of the sensitivity of spherical indentation to experimental errors. The method is employed to investigate the reliability of various possible spherical indentation protocols, providing a ranking of the selected data reduction protocols from least to most sensitive to experimental errors. Explicit Monte Carlo sensitivity analysis is employed to provide further insight of selected protocol, supporting the ranking. The results suggest that the proposed method for estimating the sensitivity to experimental errors is a useful tool. Moreover, in the case of spherical indentation, the experimental errors must be very small to give reliable material properties.

Material properties of existing unreinforced clay brick masonry buildings in New Zealand

2014 ◽  
Vol 47 (2) ◽  
pp. 75-96 ◽  
Author(s):  
Nasser Almesfer ◽  
Dmytro Y. Dizhur ◽  
Ronald Lumantarna ◽  
Jason M. Ingham
Keyword(s):  
New Zealand ◽  
Material Properties ◽  
Research Programme ◽  
Unreinforced Masonry ◽  
Clay Brick ◽  
In Situ Testing ◽  
Brick And Mortar ◽  
Masonry Material ◽  
Assessment Guidelines

The material properties of New Zealand’s heritage clay brick unreinforced masonry (URM) buildings were investigated and are reported herein. Material data was collected from a total of 98 New Zealand clay brick URM buildings and a database was compiled that was comprised of various masonry material properties. The intention behind the reporting of information and data presented herein was to provide indicative values to the professional engineering community to aid as preliminary input when undertaking detailed building assessments for cases where in-situ testing and brick and mortar sample extraction are not feasible. The data presented is also used to support the relationships for URM material properties that have been recommended by the authors for incorporation into the next version of the NZSEE seismic assessment guidelines for URM buildings. Although researchers from Europe, USA, India and Australia have previously studied the material properties of clay brick unreinforced masonry, knowledge on New Zealand URM material properties was poor at the time the study commenced. Therefore, a research programme was undertaken that was focused on both in-situ testing and laboratory testing of samples extracted from existing New Zealand clay brick URM buildings.

Experimental investigation on the seismic performance of PP-band strengthening stone masonry houses

2013 ◽  
Vol 11 (6) ◽  
pp. 2177-2196 ◽  
Author(s):  
Navaratnarajah Sathiparan ◽  
Kotaro Sakurai ◽  
Muneyoshi Numada ◽  
Kimiro Meguro
Keyword(s):  
Experimental Investigation ◽  
Seismic Performance ◽  
Stone Masonry

ANALYSIS OF THE EFFECTS OF LAMINATE DEPTH AND MATERIAL PROPERTIES ON THE DAMPING ASSOCIATED WITH LAYERED STRUCTURES IN A PRESSURIZED ENVIRONMENT

2010 ◽  
Vol 34 (2) ◽  
pp. 165-196 ◽  
Author(s):  
Vincent O. S. Olunloyo ◽  
Olatunde Damisa ◽  
Charles A. Osheku ◽  
Ayo A. Oyediran
Keyword(s):  
Experimental Investigation ◽  
Energy Dissipation ◽  
Dynamic Loading ◽  
Material Properties ◽  
Interface Pressure ◽  
Special Configuration ◽  
Damping Decrement ◽  
Laminate Materials ◽  
Laminate Thickness ◽  
Operational Methods

In aerodynamic and machine structures, one of the effective ways of dissipating unwanted vibration or noise is to exploit the occurrence of slip at the interface of structural laminates where such members are held together in a pressurised environment. The analysis and experimental investigation of such laminates have established that when subjected to either static or dynamic loading, non-uniformity in interface pressure can have significant effect on both the energy dissipation and the logarithmic damping decrement associated with the mechanism of slip damping. Such behaviour can in fact be effectively exploited to increase the level of damping available in such a mechanism. What has however not been examined is to what extent is the energy dissipation affected by the relative sizes or the material properties of the upper and lower laminates? In this paper the analysis is extended to incorporate such effects. In particular, by invoking operational methods, it is shown that variation in laminate thickness may provide less efficacious means of maximizing energy dissipation than varying the choice of laminate materials but that either of these effects can in fact dwarf those associated with non-uniformity in interface pressure. To achieve this, a special configuration is required for the relative sizes and layering of the laminates. In particular, it is shown that for the case of two laminates, the upper laminate is required to be thinner and harder than the lower one. These results provide a basis for the design of such structures.

Experimental investigation of the curing behaviour of fibre composite structures with snap-cure polymer systems

2018 ◽  
Vol 9 (6) ◽  
pp. 768-778
Author(s):  
Rafal Stanik ◽  
Albert Langkamp ◽  
Michael Müller ◽  
Maik Gude ◽  
Anna Boczkowska
Keyword(s):  
Experimental Investigation ◽  
Temperature Field ◽  
Process Parameters ◽  
Material Properties ◽  
Manufacturing Process ◽  
Composite Structures ◽  
Fibre Composite ◽  
Uniform Design ◽  
Curing Process ◽  
Content Type

PurposeNovel snap-cure polymers (SCPs), as matrix systems for high-performance fibre composite materials, provide high potential for manufacturing of component families with small batch sizes and high variability. Especially, the processing of powdered SCP is associated with relatively simple and inexpensive tools. In addition, because of their curing behaviour, they allow short tooling times so that the production of small batch size components is possible in relatively short cycle times. To enable an efficient manufacturing process, an understanding of the curing process is necessary. An adjustment of the process parameters for a uniform design of the temperature field in the material during the manufacturing process is essential. The paper aims to discuss this issue.Design/methodology/approachFor this, a powder SCP resin system was investigated under process-specific conditions. An experimental test approach for determination of various thermal and kinetic material properties was developed. For the adjustment of the process parameters and monitoring of the curing state during the manufacturing process, a kinetic material model was determined. In the end, the validation of the determined model was performed. For this, the temperature distribution under process- specific conditions was measured in order to monitor the curing state of the material.FindingsThe experimental investigation showed an uneven temperature field in the material, which leads to an inhomogeneous curing process. This can lead to residual stresses in the structure, which have a critical impact on the material properties.Originality/valueThe determined kinetic model allows a prediction of the curing reaction and adjustment of the process parameters which is essential, especially for thick-walled components with SCPs.

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