Showing papers on "Durability published in 2005"
TL;DR: A comprehensive review of the literature on the durability of fiber-reinforced composite (GFRP) bars indicates a significant increase in the number of studies in this area in the last decade as mentioned in this paper.
Abstract: The research undertaken during the last two decades has shown that one of the potential solutions to the steel-corrosion-related problems in concrete is the use of fiber-reinforced composite (FRP) reinforcement as a replacement for traditional steel bars. Glass FRP (GFRP) reinforcement is gaining more popularity in construction of bridges and in other concrete structures because of its low cost compared to Carbon FRP reinforcement. The durability of these materials, especially under severe environmental conditions, is now recognized as the most critical topic of research. The lack of data on durability of the GFRP reinforcements is a major obstacle to their acceptance on a broader scale in civil engineering.
This paper summarizes the most significant research work published on the durability of FRP bars in the past two decades. A comprehensive review of the literature on the durability of FRP bars indicates a significant increase in the number of studies in this area in the last decade. The durability tests conducted by the authors and others on the latest generation of GFRP bars subjected to stresses higher than the design limits, combined with aggressive mediums at elevated temperatures, have concluded that the strength reduction factors adopted by current codes and guidelines are conservative. These factors were based on limited test results that were carried out on the early generations of the GFRP products, which have now substantially changed.
160 citations
TL;DR: In this paper, the effect of size and grading of the coarse aggregate on the durability and the microstructure characteristics of concrete was investigated and the results indicated that as the proportion of larger size aggregate increases in the mix, the local porosity at the ITZ increases and the overall durability decreases.
151 citations
TL;DR: In this paper, the authors investigated the durability of carbon fiber impregnated in the field using a wet layup process for the rehabilitation of deterioration and understrength concrete structures using a number of exposures including immersion in deionized water, salt and alkali solutions, freeze-thaw, and accelerated aqueous exposure, with composite response determined over a 100 week period through moisture uptake measurements, mechanical characterization, and dynamic mechanical thermal analysis.
Abstract: Carbon fabric impregnated in the field using a wet layup process is increasingly used for the rehabilitation of deterioration and understrength concrete structures. Although the wet layup process affords significant flexibility for application in the field, the use of a manual process in conjunction with the field environment can result in substantial variation in material characteristics, higher void content, non-uniform wetout and compaction between layers and a higher propensity for moisture related deterioration. In order to assess the durability of such systems an investigation is undertaken considering a number of exposures including immersion in deionized water, salt and alkali solutions, freeze-thaw, and accelerated aqueous exposure, with composite response being determined over a 100 week period through moisture uptake measurements, mechanical characterization, and dynamic mechanical thermal analysis. It is shown that while strength characteristics can degrade significantly due to deterioration at the matrix and interface levels, modulus is relatively less affected. Changes in mechanical characteristics are correlated with level of moisture uptake and a relationship between uptake and glass transition temperature is demonstrated. The data provides the basis for a fundamental understanding of uptake related correlations and deteriorative mechanisms that could be used for purposes of future reliability and service-life estimation.
151 citations
TL;DR: In this paper, a hydroxyl-functional organophosphorus oligomer (FR) was used for flame retardant finishing of 50/50 cotton/nylon fabrics.
96 citations
TL;DR: In this paper, a model of glass fiber reinforced concrete (grc) degradation, based on the glass technology principle of static fatigue, was applied to a large body of diverse data, some collected from both industry and open literature and some generated by the authors.
Abstract: This paper applies a model of glass fibre reinforced concrete (grc) degradation, based on the glass technology principle of static fatigue, to a large body of diverse data, some collected from both industry and open literature and some generated by the authors. Activation energies for the strength loss process in OPC and modified matrix grcs are derived and it is shown that the modified matrix grcs degrade by a different mechanism to OPC grc. In consequence, using traditional acceleration factors to predict the long term behaviour of modified matrix grc can lead to severe over-estimation of durability. It is also concluded that hot water ageing is not suitable for polymer modified grc and that ageing at temperatures over 65 °C may lead to the activation of strength loss processes not encountered during natural weathering in some matrices.
85 citations
TL;DR: In this article, the effect of acidity of water (slaking fluid) on slake durability index of shale in the laboratory is investigated and a model was developed and compared with two other models, namely, Neuro-fuzzy systems (combination of fuzzy and artificial neural network systems) and Artificial Neural Network system, for the prediction of shaly rock to evaluate the performance of its prediction capability.
Abstract: More than 35% of the earth’s crust is comprised of clay-bearing rocks, characterized by a wide variation in engineering properties and their resistance to short term weathering by wetting and drying phenomenon The resistance to short-term weathering can be determined by slake durability index test There are various methods to determine the slake durability indices of weak rock The effect of acidity of water (slaking fluid) on slake durability index of shale in the laboratory is investigated These methods are cumbersome and time consuming but they can provide valuable information on lithology, durability and weather ability of rock Fuzzy set theory, Fuzzy logic and Artificial Neural Networks (ANN) techniques seem very well suited for typical complex geotechnical problems In conjunction with statistics and conventional mathematical methods, a hybrid method can be developed that may prove a step forward in modeling geotechnical problems During this investigation a model was developed and compared with two other models ie, Neuro-fuzzy systems (combination of fuzzy and artificial neural network systems) and artificial neural network system, for the prediction of slake durability index of shaly rock to evaluate the performance of its prediction capability
75 citations
TL;DR: In this paper, a model for predicting the long-term behaviour of textiles made of glass filaments in concrete, which is based on the physico-chemical background of degradation, is presented.
Abstract: A main topic of consideration for glass-fibre reinforced cementitious composites is their durability. Recent developments of new cementitious matrices and advances in chemical composition and sizing of glass fibres lead to increased durability of cementitious composites with glass fibre reinforcement. Still, the relative importance of the main degradation mechanisms is not fully understood. A joint experimental program at RWTH-Aachen (Germany) and VUB-Brussels (Belgium) shows that the pH of the matrix has a considerable influence on the durability of the studied composite. Recent investigations on single filaments in high alkalinity solutions and on rovings in concrete show that filaments lose strength mainly due to chemical attack in local weak points of the glass structure. Once this chemical attack becomes diffusion controlled, further corrosion slows down to a considerably lower rate. The aim of these investigations is to finally build a model, allowing prediction of the long-term behaviour of textiles—made of glass filaments—in concrete, which is based on the physico-chemical background of degradation.
65 citations
TL;DR: In this paper, the thermal-mechanical durability of the Pb-free Sn3.8Ag0.7Cu solders is investigated by a systematic approach combining comprehensive thermal cycling tests and finite element modeling.
Abstract: As the ban of the Pb use in electronics products is approaching due to the waste electrical and electronic equipment (WEEE) and restriction of hazardous substances (ROHS) directives, electronics companies start to deliver the products using the Pb-free solders. There are extensive databases of mechanical properties, durability properties (for both mechanical and thermal cycling), and micromechanical characteristics for Sn-Pb solders. But similar databases are not readily yet available for Pb-free solders to predict its mechanical behavior under environmental stresses. In this study, the thermo-mechanical durability of the Pb-free Sn3.8Ag0.7Cu solder is investigated by a systematic approach combining comprehensive thermal cycling tests and finite element modeling. A circuit card assembly (CCA) test vehicle was designed to analyze several design and assembly process variables when subjected to environmental extremes. The effects of mixed solder systems, device types, and underfill are addressed in the thermal cycling tests. The thermal cycle profile consisted of temperature extremes from −55to+125° Celsius with a 15min dwell at hot, a 10min dwell at cold, and a 5–10° Celsius per minute ramp. Thermal cycling results show that Sn3.8Ag0.7Cu marginally outperforms SnPb for four different components under the studied test condition. In addition, the extensive detailed three-dimensional viscoplastic finite element stress and damage analysis is conducted for five different thermal cycling tests of both Sn3.8Ag0.7Cu and Sn37Pb solders. Power law thermo-mechanical durability models of both Sn3.8Ag0.7Cu and Sn37Pb are obtained from thermal cycling test data and stress and damage analysis. The results of this study provide an important basis of understanding the thermo-mechanical durability behavior of Pb-free electronics under thermal cycling loading and environmental stresses.
58 citations
Patent•
15 Jul 2005
TL;DR: In this article, an ion beam is used to treat an IR reflecting layer(s) of such a coated article to improve sheet resistance (RS) properties, emittance, solar control properties, and/or durability of the article.
Abstract: A coated article is provided that may be used as a vehicle windshield, insulating glass (IG) window unit, or the like. An ion beam is used to treat an infrared (IR) reflecting layer(s) of such a coated article. Advantageously, this has been found to improve sheet resistance (RS) properties, emittance, solar control properties, and/or durability of the coated article.
55 citations
21 Apr 2005-Nuclear Instruments & Methods in Physics Research Section A-accelerators Spectrometers Detectors and Associated Equipment
TL;DR: In this paper, the authors compared the neutron radiography capability to obtain quantitative data for porosity and sorptivity in concrete to laboratory or conventional measurements, and investigated the effects that water to cement ratio and curing time have on the durability of concrete.
Abstract: The ability of concrete to withstand the penetration of liquid and oxygen can be described as the durability of concrete. The durability of concrete, can in turn, be quantified by certain characteristics of the concrete such as the porosity, sorptivity and permeability. The quantification of neutron radiography images of concrete structures and, therefore, the determination of concrete characteristics validate conventional measurements. This study compares the neutron radiography capability to obtain quantitative data for porosity and sorptivity in concrete to laboratory or conventional measurements. The effects that water to cement ratio and curing time have on the durability of concrete are investigated.
52 citations
TL;DR: In this article, an innovative approach based on fracture mechanics and local bond shear stress-slip relationships is proposed to explain the degradation mechanism of a 90 cm-long plain concrete beam reinforced with externally bonded wet-laid glass fiber reinforced polymer sheets.
Abstract: In this investigation, 90-cm-long plain concrete beam specimens reinforced with externally bonded wet-laid glass fiber reinforced-polymer sheets are investigated. The specimens are precracked with a three point flexural load, subjected to a constant four point flexural load of about 25% of the initial ultimate moment, and placed into different environmental conditions. The four environmental conditions under investigation are indoor laboratory, outdoor, elevated temperature/dry, and freeze/thaw. By varying the exposure time in different environments and using the photoelastic coating method to evaluate strain distributions, the durability of the externally reinforced concrete beams is evaluated. An innovative approach based on fracture mechanics and local bond shear stress-slip relationships is proposed to explain the degradation mechanism. This approach is capable of qualitatively and quantitatively characterizing the environmental effect in terms of the parameters of the shear stress-slip law. Four one-dimensional shear stress-slip relationships are evaluated in terms of their ability to model the environment-dependent strain distribution and debond data obtained in the present investigation.
01 Jan 2005
TL;DR: In this paper, a combination of sprayed concrete technique and steel fibre technology gives obvious advantages when saving the work needed to place conventional reinforcement, in rock strengthening applications. But it is not suitable for outdoor applications.
Abstract: A combination of sprayed concrete technique and steel fibre technology gives obvious advantages when saving the work needed to place conventional reinforcement. In rock strengthening applications t ...
TL;DR: In this article, the properties and preliminary durability of ceramic fiber reinforced Portland cement composites tested with wet-hot accelerating method were investigated, and the results showed that the effect of the flexural reinforcement was influenced by various factors, including fiber length, fiber content and kinds of matrices.
TL;DR: In this article, a service lifetime prediction method for polyvinyl chloride (PVC) and high temperature modified polycarbonate copolymer (coPC) glazing materials is presented.
23 Oct 2005
TL;DR: In this paper, the effects of printed circuit board (PCB) material on interconnect durability of lead free assemblies were investigated and two kinds of environmental loadings were simulated: temperature cycling and random vibration loading, and the results showed that PI board provides a better solder joint durability than FR4 and high T g FR4 under temperature cycling conditions.
Abstract: This study investigates the effects of printed circuit board (PCB) material on interconnect durability of lead free assemblies. The assemblies involve soldering various packages (array and peripheral) on to FR4, high glass transition temperature (T g ) FR4 and Polyimide (PI) printed circuit boards using Sn3Ag0.5Cu solder alloy. The glass transition temperature of these materials ranges from 130°C to 230°C. Thermomechanical properties, such as elastic modulus and thermal expansion coefficients, of the board materials vary considerably. These properties have a direct impact on the interconnect durability. In this paper, thermomechanical properties are experimentally determined and used for solder joint durability simulation. Two kinds of environmental loadings are simulated: temperature cycling and random vibration loading. The results show that PI board provides a better solder joint durability than FR4 and high T g FR4 under temperature cycling conditions. PI assembly has better durability than FR4 assembly under random vibration. The paper also presents the effect of temperature on the vibration response of the FR4 printed circuit board assemblies. The understanding of these changes can contribute to the study on interconnect durability under combined temperature cycling and vibration loading conditions.
01 Jan 2005
Journal Article•
TL;DR: The Formosan subterranean termite (Coptotermes formosanus Shiraki) in southern Louisiana have caused damage estimated in the hundreds of millions of dollars.
Abstract: FEBRUARY 2005 Over 95 percent of the approximate1y 1.5 million homes constructed in the United States each year are framed with wood, the world’s most sustainable building material. Wood-based composites, including structural composite panels and engineered composite lumber, are being increasingly utilized in both interior and exterior applications and frequently are the principal structural elements in buildings. These applications include sheathing, floors, Ibeams, door and window components, joists, and molded wall panels as both skin and structural elements. The exterior application of structural wood composites has led to increased exposure of the materials to wetting, and consequently, to decay fungi and insects (primarily termites). For example, widespread infestations of the Formosan subterranean termite (Coptotermes formosanus Shiraki) in southern Louisiana have caused damage estimated in the hundreds of millions of dollars. Formosan subterranean termites pose a major threat to all cellulosic building materials because they consume wood much faster than native subterranean termites, and their colonies are more than 10 times larger than those of native termites. It is the most destructive insect in Louisiana. Other states recording infestations include Alabama, California, Florida, Georgia, Hawaii, Mississippi, North Carolina, South Carolina, Tennessee, and Texas. Mold, decay, and other moisture-related problems have also led to significant economic losses in the building industry. Wood composites are particularly vulnerable to these biological attacks, if unprotected. Durability concerns have historically been addressed through the use of chemical treatments employing a variety of application methods, includ-
18 May 2005
TL;DR: The U.S. Naval Research Laboratory (NRL) has developed two unique materials with excellent properties for various military and commercial applications in the UV-Vis-IR wavelength range as discussed by the authors.
Abstract: The U.S. Naval Research Laboratory (NRL) has developed two unique materials with excellent properties for various
military and commercial applications in the UV-Vis-IR wavelength range. These materials are: an amorphous Barium
Gallo-Germanate (BGG) glass and a polycrystalline Magnesium Aluminate Spinel. The BGG glass is made using
traditional glass melting techniques, and was developed as a low cost alternative to the currently used window materials.
Large prototype windows have been fabricated for a Navy reconnaissance program. BGG windows have been
successfully tested for environmental ruggedness (MIL-F-48616) and rain erosion durability up to 300 mph. BGG glass
is currently under development and evaluation for High Energy Laser (HEL) applications. A new process has been
developed to sinter spinel to clear transparency with very high yields. This process has been used to make various sizes
and shapes (flats and domes) and is readily scalable to industrial sizes to produce large windows & domes for various
applications. NRL has also developed modified BGG glasses, which are compatible with Spinel and ALON substrates
for bonding.
09 May 2005
TL;DR: In this paper, an initial sensor durability study was undertaken to better understand the performance and degradation of piezo wafer active sensor (PWAS) systems under adverse mechanical, temperature, and moisture conditions.
Abstract: A key question that needs to be addressed and answered with regard to successfully implementing Structural Health Monitoring technologies in Air Force systems involves the long-term operability, durability, and survivability of integrated sensor systems and their associated hardware. Whether a sensor system is fully integrated within a structural material, or surface-bonded to the structure, a number of environmental and system level influences will tend to degrade the sensor system’s performance and durability over time. In this effort, an initial sensor durability study was undertaken to better understand the performance and degradation of piezo wafer active sensor (PWAS) systems under adverse mechanical, temperature, and moisture conditions. A novel displacement-field imaging approach was utilized to understand the vibration characteristics of PWAS transducers placed in accelerated vibration, temperature-cycling, and moisture-cycling conditions. The results showed damage in the form of PWAS sensor cracking events, bond degradation and failure, as well as indications of performance variation and reduction due to the accelerated exposure levels. Future activities will focus on identifying critical durability and survivability issues through advanced sensor modeling and additional accelerated testing efforts, with the ultimate goal of improving the robustness of health monitoring systems through improved sensor system design and packaging.
TL;DR: In this paper, the role of fiber reinforcement on the durability of cement-based repairs has been investigated, and it is shown that three times as much fiber reinforcement is required to produce laboratory effects similar to those found in the field.
Abstract: Cement-based bonded overlay is a frequently used technique for smoothing a damaged surface and/or restoring or improving the mechanical capacity of a structure by increasing its thickness. It is well established that the durability of such a repair is limited by its debonding from the substrate. Whatever the original cause of this debonding, there is general agreement that cracks cutting the repair layer (or any discontinuity such as joints or boundaries) are systematically involved. In situ repairs have demonstrated that reinforcement with commonly used contents of fibres effectively improves the durability of the repair. However, numerous trials under conventional laboratory conditions have failed to confirm the beneficial effects of the fibre reinforcement and three times as much fibre has been required to produce laboratory effects similar to those found in the field. This paper aims to explain this discrepancy. One part of the explanation may be that cracking due to length change (pre-cracking) is not likely to affect small laboratory specimens. Also, most of the laboratory tests have used monotonic loading (or monotonic straining) cases while fatigue loading would constitute a more realistic test. When such corrections are taken into account, a better understanding is obtained of the actual role of fibre reinforcement on the durability of cement-based repairs, as shown by the results and analysis presented here.
TL;DR: In this paper, the isothermal mechanical durability of three NEMI recommended Pb-free solders, 95.5Sn-3.9Ag-0.6Cu, 96.5sn-3,5Ag, and 99.3sn-0,7Cu, is tested on the TMM setup under two test conditions: room temperature and relatively high strain rate, and high temperature and low strain rate.
Abstract: This study is motivated by the urgent need in the electronics industry for mechanical properties and durability of Pb-free solders because the use of Pb will be banned in the EU by July 1, 2006. The isothermal mechanical durability of three NEMI recommended Pb-free solders, 95.5Sn-3.9Ag-0.6Cu, 96.5Sn-3.5Ag, and 99.3Sn-0.7Cu, is tested on the thermo-mechanical-microscale (TMM) setup under two test conditions: room temperature and relatively high strain rate, and high temperature and low strain rate. The test data are presented in a power law relationship between three selected damage metrics (total strain range, inelastic strain range, and cyclic work density) to 50% load drop. The obtained mechanical durability models of three Pb-free solders are compared with those of the eutectic 63Sn-37Pb solder at the two selected test conditions and at the same homologous temperature of 0.75. The results of this study can be used for virtual qualification of Pb-free electronics during design and development of electronics under mechanical loading.
TL;DR: In this paper, the performance of FTire and LMS CDTire in predicting durability loads is evaluated using a new test setup termed a "suspension on a drum" (SOM).
Abstract: The tyre models FTire and LMS CDTire for multibody simulation have been developed for use in the field of vehicle system dynamics. These tyre models are expected to enable us to predict the forces on the wheel spindle in ride comfort and durability simulations. In this paper, the performance of FTire and LMS CDTire in predicting durability loads is evaluated using a new test setup termed a ‘suspension on a drum’. Both tyre models demonstrated a sufficient level of performance to enable practical application in predicting durability performance.
TL;DR: In this article, an integrated CAD-based computer-aided engineering process was developed to effectively carry out design optimisation for structural durability, yielding a manufacturable, durable, and cost-effective product.
Abstract: Mechanical fatigue subject to external and inertia transient loads in the service life of mechanical systems often leads to structural failure due to accumulated damage. A structural durability analysis that predicts the fatigue life of mechanical components subject to dynamic stresses and strains is a computer-intensive, multidisciplinary simulation process, since it requires the integration of several computer-aided engineering tools and large amounts of data communication and computation. Uncertainties in geometric dimensions result in the indeterministic fatigue life of a mechanical component. Uncertainty propagation to structural fatigue under transient dynamic loading is not only numerically complicated but also extremely expensive. It is, therefore, a challenge to develop a durability-based design-optimisation process and reliability analysis to ascertain whether the optimal design is reliable. The objective of this paper is to develop an integrated CAD-based computer-aided engineering process to effectively carry out design optimisation for structural durability, yielding a manufacturable, durable, and cost-effective product. In addition, a reliability analysis is executed to assess the reliability of the deterministic optimal design.
TL;DR: In this article, the general concepts and ways of implementing computerized feedback control of a multipurpose accelerated concrete durability test system are first presented and applied to frost-resistant assessment of different concretes.
Abstract: Accelerated durability assessment is one of the promising ways to provide a sound basis for service life prediction of concrete. To follow the rapid pace of research in modern concrete technology, an effective accelerated assessment system for concrete durability with automatic control and consistent working performance is highly desired. In this paper, the general concepts and ways of implementing computerized feedback control of a multipurpose accelerated concrete durability test system are first presented and applied to frost-resistant (one of the main durability factors of concrete structures in cold regions) assessment of different concretes. The experimental investigations showed that the newly developed automatic feedback controlled system was reliable and had a promising future for the accelerated durability assessment of concretes. Second, based on the premise that the deterioration mechanisms and the surrounding aggressive environment of the concrete under consideration cannot be precisely descr...
TL;DR: In this article, a study of porcelain insulators used in 25 kV railway traction lines has been conducted and the authors asserted the control exercised by chemical composition, crystalline structural phases and microstructure on the functional reliability and durability of the insulators.
Abstract: The catastrophic failures of porcelain insulators in power lines can be minimized by understanding the structure-property relationship that governs the performance. A study addressing the materials aspects has been conducted on alumina based porcelain insulators used in 25 kV railway traction lines. This article asserts the controls exercised by chemical composition, crystalline structural phases and microstructure on the functional reliability and durability of the insulators. Influences of the total alumina, α-Al2O3 (corundum) and α-quartz contents, microstructural features including morphologies of mullite needles, quartz and corundum grains in the alumino silicate glassy matrix, large inhomogeneities in matrix constituents and composition have been highlighted.
Patent•
28 Dec 2005
TL;DR: In this article, a high-performance anti-erosion marine concrete and its production are disclosed, its advantages include higher durability, strength and chlorine ion permeability, good service behavior and stable size.
Abstract: A high-performance anti-erosion marine concrete and its production are disclosed. Marine concrete consists of cement mixed materials and water, cement mixed materials consist blended material 30i½35wt%, aggregate 70i½76wt%, and water reducer 1.0i½1.4wt%. Its advantages include higher durability, strength and chlorine ion permeability, good service behavior and stable size.
01 Jan 2005
TL;DR: In this article, the effect of disk surface roughness on the above performance characteristics was investigated using low-pressure on-track tests, and the drive-level reliability data were presented to confirm general conclusions reached from the component-level testing.
01 Jan 2005
TL;DR: In this paper, the authors outline recommendations for the durability design of FRP-strengthening measures in Australia, in addition to the identification of much needed areas of further research.
Abstract: It is now reasonably well established that reinforced concrete (RC) structural elements can be strengthened/retrofitted/repaired by bonding high-strength fibre reinforced polymer (FRP) composites Such reasons include steel reinforcement corrosion, construction flaws, change in loading or structure usage, or damage from impact or seismic events Traditional methods of repair can be cumbersome such as section enlargement, post-tensioning, concrete overlays and steel plate bonding A simple effective alternative is the use of externally bonded FRP In addition to their high-strength FRPs offer ease of installation, high corrosion resistance and versatility in coping with different section shapes Considerable research has been reported in the last decade or so on the mechanical behaviour and failure of FRP-strengthened RC elements The level of understanding of structural behaviour has reached a stage where several design guidelines have been developed around the world such as the Concrete Society (2000) report, fib (2001), ISIS (2001), ACI 4402 (2002), and Teng et al (2002) (2002) Limited research on durability issues has resulted in limited design guidance with the most comprehensive treatment given by ACI 4402 (2002) The viability of this new rehabilitation technique has been adequately demonstrated at a structural level but its overall functionality and durability still need to be comprehensively demonstrated Case histories on durability of the composite are not sufficiently documented or not easily accessible to the engineering community (Karbhari et al 2003) and such limitation in knowledge is restricting the wide scale use of FRP composites in rehabilitation works The long term performance of FRP materials has been investigated predominantly in North America, Europe and Japan, though little to no work has been reported in Australia Ways of assessing durability issues of the materials are urgently needed, and considerable work needs to be carried out to develop the acceptance criteria This paper outlines recommendations for the durability design of FRP-strengthening measures in Australia Before doing so a largely qualitative summary of critical areas of durability is given, in addition to the identification of much needed areas of further research