Composite beams

Fisher, S., Rosensaft, M. and Marom, G. (1986). Dependence of the interlaminar shear strength on the loading span-to-depth ratio in aramid fiber-reinforced beams. Composites Sci. Technol. 25, 69-73. 

There have been many intereshng approaches to overeome the shortage of high quality, large dimension hmber. Engineers have turned to trusses, I-beams, and space frames to achieve what had previously been aeeomplished by solid timber beams. Composites like glulam and the new produets diseussed below provide substitute elements that can be incorporated into the kinds of modem designs just alluded to. The thmst in the development of these new produets has been improved... 

A technique that has been used successfully to determine beam composition, as far as electronic states are concerned, was first applied to the area of ion-molecule reactions by Turner, et al.18 The method consists of measuring the attenuation of the beam in an appropriate gas as a function of the pressure of that gas. When an ion beam containing ions in a single electronic state (i) passes through a reaction chamber of length l containing a gas whose pressure can be varied, it will be attenuated in an exponential manner... 

Aram, M. R., C. Czaderski and M. MotavaUi (2008a). Debonding failure modes of flexural FRP-strengthened RC beams. Composites Part B Engineering 39(5) pp. 826-841. 

Czaderski, C. and M. Motavalli (2004). Fatigue behaviour of CFRP F-shaped plates for shear strengthening of RC T-beams. Composites Part B Engineering 35(4) pp. 279-290. 

Mottram, J.T. Lateral-torsional buckling of a pultruded I-beam, Composites,... 

Fujita A, Hamada H, Maekawa Z, Uozumi T, Okauji T, Ohno E, I-beam composites with three-dimensional braiding structure- fabrication and mechanical properties. Proceedings, TexComp-2, Leuven, Belgium, May 17-19, 1994. 

Garden HN, Hollaway LC, An experimental study of the influence of plate end anehorage of carbon fibre composite plates used to strengthen reinforced concrete beams. Composite... 

Although the quantitative nature of the KEMS technique was indicated in the introduction, it is important to reiterate it at the start of a discussion of the ion source, mass analysis, and detector. The aim of this technique is to measure the relative partial pressure of vapor species in equilibrium with a condensed sample as a function of sample composition and absolute temperature. The pressure of each species is measured indirectly by sampling its flux in a molecular beam by ionization and analysis of the ion beam. Ideally, the ion beam composition is representative of the molecular beam however, the indirect nature of these measurements introduces a range of factors that affect the measured intensities in the mass spectra. These factors are unrelated to sample composition and temperature. Clearly then, the goal is to reduce the effect and variation of these other factors to allow the accurate study of vapor pressure with temperature and sample composition. The next section briefly discusses the aspects of mass spectrometry with the aim of identifying the other factors and indicating how their effects can be reduced to provide accurate measurement of thermodynamic activities. 

Liu, X. L. (2001), Numerical modeling on pultrusion of composite I beam . Composites Part A Applied Science and Manufacturing, 32, 663-681. 

Composite Lumbers and Beams. Composite lumbers and beams comprise a large and diverse family of products known as engineered wood products (EWPs). EWPs include laminated veneer lumber (LVL), laminated strand lumber (LSL), parallel strand lumber (PSL), glulam, and I-joists, among others. 

Chakrabortty, A., Khennane, A., Kayali, O., and Morozov, E. (2011), Performance of outside filament wound hybrid FRP-concrete beams , Composites Part B Engineering, 42(4), 907-915... 

Ahmed, A., Kodur, V.K.R. (2011). Effect of bond degradation on fire resistance of FRP-strengthened reinforced concrete beams. Composites Part B, 42, 226-237. doi 10.1016/j. composi tesb.2010.11.004... 

CUR96 (2003), Recommendation 96 Fibre-Reinforced Polymers in Civil Load-bearing Structures, CUR commission C124, CUR, Gouda, The Netherlands (in Dutch). Davalos J F, Qiao P and Salim H A (1997), Hexural-torsional buckling of pultruded fiber reinforced plastic composite I-beams, Composites Structures, Vol. 38, Nos. 1-4, pp. 241-250. 

Shan L Y and Qiao P Z (2005), Flexural-torsional buckling of fiber-reinforced plastic composite open channel beams. Composite Structures, Vol. 68, No. 2, pp. 211-224. 

Turvey G J (1996a), Lateral buckling tests on rectangular cross-section pultruded GRP cantilever beams. Composites B, Vol. 27B, No. 1, pp. 35-42. 

Compared to common monolithic beams, composite beams with deformable shear connection present additional difficulties. Even in very simple structural systems (e.g., simply supported beams), complex distributions of the interface slip and force can develop. Different finite elements of composite beams with deformable shear connection have been developed and presented in the literature (Spacone El-Tawil 2004, Dall Asta 8c Zona 2004). These elements include suitable models describing section deformations in order to compute the section force resultants of steel-concrete composite members. This requires the use of realistic material constitutive models for beam steel, reinforcement steel, concrete, and shear-slip behaviour of the studs connecting the two structural components (Zona et al. 2005, 2006, Barbato et al. 2007). 

The second method, oxalate precipitation of rare earth standards, provides chemically bonded constituents. However, relative reproducibilities of 17 percent were obtained with this type of preparation, only slightly better than with dry blended standards. A source of error in attempting broad range quantification of different intensity levels is the fluctuation in the total ion beam composition at the beam monitor. Any determinations dependent upon relative exposure levels will include this error. 

Storage modulus and tan 6 of sandwich laminate beam composites were compared in Figure 14. Storage modulus of epoxy laminate beam was in high contrast with all other copolymer laminates all of copolymer laminates except G-25 showed similar shape over the temperature range, significant drop at transition temperature and immediate recovery at higher temperature... 

The shape of the potential surface can be used to determine energy levels and partition functions and consequently the equilibrium constant for van der Waals molecule formation. This is done elsewhere.A typical result is that gaseous argon cooled to near its normal boiling point, where kT = De, contains a few percent of the dimer Ar2- Samples of similarly cooled nitrogen, oxygen, or hydrogen contain comparable concentrations of (N2)2j ( 2)29 r (H2)2-The use of supersonic nozzles produces beams characterized by temperatures often less than 10 K. Under these conditions the beam composition will be dominated by van der Waals molecules. 

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