Natural frequencies of bonded and unbonded prestressed beams–prestress force effects

Hamed, Ehab; Frostig, Y.

doi:10.1016/j.jsv.2005.11.032

Cited by 96 publications

(81 citation statements)

References 8 publications

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…According to their findings, the frequency of vibrations decreases as prestressing force increases. Hamed and Frostig (2006) developed a nonlinear analytical model for dynamic behavior of prestressed beams with bonded and unbonded tendons. Based on the derived governing equations authors proved that the magnitude of prestressing force does not affect the natural frequencies of bonded or unbonded prestressed beams.…”

Section: Theoretical Investigationsmentioning

confidence: 99%

“…Based on existing literature (for instance the work by Hamed and Frostig 2006) it is demonstrated that, assuming linear elasticity, the magnitude of the prestress force does not affect the natural frequencies of PRC beams in both cases of bonded and unbonded strands that undergo the same transversal displacement of concrete sections during vibration. In the case of unbonded straight tendons, concrete element could vibrate without dragging in vibration prestressing tendons.…”

Section: Compression Softeningmentioning

confidence: 99%

See 1 more Smart Citation

On the Evaluation of Prestress Loss in PRC Beams by Means of Dynamic Techniques

Breccolotti

2018

Int J Concr Struct Mater

View full text Add to dashboard Cite

In the last few decades, prestressing techniques have been used to build very important structures and infrastructures. Since the serviceability and the safety of prestressed reinforced concrete (PRC) elements rely on the effective state of prestressing, development of tools and procedures capable of estimating the effective prestress loss would be very useful. Amongst other techniques, dynamic identification has proved to be an economical, quick and reliable method to evaluate structural integrity. However, the influence of prestressing in the dynamic behavior of PRC elements is not completely clear. In fact, while many references in the literature state that the prestressing force does not affect the frequencies of vibration, almost every experimental test carried out on PRC beams shows an increase in the eigenfrequencies for increasing value of the prestressing force. This paper aims to contribute to the debate, investigating the dynamic behaviour of PRC beams taking into account properties, such as nonlinearity, softening, confinement and micro-cracking of concrete subjected to compression and tension stress states, and the variation of the flexural stiffness of the PRC beam along its length according to bending stress distribution. Non-linear discrete modelling, in combination with system identification and optimization was used to define the dynamic properties of PRC beams, taking into account the effect of prestressing level. The proposed model was applied to four PRC beams with known mechanical and dynamic properties in literature. The influence of the prestressing force on the trend of frequencies of vibration was closely captured for each beam, with errors less than 3% of the estimated frequencies. The results of this investigation thus indicate that dynamic identification techniques can potentially be used to identify the prestressing force level, and consequently the prestress loss, provided the complete concrete mechanics is taken into account.

show abstract

Section: Theoretical Investigationsmentioning

confidence: 99%

Section: Compression Softeningmentioning

confidence: 99%

On the Evaluation of Prestress Loss in PRC Beams by Means of Dynamic Techniques

Breccolotti

2018

Int J Concr Struct Mater

View full text Add to dashboard Cite

show abstract

“…The results of examining the static and dynamic characteristics of the structure with the prestressing system show that the natural frequency and displacement of the structure were the most representative characteristics [7,8,10,12]. In other words, the largest change in natural frequency and displacement is expected when a change occurs in the magnitude of the prestress force on the bonded tendon in the reactor building.…”

Section: Scale-model Specimensmentioning

confidence: 99%

“…Such non-destructive tests have been shown to have several problems-for instance, weakened signal detection due to the use of concrete and grouting materials, and difficulties related to the installation of a sensor on the tendon embedded within the structure [3]. Thus, technology is being developed to analyze the loss of prestress force and to predict prestress force through the SI technique, which uses the dynamic characteristics, strain, or displacement of the structure according to the prestress force [4][5][6][7][8][9][10][11].…”

Section: Introductionmentioning

confidence: 99%

A Sensitivity Analysis of the Key Parameters for the Prediction of the Prestress Force on Bonded Tendons

Jang¹,

Lee²,

Hwang³

et al. 2010

Nuclear Engineering and Technology

View full text Add to dashboard Cite

“…4 The potential influence of prestress on resonance frequencies was also assessed, and the results showed that prestress depended on water depth. 5 Moreover, prestress can be used as a parameter to change the natural frequencies of a mechanical system in a proposed model of the prestressed structure. 6 Thin cylindrical shells are widely used in complex structures, such as aerospace, marine, mechanical, and civil constructs.…”

Section: Introductionmentioning

confidence: 99%

Acoustic Characteristic Analysis of Prestressed Cylindrical Shells in Local Areas

Chen¹,

Liu²

2016

IJAV

View full text Add to dashboard Cite

The influence of prestress on dynamic responses and acoustic radiation for thin cylindrical shells is analyzed in this study. The strain-displacement equation of cylindrical shells with prestress in local areas is established based on the Flügge theory. The structural-acoustic radiation formulation for prestressed cylindrical shells in local areas is instituted by using the variational principle. A numerical analysis is then carried out. The numerical results are validated by comparing the influence of prestress on acoustic radiation power and directivity. This study shows that prestress significantly affects the dynamic characteristics of cylindrical shells.

show abstract

Natural frequencies of bonded and unbonded prestressed beams–prestress force effects

Cited by 96 publications

References 8 publications

On the Evaluation of Prestress Loss in PRC Beams by Means of Dynamic Techniques

On the Evaluation of Prestress Loss in PRC Beams by Means of Dynamic Techniques

A Sensitivity Analysis of the Key Parameters for the Prediction of the Prestress Force on Bonded Tendons

Acoustic Characteristic Analysis of Prestressed Cylindrical Shells in Local Areas

Contact Info

Product

Resources

About