Recent Advances in Structural Health Monitoring and Engineering Structures

Recent Advances in Structural Health Monitoring and Engineering Structures

Author: Ravipudi Venkata Rao

Publisher: Springer Nature

Published: 2022-12-16

Total Pages: 419

ISBN-13: 9811948356

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This book presents the select proceedings of the 2nd International Conference on Structural Health Monitoring & Engineering Structures (SHM&ES 2021) held at the University of Transport and Communications, Hanoi, Vietnam, during 13–14 December 2021. It covers the recent advances in the fields related to structural health monitoring, damage detection and assessment, non-destructive testing, inverse problems, optimization, artificial neural networks, and evaluation. This book will be useful for researchers and professionals working in the field of health monitoring of engineering structures.


Bond and anchorage of embedded reinforcement: Background to the fib Model Code for Concrete Structures 2010

Bond and anchorage of embedded reinforcement: Background to the fib Model Code for Concrete Structures 2010

Author: fib - Fédération internationale du béton

Publisher: fib - Fédération internationale du béton

Published: 2014-05-01

Total Pages: 177

ISBN-13: 2883941122

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As part of the preparation for the fib Model Code for Concrete Structures 2010, task group 4.5 Bond Models undertook a major review of rules for bond and anchorage of reinforcement in the CEB-FIP Model Code 1990. This bulletin presents the outcome of that review, describes the rationale for the revisions and presents the evidence on which the revisions are based. The principle changes in MC2010 include raising the limit on concrete strength that may be used when determining bond resistance to 110MPa, introduction of a coefficient η4 to cater for different reinforcement Classes, and coverage of new construction materials including epoxy coated and headed bars. The format of design rules has been changed to permit more rational treatment of confinement from concrete cover and transverse reinforcement, the contribution of end hooks and bends for tension bars, and end bearing to compression laps. New guidance is provided covering a range of construction techniques and service environments and the influence of long term degradation. Analyses of various aspects of detailing on performance of laps and anchorages have resulted in discontinuation of the ‘proportion lapped’ factor α6, alterations to requirements of transverse reinforcement at laps, and have resolved inconsistencies in provisions for bundled bars between major national codes. Apparent inconsistencies in existing rules for lapped joints and anchorages and between the local bond/slip model and design rules are also resolved, thus allowing integration of application rules and modelling. Finally, the basis for an attempt to introduce simple detailing rules for laps and anchorages is described.


Behavior of UHPC Structural Members subjected to Pure Torsion

Behavior of UHPC Structural Members subjected to Pure Torsion

Author: Mohammed Ismail

Publisher: kassel university press GmbH

Published: 2015-01-01

Total Pages: 287

ISBN-13: 3862199525

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Ultra High Performance Concrete (UHPC) is characterized by a very high compressive strength which may reach more than 200 MPa. The behavior of this material under tension and compression actions has been established to be very brittle in nature. Discontinuous fibers (normally steel fibers) are usually added to the UHPC mix to introduce ductility. In order to investigate the beneficial effects of using fiber reinforced UHPC in structural members subjected to torsion, a series of experimental tests on 17 UHPC beams subjected to pure torsion were carried out. The test beams consisted of plain UHPC beams, UHPC beams reinforced with steel fibers only, UHPC reinforced with steel fibers and different combinations of traditional longitudinal and transverse reinforcement. The plain UHPC beams showed very brittle behavior, whereas the UHPC beams with steel fibers only showed a post cracking ductile behavior. The addition of little steel fiber volume (e.g. 0.5 %) to the plain UHPC beams enhanced the ductility. The enhancement at the ultimate capacity amounts to about 20 %. Meanwhile, the steel fibers with 0.9 % by volume showed much enhanced ductility and a maximum enhancement of the torsional carrying capacity up to 32 %. The addition of moderate steel fiber volume (e.g. 0.9 %) to one type of traditional reinforcement (either longitudinal or transverse) accomplished an effective post cracking torsional carrying mechanism. The steel fibers shows a tendency to replace the missing type of traditional reinforcement, however this should be confirmed by more tests and by using higher steel fiber volumes. A series of experimental tests on fiber reinforced UHPC prisms to investigate the post cracking shear strength and stiffness of the used UHPC mix (e.g. M3Q) was conducted. The results of these tests revealed that this fine grained UHPC mix has a weak post cracking shear behavior. The results of these tests were used later in the Finite Element (F.E) model. An analytical model based on the well known thin-walled tube analogy was developed in order to estimate the torsional carrying capacity of beams under pure torsion having different combinations of steel fibers and traditional reinforcement. The comparison between the test and model results showed very good agreement for all cases. A finite element model based on calibrated small scale tests was developed using ATENA F.E. package to predict the full load-deformation behavior of the test beams. The predictions of the model show very good agreement with the test results.