Elasto-Plastic Impact Analysis on RC Beams with Statically Bending Failure Mode.

A bolt-connected precast reinforced concrete deep beam (RDB) is proposed as a lateral resisting component that can be used in frame structures to resist seismic loads. RDB can be installed in the steel frame by connecting to the frame beam with only high-strength bolts, which is different from the commonly used cast-in-place RC walls. Two 1/3 scaled specimens with different height-to-length ratios were tested to obtain their seismic performance. The finite element method is used to model the seismic behavior of the test specimens, and parametric analyses are conducted to study the effect on the height-to-length ratio, the strength of the concrete and the height-to-thickness ratio of RDBs. The experimental and numerical results show that the RDB with a low height-to-length ratio exhibited a shear–bending failure mode, while the RDB with a high height-to-length ratio failed with a shear-dominated failure mode. By comparing the RDB with a height-to-length ratio of 2.0, the ultimate capacity, initial stiffness and ductility of the RDB with a height-to-length ratio of 0.75 increased by 277%, 429% and 141%, respectively. It was found that the seismic performance of frame structures could be effectively adjusted by changing the height-to-length ratio and length-to-thickness of the RDB. The RDB is a desirable lateral-resisting component for existing and new frame buildings.

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Assesment of Main Models for Predicting Debonding Load-Bearing Capacity against Intermediate Crack-Induced Debonding Failure in FRP-Strengthened RC Beams

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.311-313.1941 ◽

2011 ◽

Vol 311-313 ◽

pp. 1941-1944

Author(s):

Gui Bing Li ◽

Yu Gang Guo ◽

Xiao Yan Sun

Keyword(s):

Bearing Capacity ◽

Failure Mode ◽

Failure Modes ◽

Rc Beams ◽

Test Results ◽

Load Bearing Capacity ◽

Load Bearing ◽

Accuracy Test ◽

New Models ◽

Debonding Load

intermediate crack-induced debondingis one of the most dominant failure modes in FRP-strengthened RC beams. Different code models and provisions have been proposed to mitigateintermediate crack-induced debondingfailure.However, these models and provisions can not mitigate this failure mode effectively. Recnetly, new models have been proposed to solve this problem. Out of all the existing models, four typical ones are investigated in the current study. A comprehensivecomparison among these models is carried out in order to evaluate their performance and accuracy. Test results ofﬂexural specimens with intermediate crack-induced debonding failurecollected from the existing literature are used in the current comparison. The effectivenessand accuracy of each model have been evaluated based on these experimental results. It is shown that the current modals are all conservative and inadequite to effectively mitigate intermediate crack-induced debonding in flexurally strengthened members.

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Failure mode transitions in RC beams: A cohesive/overlapping crack model application

Meccanica ◽

10.1007/s11012-013-9753-4 ◽

2013 ◽

Vol 48 (10) ◽

pp. 2349-2366 ◽

Cited By ~ 1

Author(s):

A. Carpinteri ◽

M. El-Khatieb ◽

E. Cadamuro

Keyword(s):

Failure Mode ◽

Crack Model ◽

Rc Beams ◽

Model Application ◽

Mode Transitions

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Bending properties of three-dimensional honeycomb sandwich structure composites: experiment and Finite Element Method simulation

Textile Research Journal ◽

10.1177/0040517517703602 ◽

2017 ◽

Vol 88 (17) ◽

pp. 2024-2031 ◽

Cited By ~ 5

Author(s):

Lihua Lv ◽

Yaoli Huang ◽

Jingrui Cui ◽

Yongfang Qian ◽

Fang Ye ◽

...

Keyword(s):

Failure Mode ◽

Cross Section ◽

Sandwich Structure ◽

Three Dimensional ◽

Finite Element Method Simulation ◽

Cross Section Shape ◽

Section Shape ◽

Honeycomb Sandwich ◽

Bending Failure ◽

Honeycomb Sandwich Structure

This paper fabricated three-dimensional (3D) honeycomb sandwich structure fabrics with three different cross-section shapes on an ordinary loom by reasonable design with low cost. The 3D honeycomb sandwich structure composites were fabricated by the vacuum assisted resin transfer molding process. Then, the bending properties of 3D honeycomb sandwich structure composites with different cross-section shapes were tested. The results showed that the 3D honeycomb sandwich structure composite with a hexagonal cross-section shape had the maximum load, the 3D honeycomb sandwich structure composite with a triquetrous cross-section shape had the minimum load and the 3D honeycomb sandwich structure composite with a quadrangular cross-section shape had a load between the two. The bending failure mode showed that the 3D honeycomb sandwich structure composite had a typical bending failure mode with compression failure in the front and tensile failure in the back. Finally, the load–displacement curves and failure mode were obtained by FEM (Finite Element Method) simulation with ABAQUS software. The good agreements of comparisons proved the validity of the FEM.

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An Experimental Study on Load Carring Behavior and Prediction of Failure Mode for Flexural Strengthened RC Beams with FRP Sheet.

Doboku Gakkai Ronbunshu ◽

10.2208/jscej.2002.711_91 ◽

2002 ◽

pp. 91-109

Author(s):

Norimitsu KISHI ◽

Hiroshi MIKAMI ◽

Yusuke KURIHASHI

Keyword(s):

Experimental Study ◽

Failure Mode ◽

Rc Beams ◽

Frp Sheet

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Implication of Unbondedness in Reinforced Concrete Beams

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.587.36 ◽

2012 ◽

Vol 587 ◽

pp. 36-41 ◽

Cited By ~ 1

Author(s):

S.F.A. Rafeeqi ◽

S.U. Khan ◽

N.S. Zafar ◽

T. Ayub

Keyword(s):

Shear Strength ◽

Reinforced Concrete ◽

Failure Mode ◽

Shear Failure ◽

Concrete Beams ◽

Experimental Results ◽

Reinforced Concrete Beams ◽

Rc Beams ◽

Flexural Capacity ◽

Flexural Reinforcement

In this paper, behaviour of nine (09) RC beams (including two control beams) after unbonding and exposing flexural reinforcement has been studied which were intentionally designed and detailed to observe flexural and shear failure. Beams have been divided into three groups based on failure mode and unbounded and exposed reinforcement. Beams have been tested under two-point loading up to failure. Experimental results are compared in terms of beam behaviour with respect to flexural capacity and failure mode which revealed that the exposed reinforcement does not altered flexural capacity significantly and unbondedness positively influences shear strength; however, serviceability performance of beams with unbonded and exposed reinforcement is less.

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EMPIRICAL SHEAR BASED MODEL FOR PREDICTING PLATE END DEBONDING IN FRP STRENGTHENED RC BEAMS

Journal of Civil Engineering and Management ◽

10.3846/jcem.2021.14304 ◽

2021 ◽

Vol 27 (2) ◽

pp. 117-138

Author(s):

Ahmed K. El-Sayed ◽

Mohammed A. Al-Saawani ◽

Abdulaziz I. Al-Negheimish

Keyword(s):

Shear Strength ◽

Reinforced Concrete ◽

Failure Mode ◽

Fiber Reinforced Polymers ◽

Simplified Model ◽

Rc Beams ◽

Shear Cracks ◽

Reinforced Polymers ◽

Experimental Database ◽

Proposed Model

This paper presents the development of a simplified model for predicting plate end (PE) debonding capacity of reinforced concrete (RC) beams flexurally strengthened using fiber reinforced polymers (FRP). The proposed model is based on the concrete shear strength of the beams considering main parameters known to affect the opening of the shear cracks and consequently affect PE debonding. The model considers also the effect of the location of the cut-off point of FRP plate along the span of the beam. The proposed model was verified against experimental database of 128 FRP-strengthened beams collected from previous studies that failed in PE debonding. In addition, the predictions of the proposed model were also compared with those of the existing PE debonding models. The predictions of the model were found to be comparable to the best predictions provided by the existing models, yet the proposed model is simpler. Furthermore, the proposed model was combined with the ACI 440 IC debonding equation to provide a procedure for predicting the governing debonding failure mode in FRP strengthened RC beams. The procedure was validated against 238 beam tests available in the literature, and shown to be a reliable approach.

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Modeling of CFRP strengthened RC beams using the SNSM technique, proposed as an alternative to NSM and EBR techniques

Frattura ed Integrità Strutturale ◽

10.3221/igf-esis.54.02 ◽

2020 ◽

Vol 14 (54) ◽

pp. 21-35

Author(s):

Adel Boulebd ◽

Ferhoune Noureddine ◽

Boukhezar Mohcene ◽

Habib Abdelhak Mesbah

Keyword(s):

Finite Element ◽

Failure Mode ◽

Numerical Study ◽

Concrete Cover ◽

Rc Beams ◽

Near Surface ◽

Externally Bonded ◽

Bending Capacity ◽

Near Surface Mounted ◽

Abaqus Software

In this paper, an analytical and numerical study in FEM finite element by the ABAQUS software was conducted. Which aims to study the behaviour of RC beams bending strengthened with SNSM side near surface mounted technique, proposed as a solution to avoid the failure mode by debonding of the strengthening, the disadvantage of the EBR externally bonded reinforced technique, and the failure mode by separation of the concrete cover relative to the NSM near surface mounted technique, by comparing the behaviour of the three techniques, the effect of the quantity of strengthening and confirm the results with the literature. The results of this study show that the numerical and analytical model can predict the behaviour of strengthened RC beams according to the three techniques, a clear improvement of the bending capacity of beams strengthened is noticed. A good preservation of the ductility of SNSM beams with a better failure mode.

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Risk Assessment of Ship Systems Based on Forward FTF Method

Volume 3: Structures, Safety, and Reliability ◽

10.1115/omae2019-95320 ◽

2019 ◽

Author(s):

Songyan Mai ◽

Ji Zeng ◽

Qi Feng ◽

Renan Liu ◽

Yan Chen

Keyword(s):

Failure Mode ◽

Impact Analysis ◽

Fault Tree Analysis ◽

Maintenance Management ◽

Mode Effects ◽

Operation And Maintenance ◽

Criticality Analysis ◽

Ship Operation ◽

Different Levels ◽

Classification Society

Abstract Ocean-going vessels sailing alone in the boundless sea often encounter various problems and pose a serious threat to the safety of the ship. According to statistic, many of these accidents are caused by problems such as aging equipment and lack of maintenance. After IMO issued mandatory regulations, China Classification Society (CCS) released Failure Mode and Impact Analysis Guide in 2017 (Guidance Notes GD16-2017), in connection with failure mode and impact analysis for ship equipment and systems. In this paper, based on a multi-purpose offshore carrier, the forward FTF (FMECA & FTA) method is adopted. The failure mode, effects and criticality analysis (FMECA) is conducted for the study on failure mode of ship system, including failure rate, cause and effect (probability and severity). Fault tree analysis (FTA) is to calculate and assess the risk of the ship system. Based on the forward FTF principle, Smart Captain, an operation and maintenance management system was developed for this ship. The system can identify the faults of the ship system and carry out different levels of alarms automatically, then a corresponding maintenance and operation instructions according to the equipment manual is given. By using Smart Captain, the crew member can carry out ship operation and maintenance efficiently safely.

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