Delamination behavior analysis of steel/polymer/steel high-strength laminated sheets in a V-die bending test

Automated fiber placement (AFP) has been widely used as an advanced manufacturing technology for large and complex composite parts and the trajectory planning of the laying path is the primary task of AFP technology. Proposed in this paper is an experimental study on the effect of several different path planning placements on the mechanical behavior of laminated materials. The prepreg selected for the experiment was high-strength toughened epoxy resin T300 carbon fiber prepreg UH3033-150. The composite laminates with variable angles were prepared by an eight-tow seven-axis linkage laying machine. After the curing process, the composite laminates were conducted by tensile and bending test separately. The test results show that there exists an optimal planning path among these for which the tensile strength of the laminated specimens decreases slightly by only 3.889%, while the bending strength increases greatly by 16.68%. It can be found that for the specific planning path placement, the bending strength of the composite laminates is significantly improved regardless of the little difference in tensile strength, which shows the importance of path planning and this may be used as a guideline for future AFP process.

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Crystal Phase Formation and Mechanical Properties of Lithium Disilicate Glass-Ceramics for Dental Restoration

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.177.447 ◽

2010 ◽

Vol 177 ◽

pp. 447-450 ◽

Cited By ~ 1

Author(s):

Xin Zhang ◽

Yi Wen Hu ◽

Yin Wu ◽

Wen Jie Si

Keyword(s):

Mechanical Properties ◽

Phase Formation ◽

Glass Ceramics ◽

High Strength ◽

Lithium Disilicate ◽

Sem Analysis ◽

Dental Restoration ◽

Bending Test ◽

Crystal Phase ◽

High Temperature Xrd

The purpose of this study was to evaluate the crystal phase formation behavior and its influence on the mechanical properties of LiO2-SiO2-P2O5 glass-ceramics system. High temperature XRD was used to analyze the crystal phase formation in situ. The crystalline phases in the material both before and after heat-treatment were also analyzed. The flexural strength was measured by three-point bending test according to ISO 6872:2008(E). The SEM analysis showed that the high strength of the glass-ceramics is attributed to the continuous interlocking microstructure with fine lithium disilicate crystallines.

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Investigation of Mechanical Properties of Nano Sized Clay/LDH Particle as Hybrid Nano Composite Material

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.766-767.355 ◽

2015 ◽

Vol 766-767 ◽

pp. 355-361

Author(s):

S. Sivasaravanan ◽

V.K. Bupesh Raja ◽

S. Prabhu ◽

S. Dineshkumar ◽

Gokulaprasad

Keyword(s):

Composite Material ◽

Testing Machine ◽

Weight Ratio ◽

High Strength ◽

Sem Analysis ◽

Bending Test ◽

Flexural Property ◽

Weight Percentage ◽

Three Point Bending ◽

Sonication Technique

Usage of Hybrid nanocomposite materials provides a greater opportunity to replace the conventional materials due to their properties such as light weight and high strength to based on weight ratio. In this synergitic study, nanosized clay particle and layered double hydroxide particles are used. nanoclay and LDH particles were mixed on the bases of weight percentage (1wt% to 5wt%) by ultra sonication technique. The composite material was fabricated by one of the most common method known as hand lay-up technique. The composite materials was prepared in the form of plate with 4mm of thickness.The characterization of tensile and flexural property of the nanoclay, LDH and combination of both was analysis by tensile test using universal testing machine and three point bending test respectively. The tensile and three point bending test specimens were cut to size as per ASTM standard.The morphology of composite was studied using SEM analysis.

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An Experimental Evaluation of Energy Absorption of TRIP Steel by Small Punch Test

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.725.60 ◽

2016 ◽

Vol 725 ◽

pp. 60-65

Author(s):

Asuka Hayashi ◽

Takeshi Iwamoto

Keyword(s):

Energy Absorption ◽

Trip Steel ◽

Dynamic Condition ◽

High Strength ◽

High Energy ◽

Bending Test ◽

Absorption Characteristic ◽

Small Punch ◽

Three Point Bending ◽

Punch Test

TRIP steel possesses high strength and excellent ductility. In addition, it is possible that TRIP steel indicates high energy absorption so that TRIP steel is expected to apply to automotive members. To design the members made of TRIP steel, it is important to clarify its energy absorption characteristic at various deformation rates. In the previous study, the energy absorption characteristic of TRIP steel is evaluated by J-integral under quasi-static to dynamic condition by using a thick specimen based on ASTM standard. However, by using such thick specimens, it is difficult to conduct the three-point bending test under impact condition because of high ductility in TRIP steel. A small punch (SP) test is the experimental method which can evaluate fracture parameters such as J-integral. By using a conventional use of small specimen in the SP test, it is possible to evaluate J-integral of TRIP steel under impact deformation. In this study, energy absorption characteristic of TRIP steel is investigated by SP test under different deflection rates. Then, the relationship between the values of J-integral obtained by previously conducted three-point bending test and the SP test of TRIP steel is discussed.

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Construction Technology Research of RC Beams Strengthened with Prestressed CFRP Plates

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.268-270.659 ◽

2011 ◽

Vol 268-270 ◽

pp. 659-663

Author(s):

Hua Chen ◽

Kan Kang ◽

Lang Ni Deng

Keyword(s):

Crack Resistance ◽

Concrete Beams ◽

High Strength ◽

The Self ◽

Bending Test ◽

Construction Technology ◽

Rc Beams ◽

Test Results ◽

Technology Research ◽

Flexural Capacity

The method of applying prestress to CFRP plates can make full use of the characteristics of high-strength, enhance the force properties, prevent peeling damage and reduce the strain lag. Construction technology of prestressed CFRP plates strengthening reinforcement concrete beams was introduce in this paper, and bending test of 6 reinforcement concrete beams strengthened with prestressed CFRP plates were carried out based on the self-developed prestressed CFRP plates supporting anchorages. The test results indicate that the flexural capacity and crack resistance capacity can be increased compared with non-prestressed CFRP plates, and the construction technology can be adopted in practical projects.

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C-section Cold-Formed Steel as Structural Members in Housing Construction in the Philippines

IABSE Congress, New York, New York 2019: The Evolving Metropolis ◽

10.2749/newyork.2019.0235 ◽

2019 ◽

Author(s):

Bernardo A. Lejano

Keyword(s):

Axial Compression ◽

High Speed ◽

Failure Modes ◽

Weight Ratio ◽

High Strength ◽

The Philippines ◽

Bending Test ◽

Housing Construction ◽

Distortional Buckling ◽

Cold Formed Steel

<p>Getting good lumber for housing construction is becoming difficult in the Philippines due to existing partial log ban. Although, the use of reinforced concrete is still the most popular in construction, an emerging alternative is the use of cold-formed steel (CFS). It is gaining popularity because of its high strength-to- weight ratio. However, information about the structural performance of locally-produced cold-formed steel is almost nonexistent. Although, design provisions are stipulated in the local Code, these are based on formulas developed abroad, hence the need to investigate these cold-formed steel. This study focuses on the C-section cold-formed steel, which is the most popularly used. The objective is to verify its performance when subjected to axial compression and flexure, both experimentally and computationally. For the computational part, the formulas stipulated in the National Structural Code of the Philippines were followed. For the experimental part, the cold-formed steel members were subjected to compression loads and flexural loads. Aside from usual sensors, high-speed cameras were used to capture the failure modes. For axial compression test, 80 specimens with different lengths and thicknesses were tested. For flexure, 24 specimens of back-to-back C-sections were subjected to 4-point bending test. Results showed the predicted strengths were well below the experimental values. In design, this means the use of Code-based formulas is conservative. Failure modes observed were torsional buckling and distortional buckling. Comparison of failure modes between experiment and computation shows 70% agreement for compression and 75% for flexure. Finite element method calculations were also done and were compared with experimental results.</p>

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The First L555 (X80) Pipeline in Japan

Volume 3: Materials and Joining ◽

10.1115/ipc2012-90105 ◽

2012 ◽

Author(s):

Yoshiyuki Matsuhiro ◽

Noritake Oguchi ◽

Toshio Kurumura ◽

Masahiko Hamada ◽

Nobuaki Takahashi ◽

...

Keyword(s):

Gas Metal Arc Welding ◽

Control Process ◽

High Strength ◽

Longitudinal Direction ◽

Full Scale ◽

Ground Movement ◽

Bending Test ◽

Metal Arc Welding ◽

S Curve ◽

Girth Welds

The construction of the first L555(X80) pipeline in Japan was completed in autumn, 2011.In this paper, the overview of the design consideration of the line, technical points for linepipe material and for girth welds are presented. In recent years the use of high strength linepipe has substantially reduced the cost of pipeline installation for the transportation of natural gas. The grades up to L555(X80) have been used worldwide and higher ones, L690(X100) and L830(X120), e.g., are being studied intensively. In the areas with possible ground movement, the active seismic regions, e.g., pipeline is designed to tolerate the anticipated deformation in longitudinal direction. In Japan, where seismic events including liquefaction are not infrequent, the codes for pipeline are generally for the grades up to L450(X65). Tokyo Gas Co. had extensively investigated technical issues for L555(X80) in the region described above and performed many experiments including full-scale burst test, full-scale bending test, FE analysis on the girth weld, etc., when the company concluded the said grade as applicable and decided project-specific requirements for linepipe material and for girth weld. Sumitomo Metals, in charge of pipe manufacturing, to fulfill these requirements, especially the requirement of round-house type stress-strain (S-S) curve to be maintained after being heated by coating operation, which is critical to avoid the concentration of longitudinal deformation, developed and applied specially designed chemical composition and optimized TMCP (Thermo-Machanical Control Process) and supplied linepipe (24″OD,14.5∼18.9mmWT) with sufficient quality. It had also developed and supplied induction bends needed with the same grade. Girth welds were conducted by Sumitomo Metal Pipeline and Piping, Ltd and mechanized GMAW (Gas Metal Arc Welding) was selected to achieve the special requirements, i.e., the strength of weld metal to completely overmatch the pipe avoiding the concentration of longitudinal strain to the girth weld, and the hardness to be max.300HV10 avoiding HSC (Hydrogen Stress Cracking) on this portion. Both of RT (Radiographic Test) and UT (Ultrasonic Test) were carried out to all the girth welds. These were by JIS (Japan Industrial Standards) and the project-specific requirements.

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Experimental Evaluation of the Influence of Aggregate Strength on the Flexural Cracking Behavior of Epoxy Asphalt Mixtures

Materials ◽

10.3390/ma13081876 ◽

2020 ◽

Vol 13 (8) ◽

pp. 1876

Author(s):

Wei Xu ◽

Xiaoshu Wei ◽

Jintao Wei ◽

Zhengxiong Chen

Keyword(s):

Asphalt Concrete ◽

High Strength ◽

Bending Test ◽

Steel Bridge ◽

Test Results ◽

Cracking Resistance ◽

Cracking Behavior ◽

Epoxy Asphalt ◽

Fracture Area ◽

Aggregate Strength

The flexural cracking resistance of an asphalt concrete mixture used in a steel bridge deck pavement needs to be higher than that of one used in ordinary pavement. In this study, mechanical experimental tests were used to evaluate the influence of the aggregate strength on the flexural cracking behavior of epoxy asphalt concrete (EAC). The aggregate fracture area of beam cross sections was quantitatively analyzed by digital image processing, and crack propagation in the mixture was analyzed using fracture mechanics theory. The bending test results showed that the EAC containing high-strength aggregates exhibited the highest flexural cracking resistance among all of the aggregate mixtures under the same conditions. The use of high-strength aggregates led to a reduction in the aggregate fracture area, thereby improving the flexural cracking resistance of the mixture. The aggregate strength had a significant influence on the flexural cracking propagation behavior of the mixture. Fatigue test results at strain-controlled levels of 600–1200 με and 15 °C showed that the aggregate strength had no evident influence on the fatigue properties of the EAC. It is recommended that high-strength aggregates are used to increase the fracture resistance of aggregates and the flexural crack resistance of EACs.

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J Integral of Steel Fiber Reinforced High Strength Concrete

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.476-478.1568 ◽

2012 ◽

Vol 476-478 ◽

pp. 1568-1571

Author(s):

Ting Yi Zhang ◽

Guang He Zheng ◽

Ping Wang ◽

Kai Zhang ◽

Huai Sen Cai

Keyword(s):

High Strength Concrete ◽

Fiber Volume Fraction ◽

Steel Fiber ◽

Volume Fraction ◽

High Strength ◽

Bending Test ◽

Fiber Reinforced ◽

Fiber Volume ◽

Three Point Bending ◽

Strength Concrete

Through the three-point bending test on the specimens of steel fiber reinforced high strength concrete (SFHSC), the effects of influencing factors including water-cement ratio (W/C) and the fiber volume fraction (ρf) upon the critical value(JC) of J integral were studied. The results show that the variation tendencies of JC are different under different factors. JC meets the linear statistical relation with W/C, ρf, respectively.

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