scholarly journals The application of composites (FRP) in military bridges

2013 ◽  
Vol 12 (2) ◽  
pp. 063-070
Author(s):  
Janusz Szelka ◽  
Zbigniew Kamyk
Keyword(s):  
Fatigue Tests ◽  
Light Weight ◽  
Bridge Span ◽  
Deck Plate ◽  
Composite Bridges ◽  
Military Bridge ◽  
Composite Bridge ◽  
Polyester Composites ◽  
American Concept

The needs of expeditionary forces involve the use of light-weight, short-span bridges so that their transport by air would be possible. A project which is currently developed in USA aims at the elaboration of a Composite Army Bridge (CAB) assault bridge and a Modular Composite Bridge – MCB logistic bridge. In 2004 CAB successfully underwent fatigue tests. A 14 m-long, all-composite treadway bridge span was loaded by using an MLC 100 vehicle and it withstood 20 000 load cycles. The MCB will be constructed by7 m of box modules and a 6.5 m access ramp. A 26 m-long and 4 m-wide bridge span is to provide the traffic ability of MLC 65. Furthermore, works on a 10 m-long, MLC 30 composite bridge are also developed in Canada too. The paper also presents the American concept of employing a deployable bridge system by utilising a composite structure. In order to formwork and reinforce the plate, fibre reinforced polyester composites (FRP) were used. The girder construction is made of aluminium pipes forming diamond truss with curved bottom chord. After they are integrated in the structure, the top chord nodes are connected through deck plate cast in-situ. The tests indicated that there exists the possibility of using polymer composites in military bridge construction and mobile structures of composite bridges.

Monitoring and Defect Detection of an All-Composite Road Bridge

2000 ◽  
Author(s):  
Roger M. Crane ◽  
John W. Gillespie ◽  
Dirk Heider ◽  
Douglas A. Eckel ◽  
Colin P. Ratcliffe
Keyword(s):  
Structural Integrity ◽  
Theoretical Calculations ◽  
Detection Algorithm ◽  
Mode Shapes ◽  
Manufacturing Defects ◽  
Vibration Data ◽  
Composite Bridges ◽  
Longitudinal Joint ◽  
Composite Bridge ◽  
Sandwich Core

Abstract This paper presents the results of an ongoing investigation into the use of broadband vibration data to monitor the structural integrity and health of an all-composite road bridge. Bridge 1-351 on Business Route 896 in Glasgow, Delaware, was replaced with one of the first state-owned all-composite bridges in the nation in the fall of 1998. The bridge consists of two E-Glass/vinyl ester sandwich core sections (13-ft × 32 ft) joined by a longitudinal joint in the traffic direction. Each sandwich core section consists of a 28-inch deep core and 0.4-0.7-inch thick facesheets. Vibration data were obtained from the upper and lower surfaces of the bridge using a mesh of 1050 test points. From the modal information and the visualization of the data, several aspects of the structural behavior of the bridge were obtained. These characteristics include the interactions between the bridge and abutments; the effectiveness of the longitudinal joint to couple the deck sections; the effectiveness of the core to couple the face sheets; and the structural integrity and dynamic consistency of the entire structure. Mode shapes and natural frequencies were determined and are correlated with theoretical calculations and vibration analyses conducted for this bridge. A novel algorithm using the vibration data is being developed that enables local perturbations sensitive to the state of the material (e.g. manufacturing defects, material degradation or service damage) to be detected and spatially located in the bridge. This technique has been successfully validated for locating damage in 1-D beam structures and is being extended to the 3-D sandwich configuration of the bridge. By coupling this damage detection algorithm with the more conventional modal technique, the quality assurance/quality control and health monitoring of large composite bridge can be obtained.

scholarly journals Strength Tests on Newly Fallen Snow

1969 ◽  
Vol 8 (54) ◽  
pp. 427-440 ◽  
Author(s):  
R. Perla
Keyword(s):  
Cone Penetrometer ◽  
Light Weight ◽  
Large Drop ◽  
Torque Wrench ◽  
Strength Tests ◽  
Order Of Magnitude ◽  
Magnitude Variation ◽  
A New Technique ◽  
Shear Frame

AbstractModified versions ofin situstrength tests previously applied to metamorphosed snow were developed to measure the mechanical properties of newly fallen snow during storm periods. A large drop-cone penetrometer, protected from the wind by an aluminum shell, was used to determine snow “hardness”. A lightweight model of the Haefeli ram penetrometer measured “ram numbers”. Shear strengths were obtained from large, light-weight frames. Some preliminary tests were made with a shear vane driven by a torque wrench. A new technique was devised for measuring tensile strength whereby a cantilever beam of snow is undercut until it fails under its own weight. Comparisons between the cantilever test and the shear-frame test show high ratios for tensile to shear strength. Cantilever strength plotted against density shows an order of magnitude variation in strength at all densities.

scholarly journals DESIGN OF PERKUWEN BRIDGE PART WAY LONG IKIS-LAMBAKAN PASER TANA PASER REGENCY PROVINCE EAST KALIMANTAN

CERUCUK ◽  
2019 ◽  
Vol 2 (1) ◽  
Author(s):  
Humaira Afrila ◽  
Markawie Markawie
Keyword(s):  
Design Method ◽  
Plate Thickness ◽  
Steel Structures ◽  
Structure Design ◽  
Steel Pipe ◽  
Pipe Pile ◽  
East Kalimantan ◽  
Composite Bridges ◽  
Composite Bridge ◽  
Steel Pipe Pile

Long Kali is a sub-district of Paser Tana Paser Regency Prov. East Kalimantan. In this sub-district have two village separate by a river, that is Perkuwen river, there is bridge has a broke. Whereas the village very needed a bridge because it is used as a transportation infrastructure for peoples and also passed by vehicles transporting oil palm yields . Therefore, the design of composite bridges made with spans 25 m and 7 m wide bridge.In this plan the analysis of Standard methods of loading refers to the bridge imposition For RSNI T-02-2005 about composite bridge structure design method, refers to RSNI T-03-2005 about Steel Structural Design For Bridge, SNI 03-1729-2002 about Steel Structures Planning Procedures and SNI 03-2847-2002 about Concrete Structures Calculation for Building.The result is used the main girder profile SH 950 x 400 x 16 x 32 and diaphragm WF 400 x 200 x 8 x 13. Vehicle floor plate thickness 20 cm using quality concrete  30 MPa and quality reinforcing steel reinforcement  360 MPa with subject dividers reinforcement D22- 100 and D12-100 mm. In using concrete pavement  30 MPa D22-100 mm staple reinforcement and shear reinforcement rebars quality D12-100 mm  360 MPa. Concrete abutment in the form  25 MPa at 2 m height and length of 8,5 m. Steel pipe pile foundations quality  25 MPa are 16 pieces with a length of 10 meters and a diameter of 0.4 m.Keyword: Bridge, composite, steel pipe pile.

Effect of PTFE Retainer on Friction Coefficient in Polymer Thrust Bearings under Dry Contact

2013 ◽  
Vol 683 ◽  
pp. 90-93 ◽  
Author(s):  
Koshiro Mizobe ◽  
Takashi Honda ◽  
Hitonobu Koike ◽  
Edson Costa Santos ◽  
Yuji Kashima ◽  
...  
Keyword(s):  
Friction Coefficient ◽  
Rolling Contact Fatigue ◽  
Contact Fatigue ◽  
Fatigue Tests ◽  
Rolling Contact ◽  
Low Friction ◽  
Friction Forces ◽  
Thrust Bearings ◽  
Dry Contact

Polyetheretherketone (PEEK) is a tough semi-crystalline thermoplastic polymer with excellent mechanical properties. While abilities of polyphenylenesulfide (PPS) are similar to PEEK, former material cost was lower than later. Polytetrafluoroethylene (PTFE) is well known because of its low friction coefficient and self lubrication ability. The objective of this study is to observe the friction coefficient of hybrid bearings, PTFE retainer sandwiched with PPS-races or PEEK-races. Rolling contact fatigue tests were performed and in situ friction forces wear measured. It is concluded that the PTFE retainer reduced friction coefficient.

Effect of In Situ TiB2 Particles on the Grain Size and Mechanical Properties of 7075 Aluminum Alloy

2021 ◽  
Vol 1035 ◽  
pp. 102-107
Author(s):  
Shao Ming Ma ◽  
Chuan Liu Wang ◽  
Yun Lin Fan
Keyword(s):  
Mechanical Properties ◽  
Grain Size ◽  
Aluminum Alloy ◽  
High Strength ◽  
Light Weight ◽  
7075 Aluminum Alloy ◽  
Directional Drilling ◽  
High Strength Aluminum Alloy ◽  
Drill Pipes

Light-weight and high-strength aluminum alloy drill pipes are potential and promising to replace traditional steel drill pipes. In this study, the grain size and mechanical properties of aluminum alloy drilling pipe materials reinforced by in-situ TiB2 particles were studied. The results showed when reinforced by in-situ TiB2 particles the grain size of aluminum alloy materials was refined from 155 m to 57 m and ultimate tensile strength was increased from 590 MPa to 720 MPa. Besides, the results also indicated that the friction coefficient was reduced from 0.99 to 0.50 and thus the abrasion resistance of 7075 aluminum alloy was enhanced by 34 %. This study provided theoretical basis for the application of light-weight and high-strength aluminum alloy drill pipes in directional drilling and ultra-deep wells.

Effects of Water Jet Peening and Hardening Treatment on Fatigue Properties of SCr420

2009 ◽  
Author(s):  
Akira Shimamoto ◽  
Ryo Kubota ◽  
Sung-mo Yang ◽  
Dae-kue Choi ◽  
Weiping Jia
Keyword(s):  
Fatigue Life ◽  
High Speed ◽  
Fatigue Crack Initiation ◽  
Fatigue Tests ◽  
Water Jet ◽  
Fatigue Properties ◽  
In Situ Observation ◽  
Axial Tensile ◽  
High Pressure Water Jet

An experimental study of high pressure water jet peening treatment on chromium steal SCr420 H3V2L2 is conducted to study the effects of cavitation impacts of high-speed water on fatigue crack initiation and propagation of notched specimens. There are six different kinds of specimens. First three kinds are treated with; only annealing, only water quenching, and only oil quenching. Other three kinds are treated with above heat treatment and water jet peening, respectively. An axial tensile fatigue tests’ condition is 260MPa maximum stress amplitude, 0 stress ratio and 10Hz frequency, while in-situ observation by SEM is employed. Although fatigue life of the specimens with annealing and water jet peening is shorter than that of only annealing, fatigue life of water and oil quenching with water jet peening specimens is obviously longer than those without water jet peening treatment. Water jet peening has increased residual stress inside the specimens on the latter case and raised their fatigue strength. In-situ observation on the crack tips approves above analysis.

scholarly journals Fatigue resistant jaw muscles facilitate long-lasting courtship behaviour in the southern alligator lizard ( Elgaria multicarinata )

2020 ◽  
Vol 287 (1935) ◽  
pp. 20201578
Author(s):  
Allyn Nguyen ◽  
Jordan P. Balaban ◽  
Emanuel Azizi ◽  
Robert J. Talmadge ◽  
A. Kristopher Lappin
Keyword(s):  
Muscle Function ◽  
Fatigue Tests ◽  
Courtship Behaviour ◽  
Muscle Properties ◽  
Jaw Muscles ◽  
Adductor Muscles ◽  
Extreme Performance ◽  
Alligator Lizard

The southern alligator lizard ( Elgaria multicarinata ) exhibits a courtship behaviour during which the male firmly grips the female's head in his jaws for many hours at a time. This extreme behaviour counters the conventional wisdom that reptilian muscle is incapable of powering high-endurance behaviours. We conducted in situ experiments in which the jaw-adductor muscles of lizards were stimulated directly while bite force was measured simultaneously. Fatigue tests were performed by stimulating the muscles with a series of tetanic trains. Our results show that a substantial sustained force gradually develops during the fatigue test. This sustained force persists after peak tetanic forces have declined to a fraction of their initial magnitude. The observed sustained force during in situ fatigue tests is consistent with the courtship behaviour of these lizards and probably reflects physiological specialization. The results of molecular analysis reveal that the jaw muscles contain masticatory and tonic myosin fibres. We propose that the presence of tonic fibres may explain the unusual sustained force properties during mate-holding behaviour. The characterization of muscle properties that facilitate extreme performance during specialized behaviours may reveal general mechanisms of muscle function, especially when done in light of convergently evolved systems exhibiting similar performance characteristics.

scholarly journals In Situ and Post-Mortem Characterizations of Ultrasonic Spot Welded AZ31B and Coated Dual Phase 590 Steel Joints

Metals ◽  
2020 ◽  
Vol 10 (7) ◽  
pp. 899 ◽  
Author(s):  
Jian Chen ◽  
Yong Chae Lim ◽  
Donovan Leonard ◽  
Hui Huang ◽  
Zhili Feng ◽  
...  
Keyword(s):  
High Speed ◽  
Tensile Tests ◽  
Fatigue Tests ◽  
Image Correlation ◽  
Joint Interface ◽  
Welding Time ◽  
Cross Sectional ◽  
Welding Condition ◽  
Lap Shear

Ultrasonic spot welding using different welding conditions was applied to join dissimilar metals of galvanized DP590 steel and AZ31B magnesium sheets. In situ high-speed imaging, digital image correlation, and infrared thermography were utilized to quantitatively study the interfacial relative motion, surface indentation, and heat generation across the joint faying interface and the sheet/sonotrode interfaces under the welding condition of moderate welding power and short welding time. For welds made with high power and long welding time, lap shear tensile tests as well as fatigue tests were carried out. Different fracture modes were observed after the lap shear tensile tests and fatigue tests performed under different peak loads. Post-weld cross-sectional analysis with scanning electron microscopy coupled with energy dispersive X-Ray spectroscopy revealed the variation of morphology and chemical composition at the joint interface for welds made with different welding conditions.

Pressureless Melt Infiltrated Non-Oxide Ceramic-Metal Composites

2008 ◽  
Vol 403 ◽  
pp. 251-252
Author(s):  
A. Kalemtas ◽  
Gürsoy Arslan ◽  
Ferhat Kara
Keyword(s):  
Oxide Ceramic ◽  
Light Weight ◽  
X Ray Diffraction ◽  
Infiltration Process ◽  
Metal Composites ◽  
X Ray ◽  
Melt Infiltration ◽  
In Situ Reactions ◽  
B4c Powder

In the present study highly dense (open porosity < 1 %), light-weight (d £ 2.85 g/cm3) and Al4C3-free non-oxide ceramic-metal composites were produced at comparatively low temperatures ( 1250°C) by pressurless melt infiltration. Phase analysis of the SiC-B4C-Al composites revealed that a significant amount of hygroscopic Al4SiC4 and Al4C3 phases were formed. Si3N4 powder was added in different amounts to the SiC-B4C powder batches to suppress formation of these phases via in-situ reactions during the infiltration process. X-ray diffraction results of the SiC-B4C-Si3N4-Al composites confirmed that the incorporation of Si3N4 to the SiC-B4C system reduced or eliminated the formation of the hygroscopic phases and resulted in in-situ formation of AlN, SiC and Si phases in the composite.

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