Bond performance of rubber particles in the self-compacting concrete

Generating more ductile concrete elements by using waste tire rubbers have been studied for thirty years. Researchers have been produced a lot of rubberized concrete from low strength structure applications to self-compacting concretes having high strength and durability. It is possible to have more flexible concrete while using the fiber shaped waste tire rubbers. Critical problem of use of these rubbers is poor adherence between rubbers and cement paste interface. It is assumed that use of pozzolans with the Portland cement will fix this adherence problem. Therefore, waste tire rubbers have been studied in the self-compacting concrete in order to enhance the problem. Portland cement, grand granulated furnace slag and pozzolanic cement were used together for preparing the self-compacting concretes. Bonding performances of waste tire rubbers and reinforced bars in the self-compacting rubberized concrete were investigated experimentally in this study

Bond Performance of the Rubber particles in the Self-Compacting Concrete

Generating more ductile concrete elements by using waste tire rubbers have been studied for thirty years. Researchers have been produced a lot of rubberized concrete from low strength structure applications to self-compacting concretes having high strength and durability. It is possible to have more flexible concrete while using the fiber shaped waste tire rubbers. Critical problem of use of these rubbers is poor adherence between rubbers and cement paste interface. It is assumed that use of pozzolans with the Portland cement will fix this adherence problem. Therefore, waste tire rubbers have been studied in the self-compacting concrete in order to enhance the problem. Portland cement, grand granulated furnace slag and pozzolanic cement were used together for preparing the self-compacting concretes. Bonding performances of waste tire rubbers and reinforced bars in the self-compacting rubberized concrete were investigated experimentally in this study

AN INVESTIGATION ON ITZ MICROSTRUCTURE OF THE CONCRETE CONTAINING WASTE VEHICLE TIRE

Interfacial transition zone (ITZ) microstructure o[ rubber reinforced concrete has been examined hy using Scanning Electron Microscopy (SEM). The ruhber reinforced concrete has been prepared in the form consisting of various proportions of waste veh ide tires. The effect of the rubber on interfacial transition zone which exists between tire ruhber and cement paste has been investigated. A total of () batches of concretes has been prepared. Each batches consists of six cylinders which makes totally finy four samples of '/>J50x300 111m. Compressive strength, split tensile strength, unit weight tests and SEM analysis were conducted on the prepared samples. In this particular study, bonding characteristic and fracture analysis between rubher tires and cement paste have been investigated. Although adhesion hetween the rubber and cement paste was weak, roughening interface is formed and it constructed a mechanical interlock

A study on dynamic modulus of self-consolidating rubberized concrete

In this study, dynamic modulus of elasticity of self-consolidating rubberized concrete is evaluated by using results of ultrasonic pulse velocity and resonance frequency tests. Additionally, correlation between dynamic modulus of elasticity and compressive strength results is compared. For evaluating the dynamic modulus of elasticity of self-consolidating rubberized concrete, prismatic specimens having 100 x 100 x 500 mm dimensions are prepared. Dynamic modulus of elasticity values obtained by non-destructive measurements techniques are well agreed with those given in the literature

Wear behavior of boron-doped Ni\u3csub\u3e3\u3c/sub\u3eAl material at elevated temperature

The wear behavior of boron-doped Ni Al intermetallic compound was investigated at ambient and elevated temperatures. The Ni Al + B wear samples were prepared by cutting from a 1-mm thick rolled sheet material. Wear tests were carried out on a general purpose wear testing machine having a heating unit and block-disc sample configuration. The counterface material was prepared from 100Cr steel. The tests were carried out at temperatures of 25, 100, 300 and 450°C. The effects of load and temperatures on the weight loss of Ni Al + B were determined by using some characterization methods such as scanning electron microscopy (SEM), energy dispersive spectroscopy (EDS) and XRD analysis. The variations of weight loss versus test temperature show a slight decrease in the weight loss except in the case of 50 and 75 N loadings and temperature of 100°C. The weight loss values of the tests at the room temperature increase with load. At 100°C, the weight losses were about 10-15 times higher than weight loss values in the experiments done at RT. Further, the weight losses reached to the maximum level at 100°C compared to the tests done at the higher temperatures 300 and 450°C. The results were similar to each other and lower than those done at other temperatures. The changes on the microhardness and friction coefficient versus test temperature are well agreed with the variations of the weight loss and test temperature. The wear surface examinations and observations suggest that the dominant wear mechanism is an oxidational wear. The type and physical characteristics of the oxide layers produced on the surfaces contribute to the wear resistance as well as contribution of unique characteristics, such as high temperature, hardness and strength of Ni Al + B. © 2004 Published by Elsevier B.V. 3 3 6 3

Effect of various atmospheres on the threshold fatigue crack growth behavior of AISI 304 stainless steel

The threshold fatigue crack growth (FCG) behavior of AISI 304 austenitic stainless steel was investigated under three different atmospheres: dry argon, hydrogen and moist air. FCG tests were performed with an MTS 810 servohydroulic machine on compact tension specimens and crack closure measurements were done with an extensometer. A Plexiglass environmental chamber was built to control the atmosphere. Ferrofluid tests were applied to determine the transformed martensitic structure. The results of tests done under the three different atmospheres showed that the material is sensitive to the hydrogen atmosphere. Partial intergranular and transgranular fracture was observed at the fracture surface of the material tested under argon. However, the nature of the fracture was only transgranular under both hydrogen and moist air. Hydrogen degradation was attributed to hydrogen embrittlement and the material did not show threshold behavior at the near-threshold region. Comparison of results obtained in argon and moist air showed that the latter slightly influenced the crack growth rate

A study on dynamic modulus of self-consolidating rubberized concrete

Emiroglu, Mehmet/0000-0002-0214-4986WOS: 000358476400005In this study, dynamic modulus of elasticity of self-consolidating rubberized concrete is evaluated by using results of ultrasonic pulse velocity and resonance frequency tests. Additionally, correlation between dynamic modulus of elasticity and compressive strength results is compared. For evaluating the dynamic modulus of elasticity of self-consolidating rubberized concrete, prismatic specimens having 100 x 100 x 500 mm dimensions are prepared. Dynamic modulus of elasticity values obtained by non-destructive measurements techniques are well agreed with those given in the literature.Scientific Research Projects Management Council of the Firat University of TurkeyFirat University [1933]The research described in this paper was financially supported by the Scientific Research Projects Management Council of the Firat University of Turkey (Project no. 1933)

Torsional Behaviour and Finite Element Analysis of the Hybrid Laminated Composite Shafts: Comparison of VARTM with Vacuum Bagging Manufacturing Method

Braided sleeve composite shafts are produced and their torsional behavior is investigated. The braided sleeves are slid over an Al tube to create very strong and rigid tubular form shafts and they are in the form of 2/2 twill biaxial fiber fabric that has been woven into a continuous sleeve. Carbon and glass fibers braided sleeves are used for the fabrication of the composite shafts. VARTM (vacuum assisted resin transfer molding) and Vacuum Bagging are the two different types of manufacturing methods used in the study. Torsional behaviors of the shafts are investigated experimentally in terms of fabrication methods and various composite materials parameters such as fiber types, layer thickness, and ply angles. Comparing the two methods in terms of the torque forces and strain angles, the shafts producing entirely carbon fiber show the highest torque capacities; however, considering the cost and performance criteria, the hybrid shaft made up of carbon and glass fibers is the optimum solution for average demanded properties. Additionally, FE (finite element) model of the shafts was created and analyzed by using ANSYS workbench environment. Results of finite element analysis are compared with the values of twisting angle and torque obtained by experimental tests