The microstructure of steel is decisive for its chemical, physical and mechanical properties. Depending on the parameters characterising liquid metal as well as the parameters of the steel casting influencing the crystallisation process, the macrostructure of casts and ingots consist of three, two or only one crystallisation zone. In steel ingots, its most frequent by consist of three zones: ch...

Ultra-high performance concrete (UHPC) exhibits superior mechanical and durability with very high compressive strength. Compared ordinary concrete, it is more environmentally friendly has the great potential to be a practical solution improve sustainability of infrastructure. This study focuses on examining thermal properties UHPC coarse aggregates (CA-UHPC) subjected temperature ranged from 20...

In view of the poor accuracy and unsatisfactory effect shrinkage compensation for concrete-filled steel tubular structures large cross-sea bridge (CSTS-LCSB), a new technology CSTS-LCSB is proposed. The mechanism analyzed, including plastic shrinkage, dry autogenous carbonation shrinkage. proportion in ordinary concrete high-strength determined. has different forms environments, strain state en...

OBJECTIVE To evaluate the quantitative effects on torque expression of varying the slot size of stainless steel orthodontic brackets and the dimension of stainless steel wire, and to analyze the limitations of the experimental methods used. MATERIALS AND METHODS In vitro studies measuring torque expression in conventional and self-ligating stainless steel brackets with a torque-measuring devi...

This study focused on the evaluation of the machinability of different carburising steel grades by using a cemented carbide cutting tool during semi finishing of steel. The effect of the steel composition, microstructure and inclusion characteristics on the cutting tool wear in the soft part turning was evaluated for a reference steel R (0.028% S, 0.0009% O), a clean C steel (0.003% S, 0.0005% ...

During the last century the steel industry was influenced by several crises which invoked strong innovation activities in development of new classes of steels. innovation was based on the statement of representative of automotive industry bernhard rolinson who said: “Steel has a long tradition but despite of this its potential from the point of view of material properties is exploited only to 2...

Steel bracing members are widely used in steel structures to reduce lateral displacement and dissipate energy during earthquake motions. Concentric steel bracing provide an excellent approach for strengthening and stiffening steel buildings. Using these braces the designer can hardly adjust the stiffness together with ductility as needed because of buckling of braces in compression. In this stu...

The mechanism of corrosion of reinforcing steel in concrete is discussed based on electrochemical and electron microscopy observations. The importance of calcium hydroxide precipitation on the steel surf ace in the steel/mortar interface is evaluated by placing filter paper around reinforcing steel bar specimens prior to casting in mortar, thus preventing direct contact between steel and mortar...

Initiation of corrosion on reinforcing bars occurs when a critical chloride concentration is achieved. A universal value for the chloride concentration that causes depassivation has not been agreed upon for carbon steels due to a variety of experimental factors. The chloride threshold depends on the rebar material, rebar surface condition, testing environment, method of detection, definition of...