Rigid Body Motion Conversion Due to Impact

The impact phenomena may be related not only to instantaneous constraining of moving body, but also to instantaneous release from constraint. Both in the first and in the second case motion parameters after impact change, trajectory and type of motion may also change. In this work the conversions of translatoty motion into plane or rotary and vice versa, and spherical into rotary due to impact are considered. The conditions of conversion of one motion type into another and parameters post-impact are studied. Problems are solved in framework of rigid body motion and impact. Studying of such phenomena is important for location of parts on industrial conveyors, feeders, etc

Numerical Simulation of Fiber Pull-out of Elastic Matrix with Friction

Traditionall

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Strength of Layered Fiberconcrete

In the present research three different types of layered prisms with the same fibers amount in them, were experimentally produced (four samples with dimensions 10x10x40cm were fabricated for each type as well as for reference, four prisms with homogeneously dispersed fibers were produced also). Prisms were tested under four point bending conditions till crack (in each prism) opening

Inclined Single Elasto-Plastic Fiber Pull Out of Elastic Volume with Friction

It is well known that the main disadvantage of concrete is its low tensile strength. It has been proven by many researchers that the overall behaviour of concrete can be improved by the addition of fibers. A wide range of fibers is used for the production of fiber reinforced concrete (steel, plastic, glass, etc.). The positive effect of the fibers is not obvious until the first crack occurs in the concrete. Increasing the applied loads the matrix fracture process is initializing: micro-cracks start to open to grow and to coalescent finally forming one or few macro-cracks. The fibers are bridging the crack

Micromechanics of Elasto-Plastic Fiber Pull out of Elastic Matrix

It has been proven by many researchers that the overall behavior of concrete can be improved by the addition of fibers. In the present investigation numerical (FEM) modeling of elastically plastic single straight fiber pull-out of elastic matrix volume was realized

Fibre Reinforced Concrete (FRC) (with Glass, Steel and Carbon Fibres)

An AR glass carbon and steel fibre concrete strength and post cracking behaviour was investigated experimentally

About Possibility to Predict Fibers Orientation and Distribution in Viscous Flow

Short fibers as reinforcement are used in many structural applications in aerospace, automotive, machine building and civil engineering industries. Important part of fabrication technologies for such materials is base on structural element mould filling by liquid matrix with short fibers. Traditionally the matrix is viscous (polymers, fresh concrete). After maturing and demolding structural element mechanical properties are highly dependent on fiber distribution and orientation in the element body. For example, polymer matrix composite with short glass fibers or steel fiber reinforced concrete post cracking behavior and load –bearing capacity are dependent on the number of fibers crossing the weakest crack (bridged the crack) and their orientation to the crack surface [1-3]. This is why it is important to investigate this process

Numerical Modeling of Single Steel Fiber Pull out of Concrete

Single fiber pull-out curves obtained numerically and experimentally, results are compared

Mechanical Properties Investigation of Cotton Stockinet and Their Composites

Natural fibers as the reinforcement in polymer composite materials are attracting additional attention during last years. Cotton, flax and hemp fibers together with the number of other natural fibre materials are being considered as an environmentally friendly and relatively lowcost alternative of synthetic reinforcement in structural composites