Strength and deformability of normal cross sections of reinforced concrete beams, reinforced in the tension area with additional sheet reinforcement without the bond

The results of the experimental research of the strength and deformability of normal cross sections of reinforced concrete beams reinforced in tension area with additional sheet reinforcement without the bond.

Експериментальні дослідження міцності та деформативності армокам’яних згинаних елементів

The results are given on the basis of an experimental research on firmness and deformability of normal sections of concrete beams reinforced with frameless reinforcement and rod reinforcement class A400C without prestressing. These experiments and comparing them with calculations according to current regulations give an opportunity to assess the convergence of the results and draw conclusions about the possibility of rational design of ceramic block bending elements with double reinforcement in the area of the normal forces.

Технічні рішення реконструкції моста із збірними залізобетонними попередньо напруженими прольотними будовами

The existing bridge designs and variations of design decisions reconstruction of the bridge expansion monolithic or precast-monolithic concrete slab and enhancement bill beams change their static circuit with a split on a continuous are described.
The existing span structure reinforced concrete, ribbed beam cross-cutting scheme
10 × 16,8 m clearance Г-7 + 2 × 0,9 m was built in 1960–64 years as a pilot facility construction of prestressed beams by Ukrdortrans NDI (now DerzhdorNDI).
Reconstruction span structure included its extension to clearance Г -10 + 2 × 1,0 m

Polymers as natural nanocomposites. 1. the reinforcement structural model

The structural treatment of amorphous glassy polycarbonate as natural nanocomposite was proposed. It has been shown that the polycarbonate stiffness is defined completely by the state of its structure, which is described within the frameworks of a local order model. The large reserves of stiffness raising for amorphous glassy polymers are demonstrated.

Polymers as Natural Nanocomposites. 2. The Comparative Analysis of Reinforcement Mechanisms

The complete similarity of reinforcement degree behaviour has been shown for nanocomposite epoxy polymer/Na+-montmorillonite and polyarylate, which is considered as the natural nanocomposite. The polyarylate structure description is given within the framework of cluster model of polymers amorphous state structure. The interfacial adhesion level influences strongly the reinforcement degree of indicated materials.

Polymers as Natural Nanocomposites. 3. The Geometry of Intercomponent Interactions

The treatment of amorphous glassy polymers as natural nanocomposites is proposed. It has been shown that the geometry of intercomponent interactions nanoclusters – loosely-packed matrix defines adhesion level between the indicated components of natural nanocomposites. Since nanoclusters – loosely-packed matrix contact is realized over cylindrical surface of the first ones then the larger the indicated surface area the higher the intercomponent adhesion level.