Shear Behavior of Bamboo Reinforced Concrete Beams

This research work aimed to study the usage of Bamboo strips as shear reinforcement in reinforced concrete (RC) beams. Four beams were considered in this study. The flexural reinforcement for all beams was the same. As for shear reinforcement, one beam was reinforced with conventional shear reinforcement with spacing (s=180 mm), while the other three beams were reinforced with bamboo strips with three different spacings (s=180 mm, s= 90 mm, and s=60 mm). The beams were subjected to a four-point bending test to plot the load-deflection curve for each beam. Results showed that the beam reinforced with bamboo strips spaced at 180 mm has 30% higher shear capacity than the beam with conventional shear reinforcement at the same spacing. Also, as the spacing of bamboo strips decreased, the shear capacity of beams increased nonlinearly.

Numerical and Experimental Study of Five-Layer Non-Symmetrical Paperboard Panel Stiffness

This paper concerns the analysis of five-layer corrugated paperboard subjected to a four-point bending test. The segment of paperboard was tested to determine the bending stiffness. The investigations were conducted experimentally and numerically. The non-damaging tests of bending were carried out in an elastic range of samples. The detailed layers of paperboard were modelled as an orthotropic material. The simulation of flexure was based on a finite element method using Ansys® software. Several material properties and thicknesses of papers in the samples were taken into account to analyse the influence on general stiffness. Two different discrete models based on two geometries of paperboard were considered in this study to validate the experimental stiffness. The present analysis shows the possibility of numerical modelling to achieve a good correlation with experimental results. Moreover, the results of numerical estimations indicate that modelling of the perfect structure gives a lower bending stiffness and some corrections of geometry should be implemented. The discrepancy in stiffness between both methods ranged from 3.04 to 32.88% depending on the analysed variant.

Crushing of Double-Walled Corrugated Board and Its Influence on the Load Capacity of Various Boxes

As long as the non-contact digital printing is not a common standard in the corrugated packaging industry, corrugated board crushing is a real issue that affects the load capacity of the boxes. Crushing mainly occurs during the converting of corrugated board (e.g. analog flexographic printing or laminating) and is a process that cannot be avoided. However, as show in this study, it can be controlled. In this work, extended laboratory tests were carried out on the crushing of double-walled corrugated board. The influence of fully controlled crushing (with a precision: ±10 μm) in the range from 10 to 70 % on different laboratory measurements was checked. Most of the typical mechanical tests were performed e.g. edge crush test, four-point bending test, shear stiffness test, torsional stiffness test, etc. on reference and crushed specimens. The residual thickness reduction of the crushed samples was also controlled. All empirical observations and performed measurements were the basis for building an analytical model of crushed corrugated board. The proven and verified model was then used to study the crushing effect of the selected corrugated board on the efficiency of simple packages with various dimensions.