Patricia Luna

Experimental Analysis of Frames Made with Glued Laminated Pressed Bamboo Guadua

This article presents the experimental tests results of frames made with glued laminated pressed bamboo guadua under lateral load. The tested frames had two floors with 1.40m of height each one and 2.80m of total height; the width of the frames was 2.10m. Beams and columns had square box cross-section of 0.10m side and 0.015m of wall. Three frames had bracing type K and other threes had panels. The adhesive used for the manufacture of beams, columns and braces was Urea Melamine Formaldehyde and for the elaboration of panels was Polyvinyl Acetate. The frames of glued laminated pressed bamboo guadua had elastoplastic behavior with great ductility.

Determinación experimental de valores característicos de resistencia para Guadua angustifolia

For the design of structures built with bamboo Guadua angustifolia as structural material it is necessary to know the characteristics values of its mechanical properties and elastics modulus. This article shows the experimental methodology used in the determination of characteristics values for bending, compression, shear and tensile parallel to fiber, torsion, compression perpendicular to fiber and elastics modulus for Guadua angustifolia. Tests were performed in samples taken from the bottom, middle and upper parts of culms of bamboos from three different areas of Colombia. Characteristic values of compression, tension and shear parallel to the fiber, bending, torsion and perpendicular compression strengths were found. Also the elastic longitudinal modulus and the circumferential modulus were determined.

Mechanical Behavior of Glued Laminated Pressed Bamboo Guadua Using Different Adhesives and Environmental Conditions

This paper presents the mechanical properties measured on glued laminated pressed guadua samples. Experimental tests like shear parallel to fiber, tensile and shear perpendicular to fiber and flexural tests were carried out using three different types of adhesives: European Melamine Urea Formaldehyde, Colombian Melamine Urea Formaldehyde, and Polivinil Acetate humidity resistant. In order to study the behavior of the material in aggressive environmental conditions, half of the samples used in the mechanical tests were introduced in a temperature and humidity chamber for 45 days set to 45°C of temperature and 95% of relative humidity, usual environmental conditions in Chocó Colombia.The results showed that the highest values of mechanical strength were obtained for samples made with European Melamine Urea Formaldehyde. In addition, it was found that this adhesive was the one with better behavior under the aggressive environmental conditions simulated.

Determination of the Delamination Percentage of Compacted Bamboo Guadua Using Extended Field Digital Images Processing

The percentages of delamination of Compacted Bamboo Guadua were calculated using digital images processing. Three processes were done in the development of this project: tests of delamination, digital image pre-processing and digital image processing of the images acquired. The test of delamination followed the ASTM 5824. The digital image pre-processing was supported on the acquisition of sequences of images, doing a sweeping of the samples, and finally the digital processing worked in the generation of panoramas with sequences of images acquired from the sample. Additionally, the total area from the sample was measured digitally, the segmentation and the measurement of delamination area were done, finding the ratio between the delamination area and the total area of the sample, and obtaining the value of percentage of delamination per section. Digitally, the obtained values for samples made with fibers obtained from Stick (Varillón), Top (Sobrebasa), Middle (Basa) parts and mixture of them were 16.97%, 9.96%, 5.96% and 8.64% respectively.