This article examines the influence of various factors on the precision of 3D printed objects produced through Fused Filament Fabrication (FFF) using Polylactic Acid (PLA) as the primary material. While PLA is widely chosen for its compatibility with biological applications, it does suffer from limited dimensional accuracy. The study focuses on investigating the effects of four independent parameters, namely layer height, infill density, printing speed, and the number of top and bottom layers, on accuracy along the three axes of length, width, and depth.
View Article and Find Full Text PDFCracking is a significant concern for pavements and should be appropriately treated during road, highway, and runway rehabilitation. This study investigates the behavior of asphaltic materials under tensile and shear loading modes in intact, fractured, and repaired conditions. With this aim, several methods and materials are utilized for repairs, such as poring adhesive into the crack (using bitumen, neat epoxy resin, and polymer concrete adhesives) and patching the crack with textile (by glass fiber and epoxy resin or bitumen).
View Article and Find Full Text PDFThe most frequently used construction material in buildings is concrete exhibiting a brittle behaviour. Adding fibers to concrete can improve its ductility and mechanical properties. To this end, a laboratory study was conducted to present an experimental model for the specimens' size effect of on macro-synthetic fiber-reinforced concrete using variations in fracture energy.
View Article and Find Full Text PDFJ Mech Behav Biomed Mater
March 2020
A modified single edge cracked bend beam specimen called "inclined edge crack asymmetric bend" (IE-CAB) specimen was designed and proposed for investigating mixed mode I/II fracture toughness behavior of brittle materials. Using a large number of finite element analyses performed for different geometry and loading conditions, it was demonstrated that unlike the conventional single edge notch beam specimen, the IE-CAB configuration can provide full combinations of mode mixities from pure mode I to pure mode II. Then the IE-CAB specimen was employed for mixed mode I/II fracture toughness testing of two PMMA based denture materials (i.
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