This paper analyzes the effect of partial sand replacement by sugarcane bagasse ash in mixed mortars utilizing a 1:2:9 mix proportion by volume for cement, lime and fine aggregate. The ash is characterized by its part...This paper analyzes the effect of partial sand replacement by sugarcane bagasse ash in mixed mortars utilizing a 1:2:9 mix proportion by volume for cement, lime and fine aggregate. The ash is characterized by its particle distribution, pozzolanic activity, chemical composition, bulk density, moisture content and loss on ignition. The mortars are then produced with a constant water/cement ratio of 2.64 and a partial replacement of sand with sugarcane bagasse ash using different substitution percentages (0%, 5%, 10%, 15% and 20%). The mortars are characterized in the plastic state: water retention, bulk density and air content, and in the hardened state: capillary coefficient, tensile strength by bending test, axial compressive strength and flexural and longitudinal Young’s modulus. The statistical analysis of the results showed that the ash can be incorporated into mortars without causing significant alterations in its properties.展开更多
Cellular beams are appropriate for large spans with relatively small loads or for conditions in which strain dictates dimensioning. Another important advantage of cellular beams is the possibility of passing utility d...Cellular beams are appropriate for large spans with relatively small loads or for conditions in which strain dictates dimensioning. Another important advantage of cellular beams is the possibility of passing utility ducts through the openings, which avoids cutting through the web of the beam or increasing the construction height, which occurs when the ducts pass under the beams. Geometrical imperfections result from a lack of straightness during fabrication of rolled profiles. Geometric imperfections are represented numerically by an initial curvature. Additionally, the physical imperfections of rolled profiles result from the appearance of residual stresses. The condition that creates residual stresses in steel is the result of thermal and mechanical industrial processes. In this study, numerical analyses are performed with cellular beams using Finite Element Method software. During the simulations, through non-linear geometric and physical analyses, geometric imperfections were varied, where lateral torsional buckling in cellular beams was considered as a function of the unrestrained length. In the boundary, conditions were restrained displacements in the axis X, Y, Z and rotation about X-axis, thus simulating the fork support. The beams are submitted to uniform bending and concentrated load. The results from the numerical analyses were compared with the calculation procedures, which verified that the results were significant.展开更多
文摘This paper analyzes the effect of partial sand replacement by sugarcane bagasse ash in mixed mortars utilizing a 1:2:9 mix proportion by volume for cement, lime and fine aggregate. The ash is characterized by its particle distribution, pozzolanic activity, chemical composition, bulk density, moisture content and loss on ignition. The mortars are then produced with a constant water/cement ratio of 2.64 and a partial replacement of sand with sugarcane bagasse ash using different substitution percentages (0%, 5%, 10%, 15% and 20%). The mortars are characterized in the plastic state: water retention, bulk density and air content, and in the hardened state: capillary coefficient, tensile strength by bending test, axial compressive strength and flexural and longitudinal Young’s modulus. The statistical analysis of the results showed that the ash can be incorporated into mortars without causing significant alterations in its properties.
文摘Cellular beams are appropriate for large spans with relatively small loads or for conditions in which strain dictates dimensioning. Another important advantage of cellular beams is the possibility of passing utility ducts through the openings, which avoids cutting through the web of the beam or increasing the construction height, which occurs when the ducts pass under the beams. Geometrical imperfections result from a lack of straightness during fabrication of rolled profiles. Geometric imperfections are represented numerically by an initial curvature. Additionally, the physical imperfections of rolled profiles result from the appearance of residual stresses. The condition that creates residual stresses in steel is the result of thermal and mechanical industrial processes. In this study, numerical analyses are performed with cellular beams using Finite Element Method software. During the simulations, through non-linear geometric and physical analyses, geometric imperfections were varied, where lateral torsional buckling in cellular beams was considered as a function of the unrestrained length. In the boundary, conditions were restrained displacements in the axis X, Y, Z and rotation about X-axis, thus simulating the fork support. The beams are submitted to uniform bending and concentrated load. The results from the numerical analyses were compared with the calculation procedures, which verified that the results were significant.
