14 POST-TENSIONED COUPLED WALLS Unbonded post-tensioning is a promising and feasible method to couple concrete walls (up to percent coupling)Large self-centering, considerable energy dissipationLarge deformations with little damageThe analytical models and design tools/procedures work wellShift focus towards precast beams
15 PRECAST ADVANTAGES Simpler beam-to-wall joints Central location of PT strandsFire and environmental protectionHigher friction resistance against shear slidingFavorable tolerances for constructionCost-efficient
16 PARAMETRIC STUDY DRAIN-2DX (Half-Scale Subassemblages) Beam Depth (in)AnglePT StrandsGage Length (in)Aspect Ratio14L8x4x1/233.2154L8x4x5/8182.5Varied Parameters:beam depthamount of PTangle sizegage lengthaspect ratio
17 TEST SPECIMENS (Half-Scale) Beam Depth (in)AnglePT StrandsGage Length (in)Aspect RatioParameter14L8x4x1/2353.21Baseline Test4apL8x4x5/8182.5Depth, aspect ratio
18 TEST SPECIMEN CROSS-SECTIONS (Half-Scale) L8x4x1/2L8x4x1/214”14”7”7”L8x4x5/8L8x4x1/214”18”7”7”
23 MAXIMUM PRINCIPAL STRESSES If we take a look at the Smax Principal stresses, we see the tensile stresses that are developed in the system. Anything in red, is greateer than the tension strength of concrete and critical for shear design. However, to take advantage of our unique system, we are using abaqus to help in the shear design.