空間構造性能 Structural Performance 27. Aug / 2005Seismic Resistance of RC-framed Masonry Wall System1 RCM-2005 Seismic Resistance of RC-framed Masonry Wall System Osamu JOH Professor, Dr of Eng. Graduate School of Engineering Hokkaido University Turkey

空間構造性能 Structural Performance 27. Aug / 2005Seismic Resistance of RC-framed Masonry Wall System2 Objective and Method Objective: (1)To clarify seismic behaviors of RC-framed (=confined) masonry wall structures in consideration of many effective factors on the behaviors by experiment and analysis. (2)To propose easy rehabilitation method for the structures. Method: (1) Seismic loading tests of half scaled specimens with many test variables (opening configuration, types of blocks and joint, etc.) (2) Numerical simulation using rigid body spring method. (3) Experiment for the masonry wall structures strengthened by reasonable techniques (wire-mesh, new materials, etc.)

空間構造性能 Structural Performance 27. Aug / 2005Seismic Resistance of RC-framed Masonry Wall System3 Pilot test in 2004 Speci- men OutsideVariables RC- columns Joint type Axial stress L oading type CMW- 1 existstraightlow (  B /6) reversal MW-1nonstraightlow reversal MW-2nonbreaklow reversal MW-3nonstraighthigh reversal MW-4nonstraightlow one-way

空間構造性能 Structural Performance 27. Aug / 2005Seismic Resistance of RC-framed Masonry Wall System4 Failure of confined masonry wall crash Shear failure Forward loading Backward loading Maximum resistance in shear Degradation by crash of column

空間構造性能 Structural Performance 27. Aug / 2005Seismic Resistance of RC-framed Masonry Wall System5 Calculation of ultimate strength A. Ultimate bending strength of RC-framed wall B. Ultimate shear strength of RC-framed wall C. Ultimate shear strength of RC-framed & unreinforced wall D. Ultimate shear strength of reinforced wall without RC-frame Strength by wall reinforcement

空間構造性能 Structural Performance 27. Aug / 2005Seismic Resistance of RC-framed Masonry Wall System6 Specimen in 2005 Standard specimen Wall: (unit in mm) L=1750, H=1050, t=100, straight joint 120 bricks with holes Columns: D=225, t=100 axial bars = 6-D13 hoop = 2-6 compressive concrete strength = 30MPa

空間構造性能 Structural Performance 27. Aug / 2005Seismic Resistance of RC-framed Masonry Wall System7 Loading system Axial load Lateral load Shear span ratio =h/D First story in three stories Loading point

空間構造性能 Structural Performance 27. Aug / 2005Seismic Resistance of RC-framed Masonry Wall System8 Variables in 2005 (1) Shear span ratio: s No.1: (=standard) s = 1.0 = 2250/2200 No.4: s = 1.7 = 2250/ Loading height

空間構造性能 Structural Performance 27. Aug / 2005Seismic Resistance of RC-framed Masonry Wall System9 Variables in 2005 (2) Configuration of opening No.2: window opening = 890 x 560 mm 2 No.3: door opening = 450 x 1050 mm 2

空間構造性能 Structural Performance 27. Aug / 2005Seismic Resistance of RC-framed Masonry Wall System10 Future investigations-1 Extension of the experiment Consideration of effective factors on seismic performance 1) Configuration of overall structures number of story number of span 2) Three dimensional effect transverse structure transverse lateral loading 3) Properties of blocks and joint configuration, size,strength piling way of blocks, etc.

空間構造性能 Structural Performance 27. Aug / 2005Seismic Resistance of RC-framed Masonry Wall System11 Future investigations-2 Analytical investigation 1) Development of analytical model using “rigid body spring method” in order to apply to three different elements: RC-members, blocks and joints. 2) Numerical analysis considering several variables in order to extend the range of test results. effect of combination loads, configuration of walls, strength of material, etc. rigid body spring method

空間構造性能 Structural Performance 27. Aug / 2005Seismic Resistance of RC-framed Masonry Wall System12 Future investigations-3 Rehabilitation investigation Development of easy and reasonable strengthening methods for this structure by seismic loading tests. Methods are, for example, covering with wire mesh, jacketing with new material, partial protecting at wall corners, etc. Example of strengthening effects for RC wall-frame structure