Study on the numerical analysis for structural detail of timber frame ...

More documents

Recommendations

Info

Figure 12: Compressive strain inclined to the grain (R00T) Figure 13: Compressive strain inclined to the grain (R05T) Figure 14: Compressive strain inclined to the grain (R10T) 3 CROSS-SHAPED FRAME TEST 3.1 EXPERIMENT OUTLINE In this study, cross-shaped frame is made using non-knot cedar wood with column cross section 100100mm and nuki-beam cross section 40100mm. The column upper and bottom ends are restricted by the pin support as shown in Figure 15. Intertru ss 振れ止め Load P 1 Disp. 1 Disp. 2 200 200 DG3 DG5 + - DG1 50 50 DG7 DG4 100 300 DG6 100 DG8 250 250 500 250 250 300 160 DG10 DG11 DG12 DG13 160 DG9 50 50 200 振れ止め DG2 Intertru ss Load P 2 - + Figure 15: Test specimen dimension and displacement measurement position The loading test was carried out by using two electronic control actuators to applied antisymmetric vertical displacement for the nuki beam ends. Cotter pin 40 60 304030 140 140 2060 20 込栓(15×15) 304030 20 60 40 2060 20 20 くさび Wedge 20 Wedge くさび Wedge くさび Model A (Complete nuki joint) Model B (Link nuki joint) Model C (Link nuki joint with cotter pin) Figure 16: The details of the each test specimen juncture The frame models were made 3 types which different of the joint detail as shown in Figure 16. The model A is complete continuous beam joint, and the horizontal beam member is one part element (it is called complete nuki joint). Model B is the joint processing the right and left members like key-shape, and consist of discontinues beam (it is called link nuki joint). Model C is stricken the cotter pin to the linke nuki joint, and the discontinuous beam is fixed in the connection inside (it is called link nuki joint with cotter pin). These joints have also fixed by driving two wedges (zelkova material) on the upper clearance between column and beam. The details of each part are shown in Figure 16. The whole view of Model A is shown in Figure 17. The Model A has been bound the 1/3 span from the edge of the horizontal bracing for out-of-plane deformation by steel pipes (intertruss braceing) which covered PTFE sheet to reduce the friction.
Figure 17: Test specimen Model A The loading program is shown in Figure 18, and the target displacement each 3 cycles (for deformation angle: 1/50rad, 1/20rad, 1/15rad, 1/450rad, 1/300rad, 1/200rad, 1/150rad, 1/100rad, 1/75rad ) is antisymmetric displacement control which repeatedly increased. Throughout this paper, the load and displacement of left side is described by symbol P1 and 1, the load and displacement of right side is described by symbol P2 and 2. The sign was defined for the direction of the arrow respectively shown in Figure 15. Target displacement(mm) 80 60 40 20 0 -20 -40 -60 -80 1/450 1/300 1/200 1/150 1/100 1/75 1/50 1/20 1/15 0 6 12 18 24 30 Cycles 36 42 48 54 60 Figure 18: The loading program 3.2 RESULT OF THE EXPERIMENT Figure 19 shows the load P1- displacement 1 relation and Figure 20 shows the load P2- displacement 2 relation for Model A. The sign of the load and displacement are defined the direction of the arrow as shown in Figure 15. From these figures, it is proven that the mechanical characteristics under the loading region for displacement 15mm (for deformation angle: 1/50rad) in Model A is approximately symmetric behavior. Figure 21 shows the load P1- displacement 1 relation and Figure 22 shows the load P2- displacement 2 relation for Model B. From these figures, It is proven that the mechanical characteristics under the loading region for displacement 15mm (for deformation angle: 1/50rad) in Model B is unsymmetrical behaviour different from Model A. Also, it tends to show the linearity deformation and low rigidity for the positive load and deformation in the direction for the first quadrant of the graph. But, it tends to show the large slip hysteresis curve for negative load and deformation in the direction for the third quadrant of the graph. These are supposed the effect of the discontinuous beam connection shape and driving two wedges in the Model B. Load P1(kN) 0.8 0.6 0.4 0.2 0 -50 -30 -10 10 30 50 ‐0.2 ‐0.4 ‐0.6 ‐0.8 Displacement (mm) Figure 19: The load P1- displacement 1 relation (Model A). Load P2(kN) 0.8 0.6 0.4 0.2 0 -50 -30 -10 10 30 50 ‐0.2 ‐0.4 ‐0.6 ‐0.8 Displacement (mm) Figure 20: The load P2- displacement 2 relation (Model A). Load P1(kN) 0.8 0.6 0.4 0.2 0 -50 -30 -10 10 30 50 ‐0.2 ‐0.4 ‐0.6 ‐0.8 Displacement (mm) Figure 21: The load P1- displacement 1 relation (Model B). Load P2(kN) 0.8 0.6 0.4 0.2 0 -50 -30 -10 10 30 50 ‐0.2 ‐0.4 ‐0.6 ‐0.8 Displacement (mm) Figure 22: The load P2- displacement 2 relation (Model B). Figure 23 shows the load P1- displacement 1 relation and Figure 24 shows the load P2- displacement 2 relation for Model C. From these figures, more
Page 1 and 2: Study on the numer
Page 3: Load-compressive strain relation of

Study on the numerical analysis for structural detail of timber frame ...

You also want an ePaper? Increase the reach of your titles

Delete template?

Save as template?