Analysis of Test Results

The shear load-displacement (P – A) curves of all wall specimens are shown in Figure 4. Yield load of all walls could not been easily found from these curves, so all the characteristic loads including yield load were determined by the method prescribed in the Chinese Specification of Testing Methods for Earthquake Resistant Building (JGJ 101-96,1996). The method for determining the characteristic loads of wall is illustrated in Figure 5. The horizontal line AB was drawn form the point A defining maximum load Pmax, then the secant OD was drawn intersecting line AB and curve OA at point D and C, respectively, when the area ADCA was equal to the area CFOC. A vertical line was drawn form point D intersecting curve OA at point E. The shear load and the corresponding displacement of point E were the yield load Py and the yield displacement Ay of wall respectively. With the displacement increasing, the load descend; when the load descend to 0.85Pmax, the corresponding load and displacement were defined as the failure load Pu and the failure displacement Au. The test results determined by the method described above are presented in Table 2.

The yield load Py, maximum load Pmax and failure load Pu of SSO wall were approximately 2.87, 2.94, 2.94 times those of SSG wall under the monotonic loading test. In other words, the load capacity of the wall with single-sided gypsum sheathing was 34~34.8 % that of wall with single-sided OSB sheathing.

Fig. 5. Determination for special load point of specimens.

Table 2. Experimental results.

Wall type

Py (kN)

Ay (mm)

Pmax (kN)

Amax (mm)

Pu (kN)

Au (mm)

Shear

resistance (kN/m)

SSG

7.48

13.5

9.12

48

7.75

74.8

3.8

SSO

21.5

23.9

26.84

51.21

22.81

68

11.18

DSGO

29.12

19.6

34.99

59.62

29.72

74

14.58

The sum of yield load SSG wall and SSO wall was 28.98 kN, and the sum of maximum load of those two walls was 35.96 kN, the sum of failure load was 30.56 kN, which are close to the yield load 29.12 kN, the maximum load 34.99 kN and failure load 29.72 kN of DSGO wall respectively. Thus it can be seen that the total load capacity of two kinds of single-sided walls was close to that of double-faced walls with two corresponding kinds of sheathings.