Issue 30

C. Yunyu, Frattura ed Integrità Strutturale, 30 (2014) 545-551; DOI: 10.3221/IGF-ESIS.30.65

transformation layer or not and what measures should be adopted to strengthen it, all of which are very important to guarantee the seismic safety of the structures [8].

Figure 5: The comparison of the lateral layer stiffness ratio

The lateral layer stiffness comparison of the upper and lower structure layers in the transformation layer generally only considers the shear deformation of the shear wall. If we suppose that both ends of the column undergo no rotation, the calculation formula for the approximate layer’s total lateral stiffness i k of bending deflection will be considered, namely:

i i GA k h

(8)



i

where:

i j A A A    , wi wji wi

A is the effective cross-section area of the entire shear wall on the th i storey along the calculation

direction (excluding the flange area); i h is the storey height of the th i layer; G is the shearing modulus of elasticity of the shear wall concrete on the th i storey. When the storey features columns, i

A should still contain the lateral rigidity when assuming that both ends of the pillar

have no rotation, which is approximated by the following type:

i j A A C A    wi ij

(9)

cij

h

2 2.5( ) cij

(10)



C

ij

h

i

where: cij h is the cross-section height of the th j pillar on the th i storey along the calculation direction.

It is explicitly stipulated in new high gauge that when the transformation storey is on the 1 th and 2 th layer, the equivalent shear stiffness ratio between the transfer storey and its adjacent superstructure could be adopted to represent the upper and lower structural change of structural stiffness on the transfer storey. When the transfer storey is on the 1 th storey,

1 1 2 2 2 1 G A h G A h

(11)

1  

where: 1 2

, h h is the storey height of the 1 th and 2 th layer. When the transfer storey is on the 2 th layer,

h G A

(12)

3 2 2

2  

G A h

2 3 2

549