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TECHNICAL PAPER

detailing and validate the natural frequencies/mode shapes. of 10 mm diameter bars respectively. Columns are reinforced
Very few literatures are available for comparing the ductile and with four numbers of 12 mm diameter bars. Lateral ties in the
non-ductile buildings with earthquake input using shake table. columns and beams are 6 mm diameter two legged stirrups at a
Most of the buildings are constructed in India based on IS 456 spacing of 150 mm c/c. Materials used are M 25 grade concrete
without considering the ductile detailing provisions as per IS and Fe 415 steel. In the two models, the first one (Model-1 RC
13920. Hence to evaluate the significance of ductile detailing building) is provided with a reinforcement detailing according
in the framed structures, this research study is carried out using to the IS 456 (Non-seismic detailing) . Second building (Model
[3]
the shake table test facility at CSIR-SERC. Even though this 2-RC ) is constructed with ductile detailing as per the code IS
project is initiated with two main objectives of studying seismic 13920 (Figure 2). Reinforcement details for both the frames are
[4]
performance behaviour of ductile Vs Non ductile structure and shown in Figure 3.1, Figure 3.2 and Figure 4.1 and Figure 4.2.
soft storey behaviour, in this paper, we would like to focus our
attention only on the investigation of ductile vs non-ductile 3.2 Description of Shake table
behaviour of reinforced concrete framed structure.
The shake table used for the experiment is 4m x 4m size with
payload capacity of 30 tons with servo controller. Required
3. EXPERIMENTAL INVESTIGATIONS
earthquake time history is given to the shake table in the form of
3.1 Building Details displacement values through the multi-directional actuators in
the shake table setup. Frequency of operation is 0.1Hz – 50Hz,
Two model buildings without ductile detailing (Model-1) and maximum acceleration is 1.0g (H and V) and maximum velocity
with ductile detailing (Model-2) are constructed for this study. is 0.8 m/sec. Design acceleration response spectrum for soft
The three dimensional reinforced concrete frame structure is soil given in Indian Standard code of practice (IS 1893: Part I)
[5]
having two-bays in X-direction, single bay in Y-direction with for design basis earthquake, modified for our model is used as
a total height of 4.8 m. A photographic view of the reinforced seismic input as shown in Figure 5
concrete building is shown in Figure 1. Each storey is 1.6 m
height. The section size of beams and columns are 150 mm 3.3 Test procedure
× 150 mm, with a 100mm thick slab. The base of the three The test specimen is fixed on the shake table at the required
dimensional reinforced concrete frame model is having a raft position. (Prakashvel et al. and Jothi saravanan et al. ) Base raft
[6]
[7]
foundation. The Model-1 building is designed as per IS 456 slab of the test specimen is connected to the shake table with
code.
high strength bolts to make it as a rigid base. An additional mass
The longitudinal beam and transverse beam reinforcement of 1200 kg has been added at each bay in a storey to represent
consist of four numbers of 16 mm diameter and four numbers the live load. Sweep sine tests are carried out to determine

Figure 1: A view of reinforced concrete building - Model-1 RC-without Figure 2: View of frame-RC - Model-2 (with ductile detailing) (IS: 13920)
ductile detailing (IS: 456)

10 THE INDIAN CONCRETE JOURNAL | AUGUST 2021