SPECIAL CONNECTION FOR PRECAST WALLS
SUBJECTED TO DYNAMIC LOAD
Project Leader: Dr. Farzad Hejazi
Project Member: Ramin Vaghei, Prof. Dato' Ir. Dr. Mohd Saleh Jaafar,
Prof. Abang Abdullah Abang Ali, Hafez Taheri
Department of Civil, Faculty of Engineering, UPM
Email: farzad@upm.edu.my
Summary
One of the most vital and controversial issues in the precast structures which subjected to the
dynamic loading including seismic loading and vibration is the integrity of structure.
Therefore, there is huge tendency among the structural engineers who are involving with
construction, especially in seismic zones, to come up with new connection, which is really
efficient in terms of performance, construction cost and time; The present invention relates to
development of special connection for precast walls in Industrialized Building System (IBS)
subjected to dynamic loading due to ground motion, earthquake, wind, tsunami, machine
vibration, etc. The system comprising two steel U shaped channels as male and female
channel which attached to the walls and connect the walls to each other using bolt and nuts.
The Rubber Channel also is implemented between male and female channel to reduce
dynamic force and dissipate vibration effect.
The configuration of developed connection is design in order to perform in all direction (6
degree of freedom) to resist multidirectional dynamic force such as axial, shear and torional
force and bending moment. Implementing of proposed connection is lead to increase integrity
of structural component during vibration and show high efficiency, desirable performance
against dynamic load, affordable cost and reasonable construction time. The new precast
connection is consider as one of the inventive energy dissipation connection by implementing
the latest concept of rubber damping which can increase the overall lateral resistance capacity
and damping characteristic of the structures subjected to vibration and it can be assure the
serviceability and safety design criteria.
The performance of a precast connection is evaluated by dynamic analysis of numerical
model and conduct experimental test. The results reveal the efficiency of proposed precast
connection to diminish and dissipate the energy compared with conventional precast
connection such as loop connection.
Market potential
Local market:
This product can be very beneficial since the building industry in Malaysia is growing
towards industrialization in construction, and it peruses the engineers who are dealing with
construction in seismic zones such as Sarawak to make up the deficiencies associated with
lateral resistance in structure against excitation.
Global Market:
The novel connection has high market potential in the all countries that lateral loadings are
significant and located near fault lines such as Indonesia, Japan, Srilanka, India etc.
Keywords: Industrialized Building System, Precast Wall, Connection, Finite Element Model,
Rubber Material, Dynamic Load, Earthquake.
Product profit
 A new precast wall connection system for Industrialized Building Systems (IBS) which
is able to resist against multidirectional dynamic load.
 Proposed connection shows effective performance in joints in comparison with common
connection which are subjected to inplane/out-of-plane loading in static or dynamic
form.
 Capacity, energy absorptions are significantly rising up; however, vulnerability of
precast concrete structure is decreased against severe excitation such as earthquake and
vibration.
 Proposed connection provides feasibility in terms of time and cost of construction as two
important features, which are considered during the construction of industrialized
building systems.
 New precast connection is compatible with various positions of building joints, including
wall to wall, interior wall-exterior wall and wall to slab.
 Proposed precast connection is increasing the sustainability of structure as well as the
ductility of industrialized building systems through diminishing the effect of severe
excitation or dynamic load.
 New analytical model and constitutive law for proposed connection are developed.
Furthermore, new finite-element model for proposed connection is derived.
 The proposed connection can be done by unskilled workers and there is no dependency
on manual foreign labours.
 The new precast connection for IBS, not only improved the quality and productivity of
construction, but also it less use of equipment.
Industrial Application
 Housing Research Center
 Consultant companies and contract companies
Short Description about Research Output:
The new connection system for precast walls is developed, which is applicable in
Industrialized Building System subjected to multidirectional excitation in all 6 degrees of
freedoms. Proposed connection between two adjacent panels with reinforcement (BRC) is
comprised of steel channels, rubber; steel hooks, bolts and nuts. Steel hooks keep the
channels rigid enough to the panels; however, steel channels and rubber act as structural
members in precast connection in IBS, and they are contributed to carry the loads by the
former and dissipate the energy by the latter. The novel connection provides so many
benefits, including speed up the construction, quick replacement by the new one after severe
damage, saving cost, increasing the strength. Furthermore, proposed connection can dissipate
the energy by the rubber, which is located at the core of connection, against large vibration
amplitude or severe excitation such as an earthquake restrain to remain its high flexibility.
The current invention supposed to present new system for connection of precast concrete
structures which seeks to ameliorate the disadvantages of the common connections such as
loop connection which is applicable in reinforced concrete structures by providing noticeable
resisting against different types of loading include of inplane or out-of-plane static and
dynamic load. Figure 1 shows the isometric view of the proposed connection between two
precast concrete panels as well as the elements used in color, including Steel Channels,
Rubber, Bolts and Nuts. Figure 2 represents of prototype of proposed wall to wall connection.
1-Steel Channel (Female Wall) 2-Steel Channel (Male Wall) 3-Rubber 4-Bolts and Nuts
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Figure 1: Isometric View of Proposed Precast Walls and Connection
Figure 2: Prototype
Figure 3: Experimental Test