Bosai Solution ID : JBP00062

Ceiling having "Pair Locking Clip" are seismic resistant
The implementation of the newly developed "Pair Locking Clip" (i.e. joint bracketfor the prevention of the ceiling falling off down) in all building projects

HazardEarthquake Cyclone Tornado

Solution Purpose
Prevention & Mitigation

Solution Theme
Research & Investigation Disaster Prevention Plan Infrastructure Technology Building Technology
Products & Goods

Technology Subject
Technical Research & Development Legislation & Technical Regulations Mitigation Plan BusinessContinuity Plan Railways Airport Urban Facility for Disaster Prevention Design & Construction ofResilient Building Resilience Improvement on Existing Building Mitigation Measures for Interior &Facility Machinery & Equipment

Advantages"Pair Locking Clip" is a joint bracket for preventing the ceiling falling down, newly developed to＜ Downloaded from www.bosai-jp.org ＞

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withstand earthquakes. The Pair Locking Clip is intended for all building projects that has been orderedafter September 1, 2016. to give a sense of security to an owner of a building. The ceiling having "PairLocking Clip" are 3 times higher in strength as compared to the conventional ceiling and the same hasbeen verified through experiments/testing.

Solution Illustrated

BackgroundIn large earthquakes, the ceiling falling off damage are quite often reported. Also in the Kumamoto
Earthquake of April 2016, the ceiling falling off damage has been reported in the school and Hospital.
When failed false ceiling were observed, it has been pointed out that the vulnerability of the bracket(Clip) (which Join the ceiling joist and joist receiver) is the main cause of the failure of false ceiling
falling off. Thus reinforcing the important element (Bracket/Clip) will reduce the risk of false ceiling
falling off damage.
We have developed our own "Pair Locking Clip", a bracket to firmly attach the ceiling joist (i.e. ceilingfoundation) with the receiver of the ceiling joist. The "Pair Locking Clip" has been verified throughexperiments to have 3 times more strength as compared to the conventional method of constructionthat include JIS clip. We have decided to implement the newly developed "Pair Locking Clip" (i.e. joint
bracket for preventing the ceiling falling down) in all building project that has been ordered afterSeptember 1, 2016.
We are implementing the same technique in the Design Build Projects and are striving hard along with
our subsidiary company Chiyoda Kenko (Co. Ltd), material suppliers and trading companies to promoteamong the different Clients and Engineers the "Pair Locking Clip" for future construction projects.
Thus we have our belief that we have significantly contributed to the protective measures taken forceiling falling off damage prevention.

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Exposition of the Solution■Features
The "Pair Locking Clip" has the following features.
① It consists of a simple material, with each pair containing two clips, and have a simple mechanism tofasten the receiver Joist.
② The interlocking is tight as the pair of clips clipped in each other (refer to Figure 4).

③ The Fastening by pushing it with the finger has made it convenient and fast. Screws and bolts are notneeded.
④ We have developed two type of "Pair Locking Clip”, one is for existing building and the other for
newly constructed buildings.
■ Verification experiment
In order to verify the performance of the "Pair Locking Clip", three types of experiments have beenconducted. The material experiments, ceiling unit experiments and dynamic excitation experiments forlarge scale ceiling. By performing each of these experiments, as well as keeping in view the physicalproperties of the material we have evaluated and confirmed the overall safety and seismic performanceof both the conventional ceiling JIS clip and "Pair Locking Clip" ceiling.

Achievements of Examples
Material Experiment results
In the material experiment, the clip has been pulled in the vertical direction, to verify the strength andrigidity, thus it has been proved that "Pair Locking Clip" has enough strength as compared to JIS clip, wehave an anti-wind pressure clips and have equivalent strength and rigidity. The experiment/test results
are depicted in Figure 5 and Figure 6.

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■ Ceiling Unit Experimental Results
The Unit Experiment has been conducted with the predetermined Loads with plain compression. Duringexperiment, JIS clip has been damaged as the claws become open but no impairment has been
observed in the "Pair Locking Clip”. The experiment/test results are depicted in Figure 7 and Figure 8.

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■ dynamic vibration test results
We conducted a vibration experiment by reproducing the 2011off the Pacific coast of Tohoku
Earthquake wave (JMA Sendai wave), to strike against the real large-scale ceiling (of size 7.5 m× 4.8m
×1.5m (Height x width x depth)) and wall.
Pair Locking Clips were observed under vibration of 2.2G (i.e. Equivalent to the seismic intensity of 7)
and the results have confirmed that there no damage or loss to the "Pair Locking Clip" ceiling.
In addition to this, the amount of strain observed in the engagement portion and in the vertical portionof the "Pair Locking Clip" was also very small which justifies its good quality. Figure 9 reference＜ Downloaded from www.bosai-jp.org ＞

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Other References

Corporate Profile
TODA CORPORATION
Kyobashi-Nisshoku Building 2F, 8-7, Kyobashi, 1-chome, Chuo-ku, Tokyo, 104-8388, Japan Tel. : +81-3-3535-1591
 E-mail : shinsuke.noshita@toda.co.jp
 Website : http://www.toda.co.jp/english/index.html＜ Downloaded from www.bosai-jp.org ＞

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