Building Construction, Renovation, Maintenance & Advice

Making Money Out Of Nothing and earthquake Damage

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Earthquakes

Well unfortunately earthquakes do happen, in fact we have just had one in 2011. Not a big one but certainly the largest most people can remember for quite a while.

According to the US geological survey it was a magnitude 6.1 situated 140 kilometres South West of Nusa Dua at a depth of 35 kilometres. Just for the record earthquake history in this area includes a severe earthquake on 14th July 1976 which killed 563 people and a moderate earthquake magnitude 6.5 on 28th September 1998 that killed 1.

As we have discussed before the effect of earthquakes at a local level are as predictable as a tattooist with parkinson's disease. In our recent earthmovement several buildings in localised areas were damaged while many others in close proximity were relatively unharmed, such is the quirkiness caused by the complex formation of the earth's crust and the resonance of vibrations that pass through it. All we can do is make buildings strong enough to withstand some pretty heavy duty shocks and vibrations.

I spoke to a good friend who runs his business from one of the buildings damaged, a row of rukos near the Dewa Ruci roundabout. He reports that the building itself is sound with no cracks in the structure or walls. The damage was, in fact, roof tiles and concrete adornments being shaken off most notably a concrete facade along the top of the front walls which cracked and pieces of which broke away falling across the front of the building. This made it very dangerous for anyone trying to leave the building. It appears the concrete structure of the building itself was well designed and properly built, the added adornments however, were not properly locked into the main structure and this is what caused the problems.

Inspect your buildings for earthquake damage

Now is probably a very good time to take a look at your buildings and check for damage. Quite often damage is easy to spot. Walk around the outside of the building systematically checking each wall from top to bottom looking for cracks or signs of movement. Particularly see if there are serius cracks that might make the building unsafe. If your walls have stone cladding you might find parts that have fallen off.

Look at the roof and see if there are any tiles moved or missing.

Move inside and check all the walls and ceilings for cracks. Walk around the floors in each room and see if there are any cracks or gaps opened up between the tiles.

So much for the obvious but be careful there may be damage, however, that is not so easy to see particularly if your building has stone or other cladding that is hiding the structure beneath. Here are some ways you might look for clues.

Go around and check all the windows and doors and see if they still open and close properly. Movements in a house can often push the frames out of square, only a very small movement can result in a door or window sticking or the catches or locks not engaging properly. Cracked or broken window panes are also a give away

Earthquakes have a tendency to crack concrete (funny that) particularly on the roof and even more particularly along the roof ridges where the ridge tiles are cemented in place. You might not notice damage for a while but these things can become obvious rather quickly when it rains. Go around the house and check the roof ridges for cracks (a pair of binoculars can help a lot).

Walk around the house and tap the floor tiles, earth movements can often “pop” the tiles releasing them from the cement underneath. They will sound hollow if they have lifted.

If your building has stone cladding tap the pieces of stone to see if they have lifted away from the concrete beneath and look for movement along the joints.

Swimming pools and fish ponds that have not been designed or built properly are particularly susceptible. You may find the water level is falling more than it used to suggesting leakage somewhere.

Earth movement can also break pipes either underground or buried in walls, you might find damp patches or that your pump is running more than it used to.

In earthquakes most people are killed and injured from falling masonry. As was shown in this recent event poorly made building facades (immediately above entrances) present a major danger. It is also noted that in Indonesia “infill” walls (these are the sections of walls that “fill in” the sides of the building between the reinforced concrete columns and beams) are usually not tied into the main structure of the building and can crack or even fall out while the main structure remains sound.

It is well to remember that roofs are not very strong, they are only designed to withstand wind and keep the rain out. If anything falls onto a roof, such as a wall, it may well fall straight through onto anyone in the room below. We came across one such case from the recent event where a lightweight steel roof frame was badly damaged by a parapet wall that fell over onto a roof.

If you do notice something that you area not sure about call a structural engineer to assess the building.

We can only expect more earthquakes as the Australia plate dives underneath the Sunda plate we are sitting on the edge of (always troublesome those Aussies). Of course what we need are more earthquakes like this one, large enough to release the pent up energy in the earth's crust but not large enough to cause major damage or loss of life.

Copyright © Phil Wilson
This article or any part of it cannot be copied or reproduced without permission from the copyright owner.


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17 July 2017 Copyright © Mr Fixit,
Jl Bypass Ngurah Rai, Gg Penyu No 1, Sanur, Bali 80228, Indonesia
Telephone: +62-361-288-789, Fax:+62-361-284-180