Wednesday, January 30, 2013

Learning from Bukit Setiawangsa Slope Failure

SLOPE FAILURE AT Jalan Bukit Setiawangsa
TAMAN SETIAWANGSA KUALA LUMPUR
29 December 2012

Firstly I wish to record my heartfelt sympathy to the affected parties which comprise households and businesses within the vicinity of Jalan Bukit Setiawangsa.  Quite a number of friends and acquaintances had to move from their homes and business due to the tragedy.   
.
The engineered slope which has been standing tall - at 10 - 11 berms totalling over 50m high - since the early 1990s failed quite dramatically about 1000pm on Friday, 28 December 2012.  When I passed that area about then the bottom-most of what left of that section of the concrete wall, in the picture above, was still moving towards the road and we had to drive through the detour in front of the shops.  Thank you to the guards there who had quickly arranged cones to divert the traffic.
.
As of 30 January 2013, the developer has built gabion walls up to about 6 stacks [ about 6m high perhaps ] over the 4-lane road [ 2-lane dual carriageway with a median strip ] and being filled up with gravel and stones over a stretch of about 100m, as a temporary measure I have been advised, until a permanent solution is derived.   On top of the hill, the collapsed house has been demolished and the others appeared to being repaired and the exposed slope being covered with gunite, if I am not mistaken, which is a mixture of cement and sand with light-gauge steel  mesh.   Meantime, the road is closed indefinitely.
.
What are the lessons I learnt from this tragedy:

1. REMEMBER MAINTENANCE MAINTENANCE MAINTENANCE

Despite the numerous high-tech facilities available in Malaysia and having a pool of some of the smartest and experienced professionals, Malaysia-incorporated is still NOT ready for the GOOD MAINTENANCE IS ESSENTIAL MINDSET.   We are yet to sink it into our minds that to have facilities in good conditions we have to maintain them properly without exception.

From my understanding of the so-called engineered slope / retaining wall systems - and a number of articles in the newspaper quoting a number of geotech experts confirmed my understanding - the wall was designed with a periodical maintenance built into the life of the wall system.   

Hence, if maintained properly, the engineered slope should be standing there forever, God willing.

Until such time that we as a society is ready to the GOOD MAINTENANCE CULTURE, perhaps engineers and architects should design structures and buildings which require no maintenance and with no safety issues.

2. BEWARE OF CHEAP NOW BUT EXPENSIVE LATER SOLUTIONS

It probably was the cheapest option to construct the retaining wall with the engineered slope concept but somehow somebody forgot to evaluate the lifecycle cost of the engineered wall which required 6-monthly inspections and periodical maintenance cost for the whole of its service life.  It could probably be that had somebody calculated the costs of all the retaining walls options taking into account the actual lifecycle cost i.e. construction and maintenance cost over the the service life of the slope - like until the end of the world!, the engineered slope might not have been the best and cost effective option then.

We can only guess but it is probable that after a few years upon completion of the wall, and in this case over 20 years assuming it was built in 1992 as reported, just about everybody forgot about the need to maintain the wall periodically or the party which is supposed to maintain it found out that the cost of maintenance and/or repairs are very expensive and thus may have skipped the regular maintenance schedule.  Which may end up now as a cheap upfront cost solution but with an expensive total lifecycle cost.

3.  PROVIDE THE BEST SOLUTIONS FOR THE EVENTUAL USERS AND NOT JUST WHATS BEST FOR THE PAYMASTERS

Consultants, including me unfortunately, sometimes were too eager to please clients in order to land the lucrative and elusive professional fees and in this eagerness might have offered solutions which looked smart and cost effective then but they end up as nightmares to the maintenance team later or the eventual users.  In the eagerness to achieve max profits for our paymasters consultants may opt for solutions which may cost more to maintain later or, God forbid, end up with solutions which may risk or endanger lives of the eventual users.  We consultants should remember the amanah or trust put on our shoulders to build proper homes and buildings that should by right outlast us and many generations after us.

We can revisit the works of the Greeks and Romans to humble us consultants and admire how they had managed to keep their buildings upright and some in working order over the millennia [ from 1000BC etc ] with only low technology at hand - and basically with no maintenance [ granted there were restorations, conservations etc ].   Basically the Greeks and then the Romans clearly showed us that when done with a lot of thought given to and care put into them, structures and buildings could last quite a long time and maintained in good condition.   In comparison, our buildings generally last 5 to 10 years before things go wrong and that despite the high tech that we have today  [ or worst, they fail after the end of the defects liability period which may be between 1 to 3 years depending on the contract! ].   The ready-to-wear and disposable item concept are not suitable for the construction industry as buildings lifecycles are generally in decades.

Building consultants, I am but sharing this reminder to myself, should use the latest technologies to improve the lives of people now and in the long run.   Experiments must be done but we should keep experiments in laboratories most of the times and not experiment on somebody else's lives, livelihoods and properties.