Learning from Earthquakes Damage: Non-Engineered Construction in Indonesia

The Indonesian non-engineered buildings construction mostly consists of masonry (clay burnt brick or rubble stone or concrete blocks) structures confined and / or unconfined. The construction of masonry buildings are not too complicated, therefore, it is widely used almost all over Indonesia. It is also known that masonry is relatively brittle and unless provided with reinforcement, or other suitable materials and built appropriately; such buildings are weak against earthquakes.

With the extreme pressures of a great demand for new masonry buildings together with a limitation on the resources available, including finance, knowledge, skills, and building materials, resulting in poor workmanship and poor quality of construction. The general tendency has been for the standards to fall year by year. World experience in damaging earthquakes has shown that these types of construction are dangerous to human life, often in a relatively small earthquake.
It is quite apparent that it will be difficult to do away with this kind of construction in seismic areas in developing countries, particularly for clay burnt brick masonry, because brick is relatively cheap, easy to produce and to transport, and masonry building is relatively easy to construct. The above facts have made masonry very suitable as main options for people to build houses. Therefore, the trend to build more and more masonry buildings is obvious.

In order to save lives during a large earthquake, Indonesia with millions of vulnerable non-engineered constructions and the recurrence of earthquakes almost every year, have to start implementing better techniques or methods in constructing masonry building to reduce the impact of earthquakes.

From an economic point of view, it is unreasonable to rebuild all the structures that cannot withstand when shaken earthquakes, although such an action is ideal. It should be carefully decided that whether to rebuild or merely strengthen. The ideal solution would be to discover some means and methods to improve the present construction and the related materials using available materials with local labor under minimal supervision and most suitable to the local culture. The main aim is to save human life; therefore, structures might be damaged when shaken by earthquakes, but does not collapse and kill people.

The book is based on the author's observations from surveys and documentations of past earthquake damages of non-engineered constructions in Indonesia in a time span of 50 years.