Engineer Suresh Hada, currently the Director of Robust Consulting Engineers Pty Ltd based in Melbourne, holds a Master of Engineering Science from University of Melbourne. In his over 35 years of experience in the engineering field, he has gained expertise in earthquake and blast resistance design, design of residential and industrial structures including smelter plants, solar and signage design, among others working at both national and international organizations. Nepal Live Today spoke to him on a wide range of issues including the recent Jajarkot earthquake, resilient infrastructure, and the concept of Building Back Better. Excerpts:
It is often said that ‘earthquakes don’t kill people, buildings do.’ How true was it in the case of the recent earthquake that hit Rukum west and Jajarkot districts in Nepal?
A slight modification to the saying could be “earthquakes do not kill people but improperly designed buildings do”. Almost all the buildings that collapsed in the recent Jajarkot earthquake were non engineered, meaning none of them had followed earthquake design principles. Therefore, the result was disastrous as predicted by research and studies.
Health posts and school buildings have been destroyed due to the Jajarkot quake. It seems we haven’t learnt much from the 2015 earthquakes. What would you say?
There have been several major earthquakes in Nepal even well prior to 2015. In each event, the government focuses on the reconstruction of the affected areas only. An effort to enforce earthquake resistant design for new constructions and retrofit the existing buildings in other areas should have been carried out as a long-term strategy for the nation.
By observing the photos of the destruction, it is evident that the health post and school buildings destroyed were not engineered at all. These structures might have been constructed before the earthquake codes came into effect. As I mentioned, retrofit policy on already constructed buildings shall also be brought into effect specifically for the structures that fall under higher importance levels such as schools and health posts.
‘In the past 500 years there has not been a big earthquake recorded or documented in the western region of Nepal. This seismic gap is worrisome.’
It is sad to see enormous casualties in each event, which could have been prevented, had earthquake principles been followed in the construction. In the past few years, awareness in earthquake design has increased among people in urban areas. As a result, they have been willing to follow the codes unlike in rural areas.
The government introduced new building codes following the 2015 earthquakes. But local bodies seem reluctant to enforce the code. What would you suggest?
The enforcement of construction codes in the government buildings has been observed to be more prominent but not in private constructions. The main reasons for this are cost impact to make the structure earthquake resistant and a lack of technical resources.
The National Reconstruction Authority (NRA) proposed a number of models to build earthquake resistant houses but local communities don’t seem happy with those models. What’s the reason? Have you or your company developed any alternative models?
As I mentioned, cost impact and lack of technical resources are the main reasons that local communities are reluctant to adopt these models. I think the government should initiate programs providing economic incentives for people who construct the buildings following earthquake design code and also use the policy to train more manpower in the construction sector.
Our company “Robust Consulting Engineers Pty Ltd” is involved in earthquake resistant design. However, it has not currently developed any building models. Nevertheless, if opportunities arise, its extension in the field cannot be ruled out.
The NRA had trained masons (including women) in the aftermath of the 2015 quakes. How do you see the possibility of employing them as trainers?
Training of masons is one of the most important steps that the NRA has taken. However, this has been more concentrated in urban and past earthquake affected areas only. Considering the entire country is situated in an earthquake prone zone, such training should be extended all over the country including in rural areas.
I feel employing experienced and trained people as trainers is one of the best strategies to overcome a lack of skilled manpower such as masons. Masons training was initiated by organizations such as NSET (Nepal Society of Earthquake Technology) over two decades ago. It needs to be followed at a government level and extended in the rural and remote areas as well.
Engineers say locally available materials should be used while reconstructing destroyed buildings. How feasible will that be? Is the use of concrete and cement necessary to build quake resistant houses?
It is true that locally available materials should be used for the reconstruction. As local materials are abundantly available, their use makes construction projects economically feasible and environmentally sustainable. Having said that, the traditional method of construction will need to be modified to make buildings resistant to earthquakes.
No doubt, cement and concrete are good construction materials but constructions using local materials such as stone, brick, mud, timber and bamboo can also make structures earthquake resistant if joint detailing is properly followed. It is also worth mentioning here that a small portion of cement when mixed with mud mortar can significantly enhance the strength of joints. Similarly, mud mortar walls can be tied by cement concrete bands to enhance the earthquake resistance of a building. Further use of galvanized steel members should be considered in the structures constructed with local materials. The use of steel is better because its mass is lower and its production is more environmentally friendly than the production of cement.
‘An effort to enforce earthquake resistant design for new constructions and retrofit the existing buildings in other areas should have been carried out as a long-term strategy for the nation.’
Scientists say there is a huge risk of a big earthquake in western Nepal. But most of the houses are made of mud and stone and are likely to collapse. What would you suggest?
In the past 500 years there has not been a big earthquake recorded or documented in the western region of Nepal. In earthquake terms, it is called seismic gap and it is worrisome. The seismic energy has not been released for a long period of time in the region, which increases the risk of having a major earthquake in future. We need to be prepared for this and take action to mitigate the potential enormous losses from future earthquakes.
Random rubble stone masonry walls in mud mortar are more prominent in constructions in the western parts of Nepal. This type of construction is vulnerable to earthquakes due to a number of reasons. First of all, the bonding of such walls is considerably weak compared to those constructed of bricks. Further, stones have greater mass compared to brick and other materials which attract more seismic forces. The constructions of these types should be assessed and retrofitted if necessary.
The government is said to be considering forming an NRA-like authority to oversee the reconstruction works in the quake affected districts of western Nepal. What would you say?
Yes, it is a good idea to form an authority to oversee the reconstruction works considering the massive scale of destruction. The aim of the authority should be to provide assistance to constructions and monitor the works as well. We will also need to simplify the bureaucratic procedure to speed up the reconstruction program.
Many see the latest earthquake as an opportunity to ‘Build Back Better.’ But the majority of the people are poor and are unable to afford constructing quake-resistant houses? What would you say?
The government should bring a feasible policy in this regard. Lack of funds/technical resources can be overcome by seeking assistance from donor/loan agencies. To attract these agencies, a proper mechanism to curb corruption should be in place.
There have been a lot of documents and detailing prepared since the Nepal Building Code was enforced. Now is the time to effectively implement them. This requires long term policy to be initiated at the government level.