Day 3 & 4: Manta, Crucita and Portoviejo- A Look at Mixed Use Buildings and Sharing Knowledge

On May 3rd, we went with Gen. Ruiz and Ing. Flores into the barricaded area of Manta, the neighborhood of Tarqui.  This area had the most damage and was a mix of large to small commercial buildings and hotels, plus multi family and single family houses (some mixed use).

Tarqui, Manta, Ecuador

Mostly residential street in Tarqui, Manta

Many of the small and medium sized buildings that had collapsed were already demolished and some were being taken down while we were there.

Three story building being demolished. Manta, Ecuador

Three story building being demolished. Manta, Ecuador

 

There were buildings with very different performance on the same block and the reason for the difference in performance was not obvious.  Additional investigation is needed to see really why some had collapsed and others did not.

 

There were several green-tagged residential buildings in the area – particularly along one street. Though one of the homeowners there was telling us that they didn’t know if the green tag for their house was correct because although the exterior looked undamaged, they said many of the walls inside were damaged.

Green-tagged houses in Tarqui, Manta.

Green-tagged houses in Tarqui, Manta.

Tuesday evening we presented a seminar with Ing. Flores in Manta, open to the public.  We spoke about our experiences in housing reconstruction following other earthquakes and Ing. Flores presented on the Construction Code.

Lizzie presenting in Manta

Lizzie presenting in Manta

 

On Wednesday we headed to Portoviejo and stopped in Crucita, a coastal town along the way.  Overall Crucita had very little damage compared to Manta to the south and Canoa to the north.  A local business owner told us that only 6 houses had significant damage.  Walter interviewed a builder there to find out about local construction practices.

Walter interviewing a local builder, Oriol, in Crucita.

Walter interviewing a local builder, Oriol, in Crucita.

We then visited downtown Portoviejo, the area in the city with the most damages.  There were not many 1-2 story houses, but some were damaged, particularly when mixed-use.  There were many taller, larger and mixed-use structures, which were damaged in many cases.

Damaged 4-story mixed use buildings in Portoviejo.

Damaged 4-story mixed use buildings in Portoviejo.

We then presented a similar seminar as the previous night with Ing. Flores, but in Portoviejo.

Juan presenting in Portoviejo at the Technical University of Manabi

Juan presenting in Portoviejo at the Technical University of Manabi

Day 2 (Part 2): Canoa and Jama- Analysis of Damaged Homes and Schools

After Canoa, we next headed north to Jama, another coastal town.  In Jama we selected a street in town and compared the building type and performance of each, one-by-one.  There were 7 houses, some with commercial space below.  Six houses were wood framed, 2-stories, and one was reinforced concrete, 3-stories.

Team in Jama on the street surveyed: Ing. Flores, Walter, Lizzie, and Juan

Of the wood framed, 5 had masonry infill at the ground floor and 1 had bamboo lath with plaster overlay at the ground floor.  Four had wood only walls at the upper level while two had mixed wood and masonry infill walls at the upper level.  In general of the wood-framed buildings, we saw the most damage (wall and partial roof collapse) in the upper levels of buildings where wood and masonry infill walls were mixed.  This is probably because the wood walls were not sufficient to resist the larger load imparted by the adjacent heavier masonry infill.  Houses with wood only walls at the upper level generally performed well, with minimal damage (some movement at the floor level at some column joints) except where it appeared the wood was deteriorated and not well maintained.

The concrete frame with infill building fully collapsed at the ground floor level (hinging at the ground floor columns) and the infill was damaged. It was not directly observable, but it was likely that the ground floor had more open area in the from elevation, creating a weak/soft story condition.

Concrete frame with infill - suspected soft/weak story collapse

Concrete frame with infill – suspected soft/weak story collapse

In Jama, we also observed some damages to schools – site wall collapse and building wall collapse.

In general it seems people have a more negative impression of the concrete buildings and are more comfortable with wood after the earthquake, because of the difference in performance and survivability.  We saw a comparative example on the ride back to Manta, when a 2-story concrete frame with infill police station was heavily damaged, and the adjacent wood housing across the street was fully usable, without damage.

 

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Day 2: Canoa and Jama- A First Look at Damaged Schools

This morning we met with Ing. Hermel Flores, owner of Hermel Flores Construcciones and former chair of the Ecuatorian Chamber of Construction, and General Florencio Ruiz Prado, Director of Citizen Security for Manta, in Manta.  We discussed our activities, the situation and the presentation they coordinated for us to give on Tuesday and Wednesday, in Manta and Portoviejo, respectively.

Build Change team with Ing. Hermel Flores in Canoa, Ecuador

Juan and Walter from the Build Change team with Ing. Hermel Flores in Canoa, Ecuador

Ing. Flores traveled with us next up north towards the epicenter.  The coast of Ecuador is in the highest seismic zone of the country.  There are RENAC sensors located up and down the coast which recoded the accelerations in the recent earthquake.  The records from these sensors are being retrieved and processed.  We’re looking forward to the report on those coming available soon to see how they compare with what we observed along the way.

We stopped in Canoa and checked in with the COE, the emergency operations committee.  They reported that 9 of 17 rural schools in the area collapsed or had significant damage and that both of the two urban schools were damaged and not useable.  Many of the collapsed buildings in town had been hotels, rather than houses, but houses were also significantly damaged.

We visited one of the schools in town, William Fletcher, with the municipal engineers.  It had three different two-story classroom buildings, all were reinforced concrete frame with infill.  There were also two seismically separate stair towers, with minimal damage.  One of the classroom structures, blue and white, had minimal damage and could likely be easily repaired and retrofit.  (Although, one of the damages was parapet collapse, which could be highly hazardous to students below.) The other two buildings were more heavily damaged, and one of them had noticeable residual drift.  The damages included failure of the ground floor columns at the base and at the top below the floor beam, failure and cracking of the masonry infill, and failure at the intermediate beam connection to the column.

You could see that the frame columns were smaller in the more heavily damaged buildings (green and yellow), and the infill was not covered in cement plaster as it was in the blue and white building.  These differences may have contributed to the difference in performance.

Many houses in the town were constructed of timber framing with masonry infill.  Another common housing type was concrete frame with infill.  We saw examples of damage in both and Walter interviewed several homeowners.

In one case, the house was timber framed with brick infill.  During the earthquake, the masonry failed at one side of the ground floor, the wall collapsed and the corner post became disconnected from the floor, causing the rear corner of the house to partially collapse.  The homeowner wants to rebuild his house in the same way, but with one exception – he would not use brick infill, but all wood walls instead.  He thought that would be less hazardous in another earthquake.

 

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Day 1: Guayaquil to Manta- A First Look at Damaged Houses

May 1st was our first full day in Ecuador, after landing in Guayaquil on April 30.  Our team has three members: Traveling from our Bogota office there is Juan Caballero, architect and Director of Programs and Partnerships for Latin American, and Walter Cano, structural engineer and Project Engineer for Colombia.  From the U.S./headquarters there is Lizzie Blaisdell, structural engineer and Director of Engineering.

In Guayaquil, we saw little evidence of an earthquake.  According to the preliminary report on the Instituto Geofisico website (http://www.igepn.edu.ec/) a strong motion sensor near Guayaquil, “AGYE” experienced a maximum ground acceleration of 23.04 cm/s2 (approx. 2%g) while another just east of the area, “AMIL” recorded a maximum acceleration of 51.04 cm/s2 (approx. 5%g).  As a point of comparison, the new Norma Ecuatoriana de la Construccion (Ecuadorian Construction Code) considers the seismic zone factor, Z, to be 0.4.  For a Type D soil, that would result in a peak ground acceleration of 0.48g for the design spectrum (475 year return period earthquake).  So the recorded motions indicate the accelerations were about 5-10% of the design basis earthquake for Guayaquil, fairly low.

We spent the day driving toward Manta.  In Guayaquil, the housing was generally taller than once we were out of the city.  The residential buildings were typically concrete frame with block infill, or confined masonry in some cases.

Ecuador- Confined Masonry Example

Guayaquil, Ecuador- Confined Masonry Example

As we drove further from the city along highway 482, the housing types became more variant.  Instead of columns and beams built from reinforced concrete construction, we also began to see houses that were heavy timber frame or even steel frame, with infill.  The infill varied too, from concrete blocks, solid bricks (often turned vertical on their narrow edge), or hollow clay tile.

We only started to see significant signs of earthquake damage as we approached Montecristi, a town just east of Manta.  However, once we arrived in Manta, the damage was evident and areas of the city were barricaded for safety.

Manta, Ecuador

Manta, Ecuador

We saw similar housing types in Manta as we had seen on the drive.  Several timber frame with infill houses were heavily damaged.  Probably the masonry did not have  good connections with the frame and it was also not strong enough to resist the earthquake – causing failure of the masonry and separation from the frame.  Sometimes it appeared that the collapsing masonry tore down other parts of the building with it, such as the roof or floor.

Manta, Ecuador - timber frame with infill house

Manta, Ecuador – Damaged timber frame with infill house

Separation between the different parts of the building due to poor connections between elements was a common type of damage observed.  The connections were not strong enough to keep the building tied together in the earthquake.

Several residential buildings suffered from soft/weak story failure.

We also saw failure or damaged front walls where they cantilever out over the facade below.  The vertical discontinuity this causes can create stress concentrations at the overhang and increase flexibility at the base of the overhanging wall – leading to cracking.

We see very similar types of buildings  to these from Manta everywhere around the world where Build Change works. It’s always hard to see communities suffering from these disasters. We hope these vibrant towns will be able to recover from this disaster quickly, while rebuilding safer, more resilient communities.

Follow our team in Ecuador.

Saving Lives through Retrofitting in Colombia

Click here for link to Autodesk Foundation video.

“We can build buildings to withstand earthquakes. The knowledge and technology are out there. We just have to make it accessible to everyone.” – Elizabeth Hausler Strand, Founder & CEO, Build Change

In Colombia, we are working with city governments, the private sector, and homeowners to repair and strengthen homes before the next earthquake strikes. Retrofitting saves lives by ensuring that houses will protect families and children from future natural disasters.

We started out retrofitting a single house in Bogotá, Colombia, to provide an opportunity for local training and to demonstrate feasibility. Jorge Prada’s family now lives in a safe house and he will help retrofit others.

In partnership with Caja de la Vivienda Popular (CVP), the Swiss Re Foundation, and RMS, Build Change is now launching a pilot retrofitting project that will reach 50 houses. We are currently training CVP staff and contractors in retrofitting, to build permanent local skills. Then, the retrofits will begin and our staff will support those projects with technical assistance in design and supervision of construction.

We look forward to making at least 50 families safe in the next few months, and many more in 2016.

Thank you to all our partners in Colombia, including the Autodesk Foundation and Micro-Documentaries for creating the video above.

Second Strong Earthquake in Nepal: Build Change Team Unharmed

A second strong earthquake struck Nepal on May 12, 2015. We are relieved to report that our team reported in and they are unharmed. The families in the small village they were in when it struck are also unharmed.

“We are all fine. At the time of the first M7.3 earthquake near noon, we were in a very remote village, Thulo Guan, Balthali, an hours’ drive from Kathmandu on a rutted, narrow dirt road along a cliffside. No one was hurt in this village.

We were standing on the 2nd floor of a relatively undamaged house (newer construction from about 2008) talking to the owner when the quake hit. I have never seen people fly down steps so fast once what was happening sunk in! I actually saw the (minor) out-of-plane movement of the stone and mud mortar wall (about 15″ wide) when I got outside. I’m happy to say that house is still fine and habitable after the earthquake and the aftershock.

We were still there a short time later when the M6.3 aftershock hit. A couple of already severely damaged houses collapsed further. The relatively undamaged houses remained intact.

Several resulting landslides on the road made leaving the village a bit tricky. We expect to encounter more landslides during our drive to Sindhupalchok, northeast of Kathmandu, to see how we can support the rebuilding process in that region.”

Our thoughts are with the families in other areas who lost loved ones to this second earthquake.

Community Education in Takengon, Indonesia

Over 150 adults and 100 children participated in our Better Building Material community event in Takengon, Indonesia in December 2014. We have been working with 200 local brick-makers, mostly women, to help them produce better quality bricks.

Houses and schools built with poor-quality bricks or concrete blocks are likely to collapse during natural disasters. Better bricks and concrete blocks make safer houses and schools.

We provide on-the-job training for small businesses that manufacture bricks and blocks to improve the quality of their products. We also offer business skills training in management, budgeting, and more efficient manufacturing techniques.

We conduct public outreach to encourage local communities to use these safer building materials.

To keep children occupied while their parents learned about safe building techniques and better brickmaking at this event, we held coloring, drawing, and writing contests.

Little 8-year-old Fatimatuz wrote about her experience in the 2013 earthquake that destroyed her home:

“My younger sister and I were playing a cooking game, and the earthquake happened. We ran to the door, but we could not open it, fortunately then my father carried both of us outside. After that we set up a tent. I have to be strong. It is really fun to sleep in the tent. There are 7 people who live in it.”