Degenkolb Chile Team 2 left the US from 4 different cities on Tuesday March 16 – Stacy Bartoletti from Seattle, Kent Yu from Portland, Daniel Zepeda from LA, and Mike Braund from San Diego. We all met up in Atlanta and flew from Atlanta to Santiago and then from Santiago to Concepcion. The travel was generally uneventful with the exception of very short connection times. 3 of the 4 of us ended up running through the airport in Atlanta to catch our flight and we all ran through the airport in Santiago to catch our plane that was held just for us to Concepcion.

Upon arrival in Concepcion we were met by our tour guide Chris and a film crew from Vancouver BC developing a documentary for the Discovery Channel Canada. Mark Mills the producer and Kevin Mills spent the day with Degenkolb Team 2 and Mark Pierepiekarz from Seattle looking at the earthquake impacts in downtown Concepcion. It was a very productive day. We started the day by getting onto the roof of a 16 story apartment building. This allowed us a bird’s eye view of all of Concepcion and started the day with incredible hospitality from the people of Chile. We had no reason to be allowed access to the roof of this particular building other than we asked and building manager gave us a personal tour and also dug out drawings of his building for us to review.

Roof Top Photographs 1 and 2.

Following our roof top view we visited the now famous Alto Rio building that collapsed at the first story and toppled completely over. We spent significant time at this site and were able to gain access to the building by a professor from Chile that Daniel met. There will be much to learn from this collapse as more details become public but it appeared to us that it had discontinuous shear walls on the east side of the building that failed and caused it to completely overturn in one direction.

After the Alto Rio Building we looked at several other buildings including a new 25 story concrete shear wall apartment or condominium building that had severe damage to a couple of shear walls at the boundary elements. It appears as though typical construction of shear walls in Chile does not include any special confinement steel at the boundary elements. We also progressed to the also soon to be famous O Higgins Building. This is also approximately a 22 to 23 story building that is a total loss due to structural damage to exterior concrete shear walls and partial floor collapse. The building appeared to have torsional irregularities at the upper levels and higher mode effects. It was also very interesting to note the large amount of debris that fell from the building right over the main entrance. This building was completed in 2009 and was not yet fully leased as office space.

One final observation from day 1 was the large amount of damage to new and very modern buildings in Concepcion. Several new buildings that were not even fully occupied performed very poorly while others performed very well. It is not yet apparent why there was such a discrepancy in performance but it is clear that the impacts of the earthquake and inability to recover in a quick manner would have been much greater if these buildings were fully occupied. Where would all of these tenants have gone and how would the community be resilient without their support in recovery?

Concepcion

Bldg ID 3-13
Concepcion Hospital (36⁰ 49′ 30″, 73⁰ 02′ 16″)
Three separate buildings, construction dates 1943, 1987 and 2009, make up the main buildings of the largest hospital in Chile. This 1000 bed hospital campus also has support buildings such as the central plant, dining building, MRI and miscellaneous small bungalows. When the earthquake hit, the hospital lost functions to radiology, central processing, ICU, and the boilers in the central plant. Unlike the hospitals in Curico and Talca, this hospital, although closer to the epicenter, performed much better.

The 1943 building, a 6-story concrete frame with brick infill did not sustain too much damage and performed quite well. There were some brick infill panels that sustained damage, but did not fall out. In each operating room, a crack was continuous around the entire wall/ceiling interface. A large number of glass in the windows broke but the remainder of nonstructural damage was relatively minor.

The 1987 building, a 6-story concrete frame with brick infill, performed quite well and had minor damage. However, the bridge structure connecting to the 5th and 6th floors of 1943 building sustained significant damage at the connection interface. Nonstructural damage in the ceiling occurred in the link bridge. The building was abandoned due to the water leak and flooding of the floors below.

The newest structure, a 6-story concrete shearwall building, was designed for a magnitude 9.5 earthquake. A link bridge structure connected to the 1943 building. The two structures performed very well. Only 11 ceiling tiles in the entire hospital fell. ICU was relocated temporarily to the bridge structure after the earthquake.

The central plant, a one-story steel butler framed structure, did not sustain any structural damage. The boilers were off-line except for one, but the anchorage was adequate. A tank elevated on a steel frame shifted during the earthquake and the pumps were disengaged. A make-shift temporary pipe brace was installed in an attempt to prevent future movement.

Tsunami Damage in Talcahuano

On Friday morning we visited the small fishing community of Talcahuano that suffered severe devastation due to the tsunami. The town is not very far from our hotel. Even though we arrived almost two weeks after the earthquake and tsunami, the evidence of destruction is still pretty evident. Cleaning activities are proceeding but it will take a long time for things to get back to normal.

• It appears the water reached a level of 4 to 6 ft. on average, but the water mark on other buildings was higher than that.
• Many fishing boats were tossed around pretty far into the town. The fishing boat shown in the pictures with some of us was probably 300-500 ft. from the ocean.
• We visited a large fire station that is fairly close to the water. The building was a “community center” that included a ballroom and sleeping quarters for three companies or battalions. Remarkably, the building suffered minor damage. The structure consists of several additions but it is a concrete building for the most part. There is a large open atrium built with a steel space frame. Damage was mostly to pounding due to inadequate seismic joints, stairs separation from the supports, cracking of infill masonry walls, cracking of beam-column joints and nonstructural damage.
• The next significant structure we visited is “La Tortuga” (”The Turtle”), which is a medium size sports arena adjacent to a multi-story concrete building. The arena was built with concrete columns and beams. The roof is very interesting since it is made of steel beams with a system of tension rods. In addition, the diaphragm appears to be plywood supported by a grid of wood blocking. There was only minor structural damage consisting of some concrete cracking due to pounding. Water flooded the arena and at the time of our visit, the water level was still about 2-3 ft.
• We also visited a school that faced the ocean directly and had several phases. The older portion of the school was under renovation and there is also a new wing under construction. In general, the older portion did fine except for some URM damage at the upper level. The new construction showed cracking of concrete shear walls. Interestingly enough, some of the detailing and quality of construction in general wasn’t of great quality.
• Next was a large shipyard where the Chilean Navy has its ships and submarines built. There are large dockyards and maintenance/storage buildings. Vintage of the buildings is fairly old with some concrete buildings dating back to 1930. There was significant damage to some buildings but the most dramatic damage appears to be related to the partial failure of the seawall.

Bldg 3-13
University Andres Bello (36⁰ 46′ 46″, 73⁰ 04′ 33″)
Four-story private university with one older wing and a newer wing under construction. On the picture of the model, it represents one half of the main wing and one half of the longest of three fingers. The rest of wings are yet to be built. The main entry has a large cantilevered overhang supported by concrete braces. There is a lot of mass at the cantilevers with a 3 story concrete wall at the tip of the cantilever. The structural system of the building is a concrete moment frame in both directions in the newer wing and concrete shear walls in the older wing. The concrete moment frame portion had a lot of exterior glass damage. The entire building façade is a storefront system. Unlike the practice in CA, the glass does not sit inside a mullion shoe but is epoxy glued to the face of the storefront so that you don’t see the mullions from the outside at all. Bad idea as evidenced by the damage to the glass. The other concentration of damage was at the concrete stair that is approximately in the middle of the new portion. Our conclusion was that the stair acted as a huge brace and attracted most of the load and the damage. The building was life safe, the Chilean code requires a 1.2 importance factor for university buildings. Another interesting observation was the cantilever end was sloping down about 5%, the contractor told us that they built it 2″ up.

Bldg 3-14
University de Concepcion (36⁰ 49′ 49″, 73⁰ 02′ 12″)
This is a beautiful large university in downtown Concepcion. We saw a 3-story steel braced frame building (chevron), very regular about 50 ft x 175 ft in plan with 4 braced frames in each direction. The building houses the Civil and Systems Engg. Departments. The Columns are 12″ tubes, beams are all 21″ channels or a combination of channels. The building did not have any damage or signs of yielding in the frames or connections. Just next to it was a similar building a few bays longer that was completely burnt except for the structural frame. We were told that this was a chemistry building where the contents caught fire after the earthquake.

Hualpen

ESSBIO WASTE WATER TREATMENT PLANT
(36⁰ 48′ 21″, 73⁰ 06′ 19″)

We arrived at the plant around 6 PM on Friday. The plant manager was very happy to show us the plant and the damage to his structures. The plant has two primary treatment tanks and three secondary treatment tanks. The primary tanks performed well and are fully operational. The secondary tanks failed and the contents spilled into the Bio Bio River. The failed tanks consist of four reinforced concrete segments with no structural connection at the joint. During the earthquake the segments shifted causing the joints to open creating an 8 inch gap between the segments. The bridges connecting the inner to the outer ring also shifted and are close to losing their support. The final chlorine treatment concrete segments also shifted and caused a gap. The support buildings and solids tanks performed well with no noticeable damage. The primary treatment tanks performed well due to their smaller size and concrete ring beam around the top of the tank. The equipment and piping was generally well anchored and performed well. The piping damage occurred at the piping joint with the tank due to the lack of flexible joints. Finally, we noticed that at least portions of the plant were built above an old dump site.

Video footage taken at the Essbio Waste Water Treatment Plant(below)

Degenkolb Reconnaissance team 1 - Chile Earthquake 2010
Left to Right: Roger Parra, David Gonzalez, Anuj Bansal, James Liu

Video footage of city of city of Concepcion (below)

Video footage of demolition (below)

Concepcion

Today, we started the day at the downtown area of Concepcion after a quick breakfast at the hotel. Luckily, our drivers made it to Concepcion. Traffic is heavy, a sign that things are slowly going back to normal. We were looking at a swimming pool on the 2nd floor of a condo building when we felt the aftershock just before noon. At the epicenter in Libertador O’Higgins, it was a 6.9 but it didn’t feel as strong in Concepcion. We finished looking at buildings around 2 pm and couldn’t find suitable places for lunch so we decided to head back to the hotel to see if the restaurants by the shopping center across the street were open.. bad idea! Because of the aftershock, a tsunami warning had been issued and it took us about 1.5 hours to get back to the hotel only to find the shopping center closed. We made it back to downtown in the mid-afternoon and had an opportunity to see many other buildings, including ongoing demolition of condemned buildings.

Today was Anuj’s birthday so we had agreed to do something a little special after our return. Red wine and torta (cake) after a quick dinner along with our Happy Birthday singing ended the day.

Based on what we have seen, it is likely we will change our itinerary slightly; and probably stay in Concepcion for the rest of our time here instead of going back to Santiago tomorrow. There is just too much for us to see here!

Bldg ID 3-11.1
Torre O’Higgins 241 Office Building (36⁰ 49′ 47″, 73⁰ 03′ 19″) (below)

• This modern towering office building of approximately 20 stories suffered extensive damage. There is risk of collapse and we had to photograph the building from a block away. The tower was inaugurated in mid-2009. Unfortunately, there appears to be a trend of severely damaged buildings constructed in the last few years.
• The structure has at least 3 levels of underground parking and 20 stories above ground. It is a reinforced concrete shear wall building with setbacks on at least two sides at about. Some of the shear walls are discontinuous landing at columns on two sides of the building.
• The building suffered a torsion irregularity and perhaps a soft-story condition at level 14 or 15. In addition, a regular pattern of spandrel beam shear damage can be observed. These conditions are observed on the East elevation only since the West elevation has a more regular shear wall layout. After the piers failed in shear, they lost the load-carrying capacity and a soft-story developed.
• The West elevation presents only minor damage.

• A reporter mentioned that this new apartment building, about a block away from Torre O’Higgins, has substantial damage in the lower levels. The access has been blocked off but we were able to observe shear failures in the concrete shear walls, in the East-West direction.
• The building was opened in December 2009 and suffered vertical deformations, according to one of the tenants that indicated the doors stuck after the earthquake and people couldn’t evacuate.
• The building is a reinforced concrete shear wall building with approximately 22 stories.There are several wings forming the floor plan, with setbacks about halfway up.
• The observed exterior damaged concentrated in the lower 2-3 levels with shear wall boundary element compression failure being the predominant damage. In addition, some widespread couple beam cracking in shear can be observed in some of the spandrel beams between shear walls. An interesting observation is that some of the vertical reinforcing in one of the boundary elements snapped or fractured.
• A homeowner indicated that there is severe nonstructural damage and that the owner has indicated they will repair the building. They were to be allowed to go inside today to retrieve personal belongings.

• The building is a two-story reinforced concrete building with concrete diaphragms. Substantial cracking of some of the shear walls, predominantly in the East-West direction, is present. In addition, some of the concrete roof slabs have cracking around the perimeter. This appears to indicate that the vertical acceleration component was very strong.
• There is some evidence of pounding in the North-South direction since there are no joints between the fire station and the adjacent buildings. Several of the buildings along this block may have worked together.
• The building has an open front to house the engine bays. The engines are not housed inside the fire station for now for fear they may get trapped in an aftershock. The firemen are now sleeping on tents on the street.

• We were invited by a homeowner to come in and take a look at the building. The building is a 15-story shear wall structure with a couple levels of parking garage underneath. There doesn’t appear to be significant damage from the exterior. However, there is some damage in the staircase walls, garage shear walls and also in the lintel beams above most of the doorways. Some cracking was also observed on some interior concrete shear walls.
• The elevated pool is in a separate structure. We were walking around the pool when we felt the aftershock. No major damage occurred as the ground shaking in Concepcion was relatively low this time.

• 15-story above ground plus 3 underground parking garage levels. The structure is a concrete shear wall building, opened in 2009. The building serves retirees and provides services like: dental, medical clinic, spa, financial services, conference center, etc. There are no ramps to access the garage levels but rather a car elevator is used.

• The building has regular openings on three sides, the exception being the front side which is completely open to accommodate the storefront façade. The building is generally rectangular in footprint and has shear walls around the stair and elevator cores, and three perimeter walls. Metal panels and storefront form the skin of the building. There is a stiffness concentration on one side of the building which induced a torsional irregularity.
• One of the side walls exhibited severe damage at the third floor, apparently due to torsional effects. The amount of reinforcement appears to be similar to that of comparable buildings in the US. The aggregate provided good interlocking and the concrete of quality is good. The rebar detailing is generally good, with the exception of the 90-degree hooks for the horizontal bars that slipped loose. The floor dropped a few inches in all levels above the third level in the area adjacent to the damaged shear wall. The contractor representative indicated they were planning to cast a new 32-inch exterior concrete wall full height and then remove the existing damaged wall.
• Other structural damage included cracking in some of the interior core shear walls and spandrel beams.
• Nonstructural performance was generally good with the most severe damage consisting of one or two elevator counterweights rotating themselves out of the restraints and slamming against the doors. One mechanical unit that was not attached from its platform dislodged and fell. Ceilings performed a little better in this building that in those observed before. Some windows and door glazing broke but in general performed in a life-safety manner.
• At the end of our tour, the property manager gave us access to the original drawings in electronic format.

• 17-story concrete shear wall building. Shear wall arrangement appears to be in a cruciform layout of 2 walls in each direction. Compression failure of boundary elements was present throughout the height of the building. Most of the damage is in the East-West direction.



Miscellaneous Buildings
We observed multiple buildings from different vintages and structural systems with different levels of damage, ranging from minor nonstructural damage only to imminent collapse. Demolition of unrepairable buildings is proceeding very fast and haphazardly at times. We also took some close-up pictures of the damaged silos mentioned in log #4.

Throughout the day there have been at least nine aftershocks ranging from 4.9 to 5.5. Stay tuned for more tomorrow!

]]> http://www.degenkolb.com/2010/03/13/day-5-report-on-chile-earthquake-2010/feed/ http://www.degenkolb.com/2010/03/11/day-4-chile-earthquake-2010-video-footage-of-alto-rio-apartment-building/ http://www.degenkolb.com/2010/03/11/day-4-chile-earthquake-2010-video-footage-of-alto-rio-apartment-building/#comments Thu, 11 Mar 2010 23:16:12 +0000 James Liu http://www.degenkolb.com/2010/03/11/day-4-chile-earthquake-2010-video-footage-of-alto-rio-apartment-building/

Day 4 - Chile Earthquake 2010 - Video footage of Alto Rio Apartment Building
Bldg ID 3-10.2
Alto Rio Bldg (36⁰ 49′ 41″, 73⁰ 03′ 41″)
This concrete apartment building built in 2009 (currently not shown on Google Earth) has been strewn across all media channels. When we arrived, we were shocked and in awe of the devastating force this earthquake produced. Survivors were giving testimonials of their earthquake and survival experience. Our tour guide was very sad and on the verge of tears after seeing the site in person. The 16-story structure, with 2 levels below for parking housed approximately 80 tenants. There were approximately 8 fatalities. The search and rescue effort ended yesterday with the last victim found. The lateral system consisted of shear walls in both directions. It is not immediately clear how the building failed due to significant search and rescue efforts that may have increased the amount of damage to the structure (holes cut into slabs, adjacent soil excavated, various elements leaning on the wall, etc.). It appears that the building failed in shear at the base. The structure toppled over and broke in half and went through the basement slab of the adjacent building site (the foundations and 1st floor slab were completed for another apartment building of the same design on the adjacent site). We observed the 8″ thick shearwalls had #3 bars at 8″o.c. with 4 #7 boundary bars typically. A neighboring building of similar construction was still standing.









]]> http://www.degenkolb.com/2010/03/11/day-4-chile-earthquake-2010-video-footage-of-alto-rio-apartment-building/feed/ http://www.degenkolb.com/2010/03/11/day-4-report-on-chile-earthquake-talca-and-concepcion-chile/ http://www.degenkolb.com/2010/03/11/day-4-report-on-chile-earthquake-talca-and-concepcion-chile/#comments Thu, 11 Mar 2010 22:07:22 +0000 James Liu http://www.degenkolb.com/2010/03/11/day-4-report-on-chile-earthquake-talca-and-concepcion-chile/

Talca, Chile
photos by James Liu

We apparently ended up in a hostel….yes a hostel by the name “Casa Chueca” which in Spanish means “Crooked House”. There may have been a little miscommunication from the tour guide (”hotel” I guess sounds close to “hostel”). Apparently, there were not too many places available for stay. The amenities were adequate and the owners/staff were very warm and friendly. We made it through the night in the adobe structures, got up at 7am and began our trek to see another hospital building we heard that was damaged severely.

Bldg ID 3-10.1 Talca Regional Hospital (35⁰ 25′ 35″, 71⁰ 38′ 47″)
Not unlike our medical centers, the hospital we visited was a collection of various buildings of different vintages. Some of the hospital functions were relocated to the adjacent medical clinic. Roger and David once again convinced the medical director to allow access for us to observe the damage. The damage observed was severe, but did not appear as bad as the hospital we observed yesterday in Curico.

1937 and 1950 Building
The oldest structure (started as a 40 bed hospital) was 4 stories, rectangular in shape with a concrete frame and infill hollow brick. There was a pitched roof supported by steel trusses. Concrete slabs supported by concrete beams were typical floor systems for the lower levels. The roof diaphragm did not appear to be connected to the transverse walls. The worst damage occurred at the 3rd story where the masonry partitions were falling into patient rooms. There was no out-of-plane support at the top of the walls. Surprisingly, there was little or no structural damage at the lower stories. Throughout the hospital, heavy lath and plaster ceilings fell from the ceiling and created hazards to walk through. Electricity was out. The OR’s were on the upper floors…exam lights and gas columns performed relatively well. These two structures were planned for demolition to make room for a replacement hospital, but the earthquake helped accelerate the schedule.

1990 structure (620 bed hospital inclusive of original bldgs)
The newest hospital structure, a 4-story concrete shear wall building was rectangular in shape with a lightwell in the middle. From our observation, it appeared to have sustained very minor superficial damage. However, there was a small portion of the hospital that suffered damage and was not in use. There were two seismic joints in the structure with MEP lines designed to accommodate movement at the joints. The lights were all anchored with vertical safety wires. However, we noted a large pile of lights sitting on the corner of the stair. It appeared that some of the support wires broke. Ceiling tiles were down, but the ceiling tile support systems were braced with wires, but no compression struts could be seen.

Clinic
The Clinic was a steel structure, 3-story in height with a steel braced frame lateral system. Quite a number of brace connections showed signs of distress. Gusset plates warped, bolts slipped. Some of the tube steel braces bowed out of plane, but no buckling occurred. The brace frames discontinued at the upper floor suggesting a cantilevered column lateral system. The floors are constructed of concrete slab over metal deck. The roof appeared to be OSB over light gage steel framing. In addition, horizontal X bracing was observed at the roof diaphragm.

In general, the older portion of the hospital performed well. The behavior would be categorized as what the expected performance of an SPC 2 hospital building. Irreparable damage, but life preserved. No patient was killed during the earthquake. The newer structure definitely fit the immediate occupancy characteristics, with exception of the one area that was damaged.

Other Buildings
In addition to the hospital, we noted some silos that had damage. Many roads had been damaged.


Concepcion

On the way to Concepcion, our van ran into technical difficulties. The engine overheated and we pulled over. James and David were trying to be mechanics, but no luck. The drivers flagged down a passing bus from the same tour company and we were on our way again.


We made to Concepcion around 2:15pm. After lunch at 3pm, we began our trek to observe the apartment building that received the most media attention. Walking around the site, we met the 3-star general appointed by the Chile president to investigate the building collapse as well as maintaining the curfew in the city. We continued investigating neighboring buildings that actually performed quite well from the earthquake. Since a military curfew was in place, we returned to our hotel at 8:00pm (our hotel only has water for 1 hour between 7:30pm to 8:30pm).

Bldg ID 3-10.2
Alto Rio Bldg (36⁰ 49′ 41″, 73⁰ 03′ 41″)
This concrete apartment building built in 2009 (currently not shown on Google Earth) has been strewn across all media channels. When we arrived, we were shocked and in awe of the devastating force this earthquake produced. Survivors were giving testimonials of their earthquake and survival experience. Our tour guide was very sad and on the verge of tears after seeing the site in person. The 16-story structure, with 2 levels below for parking housed approximately 80 tenants. There were approximately 8 fatalities. The search and rescue effort ended yesterday with the last victim found. The lateral system consisted of shear walls in both directions. It is not immediately clear how the building failed due to significant search and rescue efforts that may have increased the amount of damage to the structure (holes cut into slabs, adjacent soil excavated, various elements leaning on the wall, etc.). It appears that the building failed in shear at the base. The structure toppled over and broke in half and went through the basement slab of the adjacent building site (the foundations and 1st floor slab were completed for another apartment building of the same design on the adjacent site). We observed the 8″ thick shearwalls had #3 bars at 8″o.c. with 4 #7 boundary bars typically. A neighboring building of similar construction was still standing. Click here to view video footage of the site.


Bldg ID 3-10.3
Metro Control Station (36⁰ 49′ 47″, 73⁰ 03′ 37″)
This structure was located southeast from the Alta Rio Bldg, approximately 1 block away. Unlike the Alta Rio, the structure performed very well for this earthquake. The building function is to provide support for all metro transportation routes. This station was very interesting with multiple types of construction. The overall exterior “shell” consisted of steel roof trusses supported by steel brace frames. Underneath the “shell”, the structure consisted of a two-way concrete frame system with columns extending up and to provide gravity support for the trusses. A third steel brace frame structure is interconnected, but seismically separated, to the concrete portion and also extends up to support the overhead trusses in the “shell”. This building did not have an observable structural damage. There was a lot of nonstructural ceiling damage that was typical on all floors. The data control equipment, the critical element for operation of the metro, was damaged from the shaking. This building is shut down and currently not in operation. As a result, the metro system is still down. They plan to be back up and running in April. Coincidentally, the last victim in the Alta Rio bldg actually worked in this building.


Bldg ID 3-10.4
Ministry of Public Works Bldg (36⁰ 49′ 47″, 73⁰ 03′ 37″)
Two buildings down, we found another very interesting structure. From a distance, the structure was very prominent and definitely caught our attention. The building was approximately 6-stories tall with brace frames and bolted moment frames at the lower level. The brace frames only occurred at exposed lower levels and the bolted moment frame continued as the lateral system for the remainder of the structure. There is a basement where the brace frames and moment frames continue down into. Between the two buildings, a seismically isolated steel frame structure exists providing the interconnection and access to the all floors (stairs and elevators). We met the chief of public works who gave us a tour of the entire building. He gave us an overview of how they design and construct public buildings, which also includes school structures. The building performed very well with very minor damage (ceiling tiles falling, partition walls leaning, pounding between the structures).


We are now staying at the Holiday Inn in Concepcion. We will be here for a number of days and continue our reconnaissance. Until the next blog….

]]> http://www.degenkolb.com/2010/03/11/day-4-report-on-chile-earthquake-talca-and-concepcion-chile/feed/ http://www.degenkolb.com/2010/03/10/day-3-report-on-chile-earthquake/ http://www.degenkolb.com/2010/03/10/day-3-report-on-chile-earthquake/#comments Wed, 10 Mar 2010 22:39:12 +0000 Anuj Bansal http://www.degenkolb.com/2010/03/10/day-3-report-on-chile-earthquake/

David Gonzalez and James Liu finally arrived on Tuesday morning. We were anxiously waiting for their arrival to head south to the epicenter. We gave them time for a quick shower and breakfast before we hit the road. Our plan is to go to Talca (about 250km from Santiago) and 100km due west from the epicenter. We had heard there was significant damage in Talca and was also a convenient halfway point to Concepcion. We first head to the Enea area of Santiago, which is the industrial area just south of the airport where we had seen a lot of damage the day before. We wanted to give David and James a quick flavor so they could feel they hit the ground running before the long drive.

Bldg ID 3-8.5 Precast Concrete Warehouse (33⁰ 25′ 57″, 70⁰ 46′ 40″) Trial Clothing Warehouse
This is the same warehouse Roger & Anuj visited yesterday. We took a closer look at the wall panels, all stacked neatly on the ground. We noticed the wall panels were approximately 9″ thick with approx. 4″ of Styrofoam in the middle, except at the edges which had a 9″ flush pilaster element with 4 bars. Nice way to reduce weight, the wall spans horizontally to the edges and then up &down at the edge pilasters. Our conclusion is that this building has no real lateral system. The precast beam column connections are gravity only. The wall panels had no shear transfer mechanism. Possibly some cantilevered action in the columns may have saved the building.


Bldg ID 3-9.1 Confined Masonry Warehouse, Ceva (33⁰ 25′ 39″, 70⁰ 46′ 28″)
This is a confined masonry structure. We had seen parapet collapse on the back and front and wanted to get a closer look. After much negotiation with the owner/supervisor and turning down a request for a report, we were let into the building. The warehouse was not in use but still had empty racks that were tied together, braced and bolted and did not move an inch. The walls are 40 ft tall with 16″x 40″ concrete pilasters at 16 feet on center. Smaller concrete beams run horizontally between the pilasters at every 8 ft up. URM brick fills in the space between the concrete members. Long steel trusses spanned from pilaster to pilaster across the width of the building. They had a bearing seat on the pilaster and looked like 4 long bolts thru a base plate into the pilaster. Smaller trusses supported the front and back walls but not at the pilasters, rather in between. They had a end plate with bolts into a small concrete element in the walls. These bolts were short and had pulled out separating the wall from the roof leading to collapse. The rest of the system held together fairly well. The roof diaphragm had cross bracing comprised of double angles. Most of it held up well except some distress in a couple of spots. Every single light fell down.


Bldg ID 3-9.2 Curico Hospital (34⁰ 59′ 24″, 71⁰ 14′ 09″)
We had been wanting to see a hospital and finally we found one. The only hospital in a town of 100,000 and shut down after the earthquake. We could see a concrete frame structure with brick infill, 4 story tall, rectangular shape with center courtyard opening. The hospital had been moved into an adjacent newer clinic building. We were allowed to go in and greeted by the hospital director. We sat in his office and talked for about 15 minutes. Roger turned on his charm but the director seemed only too glad to see us. However, he said that the hospital had been evacuated and closed off by the military. The military had a field hospital set up in an empty lot next door and we were granted an audience with a 3 star lady lieutenant. After more sweet talking we were provided a sergeant escort to take us inside the hospital.The outside certainly showed damage but the inside was another story. A complete disaster. A number of the concrete columns had shear failure to the point that all the concrete had spalled off. They were 24 in x 24 in with 16 #8 bars and #3 ties w/ 90 degree hooks at 8″ oc, that opened up. Not bad compared to what else we had seen before but not enough. The concrete aggregate was large and river rock, not ideal. The stairs were near collapse, debris blocked egress paths and all the patient rooms and pre and post op rooms were completely trashed. The cabinet contents were all on the floors. We were taken up to the 4th floor which had the op rooms. The gas columns were still there, but the surgery lights had been removed. Although we could not see above the ceilings, we could see the ceiling suspension plates similar to what we would spec. Lights in the egress path appear to be intact. In an adjacent room the exam lights were still there and did not show signs of damage. Obviously someone paid attention to this aspect. There were also broken fire lines and water damage in some areas. Due to the amount of damage to the hospital structure we did not make a trip to the roof to observe the conditions of the MEP units. The vertical LOX tank outside at the ground level appeared to be anchored adequately. We were told that it was a 200 bed hospital built in the 1970’s that sustained some damage in 1985 which was patched up. The Univ of Chile had done a study indicating that the hospital was at high risk of significant seismic damage. The director told us that they were planning a replacement hospital but had not gotten it started yet. They have been promised a temporary 200 bed hospital by the govt. of Chile in 6 months to provide badly needed services to this town. As we had walked through the clinic first floor earlier, we could see that they had beds set up and every bed was taken. Apparently, nobody died or got seriously injured, the 40 critical patients were moved next door to the clinic and have since gotten another 60 patients from earthquake related injuries.


Bldg ID 3-9.3 Plaza de Armas in Curico(34⁰ 59′ 06″, 71⁰ 14′ 20″)
The plaza contained several different buildings closely spaced together, some with significant historic facades. Most of the façade elements were adobe and URM, tied back to the structure and had dramatic failures. A church built in 1743, was damaged previously, subsequently repaired and now damaged again. The tower portion was damaged and numerous cracks appeared throughout the structure. Brick elements peeled away from the structure and fell to the ground. The entire plaza had been barricaded off.


Bldg ID 3-9.4 Rio Claro Bridge structure(35⁰ 20′ 33″, 71⁰ 34′ 26″)
On our drive down to Talca, we noted many bridge structures with damage to the abutments. Most were still in operation. However, there was one with a dramatic collapse. The construction of this specific bridge appear to be a masonry arch structure.


We arrived in Talca late in the day, almost a 5 hour drive. Tonight we are staying at a bed and breakfast outside town and owned and operated by a migrated Austrian Family. They tell us that the new hospital in Talca (built a couple of years ago), had a major collapse and is going to be demolished. We hope to visit the hospital tomorrow morning. For now, as they say in Chilean, Ciao Ciao or Chao Chao (Bye Bye).

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