MEP Forensics

MEP Forensics

For the second year in a row AE 537  is pleased to host a Visiting Practitioner Lecture on MEP Forensics.  The session was presented by John T. Boyer, Sr., P.E., Principal and MEP Leader of Thornton Tomasetti (TT).  Mr. Boyer presented an overview of forensics work at TT with an emphasis on MEP forensics including touching on Cause & Origin Investigations, Expert Witness / Litigation Support, Thermal Imaging, Investigation Tools and Forensic Information Modeling (FIM).

The presentation included a number of mini-case studies of projects ranging from the recreation of MEP drawings and building models in the aftermath of a major fire to damage to a HVAC water riser piping system (FIM project) to damage to the the current WTC Towers as a result of  brackish water inundation during CAT-90 Sandy.

As Architectural Engineers and others interested in building related failures of all types you will encounter MEP failures of many kinds.  For example, many fires are electrical in origin and you will deal with the aftermath even if you are not charged with the cause and origin investigations.  A common MEP failure issue in residential construction is related to  PEX Plumbing Failures available on Failures Wiki under Systems Failures.   Students are encouraged to share their personal experiences, to discuss the interdisciplinary nature of forensic consulting and to research and discuss other MEP type failures including comparing them to the ones discussed by Mr. Boyer for similarities or patterns.

One document of interest on this topic that also contains other resources is the Hurricane Sandy – Lessons Learned from FEMA Mitigation Assessment Team (MAT) summary slide show.

 

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45 Responses to “MEP Forensics”

  1. Mehrzad
    November 15, 2016 at 8:55 am #

    Chapter 10 of “Forensic Engineering; Damage Assessments for Residential and Commercial Structures” book talks about water infiltration into basements and describes how power failure (often due to storm), improper installation, and mechanical failure of sump pumps could result in the pump not performing. The sump pump systems are usually placed in the basements and guide the water to the subgrade drain systems. It shows in examples how negligence in usage of a discharge pipe larger or equal to the pump’s discharge tap could lead to debris blocking the fittings. Locating the pump close to the pit wall may constrain the pump float to rise with the increasing water and result in the pump not collecting the water. Power failure may be avoided if an exclusive circuit for the sump pump or battery-powered backup systems are used.

    Chapter 21 of the same book explain what effects lightning can have on outdoor HVAC units and well pump motors and the type of forensic evaluation involved.

  2. Ishan Uppal
    November 15, 2016 at 8:55 am #

    As a structural engineer we are not aware of MEP systems that will be installed and their implications on our structure in the future.
    All of the presentations and talks that industry experts have given us indicate how the failure of any 1 system in a structure may cause the failure of the entire structure, if gone unchecked. Water and fire being the main culprits.
    This raises a question that whether the ACI and the AISC do have, or should have regulations/ codes for building design that takes into account such worse case scenarios where water or fire could result in structural failure.
    The ACI and AISC Codes may need to modified (if it isn’t already) for structures being constructed in the coastal cities, to account for increased probability of flooding and thus, the MEP systems being installed at higher elevations within the building to keep away from water damage.

  3. Shubham
    November 15, 2016 at 8:45 am #

    The root cause in the Submitomo Coil Failure case discussed was deterioration of material over period of time. In such cases, what should the owner do to prevent this?
    Should the building owner maintain record of ‘apparently vulnerable’ machinery and with the manufacturer’s manual, he/she should inspect them over a number of years to prevent the damage. This not only eliminates such concerns but also, eliminates insurance denial if required repairs are mentioned in the manufacturers manual. Is this an efficient way?

  4. Ommar E
    November 15, 2016 at 8:23 am #

    In forensics we deal with failures after they happened. We try to find what went wrong and put together as accurate as possible a scenario that incorporates what led to failure and failure mechanisms. However, from design point of view the aim is to understand, mitigate and prevent failures before they take place. And when it comes to building systems the earlier the better that’s starting from early stages of design and construction could pay dividends to owners and the designer reputation. A really good example for that I found in the words of the principal MEP for the world’s tallest building, Burj Khalifa in Dubai Mr. Luke Leung ’87, ’90g, of AE
    “My role in the project as the MEP principal oversees the design from conceptual to construction administration. Given its height and extreme environment, there are multiple challenges through-out the 4 years of construction document development from in-ception in 2003 to 2007. The main service elevator is the world‟s highest and rises at 504 meters (1,654 ft), more than the height of the Taipei 101 in Taiwan (448 meters) and almost one-and-a-half times as high as the Empire State Building in New York (381 meters). Racing at 9 meters per second it also has the world‟s longest travelling distance for an elevator. The chilled water sys-tem utilized up to 460 psi (32.34 kg/cm2) pressure to minimize transfer. The first super tall buildings that incorporated reverse stack effect monitoring and control system to measure pressure and temper reversed stack effect. The highest gravity feed fire protection system in the world utilizing the height of the building to provide required pressure for the fire protection system. Up to 800mm ( close to 3 feet) of creep and shrinkage has been account for in the build-ing to allow piping movement when the building starts shrinking at its own weight after construction. The Tower collects conden-sate water on chilled water coils from the atmosphere which is used to cool the domestic incoming water and irrigate landscaping around the tower. The Tower incorporates numerous enhance-ments to the fire and life safety systems, including “lifeboat” op-eration for elevators which allows for them to be used for evacua-tion under backup power during certain situations, which de-creases the total evacuation time by 45% over stairs alone.”
    The scale of things for this gigantic structure helps magnify and our understanding for the challenges and the enormity of the tasks to make the building systems work efficiently and in harmony with each other. An undertaking better faced head on rather than trying to figure out what went wrong later.

  5. Brendan B
    November 15, 2016 at 12:28 am #

    Reading the “Pex Plumbing Failures” helped explain in more detail how failures in other parts of the building system can negatively affect the building. The article talks about how a synthetic material Poltethylene (PEX) is starting to become more commonly used since the price of copper continues to rise. PEX can also bend around corners and it’s easier and quicker to install than standard copper or polyvinyl chloride (PVC) piping. The problem, however, is that PEX plumbing has led to failures due to exposure to chlorine and sunlight. In addition, chemical byproducts are often left in the pipe from the synthetic material.

    PEX piping offers great benefits, but can be costly to the building and people’s health, which is obviously not good. The decision whether to use PEX plumbing comes down to the owners decision between risk and cost. We have discussed many times how an owners’s decision to cut costs (such as an owner hiring a cheaper/less skilled contractor) has come back to hurt the owner in the long run (i.e. a collapse or increased maintenance cost due to improper construction). It also seems that synthetic materials are growing in popularity in the building industry. Similarly, fiber reinforced concrete uses synthetic fibers to increase the strength of the concrete, albeit at a higher cost.

  6. Rebecca M
    November 14, 2016 at 8:55 pm #

    Because some of the main types of failures include damage from water, whether it be from rainstorm flooding, moisture infiltration, corrosion, or natural disasters, I researched some solutions for MEP systems to deal with the problem.
    A proposed solution to mitigate flood damage for residential construction is to relocate the system or to create an addition above ground to house them. If this solution cannot be achieved, it is recommended the systems are placed onto elevated platforms with proper anchorage. A short publication by FEMA is attached for further reference. MEP systems that can’t be raised past the base flood elevation could be housed within a room made of finish materials more resistant to flood damage. FEMA is a great source for reading more on natural disasters and how to plan for or recover from the aftermath.
    Also for the problem of mechanical pipes corroding and causing a leak in the system, Water Damage Services offers a solution called Nu Flow that is essentially an epoxy liner and cleaning system that restores piping and reduces the risk of corrosion.

    https://www.fema.gov/media-library-data/1381404775001-64f574fe957f4911bc73afaf229f32ca/SandyRA3RestoringMEP_508_FINAL2.pdf

    • Yemi O
      November 15, 2016 at 8:28 am #

      Insightful article. Interesting to know that FEM has plans in place for when disasters such as hurricane sandy occur.

  7. Joe H
    November 14, 2016 at 6:07 pm #

    The more I think about MEP forensics, the more I feel the need to find a correlation between that and structural failures. When we design the building, our goal is to design it as on whole cohesive building, not 5 different systems slapped together. Therefore it is important to look at failures the same way. As we’ve discussed in class multiple times, while there is usually only one actual failure, there are many reasons and factors for the failure.

    I think it’s pretty obvious that in the event of a large failure, there is always a risk for another failure after the building has changed. This could be extra load onto a lower floor, or direct damage to duct work or piping. But what about failures working together and acting at the same time? Just as integration in design is essential to making the highest quality buildings, an integrated failure could create complex problems but also lead to important understanding of building systems.

    I don’t know exactly what one of these failures would look like. Perhaps the heat exhausted by a cooling tower is enough to affect the properties of a material (probably not steel, but perhaps finishes of some sort). Today in the SGH presentation we saw an example of how moisture and pooling of water deteriorated columns. What if a building tried to collect water for reuse, but the collection area was not constructed properly or in the wrong place?

    At the end of the day I think that studying both integrated design and integrated failures can help both designers with better integration and investigators understand problems better.

  8. Alec B
    November 14, 2016 at 10:45 am #

    I saw that a few of you discussed the use of laser scanning and point clouds. I found a neat “interactive” PDF of a floor plan of a renovation project that looks like it was created using a point cloud. If you have the latest version of Flash, there are red boxes that appear on the PDF. After clicking on a red box in plan, it takes you to an interactive 3D view of the space where you can pan around, rotate around the space, and even zoom in to see as-built conditions.

    For context, the project was a renovation project at the VA in Asheville that included replacing a mechanical unit in the crawl space below the first floor.

    http://www.fegstructural.com/announcements/point-cloud-by-others

    • Joshua Z
      November 14, 2016 at 9:41 pm #

      Alec,

      I mentioned in my post that I worked with point clouds during my internship. You bring up an interesting point here, and this was something that I encountered while I was on the job as well. A lot of times, the laser scanning device will take pictures at each reference point after it is finished scanning and taking measurements. The pictures and the model were linked together by common points that appear in each shot. These points were small white spheres that were positioned throughout the building or area being surveyed so that the data can be connected and meshed together once all of the information is gathered. It’s a fascinating process and allows one to model and see the entire building without actually having plans or being there.

      • Shane M
        November 15, 2016 at 12:22 am #

        I am curious to know, are these scans commonly requested by owners of old structures or those in need of existing drawings? I am not very familiar with the process but it seems like it would be an expensive option for an owner.

        • ErikS
          November 16, 2016 at 10:31 am #

          Shane, from what my experience with the laser scanning it is primarily used during renovation, reconstruction, or addition projects in which the existing building or structure does not have drawings, or at least adequate drawings, to allow the project team to adequately determine proper connection details, structural upgrades, etc to proceed with the project. This allows the design team a very close approximation of the as-constructed building to ensure the repair design is as accurate as possible. We also used the laser scanning point cloud once on a very unique shaped object that we were investigating and required repairs. We used the point cloud data to develop a structural model to analyze to determine the forces applied to the structure. Without the point cloud data developing the complex model would have been extremely difficult and time consuming including the time required in the field documenting and measuring the structure.

  9. Di W
    November 14, 2016 at 2:54 am #

    Several different ways in forensic engineering were introduced in Mr. Boyer’s presentation. Those high-tech methods of investigation or modeling showed that the amount of information available to building owners and forensic engineers is increasing. Say laser scanners and similar hand-held measuring devices are enabling the collection of millions of points of data. The changes in how buildings are designed and how structural information is conveyed are changing how forensic engineers understand and explain their structures and their findings. Forensic information modelling assists in understanding the as-built information of a structure, which in turn is crucial to understanding how the structure has behaved and how it will behave in the future. I look forward to learning more modern technologies in this area.

  10. Shubham
    November 10, 2016 at 9:01 am #

    Very fantastic introduction by Mr. John Boyer especially for first time learners of MEP concept.
    As a part of risk assessment, which is done on the later stages while buying insurance, the owner should do it in the first place when the building is being designed. Facts like elevation, proximity to flood prone area are not going to change. With this the necessary changes can be incorporated, rather than changing the conditions on later changes. For example, in one of the case studies the ground floor generator was shifted to roof. Such heavy load shifting may need approval from the original designer. In fact, such recommendations should be given by FEMA/ Building Codes (I am not aware if they are already mentioned).

  11. Mehrzad
    November 10, 2016 at 8:06 am #

    The lecture was informative in showing multiple MEP failure case studies and how a detailed site investigation, interviews with employees, facility managers and contractors, and collection of a complete list of damages are necessary to prevent false claims by the owner or manufacturers. It showcased in Sumitomo coil and Scotiabank riser case studies that how inappropritate local detailing can have large failure consequences similar to structural progressive collapses.

    The National Academy of Forensic Engineers journals have more case studies that need to be purchased:

    http://www.nafe.org/assets/images/pdf/nafe-ee2-table-of-contents.pdf

    These two links also have some forensic case studies:

    http://www.efiglobal.com/Knowledge-Center/Case-Studies/

    https://www.case4n6.com/case-studies/?all=1

    PDF file below shows Leica scanners and a software packge that can capture very fine accuracy of the existing MEP and structural configurations:

    http://www.clearedge3d.com/wp-content/uploads/2013/10/Nederveld-Case-Study-Hospital-MEP.pdf

  12. Ishan Uppal
    November 10, 2016 at 1:16 am #

    Mr Boyer’s MEP Forensics presentation was very informative and provided insights into cases where fire was the main cause of damage/failure. After many presentations dealing with water damages to structures, Mr Boyer’s talk reminded us of the damage fire can cause.

    The case study of the GAP warehouse was the most perfect example of Murphy’s Law I have ever come across. What are the odds of a fire going out of control at a major storage facility as the fire fighting alarm systems were being tested! Mr Murphy would be so proud! Same with the case of fireworks setting pork fat alight at a meat processing plant in Wisconcin. These cases reestablish the fact that one must prepare for any and all eventualities, no matter how remote. And as forensic engineers undertaking risk assessment, these situations must be considered a possibility.

    The long term damage caused to railway train tracks and to many basements, including that of the WTC, after thunderstorm sandy, due to brackish water flooding them was an interesting case study. Such situations will keep happening with increased regularity in the coastal cities of the world as the sea water levels rise. The simple method of moving the MEP systems from the basements of building to higher levels in a structure can be an effective tool to face this problem. However the industry will soon have to come up with more solutions to this impending problem.

  13. Brendan B
    November 10, 2016 at 1:16 am #

    Although this is a building failures course, I have only really considered structural failures to be a building failure. In reality though, a mechanical or electrical failure is as much of a building failure as a structural failure is. Although MEP failures are not as noticeable as structural failures, they can still be costly if not taken care of properly. A failure to the AC unit/condenser water system, such as Case Study 4 in Mr. Boyer’s presentation, can result in water damage throughout the building. If this building holds expensive equipment (medical equipment, virtual reality equipment, etc) this failure could results in the loss of millions of dollars. This failure is not as gimmicky as a facade failure or roof collapse, however it still effects the inside of the building in a severe way. Mr. Boyer’s presentation on MEP Forensics opened a new door to forensics in the building industry. It was a pleasure learning about something I knew absolutely nothing about.

  14. Yingzhe You
    November 10, 2016 at 12:39 am #

    Mr. Boyer’s presentation was very informative for me. Several cases were presented during the lecture. What he said impressed me most was that we should to take mass photos during the investigation. When doing the rec hall modeling after the first visit to rec hall, I found that I might need some information to determine certain part of the structure. But when I looked at photos I took, I couldn’t find a proper one that could show the details I needed. But luckily, we had a second chance to visit rec hall. When doing the actual forensic work, structure condition may change before we can take an another trip to the site, so it’s really important to gather all information we need during the visit. That’s to say, we need enough photos to help us analyze.

  15. Ommar E
    November 9, 2016 at 11:04 pm #

    MEP Forensics lecture presented by Mr. John T. Boyer provided a unique opportunity to go back to the fundamentals thats looking at the building as a system of systems. Put together and working in harmony, these systems attests to the notion that there is some degree of built-in inter-dependency within the system. An understanding combined with idea that failure could come from a single, multiple or combination of factors or sources affecting the system/systems. As structural engineers our sole responsibility is to facilitate the structural system which gives the building its cohesion and stability. At the same time, it is the system on which all other systems are supported. Obviously, failures in the structural system is detrimental to other systems and vis versa to a variant degree. So, to draw from the presentation and how putting things together and building a model that take into account the different components involved is key to understanding how a failure in system came about. And again we were reminded that the devil is in the details. Overlooking very simple detail in an air-conditioning system could end up affecting other systems and eventually causing failure like the one shown in the case study.

  16. Shane M
    November 9, 2016 at 10:35 pm #

    I was very glad that we got a chance to hear about a different side of the failures and forensics field. I can see that it is important for all designers to be careful of their work and to really look into the criteria of the systems they chose. Also it appears to me that MEP failures are more frequent than structural because MEP systems can be easily tampered with. Such as the case we discussed earlier in the semester with the explosion of structure. If I remember correctly it was due to an owner removing the natural gas check valve after selling the building. MEP systems are machines with many intricate components, this only makes them more susceptible to failures. These failures can unfortunately lead to serious damage due to the fact that they are operating with water and/or electricity.

  17. Di W
    November 9, 2016 at 10:31 pm #

    It was a good chance to meet Mr. Boyer and listen to his speech. Mr. Boyer’s presentation involved many fields such as the scope of work of forensic engineering, the investigation tools includes FIM, 360 degree camera, maps FLIR etc. Camera is a basic tool in investigation because he said photos record everything. I am also pretty much interested in one of those investigation tools which is forensic information modeling (FIM). It is possible to create overlays and tag items by using Google maps, Bing, Leaflet or other modern mapping platforms. Here I found an article that specifies how FIM works in forensic engineering. I think someone may like it.
    https://s3.amazonaws.com/tt_assets/pdf/forensic_engineering1.pdf

  18. YusufA
    November 9, 2016 at 10:01 pm #

    It was a great presentation by Mr Boyer on MEP Forensics. Having a view into the MEP forensic engineering different from previous structural failure gives another dimension of learning. The various case studies also did give good insight into the topic and provided further understanding. It is fascinating that majority of their work is been done for Insurance companies to estimate repair costs.

    The idea of subrogation mentioned is interesting but I believe it is also an important one which could help in avoiding fair amount of future failures. At least the one that may involve a manufacturer defect. This is because a manufacture who has experienced such or who know about the possibility of being checked if one of its product is found defective will improve in quality and testing before making any product available for construction use.

    The incorporation of the FIM software is also a very innovative and important one which I believe would help make forensic work easier and quicker just as the BIM software is doing in construction. This would reduce the time in which a report is being produced as well as the quality in detailing.

    Of the 9 case studies which was mentioned however, I found the World trade center and the Transportation authority interesting as this once again has to do with water failure. Majority of the MEP damages however could be summarized as caused by water and or fire.

    • MichaelB
      November 14, 2016 at 8:35 pm #

      Yusuf,

      You bring up a good point about subrogation cases pushing manufacturers to correct flaws in their design. It reminds me of the the Z channels used in light gauge metal buildings that professor Parfitt. Although the Z channel was not a design flaw, many of the buildings using it had flaws in its construction where compression zones were not properly braced. I can see how none of the manufacturers would not at fault in a subrogation case because the shape is fine in theory but it still brings to light the importance of evaluating how we design and construct buildings.

      • ErikS
        November 14, 2016 at 10:12 pm #

        Yusuf, I agree that manufacturers can and do learn from mistakes from their products or installation issues or design errors as well as threats of subrogation. However, with the shear knowledge of the multitude of failures that could occur on a project from any number of causes on any number of the materials they produce, they will often look at the most pressing (profitable) material(s) they produce and modify/adjust them and retest them to get a more satisfying outcome with the knowledge that they may still have issues they just cannot foresee. Also, there is the simple fact of money and that larger manufacturers can settle, or at least cover, larger law suits easier with less concern for the monetary impact. Now, I am not implying that larger manufacturers will sweep issues under the rug, I am just stating that it is easier for them to address the more pressing issues with their products.

      • ErikS
        November 14, 2016 at 10:14 pm #

        Yusuf,
        I agree that manufacturers can and do learn from mistakes from their products or installation issues or design errors as well as threats of subrogation. However, with the shear knowledge of the multitude of failures that could occur on a project from any number of causes on any number of the materials they produce, they will often look at the most pressing (profitable) material(s) they produce and modify/adjust them and retest them to get a more satisfying outcome with the knowledge that they may still have issues they just cannot foresee. Also, there is the simple fact of money and that larger manufacturers can settle, or at least cover, larger law suits easier with less concern for the monetary impact. Now, I am not implying that larger manufacturers will sweep issues under the rug, I am just stating that it is easier for them to address the more pressing issues with their products.

  19. Joshua Z
    November 9, 2016 at 9:52 pm #

    It was a pleasure listening to Mr. Boyer’s presentation on MEP Forensics. It’s always interesting to learn more about the world of engineering outside of our structures bubble, as knowledge is power. One particular thing that intrigued me about his lecture was his discussion of the usefulness of laser scanning to create a point cloud. This tool is useful in all facets of determining existing conditions. It is important in the forensic world as it allows a firm to see the layout of a room or building without actually being there. Essentially, the building or room can be moved into the office or wherever the analysis needs to be done, so that work can be done on it.

    I have experience working with laser scanning and point cloud mapping because of my internship this past summer. During my internship, I went on site to laser scan a series of buildings. When we returned to the office, we were able to assemble the point cloud and then import it into Revit. There, we were able to build a complete and roughly accurate model of the complex without any floor plans or dimensions through the use of the point cloud. It is impressive technology and essential to progress in the engineering world in the future.

  20. Rebecca M
    November 9, 2016 at 7:29 pm #

    Having a guest speaker discuss topics not directly relating to structural engineering or structural forensics was very beneficial to understanding the entirety of a building failure situation. Along with not not having much knowledge of structural forensics, it didn’t occur to me that the MEP side of design also needed to take building failures and damage into account. What struck me the most from the discussion Tuesday were the parallels that MEP forensics had with what I’ve gathered about structural forensics; the ability to utilize technologies to aid in reconstruction or distinguishing the causes, the major part water plays in general failures of equipment, facades, and structural members, and the construction claims and insurance aspect of estimating failures.

    To draw a parallel between MEP and structural forensics as well as structural design with the types of technology used, I’ve recently spoken with designers that have used point clouds to assess the current conditions of a space in addition to the assessment provided by the clients’ consultant rather than for assessing damage in an unsafe situation. It seemed that using a point cloud taken of the space created images accurately enough to assist those designers in a redesign of a space in the event where they didn’t have existing drawings.

  21. MBologna
    November 9, 2016 at 5:20 pm #

    Mr. Boyer’s presentation covered a wide variety of case studies. I was very intrigued by the case study involving the distribution facility. I would be interested to know more about the cause of the fire. As I understand from what Mr. Moyer mentioned, smoke was spread through the facility due to some fire protection systems being deactivated and due to smoke being pushed out through air ducts.

    What are the chances that a fire starts during the same time testing is occurring on systems that could have prevented the smoke from traveling throughout the building. I am curious if the fire was a random occurrence or whether it could have been prevented by stopping all distribution operations while the testing was going on.

    • MichaelB
      November 9, 2016 at 5:22 pm #

      Replying to my comment because wrong username was used

  22. Namwook P
    November 9, 2016 at 4:31 pm #

    It was great time to understand that concept. MEP forensic was not familiar with me and also structural engineers. However, in order to design and inspect buildings, I think that architectural engineers should understand that concept.

    However, I was wondering that how much engineers are concerning against MEP failure while they design the building. In the case of seismic event, many structures might withstand against earthquake, but secondary accidents could be happened from MEP failure.

    • Yemi O
      November 10, 2016 at 12:57 am #

      Namwook,

      I agree and understand your point. However, I think those are accounted for as well as Engineers often prepare for “worst case scenarios”.

    • philr
      November 10, 2016 at 11:58 pm #

      If you are talking structural accidents, I believe there are provisions in ASCE-7 that specifically detail the seismic requirements for non-structural (MEP and other) components.

    • Prateek Srivastava
      November 11, 2016 at 9:40 am #

      I totally second your point regarding the attention structural engineers have to pay to MEP and other secondary components while designing a building against hazards. Though, there are separate codes for MEP regarding how to install these services safely and how to keep them intact in hazardous scenarios.

      There are provisions given in, IBC Chapter 16, as well as Chapters 11-13 and 15-23 of ASCE 7—Minimum Design Loads for Buildings and Other Structures, addressing seismic design, where, we can look for guidelines and these also show how the structural building and non structural components should behave symbiotically.

      Buildings and other structures that support the mechanical, electrical, or plumbing (MEP) components are divided into occupancy categories which are used to determine the level of seismic/wind loads and detailing required.

      Essential facilities such as hospitals, police and fire stations, power plants etc are examples of higher level occupancy categories (III or IV), which can require a higher level of analysis, design, and detailing than a lower occupancy category building in the same region of the country. Essential facilities like these require immediate occupancy or continued use after an earthquake/hurricane, which can require continued function of MEP components after an earthquake/hurricane as well.

      If we talk about earthquakes, so to determine the level of analysis, design, and detailing that will be required for the structural and MEP components, the structural engineer will need to calculate the seismic design category and proceed further as it will let the engineer know how severe the earthquake is going to be like a building designed in California requires more conservative design than a building in New York. Thus, it is important to consider every aspect.

  23. Alec B
    November 9, 2016 at 10:38 am #

    I found Mr. Boyer’s talk yesterday incredibly interesting and informative. I was really blown away with some of the technology that is out there these days that significantly help the field of forensic engineering (such as TT’s Forensic Information Models, laser scanning, and thermal imaging). Mr. Boyer mentioned how oftentimes TT utilizes their designers during investigations as a form of “peer review.” From what I gathered, TT’s own designers are put in charge of “re-designing” a system to see how they would design the system if given the design task. This way, any differences in design may become apparent which then leads to questions such as “Why are there differences?” and “Do the differences matter?” It seems like an excellent manner to expose potential problem areas within an original design surrounding a building failure.

    With the recent emergence of virtual reality, do you see this type of technology making its way into the forensic engineering industry? Perhaps laser scanning is the closest (and most practical) thing involved in the industry right now compared to virtual reality, but it’s interesting to think of how the development of different technology can significantly reshape the industry as we know it.

    • Joe H
      November 9, 2016 at 9:47 pm #

      Alec, you bring up a very interesting point with virtual reality. After reading your thoughtsI immediately started thinking as well of how it could be utilized. The first thought that came to me would be recreation of the space before the failure. If an engineer is able to put him or herself in space that failed before it failed, perhaps they could see things that they wouldn’t be able to normally. this would be much more practical for larger failures than small failures of course.

      I think more beneficial than VR would be computer programs that allow you to more accurately recreate the building conditions and allow you to test certain hypotheses on the failure. Thinking back to the discussions we had on flashing and terra cotta assemblies, it would be incredibly useful to be able to model both correct and incorrect assemblies as part of the investigation at a very high level of detail (perhaps this does exist and I’m just not aware of it).

  24. Prateek Srivastava
    November 8, 2016 at 9:31 pm #

    It was a pleasure meeting with Mr. John T. Boyer today. His presentation touched upon many topics related to Forensic Engineering, starting from the basic understanding as to what is Forensic Engineering and what does a forensic engineer do like property condition assessments, property investigations, litigation supports etc.

    The thing which caught my attention was FIM (Forensic Information Modeling), which is basically on the lines of BIM providing a nexus to share information thus making it more interactive and accessible for the people involved. Other investigation tools which Thornton Tomasetti (TT) uses are damage matrices, thermal imaging, maps, laser mapping, cameras and many more.

    He also walked us through seven of his case studies which involved primarily MEP components whether in terms of HVAC failures, generator failures etc. caused because of fire, floods/hurricanes.

    The failures have been severe but the usage of spreadsheets/damage matrices, FIM made the case studies look very neat in terms of collection of information required for the remedial measures.

    One take away point for me is to actually look how important is to keep all the information organised which one may use for future reference as well. The documentation process is an important aspect of any project.

    There were some serious issues discussed in cases like Scotiabank Riser investigation where there was leakage of water from the piping system or the WTC and other facilities where the basements were drenched with brackish flood waters leading to corrosion of MEP units which are generally made of materials metallic in nature.

    On winding down, the presentation was an interactive one which told me about the various MEP failures which was a different angle to know about as me being a Structural Engineer.

  25. Yamile R
    November 8, 2016 at 6:43 pm #

    Today’s talk demonstrates the interaction of all aspects of a building when it fails. We learned about building failures in mechanical systems. That point of view being new to us, since we mainly focus in structural and envelope failures. We learned from a myriad of cases where the MEP team had to asses and valuate failures.

    One more evidence of how a failure at one point can affect a whole system is the Scotiabank riser. Building failure is like a cancer, when not treated or diagnosed in time, it has a great risk of spreading all over. In this high building, the HVAC pipe had two points of damage, but at some time after, several locations also had leaking and damage as consequence.

    • ErikS
      November 9, 2016 at 9:14 pm #

      I would also like to thank Mr. Boyer for presenting to the class about MEP forensic investigations. Yes, again we see how buildings act as a whole and not just individual parts and a single mistake or issue in one area can create unintended consequences elsewhere. A water leak through a window or improperly detail below-grade waterproofing, or more severely a flood, can lead to an electrical short. The short can cut power to the building; however, due to constraints on the existing building’s budget the generators located in the basement are unable to initiate due the water in the basement. As time passes the short starts a fire and the fire-suppression system, powered by the primary and/or backup power, is unable to douse the fire. This is extreme but this can and does happen. The forensic engineers must follow the clues to determine the source, or sources, of the ultimate failure.
      Another issue buildings encounter, especially newer, “tighter” buildings, is unintended consequences due to improperly designed, or at least improperly functioning, mechanical systems. These issues demonstrate the interdependencies of the structure, building enclosure, and mechanical systems. Joe Lstiburek is a great source of information, and often times humor, regarding forensic investigations of how buildings perform. He often discusses how when buildings suck or blow at the wrong times they can create issues within the wall assembly that can lead to moisture build-up, mold, corrosion, or other deficiencies. Here are three of his articles: https://buildingscience.com/documents/insights/bsi069-unintended-consequences-suck; https://buildingscience.com/documents/insights/bsi-070-first-deal-with-the-manure; https://buildingscience.com/documents/building-science-insights/bsi-012-balancing-act-exhaust-only-ventilation-does-not-work. Search his site for additional information on topics you may not have even known existed.

  26. mkev
    November 8, 2016 at 2:24 pm #

    You may recall that Mr. Boyer talked about the problem of having equipment and emergency generators in the basements during storm, high water and flood events. Check out this article “Why Do Hospital Generators Keep Failing”. https://www.propublica.org/article/why-do-hospitals-generators-keep-failing It really is a life or death matter.

    • Yamile R
      November 8, 2016 at 6:43 pm #

      This is a very interesting article. As Architectural Engineers we have always learned to design hospitals as part of the priority building category in importance. And yet they have flaws in their mechanical systems, due to locating the generators at the basement and to the lack of correct testing.

      The idea that makes me wonder the most is that new codes or addition to codes does not apply to older buildings. According to the article: “Newly constructed hospitals are supposed to place their generators and fuel in adjacent locations above flood level. But the location requirements do not apply to already-built hospitals.”
      So how can we prevent older buildings from failing, on up-to-date discoveries of failure, if they are not required to keep up with new codes?

    • Prateek Srivastava
      November 8, 2016 at 8:07 pm #

      Nice article providing information about the failure of mechanical systems. The article discusses about failure cases, where several times in the past during floods and hurricanes, the hospitals had to deal with such life threatening scenarios where the power backups for hospitals did not fulfill their utility.

      Well, as discussed in the article, i did not the get the point as to why even after learning from so many hazardous incidents still medical care centers have their critical backup systems like generators in the basement, why?

      Well, on putting my two cents in, retrofitting older hospitals to add a generator on the roof costs millions of dollars.

      Secondly, it’s not certain whether roof generators can withstand hurricane-force winds, and if the device that pumps fuel to the generator is located in the basement, the generator will be useless in times of urgency.

      The size and weight of the generator can also be an issue, whether the roof could withstand such high loads during hazardous conditions, otherwise it may lead to overall building collapse.

      But considering the gravity of situation involving high risks of life, some measures are to be taken to resolve this problem before any other calamity.

      • YusufA
        November 15, 2016 at 6:57 am #

        Prateek,

        On a similar note to your point.

        I personally do not have major experience in coming across MEP Failures. Going over the Hospital failure article and reading over several of the comments in the page, it seems to me like the problem is far from being solved if measures are not put in place ahead. These generators are present only for emergency situations and the only solution I find to avoiding creating a double emergency during the emergency period is by not testing the systems.

        It was written in the post that these generators are expected to be tested 12 times a year for 30mins and once every 4 years for four hours. I think this is an adequate measure which if put in place properly would avoid the body counts in emergency situations. Hence the need or the supervision, record and inspection of this.

        The issue of flood as a disaster could also be avoided with knowledge of an areas flood level prior to construction. For existing buildings, different other measures could be put in place including changing the generator position.

        The bottom line is that an emergency situation could be manually created few time just to test and ensure that when a natural unexpected one comes, the hospital will be ready.

        • Prateek Srivastava
          November 28, 2016 at 10:22 am #

          YusufA,

          I agree with your inference that we need to do trial runs to be prepared for the actual calamity. These practices give an actual panic condition and make people think about the ways to deal with them.

    • Yemi O
      November 10, 2016 at 1:04 am #

      Very Interesting read. I also came across this issue during my thesis project. I initially wanted to have mechanical equipment in the basement but there was the big issue of flood, and also some code related issues.

      In a lot of cases, as I have come to learn, mechanical equipment are better placed in the basement levels and because of that, protective and preventive measures are taken.

      However, all disasters and mishaps can not be planned for.

    • Yingzhe You
      November 14, 2016 at 11:31 pm #

      The reading material is great! I didn’t realize we had so many serious failure happened in the hospital. Since the backup generators are usually in the basement, and the basement is really vulnerable during the hurricane weather, should we put more effort in the basement design so that water intrusion can be controlled in a certain level to make the generator run well, especially in hospital design. Or can also, certain check should be made regularly to make sure all the generators in good status.

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