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Better Blocks is an Idea Lab focused on the design, evaluation, and
implementation of low-cost, highly-insulating, earthquake-resistant construction
techniques for seismically endangered communities, with the goal of improving the
methods of construction currently used by the most resource-constrained citizens.
The international response to the emergency created by the 2005 Kashmir Earthquake
illustrated the difficulty in providing immediate relief housing to the large number of
settlements located in the remote regions of India and Pakistan. The majority of those
who lost their homes represent the most resource constrained communities, where
available earthquake resistant construction is unaffordable.
Housing in these communities, as shown in the above image (Figure 1), is commonly constructed of
unreinforced earthen walls or stacked stone laid with mud or weak cement mortar. During
an earthquake, the collapse of a particular portion of the wall progresses in an
uninterrupted manner to other portions of the walls and buildings. Because of the large
weight of the wall construction as well as the heavy sod roofs commonly used, the risk of
injury duringan earthquake is high.Heating these houses in the winter is resource
intensive, due to the relatively poor ability of the exterior of the house to retain
heat. Further, fires are often not well vented, leading to a dangerous buildup of
combustion products. Lung and eye problems resulting from these pollutants have devastating
effects, particularly on women who spend many hours indoors close to stoves and their
nearby infants who are even more susceptible.(2)
By improving the thermal performance of new and existing housing, less of the inhabitant’s
budget must be spent on fuel, and their exposure to combustion products can be reduced.
The risk of injury in these dwellings is not due to a lack of knowledge concerning
earthquakes. People living in Kashmir have been subject to earthquakes with a degree of
regularity over the centuries and they have learned to live with them. Analysis following
the 2005 earthquake by the EERI showed that structures built with traditional earthquakeresistant
construction systems did not collapse in most cases.
The first system, sometimes referred to as taq, consists of load-bearing masonry piers
and infill walls, with wood “runners” at each floor level used to tie the walls together
with the floors. The second system, known as dhajji-dewari, consists of a timber-braced
frame with masonry infill.(3) The problem is that many people cannot afford to build
with these higher priced systems.
National governments and the international community typically react to the destruction
created in the wake of a disaster but do far less to prevent it before it occurs. Rather than
assess how large-scale relief settlements would be financed and conducted after a
disaster, the “Better Blocks” Idea Lab will explore what incentives would be required
for local manufacturers and builders to introduce earthquake resistant materials at all
levels of construction. Minimizing the number of at-risk structures by improving the
existing building stock (as well as new construction) will better serve those who live in
remote regions that are difficult to reach after a disaster and will likely cost a fraction of
the amount required in a “post-disaster” scenario where an equivalent number of
unreinforced structures must be rebuilt, and their inhabitants relocated.
Building on the work initiated from a collaboration between a team in Professor Ashok
Gadgil’s Design for Sustainable Communities (ERG 291) course and students in
Professor John Danner’s Entrepreneurship in the Developing World (MBA 295a) course,
the “Better Blocks” Idea Lab is interested in collaborating with NGOs and local experts
to continuing our research. Weekly meetings will include collaboration with the locallybased
non-profits Architecture for Humanity and Pakistan Straw Bale and Appropriate
Building (PAKSBAB) as well as representatives from local construction firms working
with pre-fab construction (Philip Swett, CH Build, Inc. and Craig Norlene from Premier
Building Systems). Additional support and advice on fabrication will be provided by
periodic meetings with Houdy Goudy at LBNL and Professor Khalid Mosalam (dept.
Civil Engineering). We will also continue our correspondence with Brian Doherty and
Joe Hagerman at the Federation of American Scientists (FAS) to connect our work with
the related research that the FAS is conducting with SIP panels for domestic disaster
relief.
The Better Blocks Idea Lab will work to improve existing materials and methods of
construction in highly active seismic zones according to the following metrics:
Affordability: The people that are at the greatest risk of injury in an earthquake
are at risk not because of a lack of knowledge or skill in earthquake resistant
construction, but because they cannot afford to build with the more expensive
earthquake resistant materials.
Sustainable Use of Available Resources: Timber, a traditional building material
used for roof framing and earthquake-resistant masonry wall construction as well
as a common fuel for cooking and heating is becoming increasingly scarce in this
region. Alternate construction systems will be explored that incorporate a range of
materials with the fitness of each material being assessed in terms of its local
availability and sustainability.
Feasibility of Construction and Future Modification: Introducing a new
material or means of construction to a region often results in the development of a
“technology graveyard.” Traditional construction methods persist because they
are easy to replicate and to adapt/modify. Improvements in existing construction
techniques must be shown to be simple, intuitive, and capable of future
modification as households increase in number and wealth, without compromising
the structure or thermal performance of the initial building.
Thermal Performance/Fuel Usage of Resulting Construction: Simple, low cost
improvements to the thermal performance of the “building envelope” (walls,
floor, roof, doors and windows), can be shown to greatly reduce the need for
heating fuel. Because common fuel sources for heating include dung, wood and
charcoal, reductions in heating fuel usage can result in better indoor air quality
and consequently reduce the occurrence of respiratory and eye problems for the
inhabitants. By improving the thermal performance of the building, less of the
inhabitant’s budget must be spent on fuel, a commodity which is becoming
increasingly expensive.
Micro-Scale Business Feasibility: Typically the international community and
national governments react to the destruction created in the wake of disasters and
do much less to prevent it. Rather than developing models to assess how largescale
relief settlements would be financed after a disaster, we will focus on
exploring what incentives would be required for local manufacturers and builders
to modify their current practices to introduce earthquake resistant materials at all
levels of construction. Minimizing the number of at-risk structures by improving
the existing building stock (and new construction) will better serve those who live
in remote regions that are difficult to reach after a disaster and will likely cost a
fraction of the amount required in a “post-disaster” scenario where an equivalent
number of unreinforced structures must be rebuilt, and their inhabitants relocated.
No Proprietary Technologies: Technological innovations such as adhesivebonded
structurally insulated panels (SIPS) and “hardi-board” (cementimpregnated
fiber-board) are tempting materials to explore, however their
feasibility as a part of a low-cost building system is unlikely due to the need to
import them from abroad, or reproduce them in a controlled factory environment.
Although these materials could be considered as an introduction to the
construction economy in the long term, to reach those relying on the lowest cost
available materials for construction, cost and distance must be minimized.
Seismic Stability: Seismic stability must be achieved without significantly
increasing the cost of the construction material. For this reason light-weight
“lattice” structures composed high-strength tensile materials are being explored
that could be embedded into existing means of construction. Seismic racking tests
will be conducted over the summer on several prototypes under the guidance of
Professor Mosalam.
The product of this research will be on two tracks. On the first track will be series of real
working prototype “blocks” (evaluated on the metrics listed above) capable of improving
the safety and quality of construction in either “pre-disaster” or “post-disaster” scenarios.
Along the second track, the “Better Blocks” Idea Lab will generate appropriate business
models for scaling and producing the “blocks” to a cost that is affordable in the most
resource-constrained communities. By working on improving the materials of
construction rather than designing and importing “relief housing,” the inhabitant’s
ownership over their home and existing patterns of domestic life can be maintained.
Prototypes  Figure 2: Prototype modification of a standard 8” x 8” x 16” concrete block. This
prototype has two concrete exterior “skins” and EPS insulation foam sandwiched inbetween.
The inner skin is connected to the exterior skin mechanically with steel wire
(eliminating the need for any kind of adhesive). Embedded in each concrete “skin” are
diagonal steel wires which, when the walls are assembled, aggregate to become an
earthquake reinforcing “lattice”. The individual blocks are also connected by means of
the lattice, eliminating the need for mortar. Based on maximum allowable weight for
transport and construction (80lbs), the maximum dimensions of the block could be (1 foot
x 3 feet).
Figure 3: Corner assembly diagram based on concrete-skin prototype. In this figure the
lattice is created with high tensile strength polypropylene strapping, a low-cost strapping
material common used in shipping.
Figure 4: Connection prototype for sandwich panel composed of concrete-impregnated
fiber-board and EPS foam insulation. Connections are made by nailing the exterior skins
to a wood spline that is inserted into recesses in the foam. Based on maximum allowable
weight for transport and construction (80lbs), the maximum dimensions of the block
could be (4 feet x 4 feet) or (2 feet x 8 feet).
Main Contacts: Kyle Konis and Patricia Decker
Sources 1. EERI, First Report on the Kashmir Earthquake of October 8, 2005
2. J.A. Lee et.al. Affordable Safe Housing Based on EPS Foam, 2003
3. Basu, Sanghamitra. Preservation of Heritage Structures and Earthquake Issues. Guidelines and Lessons
from the Past. 2005.
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