Climate change is happening with an accelerating rate. This leads to, among other consequences, record-breaking extreme weather or climate events around the world. Australia, well-known for its typical dry climate and prolonged drought across the entire continent, is now suffering historic rains, leading to severe, frequent, and deadly floods of centuries spreading through most of its low areas.

To make the matters worse, the rise of sea level, with an increasing rate recorded over the past decades, if continues, can generate large-scale, permanent flooding and a mass displacement of millions. Bangkok, Ho Chi Minh City and Jakarta, to name a few, are among the most crowded yet vulnerable places, which, according to a recent study [1], may be partly or fully under water by 2050.

Slowing or reversing climate change by reducing atmospheric carbon emissions is one side of the story. Having a survival strategy to improve human adaptability to destructive climate impacts is equally important and is more urgent than ever.

A typical adaptation strategy of living in a flood-prone area is raising an entire house above historical highest flood level, and/or using waterproof, flood-resilient materials for walls and floors. Despite their certain effectiveness, neither of these approaches assures a confident survival rate for the house when a record-breaking flood hits.

Reference(s):

[1] S. A. Kulp and B. H. Strauss, “New elevation data triple estimates of global vulnerability to sea-level rise and coastal flooding,” Nat Commun, vol. 10, no. 1, Dec. 2019, doi: 10.1038/s41467-019-12808-z.

The flood adapted house introduced by D.Invent is optimum for future builds to survive damaging floods. It contains key features listed below:

• The skeleton of the house is modified to separate the accommodating portion of the house on top from footings or supporting frames underneath, and make it float-ready.
• All parts of the house are further optimized to improve strength, durability, stability, and flood resilience.
• A patented supporting structure is introduced, including:
  • A buoyancy generator to provide sufficient buoyancy, or upthrust force, to float the desired portion of the house when water rises to its level
  • A stabilizer to help the house self-stabilize against drifting or high-speed flow while floating, and
  • A fine tuner to allow fine-tuning of local buoyancy to ensure balance while floating (without capsizing or flipping).
• A patented navigator combined with lateral shock absorber is introduced to safely guide the floating portion of the house up and down. It also ensures that the floating part of the house gets back to its original position when water recedes.
• A patented shock absorption mechanism is introduced to each floor of the house. It is designed to further harmonize shocks, vibrations, and provide protection to internal unrestrained facilities against both horizontal and vertical impacts while floating.

All these key features combined help protect the house, human occupants, furniture, and equipment inside against severe damages or injuries.

D.Invent's flood adapted house may be built from scratch or by renovating an existing one. All additional features are highly adaptable to houses of diverse shapes, layouts, and materials. It is especially suitable for typical houses in flood-prone areas, where the floor(s) have already been raised to a certain level above natural ground.

Like to collaborate, trial, participate in our pilot builds, design your own flood adapted houses, or receive news from D.Invent for future updates on this project? Click on the Interest Expression button above.

Want to learn more about D.Invent's flood adapted house? Click on the Learn More button below.
Want to see a sample house prototype and watch how it performs in flood? Click on the Demonstration button below.

Urban flooding happens due to numerous factors, a few of which are listed below:

• A rapid growth of population, leading to overuses or over-exploitations of available lands, including natural reserves, for residential purposes.
• That results in a fast reduction of available grounds for catching and storing rainfalls naturally. To make the matters worse, transport system and residential paving with the tendency of using impermeable paving materials apparently negate this very natural drainage mechanisms.
• The situation leads to an over-dependency on and an overload of existing drainage system. At high tides or after heavy rains, urban road systems tend to be more regularly flooded and the time required to dry out becomes longer. Flash flooding can easily turn to permanent flooding.
• Equally importantly, it is climate change and the consequential rise of sea level, not to mention more prolonged, excessive rainfalls in flood-prone areas.

All the factors above combined has made urban flooding a critical issue, which not only affects every aspect of modern life but, broadly speaking, also exerts negative consequences on the entire ecosystem.

Calcutta (India), Dhaka (Bangladesh), Ho Chi Minh (Vietnam), Guangzhou (China), Bangkok (Thailand), Miami (USA), Jakarta (Indonesia), to name a few, are among the most vulnerable cities worldwide to urban flooding, today and in the near future [1].

Constructing an additional underground drainage system is costly and not always possible, not to mention the challenges of its future maintenance/repair. Having an alternative drainage system, more effective, easier to maintenance or replace, and more sustainable, is virtually among the most important tasks in future urban development.

Reference(s):

[1] R. J. Nicholls et al., "Ranking of the World's Cities Most Exposed to Coastal Flooding Today and in the Future, Executive Summary", 2007. [Online]. Available: www.oecd.org

A patented drainage-able concrete road pavement introduced by D.Invent is an optimum solution for future urban roads to overcome, partly or fully, flooding risks. It contains key features listed below:

• Concrete material is strategically redistributed to create an additional water storage channel under and close to traffic surface. Once successfully constructed, the channel multiplies drainage capacity of the road (i.e., providing an additional drainage capacity at least twice the existing capacity of main water drainpipes).
• Cross section of the road pavement is redesigned with more reasonable material distribution, resulting in less concrete consumption (10-20% less) while ensuring its sufficient strength under heavy moving traffic. From structural analysis, the improved pavement can easily carry a moving traffic of 30 tonnes.
• A permanent internal formwork made of waste plastic is introduced to facilitate concrete casting. It also serves as a direct water storage and protects surrounding concrete against water-related degradations. The amount of waste plastic consumption significantly contributes to sustainability goals in local areas.

The water channel utilizes free- and large area right under road surface; as a result, it eases up the critical need for a large site clearance to build new drainage systems. Moreover, the channel is close to (if not on) ground surface, making it easier to construct compared to deep excavation/ tunnelling. All these factors combined make the drainage-able concrete road pavement a better option, if not ideal, for future urban road networks.

The project is being privately developed. Its details are not available immediately for public view. Interested readers are advised to contact D.Invent for more information.

Like to collaborate, trial, participate in our pilot builds, or receive news from D.Invent for future updates on this project? Click on the Interest Expression button above.

Fibers are normally added into concrete mixture in a random (or, ideally, uniform) manner. In general, each tiny fiber serves as a micro reinforcing element. Combined as a whole, they help concrete structures improve not only ductility but also load-bearing capacity. Fibers are also known as a potential measure in controlling secondary defects such as:

• Early cracking due to restrained shrinkages
• Surface spalling under fire or freeze-thaw cycling, and
• Damages inside out due to alkali-silica reaction (ASR).

However, issues remain when it comes down to the efficiency and effectiveness of fiber addition, which in most cases raise economic concerns from owners. A few of which are mentioned below:

• Random or uniform distribution does not reflect the actual fiber demand in concrete. In fact, depending on dimensional attributes and practical purposes of a structural member, it is a common situation that some locations in the member require dense fibers while the remaining locations may need less or no fiber at all. A uniform distribution in this case not only means an inefficient, unsustainable use of material resources but also puts more pressure on available budget.
• Effects of fibers are strongly influenced by their density and alignment inside concrete. For conventional construction techniques, numerous site activities (e.g., transporting, pumping, placing, compacting, finishing etc.) can cause an inevitable, large-scale re-distribution and re-alignment of fibers. This is especially the case for specialty mixes such as highly workable or self-compacting concrete, where fibers normally “flow” at high speed into place. The situation, to a certain degree, implies a potentially inconsistent, if not uncontrollable, quality of the final concrete.
• There are tricky cases where traditional reinforcing bars or mesh are either impractical or ineffective, and only fibers supplemented in a highly controlled, guided manner can fulfil the structural demands while keeping the cost down. For instance:
  • In automatic concrete production such as 3D printing, where reinforcing bars are virtually impractical
  • Very thin slabs and walls (e.g., thickness less than 170 mm), where providing multiple layers of reinforcing bars/mesh is impractical
  • Sprayed concrete for tunnel linings or slope protections, where mesh reinforcement is not sufficiently strong, and
  • Confined locations of high stress concentration.

The situation demands a new, sustainable strategy of distributing fibers considering structural performance, quality consistency, cost saving, and the ease of construction. This includes:

• Ability to supply fibers where needed
• Maintain a desired density and 3-dimensional alignment throughout the construction process
• Allow a convenient, mass fabrication and installation.

A patented injection device introduced by D.Invent is ideal for fiber distribution to local, congested areas of high stress concentration. The device is used after concrete placement. Fiber density and alignment, once injected, are not affected by, nor will they obstruct, other standard construction practices.

Fibers are injected to where they are needed with the quantity needed at each location. Density and 3-dimensional alignment of fibers are ensured by monitoring and adjusting the rotation and vibration of the device. The fibers as a result become more effective and may replace, partly or fully, conventional reinforcement, which is normally impractical to reasonably arrange in these areas.

A patented fiber mesh introduced by D.Invent is optimum to reinforce thin concrete elements such as slabs, walls, and shells, where providing multiple layers of conventional bars or mesh is impractical. It is also ideal for reinforcing sprayed concrete.

In this application, fibers are firmly attached on a base mesh. Fiber density and 3-dimensional alignment on the base mesh are strictly controlled during the production, and are not affected by the standard construction practices. The fibers as a result become more effective, which may replace, partly or fully, conventional reinforcement. The fiber mesh is firmly restrained in place prior to casting concrete.

The project is being privately developed. Its details are not available immediately for public view. Interested readers are advised to contact D.Invent for more information.

Like to collaborate, trial, participate in our pilot builds, or receive news from D.Invent for future updates on this project? Click on the Interest Expression button above.