At each end of a bridges is a structure which supports the weight of the deck. These are known as abutments, and they are often the first part of the bridge to fail. Blockage of the main channel by debris can cause water to look for the path of least resistance around the sides of the bridges, thus placing the abutments at risk.
Traditional bridge construction requires the installation of piles for the foundations of abutments—a lengthy and expensive process that involves specialist materials, skills and equipment.
But there is another promising solution: Geosynthetic Reinforced Soil (GRS) abutments. These allow for rapid and resilient construction of bridge abutments using locally available materials, without specialized equipment. With GRS, bridges can be constructed in as little as five days (Von Handorf, 2013) and at a cost 30-50% lower than traditional approaches (Tonkin and Taylor, 2016) .
GRS abutments are based on ‘geogrids,’ a high density mesh made out of polyethylene (plastic). Layers of soil and geogrid are combined to create a solid foundation for the bridge deck. Construction can be completed with basic earthmoving and compaction equipment, and a range of local fill materials can be used with guidance from geotechnical specialists.
It might sound improbable to hear a CFO say this, but I consider one of my roles since joining the World Bank Group to be that of matchmaker. Let me explain.
As I have noted in other blogs over recent months, the world’s emerging market and developing economies—EMDEs for short—face an enormous gap in infrastructure investment. Certainly it is not the only big financing challenge that countries face as they work to reduce poverty and extend prosperity to more of their citizens. But infrastructure underpins many aspects of economic growth, getting people to jobs and schools, connecting goods to markets, reducing the isolation of the poorest areas in many countries. And by some estimates, the sector’s funding gap is as high as a trillion dollars.
How is “green growth” benefiting India? One important dimension of that effort has been the use of environmentally optimized road designs, which has resulted in quality infrastructure using local and marginal materials, providing both economic and environmental benefits. Where available, sand deposits accumulated from frequent floods, industrial by-products, and certain types of plastic, mining, and construction waste have been used to good effect. Designs that use such materials have been about 25% cheaper to build, on average, than those requiring commonly used rock aggregates. The environmental benefits of using the above materials, in terms of addressing the big disposal problem of such materials and reducing the consumption of scarce natural stone aggregates, are as significant as the cost savings.
A second “green growth” dimension has been focusing investments on the “core” network, i.e. the network India needs to develop in order to provide access to all villages. Relative to a total rural road network of about 3.3 million kilometers, the core network that falls under PMGSY stretches over only 1.1 million kilometers. Prioritizing construction and maintenance on those critical road links will bring down costs as well as the associated carbon footprint.
- sustainable mobility
- sustainable transport
- capacity building
- rural access
- rural roads
- roads and highways
- Disaster Resilience
- climate resilient development
- Sustainable Communities
- Agriculture and Rural Development
- Climate Change
- South Asia
- Resilient Transport
Photo Credit: Flickr user highwaysagency
Infrastructure often makes headlines – and the sentiment is not always positive. Major projects must navigate a minefield of potential problems. One that is frequently overlooked is how the local community will react to the physical and environmental disruption that comes with major construction projects.
Achieving consensus and winning the ‘hearts and minds’ of stakeholders and affected communities for the construction of major infrastructure schemes can be challenging, but it is essential to deliver a successful project that benefits everyone in the community.
Gary Sargent, an engagement director from CJ Associates, is involved in a two-year consultation program for a major highway scheme in the United Kingdom and helped the authority design an integrated stakeholder engagement, communications and consultation strategy.
Here is Sargent’s advice:
Emerging technologies are transforming global logistics. The evidence is everywhere: Logistics companies are exploring autonomous fleets and “lights-out” warehousing, and are looking to Big Data for transport management and predictive analytics. Crowdsourcing start-ups are using a high-tech/asset-light business model. And e-brokerage platforms are providing real-time information from pickup to delivery.
However, much less is known about the impact of the Sistema Integrado de Transporte (SITP), a more recent reform to modernize and integrate all of the city’s bus services, eliminate the old, sometimes unsafe traditional buses, and put an end to the guerra del centavo—a phenomenon whereby drivers aggressively compete for passengers at the expense of everyone’s safety. The reform introduced a number of sweeping changes:
- The multitude of small private operators were required to form companies and to formalize their drivers and maintenance personnel
- Services were contractualized via concession arrangements
- The overall number of buses on the roads was reduced
- Bus routes were reorganized
- Old buses were replaced with a more modern fleet
- Cash payment gave way to a smartcard system
- The city applied stricter quality control, regulation and enforcement.
Public-private partnership (PPP) practitioners are sometimes guilty of thinking that signing the deal is the end of the story. You can’t blame them, really. Making a PPP work is a long-term process with a lot of players involved, each with his or her own priorities. Detailed technical, economic, and environmental and social reviews must be conducted to make sure the project is feasible and bankable. Often, sector reforms are required. Stakeholders – including the public – must be kept fully informed. The competitive bid, critical to any PPP, must be fully transparent so nobody will doubt the legitimacy of the outcome. It’s a long, hard slog to the end, and I can’t blame PPP practitioners from wearily planting the flag, declaring victory, and moving on.
But the signing is not the end; it is the beginning. And you can’t really declare success until the PPP is delivering real results for people. Sometimes, a follow-up PPP adds a new phase to a project, and sometimes new players are brought in. In any case, it’s worth going back and examining the results of PPP projects to see what happened and extract valuable lessons.
In March, the international community of statisticians will gather in New York and Ottawa to discuss and agree on a global indicator framework for the 17 Sustainable Development Goals and the 169 targets of the “2030 Agenda for Sustainable Development”. The task at hand is ambitious. In 2015, heads of state from around the world committed to do nothing less than “transform our world”. Monitoring progress towards this ambition is essential, but technically and politically challenging: it will require endorsement from all UN Member States on how to measure progress. In March, it will be the second attempt at getting this endorsement.
Why is it important? “What gets measured, gets done”. Measuring progress is essential for transparency and accountability. It allows us to understand our accomplishments and failures along the way, and identify corrective measures and actions—in short, it allows us to get things done.
What is the issue? Politically, the SDG process has been country led. This means that countries—and not international agencies, as in the case of the Millennium Development Goals—have guided the whole SDG process, including leading discussions and the selection of goals, targets and indicators. Technically, the development of a robust and high-quality indicator framework is highly complex: the indicator should align closely with each target, have an agreed-upon methodology, and have global coverage. In reality, many indicators do not. For example, the indicator proposed to measure the 11.2 SDG target (“By 2030, provide access to safe, affordable, accessible and sustainable transport systems for all”) is the “proportion of population that has convenient access to public transport”. Data is not yet available for this indicator. Additional indicators may be needed to cover all aspects of the target.
Already , frequently surpassing destruction to housing and agriculture in value terms. For example, a fiscal disaster risk assessment in Sri Lanka highlighted that over 1/3 of all damages and losses over the past 15 years were to the transport network. Damage is sustained not only by road surfaces or structures, but also by bridges, culverts, and other drainage works, while losses occur when breaks in transport links lead to reduced economic activity.
Along with additional stress from swelling urban populations worldwide, rising sea levels, changes in temperatures and rain patterns, and increasing severity and frequency of floods and storm events are the key climate change factors that make conditions more volatile. Ultimately it is these scenarios and their potential outcomes that threaten the longevity and functionality of much existing transport infrastructure. Indeed, .
Compounding the challenge of addressing these conditions is the difficulty that exists in precisely forecasting the magnitude, and in some cases the direction, of changing climactic parameters for any particular location. Meanwhile, the risk of wasting scarce resources by ‘over designing’ is as real as the dangers of climate damage to under designed infrastructure.
To identify the optimal response of our client governments to this threat and to ensure that all transport infrastructure supported by the Bank is disaster and climate resilient, – a partnership of complementary expertise to identify practical cost-effective approaches to an evolving challenge. We have come together to better define where roads and other transport assets should be built, how they should be maintained, and how they can be repaired quickly after a disaster to enable swift recovery.