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Here are six concrete ways India can build a better future (Step 1: Stop using concrete)
We spend too much attention and energy on the Union Budget. It focusses on doing more things. It’s about building more roads, more low income housing, allowing investment, changing tax structures and of course, about telling us how badly the government has been doing this. We pay too little attention to building things better, so that they last, and they cost less to maintain. So that they stay built, and free us up to focus on building other newer things in the future. We often don’t address the “better” piece in a budget and, in order to protect the incumbent, established and inefficient industries, actually disincentivize newer technology. Read More
Road trial for light and cheap answer
New Delhi, Nov. 8: The government is set to test a new strategy to build highways, using geofoam – or giant lightweight polystyrene blocks – in a bid to slash construction time and costs and increase the life span of roads by reducing the risk of rain-triggered damage. Officials said the Union ministry of road transport and highways had cleared a proposal to use Thermocol, a popular geofoam brand, as the filler for the base in place of soil, as practised in many western countries. “We want to experiment with this western model for highways that we’re told could bring down the construction cost by 30 per cent and drastically cut construction time,” road transport secretary Vijay Chhibber said. A senior official in the ministry’s highway construction division said several countries in Europe, the US and Japan had been using geofoam for road construction for the past
seven years. The defence ministry’s Border Roads Organisation, which constructs roads along strategic and border areas of the country, is known to have used geofoam along some stretches. Sources said the road ministry, headed by Nitin Gadkari, held a meeting with consultancy firms and asked them to submit a cost analysis on the use of geofoam against conventional filler material such as soil. Several road infrastructure experts from the US had attended the meeting. Geofoam is about a hundred times lighter than soil, which means it is easier to install. Another advantage is that it does not expand or contract with changing temperatures in extremes of summer or winter. “Unlike soil, geofoam doesn’t get washed away during floods or landslides,” Chhibber said. “It will also help us avoid the use of healthy soil as a filler for roads.” Industry experts have given a thumbs-up to the geofoam plan, saying new and innovative ideas to build and repair roads were overdue. “The new material (being proposed) is more durable, easy to transport and requires less manpower for construction as sheets just have to be lifted and placed,” said Vishwas Udgirkar, a senior infrastructure consultant with Deloitte in India. India has about 1 lakh kilometres of national highways that make up barely two per cent of the country’s 48-lakh-kilometre road network, but account for 40 per cent of the nation’s traffic. A plan to promote the use of alternative materials and design in highway construction has been a priority for the government. Earlier this year, the road transport ministry had constituted an expert committee to recommend new construction materials and strategies. “We are consulting a cross-section of agencies and experts to adopt material suitable to local needs,” the official in the highway division said. The ministry has also issued an order that project reports on every future plan should consider all possible alternative design combinations but they should be apt for Indian conditions and economical. There have been instances when contractors proposed alternative materia
Geofoam Plays Prominent Role in $115.9M SR 167 Project
On HOV/HOT lanes near Renton, drivers must cross numerous general-purpose lanes to get off one highway and onto another. But a new flyover structure due to open in coming months will make travel much simpler and safer. “We have the HOV lanes in the center for both highways and so prior to this job, it required [crossing lanes of] traffic. If they are coming northbound on SR 167 and want to get on I-405 to get out of the HOT lane on 167, they have to cross three lanes of traffic to get on northbound ramp,” said project manager Gil McNabb. “What this does with the new
flyover structure is allow drivers to continue in the HOV lane. It’s a great safety mobility improvement to eliminate that cross over. It’s the same in the southbound lanes. If people are heading south and continuing on 167, they would have to cross four lanes of traffic on 405. Then they have to move back over to the HOT lane. We refer to this job as a direct connector. For those HOT and HOV lanes, this connects them directly in both north and south directions.” WSDOT broke ground on the $116 million project two years ago with Guy F. Atkinson Construction LLC of Renton, submitting the “apparent best value proposal of $115.9 million to complete design and construction” of the project. Completion is scheduled for mid-2019 with the new connector opening to traffic as early as the end of 2018. Construction crews worked with a variety of cranes to set bridge girders over twelve spans. This is about the tenth project in which WSDOT utilized Geofoam. The state opted to use the product on the southbound ramp because soils in the area are poor.
“Geofoam is used in a variety of applications, usually used in applications where the existing soils are not of good quality,” McNabb said. “It is used particularly around Seattle where you have really old utilities in the ground that are still working and there are concerns, for instance, about a pipe break. On both sides of the roadway there are adjacent wetlands. Most of the area there is standing water out there on either side of the highway. Once you get below the roadbed the soils are not good for structural construction. They use geofoam in lieu of other methods.” Other methods can add time and thus, money to projects. “Construction-wise, there are a lot of ways to improve the soil or build foundations into the poor soil,” he said. “You can do surcharging where you pile a bunch of dirt on bad soil and you monitor it ’til all the settlement is out. Those other methods take months. If you want to surcharge it, that takes months. Or you can go in and do ground improvements, pinpiles [small concrete piles]. There are a variety of methods to make the foundation firmer.” Geofoam, however, has distinct advantages. It allows workers to build on the poor soil with only minimal preparation. In this case, they put in and graded a layer of crushed rock. It’s lightweight — 100 times lighter than the equivalent volume of dirt if compacted — with each 4 by 4 by12-ft. block weighing only 248 lbs. That means it can be trucked in, moved to the specific site by forklift and maneuvered into place by just two workers. Approximately 2,841 blocks or 20,205 cu. yds. of material were used to build the foundation. “They can move them around and place them pretty easily,” McNabb said. “They are stacked in there and an adhesive is used to bind them together like a big block puzzle, forming a big wedge shape underneath the roadway. You’ve got walls on either side, ramping up from zero to approximately 40 ft. and that big cavity between the two walls is where the geofoam is. That took quite a wall. It’s a big ramp. They spent a couple of months placing this geofoam, placing it and building it up.” Geofoam is a construction-grade Styrofoam which essentially disintegrates when it comes into contact with any kind of fuel. To protect it, the blocks are capped with concrete and a waterproof membrane. The roadway goes over that. “The Geofoam allows us to get the facility open to the public earlier,” McNabb said. “It’s a huge advantage for us as a public agency and also just for the ease of construction and saving of time.”