High Lines | Lissoni & Partners

Technical data:

2019 International design competition: Create a new urban pathway

Selected project: Finalist

project name: High Lines

project location: New York, US

architect: Lissoni Architettura

design team: Piero Lissoni and Joao Silva

collaborators: Fulvio Capsoni and Juan Torres

structural engineering consultant: Antonio Capsoni

Brief

The Metals in Construction magazine 2019 Design Challenge is a competition to generate ideas for making foot travel a more attractive, engaging component of living and working in a city. With urban environments overly reliant on automobiles, creating elevated, landscaped thoroughfares that encourage foot travel can reduce congestion and improve the overall experience of urban life. One testament to this is the popularity of the High Line’s transformation of an abandoned railroad spur into a pedestrian walkway, stimulating development in adjacent neighborhoods along the way. The High Line captivates New Yorkers in a way that few projects do. It also demonstrates the potential such projects have to revolutionize urban landscapes by serving not just as places for public recreation, but also, when properly designed, as preferred modes of travel for commuters to use on a daily basis.

It is for this reason that the publishers of Metals in Construction magazine selected a pedestrian bridge as the subject of the 2019 Design Challenge. The challenge is to conceive of a pedestrian bridge that connects the transportation hub of the newly adapted Moynihan Train Hall with the city’s largest development since Rockefeller Center, Hudson Yards, where studies project 100,000 workers will travel to offices there from the rail station each day.

Your challenge: Submit your vision for a pedestrian bridge that navigates efficiently between the two sites. The design must reward foot travel by providing a distinctive experience that transports the user into a different place, encouraging its use as the desired mode of daily travel.

About the site: Moynihan Train Hall takes up two entire New York City blocks on Manhattan’s West Side, stretching from Eighth to Ninth Avenues between 31st and 33rd streets. The eastern half of the building across from Madison Square Garden and the present Pennsylvania Station contains the transportation hub in question, while the western half contains unrelated commercial use.

Hudson Yards is a large urban development occupying 28-acres that is transforming the West Side of Manhattan with construction of 18,000,000 square feet of state-of-the art commercial and residential space, including a new center for artistic innovation called The Shed. Accessible from the city’s widely popular High Line, competition entries must show the Shed as the termination point for the pedestrian walkway at Hudson Yards.

Concept

The main idea of HIGH LINES is not to create just another elevated pedestrian walkway but rather to reinvent a completely new vision for this part of New York.

Using the morphology of the city and the evident contrast of scale between the existing buildings and the sidewalk, our walkway evolves like a living organism that constantly changes shape through a structure that adapts to the heights of the adjacent buildings, so creating a new architecture that emphasizes and redesigns the scale of the city.

Suspended from the surrounding buildings like a web from spider man, (another creation of this city) our new pedestrian bridge will stretch from Moynihan station to the Hudson Yards without hindering any of the activity below. The only elements that will touch the ground are the vertical access points enclosing elevators and stairways, which will be placed at strategic positions.

The structure is composed mainly of steel cables equipped with OLED technology, providing the necessary transparency during the hours of daylight to then transform at dusk into a massive living screen illuminating the entire block and creating a new urban environment.

The lightweight structure of the walkway will float six meters above the busy streets in a transparent web-like structure, imparting a feeling of great lightness to its daily users.

Using solely eco-friendly and recycled materials this project reduces Co2 emissions and lowers production costs.

All the energy used to power this walkway will be obtained by piezoelectric technology, transforming the kinetic energy of the footfall into clean electrical energy.

Structure

The structural approach of the project aims to limit invasive interventions on the surrounding rooftops which could impact the waterproofing or the structures of the existing elements.

The objective is to conceive of an autonomous structure that rests on the rooftops of the buildings, working

through a process of gravity and counterweighting.

The significant forces in the tensioned steel cables suspending the walkway are balanced by counterweights arranged on metal frame structures with supports placed behind the parapets and aligned at two-meter intervals in order to distribute the load along the entire façade at an average of two metric tons per linear meter.

The elements of vertical connection between the road and the walkway act as stabilizers to maintain the equilibrium of the structural framework.

Sustainability

Could energy be harvested from our day-to-day activities be used as a source of energy to help power our modern society? Indeed, interest in such methods has been growing in popularity lately, especially with regards to renewable sources of energy. 

In particular, piezoelectric energy harvesting, which converts energy from vibrations and mechanical deformations into electrical energy, is a promising technique to supply power needs in unattended electronic devices, wireless sensor nodes, micro-electronic devices, etc., since it has high energy conversion efficiency and a simple structure. The main advantages of piezoelectric energy are its low production costs and its relatively significant electromechanical coupling coefficient.

In this project we harvest all the energy needs using piezoelectric technology.

With a daily footfall forecast of 100,000 people, this means our suspended walkway will receive 30,000,000 commuters per year. The path is 650m long so each commuter will walk 1300m which translates into 1700 steps. Multiplied by 100,000 people means 170,000,000 steps per day. With one step we can produce 2w of energy, so this gives us 340,000,000 watts, or 340MW per day of electrical energy.

This innovative solution for flooring with high added value converts the kinetic energy of the footfall into clean electrical energy by means of the piezoelectric effect and is coupled with IoT technology. It is easy to install and integrates perfectly with any type of traditional flooring as it placed below the surface and directly onto the screed or the pre-existing floor, so becoming invisible to users. This property allows it to be used in urban areas without disfiguring the urban fabric. It is highly efficient as each step can produce up to 2w of power. 20 steps are enough to power a LED streetlamp and 10,000 steps can fully recharge the battery of a smartphone (average energy 11.5 Wh). The technology employs recycled materials that reduce CO2 emissions, lower production costs and respond to the energy needs of end-users, mainly public and private companies with areas of transit and aggregation (squares, airports, train/bus stations and offices).

Energy harvesting is a rapidly growing market that can be integrated with current renewable energy solutions such as solar or wind. It is estimated that it will be worth 974.4 million dollars (US) by 2022, having grown by 19.6% in the five years from 2016 to 2022 (source Energy Harvesting Market Report by "marketsandmarkets.com").

We believe that this solution can create eco-sustainable lifestyles and a new way of combating environmental problems. It is invisible, environmentally friendly and integrates perfectly into everyday life.