12 Publishers

Architecture, Art, Design, Photography, Music & Writing

Category: Urbanism

Architecture May 2019

A Bridge to Remembering

“The bridge gathers to itself in its own way earth and sky, divinities and mortals.”

Martin Heidegger Building, Dwelling Thinking

Introduction

Competition Entry Report for Commemorative Bridge at the Irish War Memorial Islandbridge, Dublin

Gathering

Making a bridge provides the opportunity to gather the world, unifying the heaven and earth, the past and future.  It gathers up the earth, the banks and the river into a single thing.  In this location the bridge must prepare the visitor for the journey across the river to the memorial gardens.  This design brings together ideas about pilgrimage, memory and order.

Arrival

According to (Camillo) Sitte, the urban space before the church should be narrow and long, an extension of the processional route.  Here to shelter and enfold the visitor the prepared space is surrounded by stone walls that carry the engraved words of the war poets; a testament to the loss of innocence.  Water flows along each side and echo off the curved entablature to further calm the pilgrim.


Sound & Poetry

The courtyard provides a tranquil and isolated space in the busy city for the visitor to slow down.  This transition is a necessary purification process that prepares the visitor for the journey to the memorial garden.  The screening walls are formed to deflect and contain the sound of flowing water.  The concrete elements can be precast allowing their placement with minimal disturbance on the existing ground.  Openings to the rear allow the sound of birds and the wind in the trees of the nature sanctuary to percolate into the space.

Anchoring & Threshold

The bridge element is anchored to each bank with an entrance portico, a threshold that signals the crossing.  These embankment elements resolve the unique topography on both sides of the river, allowing for full universal access.  A hydraulic lift and staircase are provided inside the buttress element.  This strategy provides for a flat arrival court at +5.0 M and a flat bridge deck at +7.1 M.  This approach allows for 2.1 M clearance beneath the arch over the river as well allowing the river path on the southern shore to be uninterrupted.  These weighty anchors provide the necessary restraint for the bridge (see structural description below).  The northern portico element is also marked by a bell tower.  It is proposed that a bronze bell be commissioned as the percentage art project.

The Divided Path

In the medieval world the visitors to the great cathedrals were directed (under the eyes of Christ) to enter by one door and once their pilgrimage was satisfied, exited by the other.  These double doors are divided by the pillar that supports a Vesica Piscis above.  The porticos provide a similar choice.  The vaulted gateways are illuminated from above.  The allusions to both the Medieval Cathedral and Lutyens’ war graves motifs are not accidental.  The vaulted gateways frame the space and provide a sense of scale while providing clues to distance.



Material Character

The materials are driven by topography.  Concrete provide the material of abutment and bridge, brick the middle ground, while stone completes the entablature, extending to the structure of the bell tower.  Concrete provides defence against the vagaries of rising and falling water, marking the plimsoll line of the structure.  Brick provides tactile warmth.  The hard wearing surfaces are paved in stone, slabs over the courtyard and the bridge deck. Stone cobbles mark the crossing from one realm to another and completes the structures by capping the porticos and faces the courtyard walls.

Structure

The proposed bridge spans 45 metres from two concrete platforms.  To minimise the impact of the bridge on the environs the design carves out a narrow zone of impact.  The first stage is the sinking of piles and caps upon which the abutments will be constructed. The walls of the stair cores create a rigid box to connect the bridge.  The abutment foundation is anchored to the pile caps and in turn provides the landing point for the bridge’s arched soffit and flat parapet.

Sequence

The bridge can be erected simultaneously from both embankments using cranes located on the abutment foundations.  These lift the bridge segments into place. The first three segments are connected by joining steel cable strands together and tensioning them. The last segments can be connected using post-tension strands on-site and then lifting in place, with the final “keystone” dropped into place locking the structure together.

The bridge design balances nearly all of the self-weight of the bridge.  The tendons are located near the bottom of the cross section at mid-span, near the top of the section where bridge meets abutment, and then somewhere near the centre of the cross section at the far end of abutment or end of bridge.  Post-tensioning the tendons will pre-compress the concrete in the region of the cross section where there is tension due to bending under applied load.  Additional pre-stressing to ensure compression throughout the depth of section in the unoccupied bridge is used so that tension stress is never greater than the pre-compression.  This provides good deflection performance and long term durability.  The bridge will be built using C50/60 concrete and 15mm 7-wire post-tension strands.  At the base of the bridge we need 10×22 strands on each side and at middle 8×22 strands in total.  Additional 2-wire crossing strands, perpendicular to the main strands, will be placed 1m c/c.

Environment – Construction

The construction of the bridge relies less on disturbing and more on placement.  Aside from the piles and caps there is little disturbance envisaged for any part of the construction.  No significant excavation is envisaged for any construction with new surfaces established above or at the existing grade levels.  The arrival court is formed using cut and fill to accommodate the new levels at or near the existing grade level of the roadway.  The southern portico is accessed by a simple path, land graded either side to minimise its physical impact.

Environment – Post Construction

The post construction environment is similar to that prior to the introduction of the bridge, the mature trees (with one or two exceptions) are maintained and a nature enclave is protected (encouraged even) to the eastern side of the arrival court.  The existing river line and footpath are maintained.   The extent of the impact remains a narrow strip with limited impact outside of this zone.   Access to the bridge is facilitated using stairs, ramps and elevators.  It can be isolated or secured by decorative gates if required.


Marking Time

Marked by the sound of a bell, the sound of water, the mark of words, the echoes of people and place, this project had the ambition to enfold space and time with sound, light and words to guide and effect a change in the visitor.

 

Credits copyright reserved by authors

Design & Concept NJBA A+U; Noel Brady

Design & Engineering Bakkala Consulting Engineers; Chris Bakala, Erik Altmäe

Cost Analysis KMCS; Nigel Spence, Anthony Devane

Advertisements

Architecture July 2018

Dolphin’s Barn Urban Space

106_Plan1000_sm

NJBA A+U plan of intervention 

On the cusp of the new millennium NJBA A+U were part of a new urban space initiative championed by Jim Barrett City Architect at Dublin City Council.  Several under-utilised and under-valued spaces across the city were identified as part of the strategy.  Taking advice, suggestions and direction from the city architects and transport departments the task was to find a suitable model for urban renewal.  Concerns regarding the use of these spaces were paramount.

NJBA A+U Model Study 

Where social activities were positive they should be enhanced and where those activities were anti-social, proposals had to alleviate or deter.  Supporting mechanisms such as active public frontage and housing were important components of any solution.  In addition, where suitable, existing traffic use, including parking, could be maintained if it supported activity.

106_Section250_sm

NJBA A+U – Section through main junction

In this proposal, shared spaces were a key strategy to ensure valuable public activity, especially in font of the church.  Commercial uses along the edge of the spaces are re-enlivened with robust hard landscaped space augmented with trees and public lighting.  Where viable, residential uses above shops support passive surveillance.  A new mixed use building on the edge of the main public space provides financial subvention for the public realm works.

106_Plan250_sm

NJBA A+U – Main space in front of church with mixed use supporting building

The existing condition also suffers from access problems.  The crossing is difficult due to its unique geometry, topographical variation and traffic levels.  Safety was a priority from a traffic management perspective.  This scheme proposed both shared spaces for the low density areas alongside public functions in front of the shops and the church. For the main crossings more direct connections were proposed and the usual pedestrian barriers removed to facilitate easier movement of pedestrians.  This would necessitate a pedestrian prioritised lighting sequence.

106_View_sm

NJBA A+U – Study of new urban space and supporting mixed use building

Regretfully this scheme was not progressed.  It remains only in sketch form a potential solution.

Architecture April 2017

Tread Softly

Wolfe Tone Park is situated in the middle of Dublin on the grounds of the Church of St. Mary’s alongside the old Jervis Street Hospital.  Though many pass by and over the space between the de-consecrated Church and an old industrial building few think about what lies beneath.    The abstracted diagonal paving with its sparse planting and scattered remnants of headstones was once and remains a graveyard.

NJBA A+U –  Wolfe Tone Square

An international design competition was held in 1998 to reconfigure the enclosed park of stone walls, iron railings, paths and grassed over graves.  Even then the original headstones had been aligned along the boundaries facing into the space inside.  The original stone walls and railings identified the sacred boundary and provided minimal environmental protection from the wind and traffic noise.

NJBA A+U – Monument to Wolfe Tone

The solutions that found favour with the jury converted the bounded space to an unbounded non space, leaking to the street and the surrounding spaces.  Originally the intention was to bring St. Mary’s into the composition but that remains isolated.

Critically however the issue of the dead remained silent in many of the submissions as the graveyard is purported to hold cholera victims with many laid close to the surface.  Instead of revealing the interred it was considered more sensible to leave them where thy lay and move the remaining stones to the shaded end of the new space, leaving some to be presented along the western flank to wear away underfoot.

Our approach to the Wolfe Tone Square Competition was diametrically opposed to the washing away of this memory.   Instead we sought to honour the dead, and the living.  With the additional request to honour Wolfe Tone we split the honorific aspects of our interpreted programme in two contrasting courts connected with spaces for the living visitor.

NJBA A+U – Memorial to the interred

The overall plan for the Square would also recognise the significant environmental problems that currently exist.  The prevailing winds from the South West and West transverse the nearby buildings before hitting the Jervis Street hospital Building and directed downwards make for an uncomfortable location at best.  Our proposal sought to enhance the previous barrier’s tendency to shelter the space by including a system of screening with Birch Trees in raised platforms to break up the laminar flow of the moving air as well as a mask to the traffic noise on either street.  Coupled with an integrated seating and water system the visitor would be enclosed ion a place of calm reflection necessary in today’s world.  The square would also be capable of being closed at certain times to ensure that the place was preserved as a place of respect rather than a place of entertainment, a temptation that is all too often taken up in urban design schemes.

NJBA A+U – Wolfe Tone Square

As the council authorities seek to address the limitations of the current arrangement there is a plan to convert it back to some sort of grassed surface.  As people, re-inhabit the space, as they sit on the grass, as they lounge on those rare days of summer and lie back on the grass they will not know of those that lie barely a few feet away beneath the ground.

Tread softly.

 

Architecture November 2016

Air Rights Development

Air Rights 1.0 – York Street

NJBA A+U has been carrying out research into Air Rights projects in Dublin to leverage the potential of under utilised sites in and about the city centre.  Air Rights I for York Street in 2007 was selected for exhibition as part of the AAI’s (Architecture Association of Ireland) 2008 annual awards.   At York Street the proposal examined the under utilised space over the public realm, a street.

NJBA A+U York St Air Rights I

NJBA A+U York St Air Rights I

By exploiting the geometry of the space it showed how the city can be meaningfully stitched back together to create necessary ad desirable urban accommodation.   Addressing the twin concerns of much needed urban housing and by reducing the carbon footprint of the city Air Rights I offers a view towards what is possible.

NJBA A+U York St Air Rights I

NJBA A+U York St Air Rights I

 

Air Rights 2.0 – Baggot Street (Silver Sliver)

While Air Rights I addressed the nature of the public realm, Air Rights II examined the possible intensification of the private realm.

NJBA A+U Baggot Street

NJBA A+U Baggot Street

Silver Sliver is a proposal for a tiny site between two office developments exploiting the under utiilised space left over.   This particular site consisted of an existing single storey concrete framed retail unit with a roof car park overhead.   The site is under utilised apart from the car park with two blind gables looking down on the space in between.  This sliver site can be easily adopted for use as a residential use.

A lack of housing in the city and low density development means that citizens are forced outward to suburbs and dormitory towns, fuelling increase in CO2 emissions and long commutes.  Crippled by inaction and an excess of vacant land and empty buildings there appears to be resistance to exploring other solutions.

NJBA A+U Silver Sliver Baggot Street

NJBA A+U Silver Sliver Baggot Street

A light timber framed CLT system of standardised panels with CLT floors is an ideal material and technology for occupying this space.  By using the flat deck of the concrete roof (suitably reinforced) will allow a bolt on timber solution.  Rising on the back of the concrete structure the new stacked system of full height CLT panels allows the creation of what Corbusier called “Vertical Sites”.  On these “sites” it is possible to provide for a pair of twin 2 bed apartment units.

Rising above the street line a stepped plan and section shows how narrow sites can be occupied with minimal loss of light and air.  With weights of at least ½ that of a comparable concrete superstructure the new design rises effortlessly above the squat 1 storey retail unit.  The Retail unit is to be converted to a foyer for the new facilities providing a café and other communal services.  Above this level is a social “garden” space for use by the residents.  At the roof level of the new structure two additional social spaces are provided for the residents.

 

NJBA A+U Silver Sliver

NJBA A+U Silver Sliver

 

The new structure provides for 25 generous 2-bedroom apartments with natural cross ventilation and an open deck access to the central lift and stair core, for necessary fire protection.  The external skin is to be unfinished aluminium panel rain screen over insulation becoming a beacon in the environment for a new vertical city.  The tall roof elements that cover the social spaces are also ideal for using PV panels to generate some of the energy necessary for the building’s operation.

The system of construction using large numbers of repetitive elements allows for an economical solution and a rapid build.

Air Rights 3.0 

NJBA A+U’s research continues with Air Rights 3.0 which will begin identifying additional sites for examination.

 

Details of contributors….

For details of NJBA A+U’s range of design and research interests see; http://www.12publishers.com/NJBA.htm

Parenthesis Research Limited’s; https://www.facebook.com/ParenthesisDesignResearch/

Architecture August 2015

In-dependency

582_Poolbeg_Opt1a

The towers at Poolbeg may no longer be in use and though the ESB has shelved plans for their demolition there remains a gap that requires resolution.  Other proposals, from the fanciful to the practical have been made to which we are adding the obvious.  As both a symbol of a new era in abundant energy from non traditional resources (those other than the burning of coal, gas, oil or nuclear fuels) the ESB could re-purpose the towers to wind power.

582_Poolbeg_Opt2a

While the elements require some strengthening (internal steel lattice) they could be the masts to two elegant windmills.  This would be a potent symbol for an energy independent future right at the gateway to Dublin and Ireland.  Moreover this would be a wonderful opportunity to provide a test bed for newer blade technologies.  Glinting in the sun and riding high on the winds they would be a welcome addition to the  windsurfers on Bull Island at the heart of the designated UNESCO Biosphere.

582_Poolbeg_Opt3a

NJBA A+U

previously posted on linkedin