New writing for publicart.ie
Structure And Sculpture
byJim Mansfield

What artists need to be aware of when engaging an engineer; stresses and foundations; withstanding forces - wind, water; stability and equilibrium, strength and resistence; support from the ground; durability; the performance of material; Health and Safety; Budgeting; the relationship between the engineer and the artist.

Architecture, sculpture and engineering have a large entwined history. At times, people alternated between roles; Brunelleschi, Michelangelo and others were leading Renaissance figures at the forefront of all these disciplines. Division of skills and knowledge into separate areas came later.

Now, there is again a closeness between the disciplines. Many large and tall buildings are being chosen with structural forms so that, hopefully for their promoters, an iconic building will be provided; - the Guggenheim in Bilbao, the Gherkin in London and a list of others in every ambitious city in the world. All these have a huge engineering input. There are close links between sculpture and engineering. “The Angel of the North”, the proposed standing figure on the Liffey by Anthony Gormley, works by Christo and Jeanne Claude and many other large and small-scale pieces involve engineering skills from many areas, including structural, marine and environmental.

Structural Engineering in a definition set out by the Institution of Structural Engineers is “the art and science of designing and making with economy and elegance, buildings, bridges, frameworks and other similar structures so that they can safely resist the forces to which they may be subjected”.

Public Art, by its presence in a space open to the public and not controlled by invigilators or others, needs to be safe and capable of withstanding the forces applied to it whether from its own weight, the forces applied by wind or water, by people or indeed accidentally. An engineer can assess these loads and using the characteristics of the proposed materials determine the structural requirements of the piece. The basic requirements of structural engineering include stability and equilibrium, strength and resistance together with support from the ground. These also include assessing the flexibility or stiffness of the piece as well as the durability of the structure for its environment.

Public sculpture can be large in scale. The forces involved, self weight, live or imposed loads, wind loads and the other applied loads cause disproportionate increases in stresses as the size of the piece increases. An elephant is the size it is for structural reasons and could not have the shape of a mouse. The proportions vary with scale due to the increase in forces and their related stresses and the movements, which may occur. The forces apply within the body of the piece and at connections internally within the piece and between it and its supports, be they a building or the ground.

There is a vast range of materials. All of these have different characteristics of strength, stiffness, durability and so on. The material chosen must be suitable for the use and exposure and must be capable of being fabricated efficiently and economically and of being placed in position safely.

Besides sizing a piece and its connections, an engineer should be able to help with the Health and Safety requirements. These can apply both during fabrication and erection and also during the life of the sculpture. Even temporary structures must be safe and an engineer can help assess the limitations of use.

There have been well-known and expensive failures, e.g. “B of the bang” in Manchester, where spikes failed leading to a £2million claim and the temporary structure in the UK where the artist (Maurice Agis)has been charged with manslaughter. The responsibilities of the artist, the engineer and indeed the sponsoring authority must be clarified.

1    “What do artists need to be aware of when engaging an engineer on a public art    project?”

The brief for the project should specify that an engineering assessment of the piece is required. This will involve location, foundations, materials, scale and so on. The requirements will vary from piece to piece. There must be scope for an interaction between the artist and the engineer so that the piece complies with the requirements of both. Engineers are generally responders to the design by others, be they architects or clients, but like to understand the reasons so that an appropriate solution can be provided.


2    “What are the areas that artists/commissioners seek advice and services on?”

The most critical areas are the strength of the piece itself. Structures have very specific design parameters in regard to stresses, which can occur and the allowable deflection of the piece. This applies both to elements within the sculpture as well as the connection with the base. Foundations must be designed to have sufficient reserves of strength to prevent overturning and the connection between the piece and the base is important. The artist and engineer must consider the materials to be used related to the environment with respect to the anticipated life of the sculpture. Health and safety is of importance in all works. The engineer may have a role in this regard.


3    “Advice and insight to artists taking on public art commissions”

There is a huge difference in responsibility between placing a piece in an exhibition with invigilators and its erection in a public place where there is no control over its exposure to the elements and its treatment by the public. Sculptures can be played or climbed on, people can sit on them, people can use them as vantage points during parades so the sculptures need to be designed to resist all the expected forces but, in addition, the engineer must consider accidental forces. Making a piece for public spaces must ally the artistic aims with the demands of safety. Both the artist and the engineer must understand the other’s viewpoint and produce a piece meeting both sets of demands.


4    “Other issues”

For sculptures with a public dimension, commissioners and artists should both be aware of their responsibilities. Public Art sculptures will need an engineering input to ensure they are safe and compliant with building rules and Health and Safety requirements. These rules are subject to ongoing change. In some cases, the commissioning body can provide the engineering advice but I have found that these recently often require the artist to engage an engineer. At the commissioning stage, when there may be a competition to select the artist, it may be premature to engage an engineer, but once a piece has been selected, engineering advice should be sought and this may involve modifications to meet the engineering requirements. The engineer should be willing to certify the design and to prepare drawings to allow the civil work to be priced and built.

Health and Safety requirements must be met. There are statutory duties on clients, designers and contractors. There may need to be a requirement to engage a Project Supervisor (Design Process), (PS(DP)), and a Project Supervisor (Construction Stage), (PS(CS)). These roles should only be adopted by those qualified to do so. This needs to be discussed with the client who must be aware of their responsibilities.

Budgeting is difficult for sculptures. There are the fabrication costs, the civil works costs, the artist’s fees and expenses. Depending on the materials used and the brief agreed, the engineer may be able to assist in determining the cost of the civil works. The budgets need to be realistic and cater for all costs including fees.

Engineers charge fees in a number of ways but these will reflect the work involved. Previously, there were standard fees but these no longer apply due to competition rules and fees have to be negotiated for each project. For large projects, a percentage fee may be charged but it is usually possible for a fixed fee to be agreed but this will need a clear brief between artist and engineer. Complex projects are often most difficult as the time input by the engineer may lead to a larger fee than both the artist and client expect. However, for both of them, it is important that a sufficient fee be allowed to let the engineer design and specify the structural requirements. It may well be that commissioning bodies should request that engineering fees, as well as Health and Safety costs, are included when proposals are being submitted by artists. The budgets for the commission should reflect the fact that engineering fees may occur and that these may vary with the complexity of the piece, which is not necessarily related to the scale.

Many engineers have carried out design work with artists over the years. It is important that there is an understanding relationship between engineer and artist so that a suitable compromise can be achieved. Artists may require engineers to carry Professional Indemnity insurance in respect of design and, indeed, they themselves may need to carry Public Liability Insurance for their projects. Most engineering firms are members of the Association of Consulting Engineers of Ireland (ACEI) who would be able to give contacts for engineers throughout the country.

I have carried design work and provided advice in respect of a large number of Public Art pieces in Ireland. The services varied from case to case but I have found recently that the requirements of clients are becoming more onerous. It is an enjoyable role but the engineering fees, except for the exceptional sculpture, will generally be breakeven only and so the prestige, publicity and indeed gain of knowledge are also important.

Author's Biography

Jim Mansfield
Kavanagh Mansfield & Partners
76 Merrion Rd., Ballsbridge, Dublin 4
01 6606966,   
jmansfield@kmp.ie