The Berlin 'Neues Museum' - a microcosm of Prussian building technology against the background of beginning industrialization

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1 The Berlin 'Neues Museum' - a microcosm of Prussian building technology against the background of beginning industrialization W.Lorenz Chair of history of building technology, Brandenburg Technical University, D Cottbus, Germany wlorenz@tu-cottbus.de Abstract The 'Neues Museum', situated in the historic center of Berlin, was built between 1841 and Heavily damaged during world war II and increasingly ruined in the following decades, it is presently awaiting restoration, the plans for which have been drafted by the British architect David Chipperfleld. This paper goes into the role of this masterpiece of Prussian classicism as a high-tech structure in its time, characterized by a wide range of unusual and newly developed construction methods - various light weight brick vaultings as well as hollow pot vaultings, but, of primary importance, a multitude of often hidden cast iron and wrought iron structural elements. The building's design and history, as well as the building itself, express a new, forward-looking understanding of construction against the background of the industrial revolution, that includes all of its aspects - the process of building, the produce of building and the challenge in terms of architectural and artistic expression. Now, 150 years after the building's completion, the rebuilding and restoration post new technical challenges, because as many of the historical structures as possible have to be made to perform their functions again, with due consideration given to conservation requirements. 1 Introduction In 1841, just 17 years after the works for thefirstgreat Museum in Berlin, designed by the famous Prussian architect Karl Friedrich Schinkel, had begun in 1824,

2 390 Structural Studies, Repairs and Maintenance of Historical Buildings foundation works for another Royal Museum were started. To distinguish this museum from the older one, it was since to be called simply the,,neues Museum" - i.e,,new museum". The kind of fascination that this nameless building held for the vistors in the 19th century as well as that which the ruins still do today, is multi-faceted. Figure 1: J-,», A Neues Museum Berlin - view from the Nationalgalerie, photo 1993 You may read this building as a late piece de resistance of classicism of the 1840s, which, in spite of its immense dimensions, remains noble and moderate in its proportions. It may also be interpreted as a compendium of world's cultures, a materialized museum concept that understands the building itself as being part of the exhibition, wherein the character and the decoration of each room are to correspond with the different objects of art on exhibit. But you can also read the building simply as a structure - and suddenly you understand that there is another, deeper sense in the distinction between,,old" and,,new": Far more than 17 years appear to separate the two museum structures. While Schinkel had based his design of the Altes Museum" primarily on the traditional building canon of stone and wooden components, his scholar August Stiller and his engineers, less than two decades later, countered with the development of a,,high-tech" structural concept, characterized by a wide range of unusual and, for the time, innovative construction methods - various types of light weight bricks as well as a great variety of hollow pot vaultings, but, of most importance and hardly visible, a multitude of cast iron and wrought iron structural elements.

3 Structural Studies, Repairs and Maintenance of Historical Buildings 391 The,,Neues Museum" demonstrates a new, progressive understanding of the word ^construction" that includes all of the term's aspects, construction as the process of building construction as the produce of building construction as a challenge in terms of architectural and artistic expression. Built right in the middle of the first phase of industrialization in Prussia, dating from 1830 to 1870, the Neues Museum constitutes a unique microcosm of a new Prussian art of construction against the background of the industrial revolution. Heavily damaged during the second world war and increasingly ruined in the following decades, the remaining torso is presently awaiting restoration (Fig. 1). Now, 150 years after the buildings completion, we face a new technical challenge, because as many of the historical structures as possible have to be made to perform their functions again, with due consideration given to conservation requirements. First steps toward stabilisation and new underpinnings were already initiated in the late 1980s. Meanwhile, the building has been the object of extensive structural analysis, including mathematical simulation and computer modelling. Two other papers, written by Josef Seiler and Wulfgang Henze, will provide background detail of the actual measures. I will start with a survey of some of the aspects of the historical concept and its execution. 2 The process of building Let us look first at the stage of the building process. I will give only a short summary of some of its aspects which will serve to illustrate the novel ways implemented by the builders to organize on-site building procedures and the manufacture of structural elements for a building more colossal than any ever previously seen in Berlin. Thus, for the first time in Berlin, a special railway was installed to open up the building site and to transport the building materials as fast as possible from the mooring at the embankment of the river Spree to the site. In the centre of the future museum a 120 feet high wooden hoist was erected to carry the trucks, without unloading and reloading, to the upper floors of the upward growing structure, where they could be moved on on iron rails to any corner. Another interesting aspect was the comprehensive use of steam power. A steam engine of 5 hp, built by the famous iron founder and mechanical engineer August Borsig, served as the central energy supply source on the site. It had many jobs to fulfill. So it had to run the pumps for the lowering of water, run the mortar mixer and the wooden lift. First and primarily, however, it was used for the pile driver which set the 2,344 wooden foundation piles. Considering that we are talking about a city like Berlin, and particularly its historic centre in which other types of foundations often had to be ruled out, and if you realize on the other hand what extremly hard working conditions went along with the use of traditional manually operated hammers, you can easily see the importance of the introduction of steam power for pile driving.

4 392 Structural Studies, Repairs and Maintenance of Historical Buildings Figure 2: Northern wing, section with bowstring girders, published by the architect, 1862 Moreover, some significant changes in the building process must be emphasized, which evolve as a direct result of the extensive use of cast iron and wrought iron structural elements - changes, that were to become characteristic for the further development of the building process in the 19* century: Important manufacturing operations were shifted from the site to the factory. The site itself was reduced to a mere assembly place for the prefabricated elements. It is interesting to observe that the architect August Stiller and his engineers had obviously still not realized all the new options which prefabrication opened up as well as the consequences inherent for the final planning until they had worked out the first details. When climbing up from the ground floor to the second floor in the edifice and taking a look at the different iron structures, you can really read how they learned, step by step, to reduce the range of different cast iron elements and to think in categories of standardization. The advantages are obvious: The standardization of the girders allowed for their casting in only a small number of different molds, the junctions and the connecting bolts were the same and so on. The standardization of structural elements - as contemporarily manifested, for example, in the already highly developed serial production of railway engines in Borsigs factory some hundred metres far from the Museum Island - took into account the new manufacturing conditions of the beginning industrial age. A quite impressive acceleration in building progress was the direct result of this innovation package. Schinkel, after having finished the foundations, had needed nearly two years to finish the rough construction work of his "old" museum. At Stiilers,,new" museum, the same works took less than one year.

5 Structural Studies, Repairs and Maintenance of Historical Buildings 393 ' 'f w Figure 3: Figure 4: Room of Majolicas, details of iron structure and zinc decoration, published by the architect, 1862 Room of Majolicas, details of iron structure, working drawing, watercolours, approx. 1843

6 394 Structural Studies, Repairs and Maintenance of Historical Buildings As on the level of execution, changes on the level of design, and on the level of engineering task are also worthy of mention here. These changes in the engineer's approach were to become characteristic for the further development of engineering itself. One thus finds the careful inclusion of theoretically founded dimensioning as afirststep towards statical calculation. One also finds draftmanship precision previously unheard of - a new, independent culture of constructional draftmanship apart from architectural draftmanship. The bare structure moved into the centre of interest, and the constructional draftmanship matured to become the engineer's very own way of describing his technical designs (Fig. 4). Last but not least, we must pay due attention to one quite interesting building process detail, a ritual that had previously been unusual not only in Berlin and in Prussia: Each of the wrought iron tie rods, which are decisive for the load bearing capacity of the bowstring girders and which are used throughout the northern wing, was tested in a hydraulic press before leaving Borsigs factory. One discovers a well organized system of quality control, a method whosefirstsystematic realization historians have normally attributed to the London Crystal Palace - although the Palace was built a full seven years after the Neues Museum. Thus, without even having taken a look at the structure itself it becomes obvious that the methods used to design and execute the Neues Museum alone provide a unique evidence of the 19* century changes in design and construction in building technology. Figure 5: Room of Majolicas, iron structure, actual state, photo taken 1993 (horizontal beams only for actual stabilization) Figure 6: Gothic Room, details of iron structure and wire stucco ceiling, published in a building construction textbook, 1854

7 Structural Studies, Repairs and Maintenance of Historical Buildings The produce of building Like the building process, the building itself - result of all those new methods - had little to do with a traditional structure, in defiance of outward appearances. Unfortunately, a considerable number of the many unusual and newly developed constructions no longer exist due to the devastations which occured during the course of and after the 2 * world war. We must thus mourn the lack of the wonderful light structure of the "Gothic" vault in the former Gothic Room, also called Room of Stars. Wrought iron ribs, screwed together with simple angle pieces, supported a wire stucco ceiling (Fig. 6), which was used in Berlin for the first time and which was one of the first examples of its kind all together - a construction type, which was later to become one of the classic light-weight structures and which is still used today even in a modified way. This little vault, situated on the 2 * floor, is characteristic of the builders' intention to use iron. When one stops to consider the very thin outer walls, chosen with an eye to the weak subsoil, one understands that the solution the builders found, which was to provide the mere illusion of a real Gothic vault, was their high-tech answer to create a structure without allowing the horizontal thrust of a real massive vault to endanger the walls. There were a number of other interesting structures, which are lost to us today, among them the glass roof covering the Egypt Court, which was supported by 26 wrought iron hanging trusses and which had a free span of about 15 metres. There are, nonetheless, still inumerable remarkable structures, still existing, if not in whole than in parts. The first of those whorthy of mention is the "fireproof ceiling construction composed of prefabricated cast iron beams and massive vaults which can be found on all floors in a great variety of different designs. This type of ceiling, which had been developed for industrial purposes in English and Scottish mills and warehouses around 1800, was built in Berlin on such a scale for the first time. The most interesting parts of the ceilings are the vaults which consist of various light-weight bricks or - mainly - of hollow clay pots (Fig.5). At first glance, these pots, produced in different factories nearby, may appear quite strange. They illustrate very clearly, however, the builder's intent to minimize the dead load of every part of the structure as well as of the building as a whole. The idea of integrating clay pots into the load bearing structure is a throwback to Roman constructions (as, for example, San Vitale in Ravenna) where clay tubes were used for the vaultings. Around 1800, however, one also finds them - connected with wrought iron beams! - in "fireproof ceilings in Paris dwelling-houses or, later on, in English factory buildings. The cast iron skeletal structures are also notable - arched beams combined with very thin cylindrical columns, which dominate the upper floor of the southern wing. These were to support a variety of vaultings, tunnel vaults as well as pendentive cupolas. Fig.3, which is taken from the architect's presentation of the museum in a publication dating from 1862, provides an example of the final

8 396 Structural Studies, Repairs and Maintenance of Historical Buildings shape and decoration of these skeletal structures - here in the Room of Majolicas. Fig.4 shows the working drawing of the bare cast iron structure for the same detail, and fig.5 may illustrate its actual state. Figure 7: Room of Niobides, bowstring girders, actual state, photo 1993 Perhaps the most impressive structural elements, however, are the bowstring girders, which were used as binding beams in almost all of the exhibition rooms of the northern wing and which had a span of about ten metres (Fig.2). There are still bowstring girders in three of the great rooms - in best condition in the Room of Niobides on the 1" floor (fig.7, 8, 9). Each of these girders consists of a cast iron arch, normally prefabricated in two parts, and a pair of wrought iron tie rods, forged together and rolled out to a strength of 2% inches using different single rods of best Scottish Low-Moor-Iron to even out any faults. A well graded security concept with different demands on the quality of the structural elements depending on the different risks and dangers of failure becomes manifest. The well-designed detail of the connection between tie rod and arch (Fig.9) demonstrates the high level of iron fabricating skill which Prussia's engineers had reached, trying to catch up on the lead of their British and French competition. This short survey of only some structural elements serves to illustrate that the structural innovations of Stulers design for the Neues Museum already distinguished themselves in their details. When one stops to consider, on the other hand, the importance of integrating formerly unknown cast iron and wrought iron elements for the concept as a whole we are to visualize the special conditions on-site and the central demands in terms of function:

9 Structural Studies, Repairs and Maintenance of Historical Buildings 397 the completion of the rough construction works as quickly as possible in view of the fact that the museum was originally to be opened at an earlier date, the reduction of dead load as far as possible with regard to the extremly poor foundation conditions, the subsequent minimization of the thickness (and weight) of the walls, which, given the different settlements, which were to be expected, had to be well braced and which had to be connected to the ceiling plates, and, last but not least, the design of ceiling structures with a span of about 10 metres, which had to be as light as the walls, but which were not to burden the latters with horizontal thrust, nevertheless "fireproof and as thin as possible to allow for the installation of three entire floors within the limits of a total building height which was defined by the height of the neighbouring old museum, which had only two floors! This short list of the partly inconsistent demands shows clearly: It was impossible for Stiller and his engineers to create a building like this by using any traditional structural concept. They had to find other ways and means - and they did find them in the new high-tech concept of building with iron. The use of iron, the integration of a multitude of often hidden cast iron and wrought iron structural elements, had become the inevitable condition, the conditio sine qua non, for the execution of the ambitious architectural design. For the first time, a monumental building was built in Prussia, with the highest requirements in terms of prestige, and the design of which evolved directly from the the new possibilities offered by the new cast iron and wrought iron building materials. The result was a complicated, three floor poly-structure consisting of various structural forms and room shapes and embedded in extremly light surrounding walls. Stulers architectural gesture is multilayered and full of facets. Nonetheless, Figure 8: Room of Niobides, detail of bowstring girders, photo 1993 Figure 9: Room of Niobides, end of bowstring girder, connection between wrought iron tie rod and cast iron arch, photo 1993

10 398 Structural Studies, Repairs and Maintenance of Historical Buildings it underlines unambiguously: Prussia's building technology has reached the age of industrialization. 4 Summary In many respects, the Neues Museum is a unique testimony of Prussias new art of construction and building within the context of industrialization and classicism. It first testifies to a deep change in the understanding of how to design and build an edifice; this industrial viewpoint calls for new building practices and also it generates a new type of builder - the civil engineer. Secondly, the Neues Museum testifies to the evolution of a new kind of structure, a structure characterized by the unerring use of the potential inherent to building with iron. It would have been impossible for its builders to execute the architectural and functional concept without the integration of a wide range of cast iron and wrought iron structural elements. Thirdly, the aspect of construction as an architectural challenge - an aspect into which I cannot delve here: The Neues Museum testifies to a new architectural theory, maturing against the background of industrialization, a very tectonic theory, that enabled the builders to combine classic ideals with construction methods and general building conditions at the beginning of the iron age. The Neues Museum is the only,,iron" monumental building of its time in Berlin and Prussia that still exists. It is a unique monument, the historical importance of which - technical as well as architectural - can hardly be overestimated. Today, the remaining torso calls for an architectonic answer, measured in such parameters as respect, attention to detail and the courage of its historic builders, which can enable us to react to difficult conditions by developing contemporary solutions with an eye to the future. References 1. Hoffmann, C.W., Notizen iiber die bei dem Grundbau des neuen Museums gebrauchten Transportmittel..., Notizblatt des Architektenvereins zu Berlin, pp57ff, Hoffmann, C.W., Nachricht ttber die beim Bau des neuen Museums angewendete Vorrichtung zum Auffahren der Materialien, Notizblatt des Architektenvereins zu Berlin, pp 89ff, Hoffmann, C.W., Die feuerfesten Decken des neuen Museums hierselbst, Notizblatt des Architektenvereins zu Berlin, pp 167ff, Adler, F., Das Neue Museum in Berlin, Zeitschrift fur Bauwesen, pp 23ff, 57 Iff, Staler, A., Das Neue Museum in Berlin, Verlag Ernst & Korn, Berlin, Lorenz, W: Stillers Neues Museum, Berlins Museen - Geschichte und Zukunft, ed. Zentralinstitut fur Kunstgeschichte Munchen, Deutscher Kunstverlag, Munchen and Berlin, , 1994.