The ruins of Tiwanaku (A.D. 500–950), in the modern republic of Bolivia, present an archaeological challenge owing to intense looting during the colonial period that effectively demolished the site. One building in particular, known as the Pumapunku, was described by Spanish conquistadors and travel…
Reconstructing ancient architecture at Tiwanaku, Bolivia: the potential and promise of 3D printing | Heritage Science | Full Text Your Privacy We use cookies to make sure that our website works properly, as well as some ‘optional’ cookies to personalise content and advertising, provide social media features and analyse how people use our site. By accepting some or all optional cookies you give consent to the processing of your personal data, including transfer to third parties, some in countries outside of the European Economic Area that do not offer the same data protection standards as the country where you live. You can decide which optional cookies to accept by clicking on ‘Manage Settings’, where you can also find more information about how your personal data is processed. Further information can be found in our privacy policy. Accept all cookies Manage preferences Skip to main content Advertisement Search Get published Explore Journals Books About Login Menu Get published Explore Journals Books About Login Search all SpringerOpen articles Search Heritage Science About Articles Submission Guidelines Reconstructing ancient architecture at Tiwanaku, Bolivia: the potential and promise of 3D printing Download PDF Download PDF Research article Open Access Published: 13 December 2018 Reconstructing ancient architecture at Tiwanaku, Bolivia: the potential and promise of 3D printing Alexei Vranich ORCID: orcid.org/0000-0001-8027-52121 Heritage Science volume 6, Article number: 65 (2018) Cite this article 38k Accesses 5 Citations 162 Altmetric Metrics details AbstractThe ruins of Tiwanaku (A.D. 500–950), in the modern republic of Bolivia, present an archaeological challenge owing to intense looting during the colonial period that effectively demolished the site. One building in particular, known as the Pumapunku, was described by Spanish conquistadors and travelers of the sixteenth and seventeenth centuries, as a wondrous, though unfinished, building with gateways and windows carved from single blocks. Unparalleled in the pre-Colombian New World, the craftsmanship of this masonry has long been considered the architectural apogee of Andean pre-Colombian lithic technology. Unfortunately, during the last 500 years, treasure hunters have ransacked this building to the point that none of approximately shattered remains of 150 blocks of the standing architecture are to be found in their original place. Over the last century and a half, several different scholars have carefully measured the shattered architecture and even managed to join several fragments to form complete pieces. This research revisited these historic field notes with a view to transforming this century and a half of documentation into solid 3D form. These measurements were entered by hand into an architectural modeling program; the virtual form was subsequently printed in 3D form at 4% reduced scale. Unlike large architectural pieces — or notes or models on a computer screen — 3D-printed pieces can be manipulated quickly and intuitively, allowing researchers to try combinations and seek connections rapidly, turning over pieces and testing possible fits. This tactile engagement, along with the ability to quickly try out combinations of the 3D-printed pieces, led to fresh and often unexpected insights. Once refined and simplified, this methodology, was demonstrated to the indigenous site managers who were provided with a full copy of the printed architectural fragments with a view to continuing research and to present the work to visitors, stakeholders and other scholars. BackgroundThis effort represents a technological step back from recent efforts in the virtual assembly of fragmentary data through the use of advanced computer programing, and instead denotes an attempt to capitalize on the archaeologist’s learned ability to visualize and mentally rotate irregular objects in 3D space. The case study is the highly damaged pre-Colombian monument in the high Andes of Bolivia known as the Pumapunku (Gateway of the Puma or Jaguar). The most common word used in the description of this complex ruin is “inconceivable”—a word penned in the first description of the site in 1549 [1], and that continues to be used in popular literature and by tour guides today. The intent of the project, then, was to translate the inconceivable into the conceivable, or in more precise terms, to translate the complex and cumbersome data that is difficult to visualize and test into something that both our hands and our minds could grasp. Unlike pottery or bone artifacts, which archaeologists are accustomed to handling and refitting due to their smaller size, the majority of the blocks were too large to move. To overcome this challenge, the project team tested a variety of field-recording techniques, eventually relying almost exclusively on an extensive set of archival field records from various scholars to manually input and create virtual 3D models of architectural fragments. Thereafter, the project used additive manufacturing, more commonly known as 3D printing, to create reduced and accurate models of the fragments. Having the pieces all visible and immediately accessible resulted in an engaging and non-stop process of trial and error and moments of insight that could be quickly tested on the models. Due to the quantity of ashlars that has been lost or remains unexcavated, a full reconstruction of this building is unlikely, at least for the moment; nevertheless, this research reconstructs enough of the building to understand the form of the building. Those interpretations are beyond the scope of the paper; in their place, for this publication we focus on the manner in which we can revalue previous fieldwork from the last century and created a novel, effective and non-invasive methodology of reconstructing shattered architecture that can be comprehensible to a wide range of stakeholders.SettingSimilar to the Nile River and the Indus Valley, the Titicaca basin holds the distinctions of being one of the few places on earth where civilization arose sui generis. The earliest example of public ritual architecture in the Titicaca basin, the sunken court, dates to 1800 B.C. [2, 3]. This hallmark of Titicaca architecture comes to an end around A.D. 1000, by which time an estimated 800 sunken courts had been built throughout the basin. At the site of Chiripa (550 B.C. to A.D. 100) and Pucara (200 B.C. –A.D. 300)—two of the larger and better-known sites before the Tiwanaku phenomenon—the sunken courts are surrounded by internally complex rectilinear buildings, or “houses” made of earth (adobe) and stone.In the approximate center of the southern valley of the basin lies a series of pyramids and platforms that marks the center of the ruins of Tiwanaku, occupied ca. A.D. 500–1000 (Fig. 1). Descriptions of monumental Tiwanaku focus on two zones located east and southwest of the modern town of Tiwanaku (Fig. 2). To the east sits the main core of seven stone and earth structures: the Semi-subterranean Temple, the Kalasasaya, the Putuni, the Chunchukala, the Kherikala, the Kantatallita, and the Akapana Platform (Zone 1). To the southwest lies the subject of this study, the Pumapunku, an alignment of plazas and ramps centered on a raised platform (Zone 2). The ruins challenge investigators owing both to modifications by the later mature polity, harsh weather, and the intense colonial period looting that destroyed all but the largest of features.Fig. 1Titicaca basin and the major archaeological sitesFull size image Fig. 2The primary monuments of the site of TiwanakuFull size image The ruins have played a major role in historic and mythic narratives of the various states and empires that have controlled the area [4]. The Inca repurposed the ruins as their place of birth; the Spanish assiduously went about destroying it; the developing mestizo classes that it was indeed built by the Inca Emperor attempting to recreate Jerusalem [5]. During the wars of independence from Spain, the famed Gateway of the Sun was reset in a standing position to mark the start of a new order. After independence, the ruins appeared as part of the tug of war between the two major cities—La Paz and Sucre—vying for the ideological justification to serve as the seat of the newly formed republic of Bolivia.In the mid-twentieth century, an ambitious effort was started to create an impressive set of ruins that would rival Machu Picchu in Peru, and Teotihuacan in Mexico [6]. Any monumental site across the basin, and even across the southern Andes, was assigned as a satellite or outpost city of an imagined Tiwanaku empire [7]. At the ruins themselves, an extensive program of excavations and heavy-handed restorations transformed the picturesque vestiges of eroded stone into its present over-reconstructed state. Entire sections of architecture were removed and reset to give the site a more monumental feel in line with the nationalist narrative of a pre-Columbian empire of similar proportions and size to the later Inca Empire [4]. As a result of these unfortunate interventions, the ruins also hold the distinction of being considered one of the worst reconstructed sites in the continent [8]. Nevertheless, the ruins became an obligatory visit by international travelers and indigenous and mestizo nationals, each who brought their own agenda and interpretation [9]. In particular, the solstice festival, restarted in the 1980s after a short period of revival in the mid-twentieth century, brought the ruins international attention, and local interest as the local indigenous peoples used the ceremony both as source of income, and identity. The festival developed from a small gathering into a well-organized event hosting thousands, and could be argued that the election of the first indigenous president—and his inauguration at the ruins themselves—were made possible by the yearly gathering what would become his solid political base [10].This period of politically driven rushed excavations and heavy-handed restorations has, for the most part, come to an end, but the situation at the ruins remains just as complicated with the decentralization of power from the central government to the regions and provinces. In 2001, the indigenous communities took over the ruins and expelled all the central government workers [11]. Over time, relations have improved and there is a higher degree of collaboration between the indigenous rural authorities and national and international organizations. Nevertheless, the majority of the stakeholders at the site are not archaeologists or academics, but those who occupy a range of traditional, local, and national political positions. As well intended as they may be, this diverse group of stakeholders has a limited understanding of the conventions of conservation and proper management of a World Heritage Site. Even under the best of circumstances, academic publications and thick government conservation reports have little impact on the debate of how to preserve, restore, and maintain the site, and discussions between the stakeholders rarely find common language. For example, in 2006, the stones of the Pumapunku were rearranged as part of a project ordered by the interim president of the country to “fix” the site during his short tenure. The large sandstone slabs were leveled and several blocks were reset, but both their location and arrangement are incorrect according to easily accessible publications [12].The PumapunkuThe first known plan-view of the temple complex, made in 1848 by Léonce Angrand, places fragmentary remains of four concentric revetments around a raised platform [13]. Beginning in the mid 1970s, a series of excavations confirmed the remains of these concentric revetments of true horizontal coursing [14], along with a wide, worn set of sandstone stairs on the west side [15,16,17]. The footprint of the platform is T-shaped, extending 167 m along the west side, and 116 m along the north and south sides. The wings of the “T” extend out 27 m and are estimated to be 20 m wide [18, 19] (Fig. 3). The partially dismantled exterior revetments of the platform attest to the sides and the base of the ashlars being completely finished before being set in their respective courses. Fitting perfectly front to back, the entire course was ground down to form a continuous flat, true horizontal course.Fig. 3Topographic and plan view of the PumapunkuFull size image This research focuses on the east side of the platform, an alignment of large sandstone slabs surrounded by a tumble of intricately carved andesite blocks (Fig. 4). Astonished by this impressive collection of shattered and overturned architecture, several Spanish chroniclers of the sixteenth and seventeenth centuries left us with descriptions of wondrous, though unfinished, gateways and other interesting carved blocks that sat upon and around cyclopean sandstone stone slabs [1, 20, 21]. Architectural studies have confirmed the early observation that both the andesite architecture and sandstone slabs were unfinished [1, 12, 20, 22,23,24,25]. By the early 1600s, it appears that only one gateway and a “window” remained in place, and these may have remained standing until the mid-1700s. For the most part, the early colonial descriptions prior to the complete destruction of the standing andesite architecture convey a sense of awe rather than a specific architectural form; later descriptions provide a few additional insights—and a great deal of speculation—on what is by the nineteenth century a heavily damaged structure [26,27,28,29,30].Fig. 4Historic photograph of the architecture on the east side of the Pumapunku platform taken by Max Uhle in 1893Full size image There are two basic elements of this structure: sandstone slabs that served as the foundation, and andesite blocks that were superstructure. For the former, there are 17 pieces of sandstone defining a flat 6.75 by 38.72 m area (Fig. 5). The remarkable aspects of the sandstone slabs—their size, their smooth surfaces—have drawn comments for several centuries. In fact, the largest sandstone slab-measuring 8.12 by 3.86 by 1.2 m with an estimated weight of 83 tons—has been paced out several times over the centuries, unfailingly educing a corresponding level of awe and wonderment on the origin and manner of transport of this tremendous stone. The other crucial element of the stone slabs for this study are recessed geometric outlinesFootnote 1 that, based on in situ architecture in other locations on the site, were the meeting point or bedding for standing architecture.Fig. 5Drawing from 1848 by Leonce Angrand of the sandstone slabs. Notice the geometric outlines carved into the slabs that once held standing architectureFull size image The second element of this building features approximately 150 separate pieces of finely cut andesite blocks scattered around these sandstone slabs (Fig. 6); several more can be found further afield across the site and in the local museum. This stonework is characterized by planar surfaces, geometric form, precise edges, and internal right angles. Their sizes range from geometric blocks that can be easily lifted by a person (34 by 26 by 14 cm, for an estimated weight of 8.5 kg), to the much heralded “H” stones (97 by 99 by 55 cm for an estimated weight of 600 kg), to the iconic gateways carved from a single block measuring slightly under three meters tall, with an estimated weight of 9 t (see Fig. 12). One particular andesite block measures 3.5 by 3.2 by .64 m for an estimated weight of 20 metric tons, a tremendous size especially when one considers that the quarry was located on the other side of the lake [31, 32].Fig. 6Andesite blocksFull size imagePrinciples of Tiwanaku masonry and architectureArchaeologists and conservators working on classical period monuments have the advantage of access to a detailed corpus of written documents, graphic representations, and a continent of well-preserved analogs. The reconstruction of a ruined monument, for example the Acropolis in Athens, has its set of challenges, but at least the individual fragments—say, for example, a capital or a fragment from the cornice—can be recognized, as would their general position within the larger structure.Unfortunately, Tiwanaku is firmly embedded within a pre-literate past with little hope of the discovery of indigenous writings on the thoughts and ideas of the builders. There is no standing architecture beyond foundations at the site that can serve as an analog. An unknown number of blocks are missing, and to further complicate matters, the Pumapunku was never completed, which means that we are essentially attempting to reconstruct the unwritten intent in the mind of an architect from over a millennium ago. As a result, reconstructions of this building remain hypothetical if not somewhat speculative (see Sangines 1970 for a series of drawings [33].Earlier scholars had joined several fragments to form complete pieces, most notably in the case of the gateways [22, 34]; and the presence of moldings and clamps demonstrated how these gateways were intended to be part of larger architectural context [12] (Fig. 7). Additionally, several generations of observations and studies, on the other hand, have deduced a series of architectural rules that govern the overall form and design of the building. For example, since many of the blocks are perfect replicas of each other, including left and right-hand versions of the same form, repetition and symmetry were part of the design. In addition, the dimensions and proportions of the ubiquitous niche or gateway motif were determined by a mathematical ratio [35].Fig. 7Virtual reconstruction of a gateway and the projection of the adjoining wallsFull size imageOne unique aspect of Tiwanaku masonry that facilitated reconstruction was that the andesite blocks were also completely dressed and finished before being set in place through the use of hoisting grips that were intricately carved through the andesite. This arduous and challenging task allowed the block to be lowered slowly without damaging the precise friable edge, resulting in a perfect right angle between the block and the floor. Elaborate decorative friezes would span several ashlars; however, unlike in other parts of the world where these finer details would be carved after the blocks were assembled, the Tiwanaku masons completed each ashlar, including the carved frieze, before assembling the structure [12]. Consequently, this unique construction method meant that even if the structure was never actually assembled, a virtual anastylosis, based on reconnecting the frieze and other decorated elements, was indeed possible.The precision of the mortarless joints allowed a few blocks to be reunited with their likely neighbors [22]. Architect JP Protzen managed to make several more refits, but one of his more significant was his realization that the much-admired carved block known as the “Escritorio del Inca” (Desk of the Inca, henceforth to as Model Stone 1) was an accurate and reduced-scale model (.5774) of a full-scale architectural form (Fig. 8) [35]. Forming an architectural “Rosetta stone,” the proportions and relations of the carved ornamentation served to justify joining several andesite blocks to form an architectural composition. Though these and several other blocks have been refit, as of yet, we still lack a view of a complete structure. In particular, the relation between the andesite blocks and the sandstone slabs has still to be established. Protzen cautiously suggests that the architectural composition he reassembled may have flanked either side of a gateway.Fig. 8Model Stone 1 on the left, its individual components in the middle, and its projection into full size arch… truncated (54,170 more characters in archive)