With an air of simplicity and wisdom, engineer Julio Vargas Neumann welcomes us. His two dogs accompany us as we descend after the necessary ascent to enter, and we are also accompanied by the stone walls defining the lot. We sit down and begin - or continue - the interview and conversation regarding the value of 'shicras', local materials, and earth construction. We also discuss criticisms of cement, aluminum, and steel, as well as perspectives on the future of materials in Peru and the world. Likewise, we delve into the long-neglected and recurrent rural problem in South America, discussing the inexorable need to change paradigms and priorities.
Julio Vargas embarked, unexpectedly, on a professional path as a civil engineer following a casual conversation with his schoolmate, Jorge Solís Tovar—who later became an engineer, professor, and authority in the field. With conviction, Solís suggested that due to Vargas's natural aptitude for the more challenging virtues, specifically mathematics, he should start his studies at the Faculty of Engineering at the Pontifical Catholic University of Peru, instead of pursuing his initial inclination to study medicine. At that time (1963), 'La Católica' only offered a civil engineering program. With Vargas eventually becoming part of the faculty and soon becoming the first Department Head, in collaboration with professors and friends, they decided to incorporate the teaching of other career paths that would begin to transform their existing paradigms. In this trajectory, the 1970 Huaraz earthquake marked a turning point. The extremely high death toll became a pivotal moment, prompting a realization that many tasks needed to be undertaken in the country.
So, what we've belatedly discovered is that after less than 100 years, reinforced concrete starts to crack and deteriorate, despite attempts at permanent repairs - Julio Vargas Neumann
The models and materials of traditional housing were called into question, and a focus on change gained special relevance due to a political moment framed within General Velasco's government. Vargas points out that priority began to be given both to academic efforts in education through the Ley Orgánica de Educación (Organic Law of Education) and to social responsibility towards the rural population of Peru, an enormous number of people living in vulnerable houses constructed with earth or stone but lacking the necessary construction qualities demanded by Andean seismic activity.
From that moment on, in collaboration with many professors and professionals, work began on researching the appropriate and enhanced use of natural and local materials. This endeavor started bearing fruit with the development of various state guidelines and standards (1977) related to earth architecture. These guidelines were soon acknowledged in global publications and other international regulations, such as those published by the IAEE (International Association of Earthquake Engineering) based in Japan. Before the Peruvian contribution, these publications had not previously included sections on spontaneous architecture using raw earth constructions. They also lacked declarations for the conservation of Cultural Heritage built with natural materials, such as the Lima Declaration, signed by Peruvian and Japanese professionals in 2010. This declaration is disseminated and recommended by the UNESCO-affiliated body, ICOMOS (International Council on Monuments and Sites), along with other research and innovations promoting constructions made of earth and stone. This profound research and action continue to this day, largely due to the establishment, in collaboration with architect Sofía Rodríguez Larraín, of the Centro Tierra (Earth Center) at the Pontifical Catholic University of Peru.
What have we done as a civilization? We've recklessly damaged the global environment in the name of so-called progress with two inconvenient and poorly researched polluting materials - Julio Vargas Neumann
Julio Vargas, engineer and a global reference in seismic knowledge and construction using ecological, natural, and local materials, holds significant national and international honors, such as the Order of Peruvian Engineering and the National Prize for Culture in Applied Sciences and Technology in 1985/86. In the following excerpt from the interview, he shares his opinions on the use of cement, steel, aluminum, and how these industrial materials—and their persistence—contribute to the 'poisoning' of our planet. He contrasts this with the potential advantages that improved natural and local materials, along with innovations, could offer. Additionally, he provides insights into sustainable paths and the roles we could assume in the face of the uncertain future of the Earth.
Diego Vivas (DV): How do you imagine it’s possible to think about the future of construction materials in Peru? What aspects do you think need strengthening or changing?
To provide a good and engaging overview, I believe we can trace back the events of the past 100 years worldwide and in Peru. Belatedly, we're beginning to understand and learn to do things that some more developed countries have been doing. Not merely through imitation but by influence and conviction. So, what has happened in the developed world from the industrial development and the emergence of seemingly efficient, durable, and more resilient new materials? These modern materials have brought about a shift leading to the exorbitantly costly steel, the even more expensive aluminum, and the lesser-known cement, perhaps less costly but more 'polluting' for the environment. The latter accounts for 8% of global carbon dioxide emissions, which, in turn, represent 81% of the greenhouse gases that are uncontrollably warming the planet and causing irreversible climate change.
JVN: The commitments made by the signatory countries of COP20 in Paris and previous agreements are not being fulfilled. For now, few have real awareness. We've massively invaded the world with millions upon millions of square meters of 'wonderful' reinforced concrete, meaning cement and steel. The latter, in smaller quantities but much more complicated for the environment. So, what we've belatedly discovered is that after less than 100 years, reinforced concrete starts to crack and deteriorate, despite attempts at permanent repairs. The steel rusts due to the porosity of the concrete. Air seeps in and oxidizes the iron reinforcements, potentially increasing their volume up to 11 times, breaking and damaging the concrete. This is already happening globally, especially evident closer to the sea due to the moisture that accelerates the process.
We cannot make the mistake of transporting the harmful cement to rural areas, and paying for its transportation on top of that - Julio Vargas Neumann
JVN: So, now... What can we do? The world is flooded with reinforced concrete structures that won't last 100 years. No one thought that the timeframe was too short. If we carefully consider what's happened, the concrete that initially arrived in Peru will soon be of no use. When we look at our older buildings, especially those closer to the sea, they already have cracks. By 50 years, the issues start surfacing. Attempts are made to repair them, but the entire building is already compromised and condemned to a miserable 20 or 30 years of life. There will come a time when it'll be difficult to continue living in these structures. So... What have we done as a civilization? We've recklessly damaged the global environment in the name of so-called progress with two inconvenient and poorly researched polluting materials. And now, we're seeking other types of expensive 'xxxconcrets,' mixes of new materials that necessarily need to be more durable and eco-friendly, but we don't even know their costs yet. We're becoming aware that we've globally made a very serious mistake. Let's hope to innovate and create sustainable solutions. We have the task of replacing materials ahead of us, but there's little awareness in our generations about this problem.
Heritage isn't assessed by today's aesthetic values, but by its representation over time, revealing life and conveying a message from ancient times, narrating the human activity of that era to communicate cultural value - Julio Vargas Neumann
JVN: We have an obligation to prioritize the study of new materials, such as everything related to earth construction, a natural and locally sourced material with many beneficial properties. The other day, we made a list of the advantages of building with earth and found 22 significant reasons why earth construction was magnificent. Beyond the costs, local materials, and recyclability... adobe can endure many cycles, offers thermal and acoustic advantages, and preserves the local climate within the house. The benefits are incredible, yet there's a disregard for rustic materials compared to modern materials like the famous concrete, which seems better due to its strength and presumed durability. However, as we'll explain, this is not true. They are, in a way, only temporarily more resistant.
JVN: We need to study and reinforce earth constructions to ensure they don't jeopardize people's safety. That's the surmountable weakness they represent. Noticeably, during earthquakes, unreinforced earth constructions suffer damage. So, earth construction is possible, but always with reinforcements... until we reach a stage with 'Shicras'! They have the advantage that they only require an additional effort for reinforcement, modifying the foundation... or better yet, just the superstructure. With this, the entire construction is saved because it receives much less energy from earthquakes. It's even better if we combine both aspects. We isolate ourselves, partially dissipating seismic energy, and experiencing a less damaging earthquake, and additionally, we implement appropriate reinforcements for added safety. This way, we solve the seismic problem in rural areas, which represent 30 to 40 percent of the Peruvian population, those who need it most.
DV: And are there, in that sense, ways to propose new horizons in the Peruvian panorama concerning these materials?
JVN: I think it's our task. To recommend only the materials we can appreciate and be sure are advantageous and convenient... to promote them. We cannot make the mistake of transporting the harmful cement to rural areas and paying for its transportation on top of that. It's a sin, in terms of costs and planetary conservation. We're bringing the expensive enemy to the rural areas, which are the most impoverished. We can't contribute to accelerating climate change through construction materials.
I believe the world won't revert to using solely natural materials. My impression is that there will be a balanced use of both natural and manufactured materials. The reinforced concrete of today will vanish, not due to sand or stones, but because of Portland cement - Julio Vargas Neumann
DV: What challenges do these new series of policies or ways of thinking present at a local or regional scale?
JVN: Unfortunately, the day-to-day tasks prevent government agendas from giving importance to what we've discussed today. Rural areas will continue to receive the least attention because they are there and not here. The problem of absence and worse, the use of inappropriate materials, will persist, and there will continue to be visible repercussions. We must break the lack of concern and not remain indifferent. But in reality, it's a task that should start with those who know and not with those who still don't know. So, it's us who are obliged. It's an immensely important social task.
DV: Is that the same in the Andes, in the Andean countries?
JVN: What has been done in Peru as a pioneer, and gradually in the Andean countries, is being carried out in other neighboring nations. Much of what is known is also being implemented in Chile. There isn't a regulation that permits building with earth, but there is a regulation allowing the reconstruction of earth heritage, a task in which I was involved, providing all the research and experiments we had conducted in Peru, which they hadn't done about ten years ago. There's a standard on how to repair, rebuild, and restore heritage constructions with earth in Chile, preserving their heritage value. Heritage isn't assessed by today's aesthetic values, but by its representation over time, revealing life and conveying a message from ancient times, narrating the human activity of that era to communicate cultural value.
JVN: As mentioned in Chile, we've had significant collaborative activity, and the same is happening in Colombia, where a regulation is being developed. In Ecuador, the Peruvian standard is being used, and in general, Peru's influence in Latin America is quite strong... even in Mesoamerica. We've had substantial research connections with Mexico; we've always assisted each other, although we have some differing perspectives, such as the acceptance or rejection of solid earth roofs without reinforcement, using guidelines for single or double curvature. The colonial constructions, primarily in Lima, were destroyed in the earthquakes of the seventeenth and eighteenth centuries. They've had modern experiences in the southern part of their country. We've managed to reach the same level as the ancient experiences of our Central and South American neighbors, sharing knowledge. For instance, in Bolivia and northern Argentina, construction is also guided by the Peruvian standard. The Design and Construction Standard for Reinforced Earth in Peru (Norma de Diseño y Construcción con Tierra Reforzada del Perú, 2017) may not be considered an international standard, but perhaps a very useful informational text in Western and Southern America, which are highly seismic zones.
The Design and Construction Standard for Reinforced Earth in Peru (2017) may not be considered an international standard, but perhaps a very useful informational text in Western and Southern America, which are highly seismic zones - Julio Vargas Neumann
DV: You have mentioned a bit about the impact scale of the earth construction standard. What are the main projects you've worked on or are currently working on that contribute most to the future of materials construction?
JVN: Particularly, I would like to delve into research work that achieves two objectives. The first would be to investigate learning or how to create and innovate equipment with laboratory tools for cutting-edge studies, such as our costly earthquake simulation table, currently the best in Latin America. The second would focus on deepening the understanding of seismic energy dissipation in construction prototypes using natural rural materials in different regions of the country.
JVN: The origin of this extensive research, which I still consider incomplete, wasn't ours, but that of the people from the Caral civilization. They developed significant knowledge through the use of shicras filled with medium-sized stones to transport them from the quarry to the pyramid construction site. The invention of the shicras' behavior, based on energy dissipation, is truly extraordinary and applicable to a future they couldn't have known or predicted. It's an ancient innovation of tremendous value, with immense significance in preserving and safeguarding lives in our highly seismic territory. A genuine life-saving invention of immeasurable value, even in terms of ecosystem, nature, and economics. It's an invention that we must admire with the aid of today's technologies.
JVN: Currently, we're collaborating with a small group of our former students who are studying abroad and are keen on further perfecting the dynamic vibrational behavior and seismic energy dissipating properties of the shicra system. They're forming teams with their current professors, striving to develop a better understanding of the dynamic behavior of shicras. This is because they act as isolators. The stones, tied with a mesh of strings, do not shift when placed in the foundation. They don't roll but pivot and remain in place due to the tying. This capacity to not shift but rotate, producing movements under very strong loads, results in significant seismic energy dissipation. It's an effort that reduces seismic energy so that the stones primarily rotate rather than shift, passing less energy upwards and resulting in a less severe earthquake impact. This knowledge requires refinement. Only a valuable confirmation has been made through testing on the shaking table.
JVN: With the improved use of river stone-filled shicras in ellipsoid forms, we've finally prevented the tested house walls from breaking under strong unidirectional earthquakes. At most, a very fine fissure, repairable through known methods of injecting fluid earth grout, could occur instead of shattering into pieces. This was the case when there was no isolation such as shicras and river stones. The solution is highly cost-effective, and we must refine it—perhaps in a short time—and thoroughly understand its dynamic behavior for dissemination... to explore if we can enhance this simple yet more efficient application. What will we achieve? We still don't know.
DV: And from those perspectives, how do you see the future of materials in Peru and the world?
JVN: I believe the world won't revert to using solely natural materials. My impression is that there will be a balanced use of both natural and manufactured materials. The reinforced concrete of today will vanish, not due to sand or stones, but because of Portland cement. Cement is what harms the planet... what needs to be eliminated is the use of cement. We should seek other binding materials that are less aggressive to the planet. More crucial than earthquake-resistant engineering is caring for the planet due to climate change. We must aid by innovating and creating our materials. However, the capacity for inventing new materials in less developed countries is evidently lower. It is more likely to occur in the developed world, where better talent and economic resources can be assembled. Urgently, we must replace the polluting cement.
DV: And what role do we play from our latitude?
JVN: Unfortunately, due to educational levels, economic constraints, and investment limitations for research and innovation, I don't believe we'll be the ones to discover ideal solutions, but we will collaborate on them. However, we must make it known in the country that current reinforced concrete is a disaster. The constructors of modern buildings... hopefully, they become aware that these structures will only last for less than 100 years, and for the sake of fairness, they should disseminate this information. Let them report that eventually, a property owner will have to destroy and dispose of it! Hopefully, a way will be discovered to repurpose them as raw material for new construction projects. Attempts were made to solve these newly discovered issues by using expensive epoxy paints, preventing the reinforcement from being exposed to oxygen. However, the costs were enormous, and no one wanted to acknowledge the past unknown mistake.
JVN: In the future, reinforced concrete will never be used to construct buildings again as long as Portland cement is employed. A better, planet-friendly material must be discovered and utilized. As a country, we have fewer possibilities to aid in the universal solution, but we can and must assist in solving rural and vernacular issues by employing our natural materials there. Bringing attention to the problem, addressing it there, among the population, among farmers, shepherds, and locals. They can and should improve their living conditions. Today, science and technology are seen through research and laboratory testing, attempting to utilize new knowledge beneficial for the future of farmers, who can make swift progress where the material plays a crucial role. Construction with natural materials like earth, stone, wood, reeds, straw, and others, blended in new mixed techniques.
As a country, we have fewer possibilities to aid in the universal solution, but we can and must assist in solving rural and vernacular issues by employing our natural materials there. Bringing attention to the problem, addressing it there, among the population, among farmers, shepherds, and locals - Julio Vargas Neumann
DV: Is there an approximate figure you can provide regarding the number of people living in earth architecture?
JVN: In Peru, approximately 30 percent live in earthen constructions, and about 40 percent live and/or work in earthen buildings. 40 percent of the population deserves a bit more attention. Hence, the discovery of seismic dissipation using shicras and stones is incredibly significant. We must delve deeper into this. We are gaining a better understanding of the theoretical dynamic behavior to enhance this knowledge that has served us well. We're seeking river stones of consistent sizes resembling ellipsoids that, instead of displacing, rotate when they move because they're tied together. The ellipsoid's head, for spinning, lowers but raises the weight with its back part. The next instant, it reverses. Moreover, earthquakes have changing directions, so this effectively aids in spending energy through rotation. It's a machine built for this purpose. This is extremely important.
DV: What message would you like to pass on to current engineering and architecture students and professionals?
JVN: Let's see ourselves as a thinking group that can influence solutions to the massive and important problems of the country and, on a smaller scale, possibly of the world. The concern of academia should be linked to social solidarity; all of us experiencing these confusing phases of governance are Peruvians, and we must be more united than ever to prevent the country from being scattered due to corruption and lack of education. We need to act effectively and now. We're yet to know the best and most intelligent way to address the material situation, but a change must be sought... and it has to be swift.
The author thanks Engineer Julio Vargas Neumann for his time and review, and Architect Sofía Rodríguez Larraín and the entire team at Centro Tierra PUCP for their support in documenting this interview.
