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Full base shear seismic demand analyses with calculated examples for heavy stone masonry buildings are not present in the literature. To address this shortcoming, analyses and calculations are performed on nominally reinforced rubble stone masonry house and school designs, as typically built in Nepal. The seismic codes are literally applied for countries where the technique is still allowed (Nepal, India, China, Tajikistan, Iran, Croatia), or should be reintroduced based on current practices (Pakistan, Afghanistan, Turkey). First, this paper compares the base shear formulas and the inertia forces distributions of these codes, as well as material densities, seismic weights, seismic zoning, natural periods of vibration, response spectra, importance factors and seismic load combinations. Large differences between approaches and coefficients are observed. Then, by following Equivalent Lateral Force-principles for Ultimate Limit State verifications (10%PE50y), the base shear and story shears are calculated for a design peak ground acceleration of 0.20 g, as well as the effects of critical load combinations on the forces and moments acting on the lateral-resisting elements. It is concluded that Pakistan has the most tolerant code, Nepal represents an average value, whereas India and China are most conservative toward the case study buildings. Overall, it is observed that heavy-masonry-light-floor systems with negligible diaphragm action behave different under seismic motion than most other building typologies. Given the observations in this paper, the applicability of conventional ELF, S-ELF and S-Modal methods for heavy masonry buildings is questionable. The codes however do not introduce modified approaches that address these differences. Possible implications of the exclusion of plinth masonry and large portions of seismic weight need further assessment and validation, for which different (possibly more sophisticated) concepts must be considered, such as the equivalent frame method or distributed mass system. Since Nepal allows stone masonry in areas with higher seismic hazard levels >0.40 g (opposed to India

Nearly 325 seismic and masonry codes from all over the world have been analyzed, of countries where stone masonry was, or still is, abundantly practiced. This paper compares and summarizes design specifications and construction requirements, with a specific focus on “nominally reinforced rubble stone masonry (NRM) with cement mortar and wooden diaphragms in seismic areas.” Currently, the technique is only allowed and described in some detail in the codes of Nepal, India, China, Tajikistan, Georgia, Iran and Croatia. It is concluded that the design specifications vary greatly without any consensus on the main sizes, dimensions or details. This raises questions about the completeness and correctness, as well as the reliability and actual value of the knowledge in this field. It is further observed that types of stone masonry and stone properties are seldom clearly described in the codes. It is also noted that several countries where stone masonry is still broadly practiced, are currently not allowing the technique (or have no codes in place), such as Afghanistan, Pakistan, Bhutan, Azerbaijan, Kyrgyzstan, Morocco, Tunisia, Turkey, Yemen and Albania. This, however, does not serve the current engineering practices and construction needs in these countries. To address all shortcomings, the paper recommends clear descriptions and terminology; the international adaption of NRM as a fourth masonry category; and the development of a stand-alone code specifically for this technique. Therefore, the authors propose a full assessment, validation, optimization and complementation of the existing knowledge, by means of the current state-of-the-art for calculating, testing and modeling. This envisions a structured research approach with focus on vernacular and traditional construction techniques, called “Non-Engineered 2.0,” for which a research initiative is started under the name “SMARTnet,” meaning “Seismic Methodologies for Applied Research and Testing of non-engineered techniques.” The findings of this paper will serve as the starting point for the upcoming follow-up paper, which will complement the seismic demand with hand-made base shear calculations for countries that still allow the technique. The paper ends with an appeal to experts, academics and final-year students worldwide, to exchange their knowledge and to support the project with their time and expertise.

The use of “ductile seismic frames”, whose proper seismic behavior largely depend upon construction details and specific design rules, may do not always lead to effective seismic resistant structures, as dramatically denounced by the famous Chinese artist Ai Weiwei in his artwork Straight. The artwork (96 tons of undulating metal bars that were salvaged from schools destroyed by the 2008 Sichuan, China earthquake, where over 5,000 students were killed) is a clear denounce against the corruption yielding to shoddy construction methods. The issue of safe constructions against natural hazards appears even more important in developing countries where, in most cases, building structures are realized by non-expert workers, or even by simple “people from the street”, who does not have any technical knowledge on construction techniques and seismic engineering. In the present paper, a brief history from the first frame structures to the more efficient wall-based structures is provided within earthquake engineering perspectives. The superior structural properties of box-type wall structures with respect to conventional frame structures envisage a change of paradigm from actual “ductility-based” Earthquake Engineering (centered on frame structures) towards 100% safe buildings through a “strength-based” design exploiting the use of box-type wall based structures.