Bricks, Mud and Lime Mortars in Heritage Restoration: A case study

¹ Kathmandu University Department of Civil Engineering, Dhulikhel, Nepal
² Kathmandu University Department of Music, Tripureshwor, Nepal
³ Kathmandu Valley Preservation Trust (KVPT), Patan, Nepal
⁴ Manmohan Technical University, Morang, Nepal

^* pooja.amatya@ku.edu.np

Abstract

This paper is based upon an extensive eight-year experience in the restoration of monuments from the World Heritage Site Patan Darbar Square to Tripureshwor Mahadev Temple, Sattals, and Garden Area and the Sama Center, representing historically significant Malla, Shah and Rana period architectures respectively, after the Gorkha earthquake of 2015. These monuments date back from 6th to the 20th century. All structures employ a masonry system as the structural system. The main materials observed in these heritages were burnt clay bricks, stones, mud mortars, and lime mortars. This study examines the technical aspects such as material properties (compressive strength, bending strength, mechanical properties), and composition of mortars according to their use in different locations and types of structures, even within the same building. The study acknowledges the Department of Archaeology’s preservation and monument act, highlighting the potential for material reuse in heritage restoration. The primary aim of this study is to comprehensively understand and analyze the strength of antiquated materials and traditional mortars used in historical construction and restoration. It provides practical recommendations for future preservation efforts.