Structural Health Monitoring and Assessment of Seismic Vulnerability of Historic Monuments on the Great Silk Road Based on Laser Scanning

Abstract

The high-definition laser scanning technology is used in an extensive ongoing structural assessment of historic monuments in Uzbekistan. The laser scanning studies were conducted in Tashkent, Bukhara, Samarkand and Shakhrisyabz. As a representative sample, the research results based on data obtained in Samarkand and Shakhrisyabz are discussed herein. Samarkand is one of the oldest inhabited cities in Central Asia. Because of its strategic location on the Great Silk Road, an ancient trade route between China and the Mediterranean, Samarkand was one of the greatest cities of Central Asia. Shakhrisyabz is located in southern Uzbekistan approximately 80 km south of Samarkand, Uzbekistan. Once a major city of Central Asia, it is primarily known today as the birthplace of the 14th century Turco-Mongol conqueror Timur. The scanned monuments are on the UNESCO World Heritage List. To monitor the buildings’ possible settlement due to poor soil conditions, special high-resolution laser targets were permanently installed. A detailed finite element model of monuments was generated from the as-found geometry captured by laser scans. The physical properties of the monuments were investigated by material tests of the major components recovered from the historic sites. The calibrated numerical models were used for comprehensive seismic analysis of the monuments. To monitor the structural health of the monuments, they were repeatedly scanned in order to estimate whether the structural degradation is progressing. Based on the results of numerical simulations and health monitoring results, recommendations on further preservation of the historic monuments were developed.