Investigating Surficial Alterations of Natural Stone by Ultrasonic Surface Measurements
Investigating Surficial Alterations of Natural Stone by Ultrasonic Surface Measurements
复制标题
通过超声波表面测量研究天然石材的表面蚀变
DOI：
--
复制
发表时间：
2017
期刊：
影响因子：
--
通讯作者：
C. P. Presicce
中科院分区：
文献类型：
--
作者：
T. Meier;M. Auras;M. Fehr;D. Köhn;L. Cristiano;R. Sobott;I. Mosca;Hans Ettl;Felix Eckel;Tim Steinkraus;E. Erkul;D. Schulte‐Kortnack;K. Sigloch;F. Bilgili;Elena Di Gioia;C. P. Presicce
建筑物和纪念碑的表面对其外观和保护至关重要。通常，表面是精心设计的，与物体的用途密切相关。此外，它还载有关于建造者的艺术和技术技能的信息。然而，它也容易风化和变质。仔细修复历史建筑和纪念碑表面的先决条件是彻底分析表面的改建。定量测量支持目视检查，但对物体最上面几厘米处的材料特性进行无损表征是一个挑战。在这里，超声波表面测量的潜力，天然石材的表面蚀变的量化证明了正演模拟，实验室测试和案例研究。的基本瑞利模式示出占主导地位的波形的情况下，表面测量。它对剪切波速度随深度的变化和剪切波传播的滞弹性阻尼的变化很敏感。我们报告超声波表面测量在大理石（海王星，公园Sanssouci，波茨坦），砂岩（Porta Nigra，特里尔），凝灰岩（Campidoglio，罗马）的外墙。平均瑞利波速度与测量的P波速度大致成比例，并且与最高厘米处的物体的整体状态有关。瑞利波群速度表明材料性质随深度的变化，波形反演允许估计剪切波的速度和阻尼的深度分布。说明了天然石材风化的强烈变异性。
The surface of buildings and monuments is essential for their visual appearance and their protection. Usually the surface is carefully designed and strongly related to the purpose of the object. Moreover, it is carrying information on the artistic and technical skills of the builders. It is however also prone to weathering and deterioration. A prerequisite for a careful restoration of the surface of historic buildings and monuments is a thorough analysis of surficial alterations. Quantitative measurements support visual inspections, but nondestructive characterization of material properties in the uppermost centimeters of an object represents a challenge. Here, the potential of ultrasonic surface measurements for the quantification of surficial alterations of natural stone is demonstrated by forward modeling, laboratory tests, and case studies. The fundamental Rayleigh mode is shown to dominate the waveform in the case of surface measurements. It is sensitive to changes in the shear wave velocity with depth and in anelastic damping of shear wave propagation. We report on ultrasonic surface measurements at facades made of marble (Neptungrotte, Park Sanssouci, Potsdam), sandstone (Porta Nigra, Trier), and tuff (Campidoglio, Rome). Average Rayleigh wave velocities are roughly proportional to measured P-wave velocities and are related to the overall state of the object in the uppermost centimeters. Rayleigh wave group velocities indicate changes in the material properties with depth, and waveform inversions allow for estimating depth profiles of velocity and damping of shear waves. The strong variability of weathering of natural stone is illustrated.