Changes to physical and mechanical properties of pyroclastic flow deposits occur during welding process, resulting from overburden pressure and temperature. A great deal of research has been carried out to identify which physical parameters can enable quantification of the degree of welding within pyroclastic deposits. Material properties, such as density, porosity, hardness, abrasion, and compressive and flexural strength, are critical in assessing the suitability of natural stone as a building material, but they have not been sufficiently integrated. Therefore, an attempt has been made to develop a welding classification which integrates measurements of material properties with petrographic and textural observations. The proposed classification covers physical, index, and strength parameters for pyroclastic flow deposits. The most important aspect of this investigation has been the quantification of material parameters and definition of a welding classification applicable to a wide range of ignimbrites, from nonwelded to densely welded, that are used as natural building stone. This welding classification is proposed to ensure a consistent approach in characterizing key aspects of welded facies in pyroclastic deposits and in the identification of natural stone reserves.

由于覆盖压力和温度的影响，火山碎屑流沉积物的物理和机械性能发生变化。为了确定哪些物理参数可以量化火山碎屑沉积物中的焊接程度，已经进行了大量研究。诸如密度，孔隙率，硬度，耐磨性以及抗压和抗折强度之类的材料特性对于评估天然石材作为建筑材料的适用性至关重要，但尚未充分整合。因此，已经尝试开发一种焊接分类，其将材料性能的测量与岩石学和组织学观察相结合。拟议的分类涵盖了火山碎屑流沉积物的物理，指数和强度参数。这项研究最重要的方面是材料参数的量化和焊接分类的定义，这些焊接分类适用于从天然和天然石材中使用的各种火成岩，从非焊接到密集焊接。提出这种焊接分类方法是为了确保采用一致的方法来表征火山碎屑矿床焊接相的关键方面以及鉴定天然石材储量。