圆明园舍卫城城墙夯土工艺的科学分析

Scientific Analysis of Rammed Earth Process of Sravasti Wall in the Old Summer Palace

为了探究圆明园舍卫城城墙夯土工艺,采用X射线衍射(diffraction of X-rays,XRD)分析、激光粒度分析及密度与孔隙率分析等手段,对圆明园舍卫城城墙的夯土进行理化检测和工艺性能研究。结果表明:舍卫城城墙主要由石灰和土组成,且没有人为添加细砂,灰土比最接近二八灰土,与《工程做法则例》中的十六把小夯灰土相吻合。同时,通过多种科学数据对比,可进一步推测在夯筑灰土过程中,下层夯土使用了更多的灰土量。多层次的夯土制作工艺,展示了清代宫廷工匠对夯土技术的工艺认识和制作方法。相关结果为研究圆明园的建筑特点,夯土城墙的文物保护和科学修复等内容,提供了重要科学支持和有益借鉴。

In order to explore the rammed earth wall process of Sravasti of the Old Summer Palace,the physical and chemical testing and technological performance study of the rammed earth of the Sravasti wall of the Old Summer Palace were conducted using methods such as diffraction of X-rays(XRD) analysis,laser particle size analysis,and density and porosity analysis.The results show that the Sravasti loam wall is mainly composed of lime and soil,and there is no artificial sand added.The ratio of lime to soil is the closest to the two-eight,which is consistent with the sixteen small ash soils in the Engineering Practices.At the same time,through a variety of scientific data comparison,it can be further speculated that,during construction,the lower layer of rammed earth uses more amount of materials which are lime and soil.The multi-layer rammed earth manufacture demonstrates the craftsmanship and production methods in the Qing Dynasty on the rammed earth technology.For this unique site and special craft of lime and soil,the methods that combine literature and scientific data are used to restore its traditional processes.And the relevant results for the study can provide important scientific support and useful lessons for the protection and scientific restoration of the rammed earth walls.