A Study for Mix Proportion Analysis and Engineering Properties of Mortar

• Main Authors: Yan-Kai Yo, 游晏愷
• Other Authors: Der-Her Lee
• Format: Others
• Language: zh-TW
• Published: 2007
• Online Access: http://ndltd.ncl.edu.tw/handle/20690547123846385927

碩士 === 國立成功大學 === 土木工程學系碩博士班 === 95 === Abstract The mortar, consisting of the cementing material, lime, and various additives, is an important material in the construction of ancient architectures. The mixture proportion of the mortar traditionally dictated from craftsman to craftsman has failed to be handed down from the past generations. The preservation of the cultural heritage generally requires the use of the traditional mortar mixture to restore the ancient architectures. To this end, this study established a method for quantitatively analyzing the mortar mixture with the use of stereomicroscope micrograph analysis and the determination of content of the carbohydrate, calcium carbonate, and fine and coarse aggregates. Then, the method is employed to analyze the mortar mixture in the Remains Wall of the Fort Zeelandia, in the ruins of the Small East Gate section of Taiwan Fucheng, in the ruins of the Dongbianmen section of Fongshan City Wall, and in the ruins of the North Gate section of Hengchun City Wall. Due to the advantage of high strength and workability of the Portland cement, the traditional mortar is no longer used in the construction of recent architectures, which reflects the lack of studies of investigating the properties of the mortar. This study incorporates the basic physical property test, the carbonization rate test, the unconfined compressive and splitting tensile strength tests, the moisture content test, and the thermal conductivity test to investigate the physical and mechanical properties of the mortar. The test results include: (1) The mixture proportion of rendering and joint mortars in the Remains Wall of the Fort Zeelandia: Lime : Sand : Oyster Shell : Carbohydrate = 1.00 : 0.15 : 0.25 : 0.04 (2) The soil-lime mixture proportion in the ruins of the Small East Gate section of Taiwan Fucheng: Lime : Clay : Sand : Oyster Shell : Carbohydrate = 1.00 : 4.00 : 6.22 : 1.55 : 0.02 (3) With the use of lime, clay, Ly-port sand, and oyster shell, this study established an equation for evaluating the steady state strength of the mortar through the two parameters, the carbonization rates (x) and the strength increase rate (y) as follows: ( ) (4) The heat transfer coefficient of a pure lime sample with water/cement ratio of 0.75 is 0.42 , which is one third of that of the cement. In addition, the effect of use of the mortar on preventing the infiltration and evapotranspiration of the moisture is better than that of the Portland cement.