เทคนิคในการประมาณค่าการทรุดตัวของอาคารสูงในกรุงเทพมหานคร / ธานินทร์ พงศ์รุจิกร = Techniques in settlement prediction of highrise building in Bangkok Metropolis / Tanin Pongrujikorn
This thesis involves the settlement analyses of 6 highrise buildings from 5 construction sites in Bangkok. The analyses are carried out by using Terzaghi’s conventional method, Tomlison’s conventional method and modified theory of elasticity method proposed by Poulos and Davis. Analyses were made with made with the most reasonable soil informations and loading data, and results were compared with observation data. It was found that the settlement profile occurring in the whole building area formed generally the shallow bowl shape. The settlement rate observed during construction was rather slow in the first period and became faster in the latter. The settlement rate obviously depended upon the rate of loading and the magnitude of corrected observed total settlement was usually about 10 centimeters or more. The prediction of final settlement of the buildings by Terzaghi’s conventional method only gives the satisfactory results in certain buildings. Tomlinson’s conventional method yields better agreement with the measurement data, upon considering the soil stratum underneath the assumed equivalent flexible mat foundation as an average soil layer having the good drainage condition. The average settlement ratio, predicted total settlement/ recorded settlement, was about 1.2. Modified theory of elasticity method by Poulos and Davis can also give the good agreement having average settlement ratio of about 0.9, when the foundation was considered as the flexible mat foundation. It is discovered that relation exists among the observed settlement, the applied total vertical stress, the width of the building and the length of pile embedment in the stiff soil stratum.
