Study Of The Influence Analysis Of Foundation Excavation On Nearby Masonry Structure's Buildings And The Protection

Accompanied with quick development of the city modernization, Environment protection has become an important link to be considered in geotechnical engineering design and construction in cities. Now the deformation control has taken the place of the strength control to be the main standard. The differential settlement behind the retaining wall caused by the foundation excavation has great influence on the masonry structures. On the basis of intensive reading of domestic and foreign documents, the thesis analyzes the comprehensive influence of the foundation excavation to the adjacent building associating with the actual engineering on the Zhonghua new village of lane 447 Taixing road in shanghai and discusses how to establish statistical model by fitting the date of the settlement surveyed on the site and to forecast the future settlement of the buildings. Then we can adjust the construction craft and take the useful protections to the masonry structures. The studies mainly cover the following contents:1. From the aspects of foundation pit's reconnaissance, designing, construction, monitoring, the thesis analyzes the development and the present condition of the foundation pit, the characteristics of the foundation deformation and the theory of the deformation. The thesis still summarizes the ways of studying the foundation settlement behind the retaining wall during foundation excavation and gives some empirical estimate's formula.2. Reviewing the research results on the characteristics of the soft soil in shanghai, the different path of the strain during the foundation excavation, time-space effect in the foundation excavation, and the influence caused by the foundation excavation on ultimate bearing capacity, etc. the author Compares differential settlement caused by the self-weight and caused by the excavation and analyzes the cause of the differential settlement in the masonry structure and how to definite the damage standard of the bearing wall.3. Analyzes the stress level and deformation in the masonry structure caused bythe differential settlement of the foundation excavation by utilizing the deep beam model and the general effect of the shearing on the stress and deformation. When the depth is given, shearing effect in the bearing wall is more remarkable than the ulterior wall. When the same distance is give from the foundation pit, the deeper the foundation pit is, the more remarkable the effect of the shearing. The door and window in the bearing wall have more effect.4. According to investigation of main damage in Zhonghua new village, the author analyzes where will the main damage similar to Zhonghua new village masonry structures appear in the building and the characteristics of the damage under the normal designing, construction, monitoring. The deep beam model is proved to be practical in real engineering.5. Compares the difference between the Verhulst model and GM(1,1) model to analyze the data of the foundation settlement and analyze the precision of the model. With the information feedback we can adopt the appropriate protections.