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The MRT Orange Line construction works in Bangkok are more complicated than works in earlier projects. As the tunnel alignment passes through the congested urban areas in the city, it either clashes with or passes beneath several existing structures. Underpinning works are then required. Assessment of movement of ground and structure plays an important role in the project. The rebound of piezometric pressure in sand layers that is being developed poses a major point of difficulty in the excavation and underground structure design and construction. Groundwater control measures become a crucial issue in MRT Orange Line project that leads to difficulties in deep MRT station excavations. To control base instability, various methods (e.g., cut‐off wall, staged excavation) are introduced and presented in this article. [ABSTRACT FROM AUTHOR]

A building and its foundation were constructed in sandy ground using a reverse construction method. The main difference between a reverse construction method and a conventional construction method is that the piles are cast in place and are partially loaded by the superstructure early during the construction process. It is only later that the raft (mat foundation) is constructed to combine with the piles to bear the full building load. Therefore, the foundation is regarded as a pile group in early stages of construction, while the foundation behaves as a piled raft after completion of the raft construction. A simple conservative design approach was used for the design of the foundation. To examine the validity of the design method, settlements of the foundation were observed during construction. The measured settlements were smaller than those predicted in the design stage, satisfying the design requirements for the building. Post-analysis of the deformation of the foundation was carried out using the results of the pile load test at the construction site, and the results of the analysis are compared with the observed settlements of the foundation, aiming at an improvement in pile foundation design. Un bâtiment et ses fondations ont été construits sur un sol sablonneux selon la méthode de construction inverse. La différence principale entre la méthode de construction inverse et la méthode de construction traditionnelle est que les pieux sont installés et partiellement chargés par la superstructure au début de la construction. Ce n’est que plus tard que le radier (tapis de fondation) est construit et combiné aux pieux pour soutenir toute la charge du bâtiment. Ainsi, la fondation est considérée comme un groupe de pieux au début de la construction, alors que la fondation se comporte plutôt comme un radier sur pieux une fois le radier construit. Une approche simple et conservatrice a été utilisée pour la conception de la fondation. Afin d’évaluer la validité de la méthode de conception, le tassement des fondations a été observée durant la période de construction. Les tassements mesurés étaient plus faibles que ceux prédits à l’étape de conception, ce qui correspond aux exigences de construction du bâtiment. Une analyse de la déformation des fondations a été effectuée à partir de résultats d’essais de chargement sur les pieux au site de construction; les résultats de cette analyse ont été comparés avec les résultats d’observations de tassement des fondations, ceci dans le but d’améliorer la conception de fondations sur pieux. [ABSTRACT FROM AUTHOR]