Mucheti, Alexsander Silva (2025) Experimental and numerical analysis of nailed soil structures in urban areas. PhD thesis, Universidade Estadual de Campinas, Brazil.
Abstract
In this research, the behavior of 21 vertical face soil nailing structures in urban areas intended for building basements was analyzed. The projects were carried out in the metropolitan region of São Paulo. The excavation heights ranged from 6.8 to 22.7 meters, with controlled measurements of the face displacements from the start to the end of construction. Given the low magnitude of the displacements, two factors influencing behavior and performance were evaluated. The first factor pertains to the influence of execution speed on displacements. For 15 projects, the execution time was analyzed with a focus on the progression of excavation lines at intervals of 3, 4, and 5 days, as well as on the productive index of the work in m²/day. The second factor evaluated was the influence of sectorized post grouting injections, which significantly increase the soil's stiffness. Three-dimensional computational models were developed, analyzed, and calibrated using the PLAXIS 3D software, examining variations in nail length, vertical and horizontal spacing (mesh), and soil strenght and deformability parameters within a standard design and execution practice adopted in Brazil and based on the displacements observed in the projects. Equations are proposed for estimating horizontal displacements involving the aforementioned factors. The results indicated a significant reduction in displacements compared to estimates from the literature referring to projects conducted more than 30 years ago.
| Item Type: | Thesis (Doctoral) |
|---|---|
| Uncontrolled Keywords: | experimental learning; finite element method; geosynthetics; numerical analysis |
| Index terms: | injection, estimating, excavation, urban area, variation, numerical analysis, face, Brazil, computational model, grouting, estimate, finite element method |
| Subjects: | manufacturing engineering, urban form and morphology, Geography, engineering analysis, psychology, construction methods, construction operations, contractual condition, modelling and simulation, data analysis and analytics, financial and cost management |
| Topics: | Design Practice, Digital Applications, Urban Studies, Contract Administration, Organizational Design, Site Management, Cost Management, Research Practice, Geographical Context, Engineering Principles |
| Descriptive scope: | 3 PCA |
N.B. Descriptive scope is a count of how many of the five facets of empirical research are indicated by the words used in title, abstract and keywords. It is not intended as a judgement on the research; merely a count of the kind of word we would expect to indicate Phenomenon, Concepts, Theoretical framing, Empirical techniques, Analytical techniques. If all five are present, then a code of “5 PCTEA” will indicate this. If you feel the coding for this record is questionable, we welcome discussion around the terms we matched or the way we categorized them. The facet you would expect may not be coded, or a facet may be coded inappropriately. This can also bear on a larger question, of which facets should be treated as defining in construction management research. Please get in touch, and we will look at it. More details here