Eine Plattform für die Wissenschaft: Bauingenieurwesen, Architektur und Urbanistik
Eine Plattform für die Wissenschaft: Bauingenieurwesen, Architektur und Urbanistik
Verification of Foundation Improvement Using Low Mobility Grouting
Low mobility grouting (LMG) was used to improve the condition of limestone bedrock to support the foundations of a single span bridge in Northampton County, Pennsylvania. Test borings showed the presence to extensive solution activity in the upper rock strata, which was found not suitable for foundation support without improvement. After alternative analysis, it was determined that the preferred foundation system is the improvement of the upper rock strata using LMG. The LMG treatment area was selected as the footprint of the foundation, plus an “allowance” for effective distribution of bearing stresses into the deeper rock mass. Primary and secondary injections were spaced in grid pattern and supplementary injections were added in areas where the distance to the nearest grout hole was excessive. A total of 271 holes were proposed with a design treatment depth of 4.5 m below proposed bottom of footing (BFE). Four verification borings were drilled, two at each abutment, after completion of the 271 injections. Six additional injections were added based on the result of the original injections and the verification borings. The LMG program was designed to achieve a target rock recovery required for foundation support for this bridge. The paper summarizes the construction aspect of spread footing on bedrock improved by LMG in karst and verification of bearing improvement after the LMG. The paper discusses related aspects of the project, including the subsurface conditions, LMG design, and other challenges that were specific to this project. The paper will document how the design was actually implemented and verified, plus the adjustments that were needed to in the field to achieve the goal. This project showed that LMG can be successfully used in karst with proper inspection and on-site adjustment to address variation of subsurface conditions.
Verification of Foundation Improvement Using Low Mobility Grouting
Low mobility grouting (LMG) was used to improve the condition of limestone bedrock to support the foundations of a single span bridge in Northampton County, Pennsylvania. Test borings showed the presence to extensive solution activity in the upper rock strata, which was found not suitable for foundation support without improvement. After alternative analysis, it was determined that the preferred foundation system is the improvement of the upper rock strata using LMG. The LMG treatment area was selected as the footprint of the foundation, plus an “allowance” for effective distribution of bearing stresses into the deeper rock mass. Primary and secondary injections were spaced in grid pattern and supplementary injections were added in areas where the distance to the nearest grout hole was excessive. A total of 271 holes were proposed with a design treatment depth of 4.5 m below proposed bottom of footing (BFE). Four verification borings were drilled, two at each abutment, after completion of the 271 injections. Six additional injections were added based on the result of the original injections and the verification borings. The LMG program was designed to achieve a target rock recovery required for foundation support for this bridge. The paper summarizes the construction aspect of spread footing on bedrock improved by LMG in karst and verification of bearing improvement after the LMG. The paper discusses related aspects of the project, including the subsurface conditions, LMG design, and other challenges that were specific to this project. The paper will document how the design was actually implemented and verified, plus the adjustments that were needed to in the field to achieve the goal. This project showed that LMG can be successfully used in karst with proper inspection and on-site adjustment to address variation of subsurface conditions.
Verification of Foundation Improvement Using Low Mobility Grouting
Haider, Tarek F. (Autor:in) / Morgan, Christopher J. (Autor:in) / Poudyal, Roman (Autor:in)
Geo-Congress 2020 ; 2020 ; Minneapolis, Minnesota
Geo-Congress 2020 ; 705-715
21.02.2020
Aufsatz (Konferenz)
Elektronische Ressource
Englisch
Verification of Foundation Improvement Using Low Mobility Grouting
| British Library Conference Proceedings | 2020
Limited Mobility Displacement Grouting Design for Foundation Bearing Improvement
| British Library Conference Proceedings | 2012
Grouting for Pile Foundation Improvement
| NTIS | 2001