Publication Abstract

Proceedings - Fourth International Conference - Piling and Deep Foundations, 1991, Stresa, Italy, (DFI)

A Monitoring System for the Quality Assessment of the Jet Grouting Process Through an Energy Approach
B. De Paoli, C. Stella & A. Perelli Cippo; RODIO SpA, Casalmaiocco, Milan, Italy L. Locatelli; GEOCAD Srl, Milan, Italy

Soil improvement by jet grouting technique is employed in a wide range of projects, such as underpinning, tunneling, cut-off-walls and shafts excavation. In the last few years jet grouting proved reliable and effective in so many circumstances that it is ever more frequently applied when critical situations are foreseen, especially in the urban areas. The extensive use of this technique led to the necessity of electronic monitoring of the jet grouting industrial process. This to enable real time quality control and immediate availability of data in order to support the operational choices and the engineering analyses. The paper deals with the electronic monitoring system PAPERJET, recently developed by RODIO, and the results of some field experiences. The energetic approach, inherent to the measured parameters, based on instrumented drilling and instrumented high pressure grouting results, is applied both to determine soil profile along the axis of the columns and to evaluate the energy spent for their construction. The PAPERJET System allows real time monitoring of jet grouting parameters by visual display under graphical and numerical representation form, data recording and automatic storage and printing in real time of all the data acquired. The whole system is installed on the rig and consists of sensors, data acquisition unit, portable computer and dedicated software. The data acquired by PAPERJET System, besides allowing a comprehensive control of the process, makes it possible to carry out an effective economical evaluation of the results obtainable, comparing the energy spent during grouting and drilling phases.

 article #472; publication #37 (IC-1991-IT)