Sökning: "Chadi El Mohtar"

Hittade 2 avhandlingar innehållade orden Chadi El Mohtar.

  1. 1. An Experimental Study to Measure Grout Penetrability, Improve the Grout Spread, and Evaluate the Real Time Grouting Control Theory

    Författare :Ali Nejad Ghafar; Stefan Larsson; Almir Draganovic; Chadi El Mohtar; KTH; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Byggvetenskap; Civil and Architectural Engineering;

    Sammanfattning : Due to the significant influence of the grout penetrability properties on spread of grout in rock fractures, this study aimed to investigate the grout penetrability from four different aspects. In Part (a), after review of all the existing methodologies developed to measure the grout penetrability, Filter-pump and Penetrability-meter were examined against Short-slot to figure out which one is more reliable. LÄS MER

  3. 2. Rock grouting design: Rheological aspects and radial flow visualizations with ultrasound

    Författare :John Shamu; Stefan Larsson; Ulf Håkansson; Liangchao Zou; Chadi El Mohtar; KTH; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Cement grouts; grouting; yield stress fluid YSF ; thixotropy; critical shear rate; radial flow; wall slip; Bingham model; Cementbaserade injekteringsmedels; injektering; icke-Newtonska vätskors; tixotropi; kritisk deformationshastigheten; radiella strömning; glidning; Bingham modell; Jord- och bergmekanik; Soil and Rock Mechanics;

    Sammanfattning : The rheological properties of cement-based grouts play a crucial role indetermining the final spread in grouted rock formations. In rheological terms,cement grouts are known to be complex time-dependent yield stress fluids,but their steady flow behavior is often described by the simple Binghamconstitutive law. LÄS MER