The injection grout (type CPA-CEM I), after initial setting, has a shear threshold of 4 Pa or more, and initial viscosity of 0.3 Pa.s, all testing being at 20 deg C, in accordance with Fann methodology. No traces of exudation are visible, following a 24 hour, inclined-tube test (see figure). Independent claims are included. These cover: a kit based on the materials described, used to make up the grout; a civil engineering structure including prestressing cables in such grouting; and the method of quality verification by Fann testing and measurements as prescribed. Uses are also claimed (see appropriate heading). Preferred features: A Portland cement base is used, the cement having a specific area of 3000-3200 cm2/gm. The sulfate content is 1.5-2.5 wt %. E/C ratio is 0.32-0.38. The (super) plasticizer amounts to 0.5-1.5 wt %, based on dry weight, in relation to the total weight of cement present. Further percentages of plasticizer and viscosity modification agents are quantified in accordance with type. Quantified formulations based on the foregoing principles are also provided.
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