Influence of superplasticizer, temperature, resting time and injection pressure on hydraulic lime grout injectability. Correlation analysis between fresh grout parameters and grout injectability

Combination of Polymeric Superplasticizers, Water Repellents and Pozzolanic Agents to Improve Air Lime-Based Grouts for Historic Masonry Repair

“…This fact seems to be of the utmost importance for the two superplasticizers whose action mechanism is mainly based on electrostatic repulsions (PNS and SMFC). The dosage of 1% (O-SMFC1 and O-PNS1) showed very similar values to those published by other authors (which were between 0.016 and 0.038 s −1 ) [1,6,12,44].…”

“…Samples with pozzolanic additions yielded higher bleeding values, although all of them were below the limit value. Accordingly, the designed grouts do not present excess of free water and can be considered as stable [12]. PCE as admixture with pozzolanic materials presented the lowest bleeding percentages, except for samples with microsilica.…”

Evaluation of the grout injectability and types of resistance to grout flow

“…The formulation of the grout was chosen based on the guidelines and recommendations of the several authors [12,[22][23][24] and used a HL5 hydraulic lime (EN459-1) produced in Portugal by Secil-Martingança. The water/binder ratio (w/b) was 50% in weight with 1.2 wt% of superplasticizer (polycarboxilate Glenium SKY 617 produced by BASF).…”

“…The grout composition was chosen based on the results of some tests, namely: fluidity, water retention, stability and injectability. This study was carried out in another article of the authors [23,24].…”

“…For the preparation of grouts water at the temperatures of 18 ± 1°C was used and the dry hydraulic lime was hand-mixed to ensure a homogeneous distribution before the beginning of the mechanic mixing. The mixing procedure was chosen in accordance with previous research of the team [23,25].…”