The Contribution of Glass Microspheres and PP Fibers in the Properties of NHL Grouts

Research output: Contribution to journalConference articlepeer-review


Although, over the last decades, different types of additions have been used in mortars for conservation of heritage buildings, their use in lime-based grouts for stone masonry consolidation is limited. The purpose of this study is to contribute to the increase of knowledge regarding the performance of injection grouts prepared with glass microspheres and polypropylene (PP) fibers. The effects of glass microspheres and PP fibers on the properties of natural hydraulic lime-based grouts were analysed by rheological measurements, mechanical strength tests, water absorption and drying test. The content of glass microspheres (5-20%) and PP fiber (0.1-0.5%) was added by the weight of binder and to reduce the water demand, a polycarboxylate superplasticizer was used. From the assessment of the results, it was asserted that the fresh state behaviour was slightly affected by these additions, as in general the rheological properties worsened compared to the reference grout composition. On the other hand, the PP fibers influenced the hardened grouts’ properties in a positive way, while their mechanical and physical properties were slightly improved or maintained which is a crucial feature for the success of consolidation intervention
Original languageEnglish
Pages (from-to)491-497
Number of pages7
JournalKey Engineering Materials
Publication statusPublished - Apr 2022


Dive into the research topics of 'The Contribution of Glass Microspheres and PP Fibers in the Properties of NHL Grouts'. Together they form a unique fingerprint.

Cite this