Strength and permeability of boric acid-tempered ultrafine cement grouted sand: Fid-Bau Portal

Strength and permeability of boric acid-tempered ultrafine cement grouted sand

Mollamahmutoglu, Murat / Avci, Eyubhan

Highlights • The groutability of Ufc grouts was bettered and increased with the addition of Boric acid. • The Ucs of Ufc grouted sands were decreased with Boric acid additive. • The boric acid additive reduced the permeabilities of Ufc grouted sands. • Both the permeability and Ucs of boric acid amended Ufc grouted sand specimens were found to be time-dependent.

Abstract In this research, the groutabiliy of ultrafine cement (Ufc) grouts containing an additive of boric acid (BA) into the sand specimens with different particle size distribution and the engineering properties of grouted specimens were investigated. To begin with, the rheological characteristics of the neat UFC grouts having w/c ratios of 0.8, 1.0, 1.2, and 1.5 and those with 0.25, 0.50, 0.75, 1.0, 2.0, 3.0 contents of BA additive were determined. Later on, the groutability of various graded sand specimens were tested with the neat UFC and BA mixed grouts. Finally, the time-dependent strength and permeability tests were conducted on the successfully grouted sand specimen. With the addition of BA to UFC grouts, their setting times were extended but their viscosities, as well as their bleedings, were reduced. The groutability of UFC grouts was bettered with the addition of BA and the grouting pressure for the sand specimens was therefore reduced. The unconfined compressive strength (UCS) and the permeability of UFC grouted sand specimens were decreased with BA additive.