Investigations on Flexural and Compressive Strengths of Mortar Dedicated to Clinker Units—Influence of Mixing Water Content and Curing Time

Abstract

The article presents laboratory tests on the impact of the mixing water content used in the preparation of fresh mortar on the flexural and compressive strength of one of the dry-mix mortars produced by a leading European producer and dedicated to bricklaying with clinker elements. The development of these parameters in relation to curing time was also analyzed. The mortar samples were prepared from a factory-made mortar mix using 4.0 L (the value recommended by the mortar manufacturer), 4.5 L, and 5 L of water per 25 kg bag of ready-made, pre-mixed dry mortar mix. All samples were tested in five series after 5, 9, 14, 21, and 28 days of sample curing. The results of these tests showed that the use of 6 and 18% more mixing water than recommended by the manufacturer (4.5 and 5 L per bag) adversely affected the basic mechanical parameters of the tested mortar. Moreover, it was found that the highest compressive strength values were obtained after 21 days of curing and not after 28 days as usual. It was also found that hardening time and higher than recommended water content adversely affected the bending strength of the mortar.

Influence of Mixing Water Content and Curing Time on Bond Strength of Clinker Masonry: The Wrench Test Method

“…Of course, as is well known, a great many factors affect the values of bond strength [ 33 , 52 , 59 ], including mortar physic-mechanical parameters [ 7 , 53 , 56 , 60 , 61 ]. In the processes presented and analyzed below, the value of IRA is, of course, very important, but so is the connection with the porosity of masonry elements (number of open pores and total number of pores) and the size and number of capillaries [ 62 ], also in relation to mortar, which is equally important [ 50 ].…”

“…In addition, analysis of the properties of mortar itself (compressive strength and flexural strength) presented in Table 2 [ 59 ] shows that the 28-day parameters are significantly lower than the parameters after 14 and 21 days of curing time. This phenomenon can be explained, at least in part, from the point of view of the interaction of masonry units and mortar.…”

“…Tests on the mechanical properties of mortar were carried out in accordance with EN 1015-11:1999 [ 58 ]. The authors presented the exact results of these tests in [ 59 ]. The analyzed factors affecting the mechanical parameters of mortar were as follows: amount of mixing water—4 L, 4.5 L, and 5 L were adopted; curing time—five periods were assumed, namely 5 days, 9 days, 14 days, 21 days, and 28 days.…”

“…In [ 59 ], the values of flexural strength and compressive strength were determined and analyzed for each of the above-mentioned amounts of mixing water and each curing time. Below, Table 1 summarizes the obtained average values of these two strengths.…”

Maximizing Volume of Spent Bleaching Earth Ash (Sbea) Pozzolan Used as Cement Replacement in Mortar Through Mechanical Activation

“…These comparisons were carried out using the ratio of flexural strength/ compressive strength (fcuf/fcu). The theoretical flexural strengths were obtained from various such as (Kubica & Galman, 2022) The comparison is presented in Figure 19.…”