{"id":64697,"date":"2026-06-05T08:00:01","date_gmt":"2026-06-04T23:00:01","guid":{"rendered":"https:\/\/norimen.net\/?p=64697"},"modified":"2026-06-01T18:20:06","modified_gmt":"2026-06-01T09:20:06","slug":"mortar-spray-sand-1-24-m%c2%b3-bulk-absolute-volume","status":"publish","type":"post","link":"https:\/\/norimen.net\/en\/mortar-spray-sand-1-24m3-bulk-absolute-volume\/","title":{"rendered":"What Does 1.24 m\u00b3 of Sand for Sprayed Mortar Mean? | A Veteran Slope Engineer Thoroughly Explains Loose Volume and Absolute Volume"},"content":{"rendered":"

Hello, everyone.<\/p>\n

This is Enta.<\/p>\n

Every once in a while!<\/p>\n

I sometimes get asked, \u201cWhat does \u201d1.24 m\u00b3 of sand\u2019 mean in the mix design for sprayed mortar?\u201d<\/p>\n

Another reason is that lately, the specifications just say \u201csprayed mortar 1:4,\u201d and the figure of 1.24 m\u00b3 has been omitted lol.<\/p>\n

\"Mortar
Mortar Spraying Worker<\/figcaption><\/figure>\n

This time,The meaning of \u201c1.24 m\u00b3 of sand\u201d in the mix design for sprayed mortar<\/strong>,<\/p>\n

The Relationship Between Bulk Volume (Apparent Volume) and Absolute Volume (Volume of the Particles Alone)<\/strong>I'll start writing from there.<\/p>\n

Based on the test methods specified in JIS A 1104 and JIS A 1109, we will create a template that can be used for explanations.<\/p>\n

That said, I do feel that this way of thinking is a product of its time, so please keep this in mind if the topic ever comes up.<\/p>\n

What Does 1.24 m\u00b3 of Sand Mean? | Listed by Loose Volume<\/h2>\n

To put it simply,The entry \u201c1.24 m\u00b3 of sand\u201d in the mix design table represents the \u201cbulk volume\u201d when the sand is loaded onto a dump truck using a wheel loader (tire shovel).<\/strong><\/p>\n

The apparent volume, which includes not only the \"absolute volume\" consisting solely of densely packed grains of sand, but also the air gaps between the grains<\/strong>That's it.<\/p>\n

In the old standard specifications, the mix design for sprayed mortar (volume ratio 1:4) was stated as follows:<\/p>\n\n\n\n\n\n\n
Ingredients<\/th>\nMass<\/th>\nVolume (bulk volume)<\/th>\n<\/tr>\n<\/thead>\n
Cement<\/td>\n420 kg<\/td>\n\u2014<\/td>\n<\/tr>\n
\u7802<\/td>\n1,680 kg<\/strong><\/td>\n1.24 m\u00b3<\/strong><\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n

*Example mix ratios for on-site formwork and mortar spraying per 1 m\u00b3 of mortar.
\nTraditional cost estimation standards and standard specifications documents from various organizations<\/p>\n

The Relationship Between 1.24 m\u00b3 and 1,680 kg<\/h3>\n

These figures are derived from simple proportional calculations. For general-purpose fine aggregate (sand),Mass per unit volume in loose state (uncompacted)<\/strong>is approximately 1.35 t\/m\u00b3 (measured in accordance with JIS A 1104, \u201cTest Methods for Unit Volume Mass and Bulk Density of Aggregates\u201d).<\/p>\n

1.24 m\u00b3 \u00d7 1.35 t\/m\u00b3 \u2248 1.67 t (= 1,670 kg) \u2248 1,680 kg<\/strong><\/p>\n

In other words, it\u2019s a simple relationship between volume and mass per unit volume: \u201c1.24 m\u00b3 of loose sand contains approximately 1,680 kg of sand.\u201d<\/p>\n

These vary slightly depending on the sand's specific gravity, source, and moisture content.<\/strong>Therefore, when calculating the exact mix design, it is standard practice to measure the bulk density of the on-site sand.<\/p>\n

\"Conceptual<\/p>\n

Reasons for Distinguishing Between Apparent Volume and Absolute Volume<\/h2>\n

In the world of formulation calculations,It is very important to distinguish between \u201capparent volume\u201d and \u201cabsolute volume.\u201d<\/strong>That's it.<\/p>\n