New Mexico Administrative Code › Title 14 - HOUSING AND CONSTRUCTION › Chapter 7 - BUILDING CODES GENERAL › Part 4 - 2021 NEW MEXICO EARTHEN BUILDING MATERIALS CODE › Section 14.7.4.14 - RAMMED EARTH SOIL SPECIFICATIONS

Current through Register Vol. 35, No. 13, July 16, 2024
A.
General.
The soil shall not contain rock more than one and
				one-half inch in diameter. The soil shall not contain clay lumps more than
				one-half inch in diameter. The soil shall be free of all organic matter. The
				soil shall not contain more than two percent soluble salts.
B.
Soil compressive strength.
Prior to the start of construction, fully-cured rammed earth soil samples shall
				be tested at an approved testing laboratory for compressive strength. The
				ultimate compressive strength of all rammed earth soil, stabilized or
				non-stabilized, shall be a minimum 300 psi. The compressive strength report
				shall be submitted with the permit application. This report may be waived if
				the builder provides certification of compliance. The certification must be
				dated within one year of the date on the application for the building permit.
				Samples tested shall be representative of soil to be used on the project for
				which the permit application is submitted.
C.
Stabilized rammed earth soil.
The following shall apply to stabilization of rammed earth soil: Asphalt
				emulsion may not be used for stabilization of rammed earth soil. Thorough
				mixing of additives to the soil may be achieved by any method that assures a
				complete blending to a uniform color and texture. Stabilized soil is suitable
				soil that contains six percent or more Portland cement by weight or that passes
				ASTM D1633-00. Samples tested shall be representative of soil to be used on the
				project for which the permit application is submitted. The compressive strength
				report shall be submitted with the permit application. Laboratory testing shall
				indicate rammed earth samples attained a minimum of 200 psi after seven days.
				If a different soil is provided at any time during construction, it must meet
				the minimum requirements outlined above, prior to use in the
				structure.
D.
Unstabilized
				rammed earth soil.
Unstabilized rammed earth soil is that containing
				less than six percent Portland cement by weight or that fails to pass ASTM
				D1633-00. The exterior of such walls shall be protected with approved stucco
				systems or other method approved by the building official. Refer to
				14.7.4.19
				NMAC for weather-resistive barrier requirements.
E.
Amended soil.
The following
				guidelines shall apply when amending soils to attain a qualified soil. Soil
				shall not contain rock greater than one and one-half inch in diameter. Soil
				shall not contain clay lumps greater than one-half inch diameter. Soil shall be
				free of organic matter. Soil shall not contain more than two percent soluble
				salts. Soils to be mixed shall be sufficiently dry to blend completely to one
				uniform color and texture. The amended soil shall be tested prior to use as per
				Subsection B of 14.7.4.14 NMAC.
F.
Forming systems.
The forming system shall be adequate to contain
				the material under compaction. It shall be properly plumbed and braced to
				withstand the soil pressures as well as construction activity on and around
				it.
G.
Placement of material,
				compaction and curing.
(1) No amount of
				Portland cement stabilized soil will be mixed that will not be placed in the
				wall system within 60 minutes of its preparation.
(2) Lifts of prepared soil shall be placed in
				the forms in relatively even layers not to exceed eight inches in depth. Each
				lift shall then be rammed to full compaction.
(3) Optimum moisture content as determined to
				meet minimum compressive strength shall be maintained for stabilized and
				unstabilized walls.
(4) Work will
				progress, lift-by-lift, until the work approaches bond beam height.
(5) Forms may be stripped immediately after
				ramming is completed for a section of wall, providing ramming of adjacent
				sections does not affect the structural integrity of completed walls.
(6) Portland cement stabilized walls not in
				forms shall be lightly spray-cured with water at least five spaced times during
				daylight hours. This procedure shall continue for at least three days starting
				from the time that the wall is exposed to the elements. Exception: Rammed earth
				walls left in forms three or more days shall not require water-spray
				curing.