St Marys Masonry Cement is a hydraulic cement produced specifically for use in mortar for unit masonry construction.

lntergrinding of portland cement clinker with plasticizers in the production of St Marys Masonry Cementp r ovides excellent plasticity, water retentivity and air-entrainment. An adequate level of air entrainmentenhances the important hardened property of mortar - durability, which is so important in the freeze-thawclimate of the Great Lakes region.

Masonry cement mortars may be specified by eitherthe proportion or property method of ASTM C270“Standard Specification for Mortar for UnitM a s o n r y”. Under Table 1 “Proportion SpecificationRe q u i r e m e n t s” (A), Type N mortar is specified as1 part Type N masonry cement to 2 1/4 to 3 partsaggregate (sand). Type S and M mortars arespecified the same way.

A l t e r n a t i ve l y, mortars may be specified byproperty requirements as in Table 2 (B), alaboratory prepared Type N mortar must meet7 50 psi in compressive strength to meet thestandard. Similarly Type S must meet 1800 psiand Type M must meet 2500 psi.

Appendix XI.1 of ASTM C270 provides a non-mandatory guide for the selection of masonrymortars for various locations and buildingsegments. Selection of mortar type should alsobe based on the type of masonry units to beused as well as the applicable building code andengineering practice standard requirements, suchas allowable design stresses and lateral support.

St Marys MasonryCements meets therequirements ofASTM Standard C91“S t a n d a r dSpecification forMasonry Cement.”

It also meets therequirements of thef o l l owing buildingcodes: AC I 5 30 . 9 5 ,IBC 2000, MBC2000 and MRC20 0 0 .

Mortar Type

Not less than 2 1/4 and notmore than 3 times the sum ofthe separate volumes ofcementitious materials.

ASTM C270 Table 1. Proportion Specification Requirements for Masonry Cement Mortars

Masonry Portland Cement Aggregate Ratio

Type Cement M S N (Measured in damp, loose, conditions)

M 1 1M 1S 1/2 1S 1N 1O 1

Note: Two air-entraining agents shall not be combined in mortar.

ASTM C270 Table 2. Property Specification Re q u i r e m e n t sa

for Masonry Cement Mortars

AverageCompressive

Strength Water Air Aggregate Ratioat 28 Days Retention Content (Measured in

Type Min. psi/MPa Min. % Max. % damp, loose, conditions)

M 2500 / 17.2 75 18S 1800 / 12.4 75 18N 750 / 5.2 75 20d

O 350 / 2.4 75 20d

a. Laboratory prepared mortar only.d. When the structural reinforcement is incorporated, the maximum air content

of Masonry Cement Mortar shall be 18%.

Not less than 2 1/4 and notmore than 3 1/2 times the sumof the separate volumes ofcementitious materials.

ASTM C270 (XI.1). Guide for the Selection of Masonry MortarBuilding

Location Segment Recommended Alternative

Exterior, load bearing wall N S or Mabove grade non-load bearing wall Ob N or S

parapet wall N SExterior, foundation wall, retaining S M or Nc

at or below grade wall, manholes, sewerspavements, walks & patios

Interior load bearing wall N S or Mnon-bearing partitions O N

b. Type O mortar recommended for use where the masonry is unlikely to be frozen when saturated or unlikely to be subjected to high winds or other significant lateral loads. Type N or S mortar should be used in other cases.

c. Masonry exposed to weather in a normally horizontal surface is extremely vulnerable to weathering. Mortar for such masonry should be selected with due caution.

Note: This table does not provide for many specialized mortar uses, such as chimneyreinforced masonry and acid-resistant mortars.

A

B

St Marys Mortar Cement is a higher bond strength and lower air content cement for use in mortar for unit masonry construction.

Mortar cement mortars may be specified by eitherthe proportion or property method of ASTM C270 .Under Table 1. (D), Type N mortar is specified as 1 part Type N mortar cement to 2 1/4 to 3 partsaggregate (sand). Type S is specified the same way.

A l t e r n a t i ve l y, mortars may be specified byproperty as in ASTM C270 Table 2 (E). To meetthe standard, a Type N laboratory prepared mortarmust meet 750 psi in compressive strength,similarly Type S mortar must meet 1800 psi.

Mortar cements were specifically developed toprovide comparable bond and compressivestrengths to portland cement/lime mortars, yetmaintain the excellent workability and durabilityof masonry cement mortars. St Marys MortarCements meet all requirements of ASTMC1329 Table 1 “Standard Specifications forMortar Cement” (C) and may be used in allseismic zones. Thus, St Marys Mortar Cementscan be specified for use in all masonryconstruction projects.

St Marys Mortar Cements meet therequirements of the following building codes:IBC 2000; MBC 2000 and UBC 21-14.

Air content and bond requirements outlined in ASTM C1329 must also be met. To evaluateour mortar cements for compliance, St MarysCement commissioned a number ofindependent laboratories whose test results are summarized in the table at right.

ASTM C1329 Table 1. P h ysical Requirements of Mortar Cement

Type Type TypeN S M

Flexural Bond Strength at 28 days, min. psi 70 100 115

Air Content of Mortar (Laboratory prepared)Min. % by volume 8 8 8Max. % by volume 17 15 15

Test Data of St Marys Mortar Cements relating to ASTM C1329 Table 1.Bond Strength

Air Content Min. Required ActualLaboratory Type Max.% Actual (psi) (psi)

St Marys Cement N 17 12.7 70 133W. R. Grace N 17 14.8 70 139Construction Technology N 17 13.1 70 107(S k o k i e, IL) MortarSt Marys Cement S 1 5 11 . 2 10 0 1 31W. R. Grace S 15 14.0 100 175R. L. Nelson & Ass. S 15 11.0 100 142(Schaumburg, IL)

ASTM C270 Table 1. Proportion Specifications for Mortar Cement Mortars

Mortar Aggregate RatioPortland Cement (Measured in damp,

Type Cement M S N loose, conditions)

M 1 1M 1S 1/2 1S 1N 1O 1

Mortar Cement conforming to the requirements of ASTM C1329.Note: Two air entraining agents shall not be combined in mortar.

Not less than 2 1/4 and notmore than 3 times the sum ofthe separate volumes ofcementitious materials.

ASTM C270 Table 2, Property Specification Re q u i r e m e n t sa

for Mortar Cement Mortars

AverageCompressive

Strength Water Air Aggregate Ratioat 28 Days Retention Content (Measured in

Type Min. psi/MPa Min. % Max. % damp, loose, conditions)

M 2500 / 17.2 75 12S 1800 / 12.4 75 12N 750 / 5.2 75 14c

O 350 / 2.4 75 14c

a. Laboratory prepared mortar only.c. When the structural reinforcement is incorporated, the maximum air content

of Masonry Cement Mortar shall be 12%.

Not less than 2 1/4 and notmore than 3 1/2 times the sum of the separate volumes of cementitious materials.

C

D

E