ASTM C270 - 25b 砌块砌体用砂浆的标准规范

VIP免费

标准小能手 2026-08-31 8 269.56KB 14 页 24星币

Designation: C270 −25b
Standard Speciﬁcation for
Mortar for Unit Masonry
1
This standard is issued under the ﬁxed designation C270; the number immediately following the designation indicates the year of
original adoption or, in the case of revision, the year of last revision. A number in parentheses indicates the year of last reapproval. A
superscript epsilon (´) indicates an editorial change since the last revision or reapproval.
This standard has been approved for use by agencies of the U.S. Department of Defense.
1. Scope*
1.1 This speciﬁcation covers mortars for use in the construc-
tion of non-reinforced and reinforced unit masonry structures.
Four types of mortar are covered in each of two alternative
speciﬁcations: (1) Proportion Speciﬁcation and (2) Property
Speciﬁcation.
NOTE 1—When the Property Speciﬁcation is used to qualify masonry
mortars, the testing agency performing the test methods should be
evaluated in accordance with Practice C1093.
1.2 The Proportion Speciﬁcation or Property Speciﬁcation
shall govern as speciﬁed.
1.3 When neither the Proportion Speciﬁcation or the Prop-
erty Speciﬁcation are speciﬁed, the Proportion Speciﬁcation
shall govern, unless data are presented to and accepted by the
speciﬁer to show that mortar meets the requirements of the
Property Speciﬁcation.
1.4 This standard is not a speciﬁcation to determine mortar
strengths through ﬁeld testing (see Section 3).
1.5 The text of this speciﬁcation references notes and
footnotes which provide explanatory material. These notes and
footnotes (excluding those in tables and ﬁgures) shall not be
considered as requirements of the standard.
1.6 The terms used in this speciﬁcation are identiﬁed in
Terminologies C1180 and C1232.
1.7 The values stated in inch-pound units are to be regarded
as standard. The values given in parentheses are mathematical
conversions to SI units that are provided for information only
and are not considered standard.
1.8 The following safety hazards caveat pertains only to the
test methods section of this speciﬁcation: This standard does
not purport to address all of the safety concerns, if any,
associated with its use. It is the responsibility of the user of this
standard to establish appropriate safety, health, and environ-
mental practices and determine the applicability of regulatory
limitations prior to use.
1.9 This international standard was developed in accor-
dance with internationally recognized principles on standard-
ization established in the Decision on Principles for the
Development of International Standards, Guides and Recom-
mendations issued by the World Trade Organization Technical
Barriers to Trade (TBT) Committee.
2. Referenced Documents
2.1 ASTM Standards:
2
C5 Speciﬁcation for Quicklime for Structural Purposes
C33/C33M Speciﬁcation for Concrete Aggregates
C67/C67M Test Methods for Sampling and Testing Brick
and Structural Clay Tile
C91/C91M Speciﬁcation for Masonry Cement
C109/C109M Test Method for Compressive Strength of
Hydraulic Cement Mortars (Using 50 mm [2 in.] Cube
Specimens)
C110 Test Methods for Physical Testing of Quicklime,
Hydrated Lime, and Limestone
C128 Test Method for Relative Density (Speciﬁc Gravity)
and Absorption of Fine Aggregate
C144 Speciﬁcation for Aggregate for Masonry Mortar
C150/C150M Speciﬁcation for Portland Cement
C188 Test Method for Density of Hydraulic Cement
C207 Speciﬁcation for Hydrated Lime for Masonry Pur-
poses
C305 Practice for Mechanical Mixing of Hydraulic Cement
Pastes and Mortars of Plastic Consistency
C511 Speciﬁcation for Mixing Rooms, Moist Cabinets,
Moist Rooms, and Water Storage Tanks Used in the
Testing of Hydraulic Cements and Concretes
C595/C595M Speciﬁcation for Blended Hydraulic Cements
C780 Test Methods for Preconstruction and Construction
Evaluation of Mortars for Plain and Reinforced Unit
Masonry
1
This speciﬁcation is under the jurisdiction of ASTM Committee C15 on
Masonry - Manufactured Masonry Units, Mortars and Groutsand is the direct
responsibility of Subcommittee C15.30 on Speciﬁcations for Mortars and Grouts.
Current edition approved Dec. 1, 2025. Published January 2026. Originally
approved in 1951. Last previous edition approved in 2025 as C270 – 25a. DOI:
10.1520/C0270-25B.
2
For referenced ASTM standards, visit the ASTM website, www.astm.org, or
contact ASTM Customer Service at www.astm.org/contact. For Annual Book of
ASTM Standards volume information, refer to the standard’s Document Summary
page on the ASTM website.
*A Summary of Changes section appears at the end of this standard
Copyright © ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States
This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the
Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.
1

C952 Test Method for Bond Strength of Mortar to Masonry
Units (Withdrawn 2017)
3
C979/C979M Speciﬁcation for Pigments for Integrally Col-
ored Concrete
C1072 Test Methods for Measurement of Masonry Flexural
Bond Strength
C1093 Practice for Accreditation of Testing Agencies for
Masonry
C1157/C1157M Performance Speciﬁcation for Hydraulic
Cement
C1180 Terminology of Mortar and Grout for Unit Masonry
(Withdrawn 2025)
3
C1232 Terminology for Masonry
C1324 Test Method for Examination and Analysis of Hard-
ened Masonry Mortar
C1329/C1329M Speciﬁcation for Mortar Cement
C1384 Speciﬁcation for Admixtures for Masonry Mortars
C1489 Speciﬁcation for Lime Putty for Structural Purposes
C1506 Test Method for Water Retention of Hydraulic
Cement-Based Mortars and Plasters
C1586 Guide for Quality Assurance of Mortars
C1602/C1602M Speciﬁcation for Mixing Water Used in the
Production of Hydraulic Cement Concrete
C1713 Speciﬁcation for Mortars for the Repair of Historic
Masonry
C1714/C1714M Speciﬁcation for Preblended Dry Mortar
Mix for Unit Masonry
C1717 Test Methods for Conducting Strength Tests of Ma-
sonry Wall Panels
E514/E514M Test Method for Water Penetration and Leak-
age Through Masonry
E518/E518M Test Methods for Flexural Bond Strength of
Masonry
2.2 The Masonry Society:
4
TMS 602 Speciﬁcations for Masonry Structures
3. Speciﬁcation Limitations
3.1 Laboratory testing of mortar to ensure compliance with
the Proportion Speciﬁcation requirements of this speciﬁcation
shall be performed in accordance with 5.3. The Property
Speciﬁcation of this standard applies to mortar mixed to a
speciﬁc ﬂow in the laboratory.
3.2 Property speciﬁcation requirements in Table 1 shall not
be used to evaluate construction site-produced mortars.
NOTE 2—Refer to X5.2 for further explanation.
3.3 Since the compressive strength values resulting from
ﬁeld tested mortars do not represent the compressive strength
of mortar as tested in the laboratory nor that of the mortar in the
wall, physical properties of ﬁeld sampled mortar shall not be
used to determine compliance to this speciﬁcation and are not
intended as criteria to determine the acceptance or rejection of
the mortar (see Section 8and Guide C1586).
4. Materials
4.1 Materials used as ingredients in the mortar shall con-
form to the requirements speciﬁed in 4.1.1 to 4.1.4.
4.1.1 Cementitious Materials—Cementitious materials shall
conform to the following ASTM speciﬁcations:
4.1.1.1 Portland Cement—Types I, IA, II, IIA, III, IIIA, or
V of Speciﬁcation C150/C150M.
4.1.1.2 Blended Hydraulic Cements—Types IL, IL-A, IS,
IS-A, IP, IP-A, IT, and IT-A of Speciﬁcation C595/C595M.
Blended hydraulic cements with 70 % or more slag cement
content are only permitted for use in Property Speciﬁcation.
3
The last approved version of this historical standard is referenced on
www.astm.org.
4
Available from The Masonry Society (TMS), 105 South Sunset Street, Suite Q,
Longmont, CO 80501, http://www.masonrysociety.org.
TABLE 1 Property Speciﬁcation Requirements
A
Mortar Type Average Compressive
Strength at 28 days, min,
psi (MPa)
Water Retention, min, % Air Content, max, %
B
Aggregate Ratio
(Measured in Damp,
Loose Conditions)
Cement-Lime
C
M 2500 (17.2) 75 12
S 1800 (12.4) 75 12
N 750 (5.2) 75 14
D
O 350 (2.4) 75 14
D
Mortar Cement M 2500 (17.2) 75 18 Not less than 2
1
⁄
4
and not
more than 3
1
⁄
2
times the
sum of the separate
volumes of cementitious
materials
S 1800 (12.4) 75 18
N 750 (5.2) 75 20
E
O 350 (2.4) 75 20
E
Masonry Cement M 2500 (17.2) 75 18
S 1800 (12.4) 75 18
N 750 (5.2) 75 20
E
O 350 (2.4) 75 20
E
A
Laboratory prepared mortar only (see Note 5).
B
See Note 6.
C
Includes Speciﬁcation C150/C150M,C595/C595M, and C1157/C1157M cements as described in 4.1.1.
D
When structural reinforcement is incorporated in cement-lime, the maximum air content shall be 12 %.
E
When structural reinforcement is incorporated in masonry cement mortar or mortar cement mortar, the maximum air content shall be 18 %.
C270 − 25b
2

4.1.1.3 Hydraulic Cements—Types GU, HE, MS, and HS of
Speciﬁcation C1157/C1157M. Types MH and LH are only
permitted for use in Property Speciﬁcation.
4.1.1.4 Masonry Cement—Speciﬁcation C91/C91M.
4.1.1.5 Mortar Cement—Speciﬁcation C1329/C1329M.
4.1.1.6 Quicklime—Speciﬁcation C5.
4.1.1.7 Hydrated Lime—Speciﬁcation C207, Types S or SA.
Types N or NA limes are permitted if shown by test or
performance record to be not detrimental to the soundness of
the mortar.
4.1.1.8 Lime Putty—Speciﬁcation C1489.
4.1.2 Aggregates—Aggregates shall conform to Speciﬁca-
tion C144.
4.1.3 Water—Water shall be clean and free of amounts of
oils, acids, alkalies, salts, organic materials, or other substances
that are deleterious to mortar or any metal in the wall.
4.1.4 Admixtures—Admixtures shall not be added to mortar
unless speciﬁed. Admixtures shall not add more than 65 ppm
(0.0065 %) water soluble chloride or 90 ppm (0.0090 %) acid
soluble chloride to the mortar’s overall chloride content, unless
explicitly provided for in the contract documents.
4.1.4.1 Classiﬁed Admixtures—Admixtures which are clas-
siﬁed as bond enhancers, workability enhancers, set
accelerators, set retarders, and water repellents shall be in
accordance with Speciﬁcation C1384.
4.1.4.2 Color Pigments—Coloring pigments shall be in
accordance with Speciﬁcation C979/C979M.
4.1.4.3 Unclassiﬁed Admixtures—Mortars containing ad-
mixtures outside the scopes of Speciﬁcations C1384 and
C979/C979M shall be in accordance with the Property Speci-
ﬁcation and the admixture shall be shown to be non-deleterious
to the mortar, embedded metals, and the masonry units.
4.1.4.4 Calcium Chloride—When explicitly provided for in
the contract documents, calcium chloride is permitted to be
used as an accelerator in amounts not to exceed 2 % by weight
of the portland cement content or 1 % of the masonry cement
content, or both, of the mortar.
NOTE 3—If calcium chloride is allowed, it should be used with caution
as it may have a detrimental effect on metals and on some wall ﬁnishes.
5. Requirements
5.1 Unless otherwise stated, a cement/lime mortar, a mortar
cement mortar, or a masonry cement mortar is permitted. A
mortar type of known higher strength shall not be indiscrimi-
nately substituted where a mortar type of anticipated lower
strength is speciﬁed.
5.2 Proportion Speciﬁcation—Mortar conforming to the
Proportion Speciﬁcation shall consist of a mixture of cemen-
titious material, aggregate, and water, all conforming to the
requirements of Section 4and the Proportion Speciﬁcation’s
requirements of Table 2. See Appendix X1 or Appendix X3 for
a guide for selecting masonry mortars.
5.3 Property Speciﬁcation—Mortar conformance to the
Property Speciﬁcation shall be established by tests of labora-
tory prepared mortar in accordance with Section 6and 7.2. The
laboratory prepared mortar shall consist of a mixture of
cementitious material, aggregate, and water, all conforming to
the requirements of Section 4and the properties of the
laboratory prepared mortar shall conform to the requirements
of Table 1. See Appendix X1 for a guide for selecting masonry
mortars.
5.3.1 No change shall be made in the laboratory established
proportions for mortar accepted under the Property
TABLE 2 Proportion Speciﬁcation Requirements
NOTE 1—Two air-entraining materials shall not be combined in mortar.
Proportions by Volume (Cementitious Materials)
Mortar Type Cement
A
Mortar Cement Masonry Cement Hydrated Lime
or Lime Putty
Aggregate Ratio
(Measured in
Damp, Loose Con-
ditions)
M S N M S N
Cement-Lime M 1 . . . . . . . . . . . . . . . . . .
1
⁄
4
S 1 . . . . . . . . . . . . . . . . . . over
1
⁄
4
to
1
⁄
2
N 1 . . . . . . . . . . . . . . . . . . over
1
⁄
2
to 1
1
⁄
4
O 1 . . . . . . . . . . . . . . . . . . over 1
1
⁄
4
to 2
1
⁄
2
Mortar Cement M 1 . . . . . . 1 . . . . . . . . . . . . Not less than 2
1
⁄
4
and not more than
3 times the sum of
the separate vol-
umes of cementi-
tious materials
M ... 1 ... ... ... ... ... ...
S
1
⁄
2
... ... 1 ... ... ... ...
S ... ... 1 ... ... ... ... ...
N ... ... ... 1 ... ... ... ...
O ... ... ... 1 ... ... ... ...
Masonry Cement M 1 . . . . . . . . . . . . . . . 1 . . .
M ... ... ... ... 1 ... ... ...
S
1
⁄
2
... ... ... ... ... 1 ...
S ... ... ... ... ... 1 ... ...
N ... ... ... ... ... ... 1 ...
O ... ... ... ... ... ... 1 ...
A
Includes Speciﬁcation C150/C150M,C595/C595M, and C1157/C1157M cements as described in 4.1.1.
C270 − 25b
3

文档加载中……请稍候！
如果长时间未打开，您也可以点击刷新试试。

下载文档到电脑，查找使用更方便

亲，本站95%以上的标准规范都面向会员免费，办理VIP会员下载更省钱，平均每篇不到2元

立即下载 VIP免费下载

标签： #标准规范

摘要：

ASTM C270-25b是美国材料与试验协会发布的最新版砌块砌体用砂浆标准规范，适用于新建砌体结构中水泥石灰砂浆、砂浆水泥砂浆和砌筑水泥砂浆的选择与验收。该标准规定了砂浆的四种类型：M型、S型、N型和O型，并分别给出了按配比和按性能两种评定途径。配比法要求按体积比确定水泥、石灰和砂的比例；性能法则要求砂浆在实验室达到规定的抗压强度、抗渗性和耐久性指标。标准同时明确了现场取样、试件制作、养护和试验方法，为工程师、承包商和检测机构提供统一依据。通过符合ASTM C270要求，可有效保证砌体结构的粘

展开>> 收起<<

ASTM C270 - 25b 砌块砌体用砂浆的标准规范.pdf

共14页,预览3页

还剩页未读，继续阅读

声明：本文档系会员上传，若文档所含内容侵犯了您的版权或隐私，请立即通知，我们立即给予侵权申诉删除！

ASTM C270 - 25b 砌块砌体用砂浆的标准规范

相关推荐

开通VIP享超值会员特权

相关内容

热门标签

举报选择: