Astm c270 pdf free download

Successive deposits X1. Such autogenous healing will durability, is subjected to repeated cycles of freezing and tend to reduce water permeance.

Unless a masonry assemblage is allowed to become nearly saturated, there is little danger of substantial damage X1. Properly entrained air in masonry mortar of its weight in calcium hydroxide at complete hydration.

This generally increases its resistance to freeze-thaw damage where calcium hydroxide performs the same as lime during extreme exposure such as repeated cycles of freezing and carbonation, solubilizing, and redepositing.

Air content within X1. Dura- constituent of the mortar. Sand acts as an inert filler, providing. An increase in sand content increases entrainment, water retentivity, workability, accelerated set, and the setting time of a masonry mortar, but reduces potential so on.

Limited data are available regarding the effect of cracking due to shrinkage of the mortar joint. The special or proprietary admixtures on mortar bond, compressive strength, standard sand required for certain laboratory mortar tests may or water permeance of masonry.

Field experience indicates that produce quite different test results from sand that is used in the detrimental results have frequently occurred. For these reasons, construction mortar. Sands deficient in fines produce harsh mortars, masonry.

High lime or high air content mortars can limits on air content in a field mortar, still continues to create carry more sand, even with poorly graded aggregates, and still controversy. Most masonry cements, all Type A portland provide adequate workability. Excess fines in the sand, mum as well as maximum levels of air in a laboratory mortar. Mortar stances. At high air levels, a definite inverse selection.

Often gradation can be easily and sometimes inex- relationship exists between air content and tensile bond pensively altered by adding fine or coarse sands. Frequently the strength of mortar as measured in the laboratory. In general, most feasible method requires proportioning the mortar mix to any increase in air content is accompanied by a decrease in suit the available sand within permissible aggregate ratio bond as well as compressive strength.

Data on masonry grouts tolerances, rather than requiring sand to meet a particular indicate that lower bond strength between grout and reinforc- gradation.

Most highly air X1. It contrib- entrained mortar systems can utilize higher sand contents utes to workability, hydrates cement, and facilitates carbon- without losing workability, which could be detrimental to the ation of lime. The amount of water needed depends primarily masonry if excessive sand were used.

The use of any mortar on the ingredients of the mortar. Water should be clean and free containing air entraining materials, where resulting levels of air from injurious amounts of any substances that may be delete- are high or unknown, should be based on a knowledge of local rious to mortar or metal in the masonry. Usually, potable water performance or on laboratory tests of mortar and masonry is acceptable.

Water requirement the field is strongly discouraged. Mortars should contain the aggregates or inorganic pigments. Mortar should also be retempered to replace water lost by of the weight of portland cement, with carbon black limited to evaporation. To minimize hardened mortar physically or chemically. The inclusion of an additive is also necessary for the plant or to use preweighed individual packets of coloring production of ready mixed mortars.

Undoubtedly there are also compounds for each batch of mortar, and to mix the mortar in some special situations where the use of admixtures may be batches large enough to permit accurate batching. Mortar advantageous when added at the job site mixer. In general, mixing procedures should remain constant for color consis- however, such use of admixtures is not recommended.

Careful tency. Improprieties cannot be corrected by admixtures, some of which are defi- X1. When the first settlements appeared in North America, a workability loss in the mortar. The use of ready mixed mortar relatively weak product was still being made from lime and is also on the increase. These are mixtures consisting of sand. The common use of portland cement in mortar began in cementitious materials, aggregates, and admixtures, batched the early part of the twentieth century and led to greatly and mixed at a central location, and delivered to the construc- strengthened mortar, either when portland cement was used tion project with suitable workability characteristics for a alone or in combination with lime.

Modern mortar is still made period in excess of h after mixing. Systems utilizing with from portland cement and hydrated lime, in addition to continuous batching of mortar are also available.

At one extreme, a qualification as Types M and S Mortars in this specification. A wall contain- X1. At the other extreme, a straight lime and any project with the desired performance characteristics are the sand mortar would have low compressive strength and high design, material, procedure and craftsmanship selected and water retention. A wall containing such a mortar would have used.

Between the two compliance with requirements should be appropriate and extremes, various combinations of cement and lime provide a predetermined.

Selective pro- soon as the masonry unit and the mortar come into contact. The portions are found in this specification. Microscopic bubbles of en- the mortar and the masonry units, and thus the strength, as well trained air contribute to the ball bearing action and provide a as other properties, of the masonry assemblage.

Freeze-thaw durability of masonry X1. Three types of important external factor which affects the fresh mortar and masonry cement are recognized by Specification C These initiates the development of bond. Masonry units vary widely masonry cements are formulated to produce mortars conform- in initial rate of absorption suction. It is therefore necessary ing to either the proportion or the property specifications of this that the mortar chosen have properties that will provide specification.

Such masonry cements provide the total cemen- compatibility with the properties of the masonry unit being titious material in a single bag to which sand and water are used, as well as environmental conditions that exist during added at the mixer.

A consistent appearance of mortar made construction and the construction practices peculiar to the job. More than X1. A loss of too much water from recognized by Specification C These mortar cements are the mortar can be caused by low water retentivity mortar, high formulated to produce mortar conforming to either the propor- suction masonry units, or dry, windy conditions.

When this tion or property requirements of this specification. Mortar occurs, the mortar is incapable of forming a complete bond cement mortars have attributes similar to those of masonry when the next unit is placed. Where lowering the suction by cement mortars while satisfying air content and bond strength prewetting the units is not proper or possible, the time lapse requirements of Specification C When a very low suction premixed mortars have been made readily available in two masonry unit is used, the unit tends to float and bond is difficult options.

One is a wet, ready mixed combination of hydrated to accomplish. There is no available means of increasing the lime or lime putty, sand, and water delivered to the construc- suction of a low suction masonry unit, and thus the time lapse tion project, and when mixed with cement and additional water between spreading the mortar and placing the unit may have to is ready for use.

The other is dry, packaged mortar mixtures be increased. Special X1. Mortars having lower water retentivity are desirable overcome the water affinity of oven dry sand and subsequent for use in winter or with masonry units having low suction. Although compressive strength of the mortar mortar once contact has been achieved affects the quality of the is reduced slightly by retempering, bond strength is usually mortar joint.

Protection should be provided to prevent exces- increased. For this reason, retempering should be required to sive wetting, drying, heating or cooling, until the mortar has at replace water lost by evaporation. Because retempering is least achieved final set. During warm, dry, windy, summer Cementitious materials and aggregate should be protected from weather, mortar must have a high water retentivity to minimize rain and ground moisture and air borne contaminants.

In winter, a lower water X1. To minimize the risk of box for measuring sand. When necessary, sand quantities reduced bond in cold weather, the masonry units being used as should be adjusted to provide for bulking of the sand.

Shovel well as the surface on which the mortar is placed should both measuring cannot be expected to produce mortar of consistent be brought to a temperature at least above 32F 0C before quality. Alternatively, a combination volumetric measure cali- any work commences.

For more inclusive suggestions, see bration of a mixer followed by full bag cementitious additions Recommended Practices for Cold Weather Masonry Con- and shovel additions of sand to achieve the same volume of struction available from the International Masonry Industry mortar in the mixer with subsequent batches, should prove All Weather Council.

The time lapse between three-fourths of the required water, one-half of the sand, and all spreading mortar and placing masonry units should be kept to of the cementitious materials are briefly mixed together.

The a minimum because the flow will be reduced through suction of balance of the sand is then charged and the remaining water the unit on which it is first placed. This time lapse should added. The mixer should be charged to its full design capacity normally not exceed one minute. Reduce this time lapse for for each batch and completely emptied before charging the hot, dry and windy conditions, or with use of highly absorptive next batch. If excessive time elapses before a unit is placed X1.

Elimination of deep minimum of 3 and a maximum of 5 min after the last mixing furrows in horizontal bed joints and providing full head joints water has been added, to insure homogeneity and workability are essential. Any metal embedded in mortar should be of the mortar. Overmixing results in changing the air content of completely surrounded by mortar. Worn paddles and rubber scrapers will greatly X1.

Concern for quality suggests to stiffen, tapping or otherwise attempting to move masonry use of an automatic timer on the mixing machine. Mixing time units is highly detrimental to bond and should be prohibited. The movement breaks the bond between the mortar and the X1. Exterior, at or below grade foundation wall, retaining wall, SC M or NC manholes, sewers, pavements, walks, and patios.

Interior load-bearing wall N S or M non-bearing partitions O N Interior or Exterior tuck pointing see Appendix X3 see Appendix X3 A This table does not provide for many specialized mortar uses, such as chimney, reinforced masonry, and acid-resistant mortars.

B Type O mortar is 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 nominally horizontal surface is extremely vulnerable to weathering. Mortar for such masonry should be selected with due caution. Joint expense of others. Testing of mortars in the laboratory by this configurations other than concave can result in increased water specifications referenced methods, and in the field by Test permeance of the masonry assemblage.

Striking joints with the Method C is beneficial. Some physical properties of mortar, same degree of hardness produces uniform joint appearance. When between mortar and masonry unit, while densifying the surface selecting a mortar, evaluate all properties, and then select the of the mortar joint.

Use of X1. Many variables affect bond. To detrimental to the mortar. Colored mortars are especially obtain optimum bond, use a mortar with properties that are susceptible to damage from such cleaning. Most chemicals compatible with the masonry units to be used. To increase used in cleaning attack the cementitious materials within the tensile bond strength in general, increase the cement content of mortar system, as well as enlarge cracks between mortar and the mortar see X1.

Curing of mortar by the initial rates of absorption when laid see X1. The addition of excess moisture might saturate the subsequently disturb laid units. Selection of X1. There is no ASTM test water soluble salts on the surface of masonry. The principal method that will predict the potential for efflorescence of objection to efflorescence is the appearance of the salts and the mortar. Further, there is no ASTM test method to evaluate the nuisance of their removal.

Under certain circumstances, par- efflorescence potential of combined masonry materials. When this X2. Masonry units with a rating of not effloresced are the least likely to contribute towards efflorescence. First, there must be a source of cement decreases. Admixtures should not be used in the field. Second, there must be moisture present to pick up Washed sand and clean, potable water should be used.

Third, evapo- ration or hydrostatic pressure must cause the solution to X2. If any one of these conditions is eliminated, efflores- Attention must be paid to the design and installation of cence will not occur. During construction, X2. Water- from rain and construction applied water.

Condensation occurring out and concentrated on the surface. The amount and character within the masonry is a further source of water.

A test for the X2. Efflorescence can occur with any C of moisture migration through the wall holds the greatest. Design of masonry using are highly soluble in water, they will disappear of their own the principle of pressure equalization between the outside and accord under normal weathering processes.

Some salts, a void space within the wall will greatly reduce the chances of however, may require harsh physical or even chemical water penetration and subsequently efflorescence.

Since many salts. Mortars made without portland cement exterior, above grade exposed O N,K on one side, unlikely to be may require special considerations in selecting tuck pointing frozen when saturated, not mortars. A In some applications, structural concerns may dictate the use of mortars other An exact match is virtually impossible to achieve. This table is not applicable to pavement applications.

NOTE X3. Sand may be selected to have color, size, X3. Mix from 3 same or weaker composition as the original mortar. See Table to 7 min, preferably with a mechanical mixer. Aggregate Ratio of to 3 times sum of X3. Permit tempering of the mortar within this time interval. The weights of the. ASTM International takes no position respecting the validity of any patent rights asserted in connection with any item mentioned in this standard.

Users of this standard are expressly advised that determination of the validity of any such patent rights, and the risk of infringement of such rights, are entirely their own responsibility. This standard is subject to revision at any time by the responsible technical committee and must be reviewed every five years and if not revised, either reapproved or withdrawn.

Your comments are invited either for revision of this standard or for additional standards and should be addressed to ASTM International Headquarters. Your comments will receive careful consideration at a meeting of the responsible technical committee, which you may attend. If you feel that your comments have not received a fair hearing you should make your views known to the ASTM Committee on Standards, at the address shown below.

Individual reprints single or multiple copies of this standard may be obtained by contacting ASTM at the above address or at phone , fax , or service astm.

Open navigation menu. Close suggestions Search Search. User Settings. Skip carousel. Carousel Previous. Carousel Next. What is Scribd? Astm C Uploaded by asdrecv. Did you find this document useful? Is this content inappropriate? Report this Document. Flag for inappropriate content. Download now. Related titles. Carousel Previous Carousel Next. Jump to Page. Search inside document. Designation: C 14a Standard Specification for Mortar for Unit Masonry1 This standard is issued under the fixed designation C; the number immediately following the designation indicates the year of original adoption or, in the case of revision, the year of last revision.

Since many salts X3. The weights of the ASTM International takes no position respecting the validity of any patent rights asserted in connection with any item mentioned in this standard. Gita Tawankz. Edwin R Ruiz. Janika Ketratnkul. South Santa Fe Drive. Work Item s — proposed revisions of this standard. This x covers mortars for use in the construction of non-reinforced and reinforced unit masonry structures.

Four types of mortar are covered in each of two alternative specifications: The property specification applies to mortar mixed to a specific flow in the laboratory. When neither proportion nor property specifications are specified, the proportion specifications d govern, unless data are presented to and accepted by c20 specifier to show that mortar meets the requirements of the property specifications.

This specification does not cover the determination of mortar strengths through field testing. The compressive strength values resulting from field tested mortars do not represent the compressive strength of mortar 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 of rejection of the mortar.

Compliance to this specification is verified by confirming that the materials used are as specified, meet the requirements as given, and added to the mixer in the proper proportions as described. This abstract is a brief summary of the referenced standard. It is informational only and not an official part of the standard; the full text of the standard itself must be referred to for its use and application. ASTM does not give any warranty express or implied or make any representation that the contents of this 2c70 are accurate, complete or up to date.

When the property specification is used to qualify masonry mortars, the testing agency performing the test methods should be evaluated in accordance with Practice C These notes and footnotes excluding those in tables and figures shall not be considered as requirements of the standard.

The values given in parentheses are mathematical conversions to SI units that are provided for information only and are not considered standard. 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 and health practices and determine the applicability of regulatory limitations prior to use.

Referenced Documents purchase separately The documents listed below are referenced within the subject standard but are not provided zstm part of the standard.