Chapter 1 General
Article 1.0.1 This standard is formulated to adopt uniform test methods for determining the property characteristic value of construction mortar as well as inspecting or controlling the quality of on-site mixed mortar.
Article 1.0.2 This standard is applicable to the basic property test of construction mortar which is mainly mixed by cement, sand, lime and admixture and is used for the masonry and plastering of building construction and general structures.
Article 1.0.3 The mortar property test in this standard shall not only comply with the relevant requirements of this standard, but also meet the requirements of current relevant standards.
Chapter II Mixture Sampling and Sample Preparation
Article 2.0.1 The material for construction mortar test may be taken from the mortar delivered by the same blender or vehicle according to different requirements; as for sampling in test room, it may be taken from mortar mixed by machinery or by manpower.
Article 2.0.2 Where sampling is carried out for mortar test during construction, the sampling method and principle shall comply with the corresponding code of construction acceptance. It shall be sampled from at least three different positions at the mortar carrier, mortar conveyer and blender outlet in application site. The quantity of samples shall be 1~2 times more than materials used for test.
Article 2.0.3 Where mixed mortar is tested in test room, the materials for mixture shall be delivered into the test room in advance; during mixing, the temperature of the test room shall be kept at 20±5℃.
Note: If it need imitate the mortar used under construction conditions, the temperature of raw materials at the test room should be kept the same as that at construction site.
Article 2.0.4 The cement and other raw materials for the test shall be consistent with those for field use. If there is agglomeration in the cement, it shall be fully and uniformly mixed and shall be sifted by 0.9mm sieve; the sand shall also be sifted by 5mm sieve.
Article 2.0.5 Where mortar is mixed in test room, the materials shall be weighed and measured. The accuracy of weighing shall be as follows: ±0.5% for cement and additive; ±1% for sand, lime putty, clay puddle, fly ash and ground quick lime power.
Article 2.0.6 Where blender is used to mix mortar in the testing room, the mix content should be greater than or equal to 20% of the blender volume and the mixing time should be greater than or equal to 2min.
Article 2.0.7 After sampling mortar mixture, it shall be tested rapidly. The samples taken on site shall be mixed again by manpower before the test to guarantee uniform mass.
Contents
Chapter 1 General
Chapter II Mixture Sampling and Sample Preparation
Chapter III Consistency Test
Chapter IV Density Test
Chapter V Coursing Degree Test
Chapter VI Determination of Setting Time
Chapter VII Compressive Strength Test of Cube
Chapter VIII Elastic Modulus Test during Static Compression
Chapter IX Freezing Resistance Test
Chapter X Shrinkage Test
Appendix Explanation of Wording in This Code
Additional Explanation Chief Development Organizations, Participating Organizations and Chief Drafting Staffs
Chapter 1 General
Article 1.0.1 This standard is formulated to adopt uniform test methods for determining the property characteristic value of construction mortar as well as inspecting or controlling the quality of on-site mixed mortar.
Article 1.0.2 This standard is applicable to the basic property test of construction mortar which is mainly mixed by cement, sand, lime and admixture and is used for the masonry and plastering of building construction and general structures.
Article 1.0.3 The mortar property test in this standard shall not only comply with the relevant requirements of this standard, but also meet the requirements of current relevant standards.
Chapter II Mixture Sampling and Sample Preparation
Article 2.0.1 The material for construction mortar test may be taken from the mortar delivered by the same blender or vehicle according to different requirements; as for sampling in test room, it may be taken from mortar mixed by machinery or by manpower.
Article 2.0.2 Where sampling is carried out for mortar test during construction, the sampling method and principle shall comply with the corresponding code of construction acceptance. It shall be sampled from at least three different positions at the mortar carrier, mortar conveyer and blender outlet in application site. The quantity of samples shall be 1~2 times more than materials used for test.
Article 2.0.3 Where mixed mortar is tested in test room, the materials for mixture shall be delivered into the test room in advance; during mixing, the temperature of the test room shall be kept at 20±5℃.
Note: If it need imitate the mortar used under construction conditions, the temperature of raw materials at the test room should be kept the same as that at construction site.
Article 2.0.4 The cement and other raw materials for the test shall be consistent with those for field use. If there is agglomeration in the cement, it shall be fully and uniformly mixed and shall be sifted by 0.9mm sieve; the sand shall also be sifted by 5mm sieve.
Article 2.0.5 Where mortar is mixed in test room, the materials shall be weighed and measured. The accuracy of weighing shall be as follows: ±0.5% for cement and additive; ±1% for sand, lime putty, clay puddle, fly ash and ground quick lime power.
Article 2.0.6 Where blender is used to mix mortar in the testing room, the mix content should be greater than or equal to 20% of the blender volume and the mixing time should be greater than or equal to 2min.
Article 2.0.7 After sampling mortar mixture, it shall be tested rapidly. The samples taken on site shall be mixed again by manpower before the test to guarantee uniform mass.
Contents of JGJ 70-1990
Contents
Chapter 1 General
Chapter II Mixture Sampling and Sample Preparation
Chapter III Consistency Test
Chapter IV Density Test
Chapter V Coursing Degree Test
Chapter VI Determination of Setting Time
Chapter VII Compressive Strength Test of Cube
Chapter VIII Elastic Modulus Test during Static Compression
Chapter IX Freezing Resistance Test
Chapter X Shrinkage Test
Appendix Explanation of Wording in This Code
Additional Explanation Chief Development Organizations, Participating Organizations and Chief Drafting Staffs
