1.0.1 This Specification was formulated with a view to unifying the technical conditions and mix proportion design methods of the masonry mortar, satisfying the design and construction requirements, guaranteeing the quality of the masonry mortar and achieving the advanced technology and economic feasibility.
1.0.2 This Specification is applicable to the mix proportion design of the masonry mortar adopted in industrial and civil buildings as well as general structures.
1.0.3 The mix proportion design of the masonry mortar shall be calculated or selected through table searching according to the performance of raw materials, technical requirements of the mortar, kind of block as well as construction conditions, and shall be determined after trial mix and adjustment.
1.0.4 The mix proportion design of the masonry mortar shall not only meet this Specification, but also comply with those specified in the current relevant ones of the Nation.
2 Terms
2.0.1 Masonry mortar
It refers to the mortar that is able to mason such block materials as bricks, stones and masonry blocks into the masonry, functioned as bonding, gasket and force transmission.
2.0.2 Masonry mortar site mixing
It refers to the mortar that site mixed with the cement, fine aggregate and water as well as lime, active additives or admixtures added as required, which is divided into cement mortar and cement composite mortar.
2.0.3 Ready-mixed mortar
It refers to the wet mixing mortar or dry mixing mortar produced by professional production plant.
2.0.4 Water-retentive and plastic material
It refers to the non-lime material that can improve the operability and water-retaining property of the mortar.
3 Materials Requirements
3.0.1 The raw materials used for masonry mortar shall not cause harmful influence on the human body, living beings and the environment, and shall meet the requirements of the current national standard "Limit of Radionuclides in Building Materials" (GB 6566).
3.0.2 The cement should adopt the common portland cement or masonry cement and shall meet the requirements of the current national standards "Common Portland Cement" (GB 175) and "Masonry Cement" (GB/T 3183). The cement strength grade shall be selected according to the requirements of the mortar variety and strength grade. The masonry mortar with the strength grade of M15 or below should adopt Grade 32.5 common portland cement or masonry cement; the masonry mortar with the strength grade of M15 above should adopt Grade 42.5 common portland cement.
3.0.3 The sand should adopt medium sand, shall meet the requirements of the current professional standard "Standard for Technical Requirements and Test Method of Sand and Crushed Stone (or Gravel) for Ordinary Concrete" (JGJ 52), and shall all get through 4.75mm sieve meshes.
3.0.4 The lime putty and calcium carbide sludge used for the masonry mortar shall meet the following requirements:
1 When the quick lime is slaking to lime putty, it shall be filtered through the mesh with hole diameter no larger than 3mm×3mm, and the time of slaking shall not be less than 7d; the time of slaking for the ground quick lime power shall not be less than 2d. The drying, freezing and pollution prevention measures shall be taken for the lime putty stored in the settling pond. It is strictly forbidden to use dehydrated and hardened lime putty.
2 The carbide slag used for making calcium carbide sludge shall be filtered through the mesh with hole diameter not be larger than 3mm×3mm, it shall be heated to 70℃ and kept for at least 20min when inspecting, and shall be reused only after the acetylene has been volatilized completely.
3 The slaked lime powder shall not be directly used in the masonry mortar.
3.0.5 The consistency of the lime putty and calcium carbide sludge when trial mix shall be 120mm±5mm.
3.0.6 The fly ash, ground granulated blast furnace slag, silica fume and natural zeolite powder shall respectively meet the requirements of the current national standards "Fly Ash Used for Cement and Concrete" (GB/T 1596), "Ground Granulated Blast Furnace Slag Used for Cement and Concrete" (GB/T 18046), "Mineral Admixtures for High Strength and High Performance Concrete" (GB/T 18736) and "Technical Specification for Application of Natural Zeolite Powder in Concrete and Mortar" (JGJ/T 112). When the mineral additives of other variety are adopted, they shall be provided with reliable technical base and shall be verified through tests before application.
3.0.7 When the water-retentive and plastic material is adopted, it shall be verified through tests before application and shall have complete type inspection reports.
3.0.8 The admixtures shall meet the requirements of the current relevant standards of the Nation; air entraining admixtures still shall be equipped with complete type inspection reports.
3.0.9 The water for mixed mortar shall meet the requirements of the current professional standard "Standard of Water for Concrete" (JGJ 63).
