Mortar Retention Rate Tester

Product Information:

The determination of water retention rate in cement mortar uses freshly mixed mortar within a specified fluidity range, which is then treated according to a prescribed method for absorption. The water retention rate of the mortar is the mass of water retained in the mortar after the absorption treatment, expressed as a percentage of the original water volume.

1. Weigh the empty, dry mold to 0.1g; weigh 8 unused filter papers to 0.1g.

2. Weigh 450±2g of cement, 1350±5g of ISO standard sand, and measure 225±1ml of water. Prepare the mortar according to GB/T17671, and determine the mortar's fluidity according to GB/T2419. Adjust the water volume based on the amount used to achieve a cement-sand mortar fluidity within the range of 180-190mm.

When the mortar's consistency is between 180-190mm, remix the remaining mortar in the mixing boiler at low speed for 15 seconds, then fill and level the surface of the mortar into the test mold using a spatula.

4.Weigh the molds filled with mortar.0.1g, cover the mortar surface with a sieve, and place 8 pre-weighed filter papers on top of the sieve. Place a rigid base on the filter papers, invert the mold 180° and place it flat, with a 2kg iron weight on the inverted mold base. Remove the iron weight after 5 minutes ± 5 seconds, invert the mold again, remove the rigid base; sieve and filter papers, and weigh the filter papers to 0.1g.

5. Specifications and Parameters

Ring: Internal Diameter100 mm±1 mm，Internal Effective Depth25 mm±1 mm

Base and cover plate: diameter100 mm ± 5 mm, thickness 5 mm ± 1 mm

Filter Paper: Diameter of110 mm±1 mm，Filter Paper100 pieces

Stainless Steel Filter Mesh: Mesh Size45μm = 325 mesh per sheet

Weighing weights: weight of2 kg