Your current location：Home > Information > Material knowledge > text
Mortar bonding is not good, what to do?
Update time：2017-09-08 00:42:10clicks：2200次Type size：T|T
Let's talk about the phenomenon of poor mortar bonding:
The filling degree of mortar in the horizontal mortar joint of masonry is less than 80%; Vertical joints appear blind joints, especially hollow brick walls, often appear more transparent joints, masonry wall to adopt large shrinkage of the ash, shrinkage joint depth even up to 20mm or more, affecting the mortar fullness. Bricks are not watered and moistened before masonry, dry bricks are on the wall, or the ash is laid too long, resulting in poor adhesion between mortar and bricks.
Analysis of reasons for poor bonding between mortar and brick
1, low-strength mortar, such as the use of cement mortar, due to the poor workability of cement mortar, masonry extrusion effort, the operator with a big shovel or tile knife after scraping mortar, so that the bottom ash produced holes, mortar is not full.
2, with the dry brick wall, the mortar early dehydration and reduce the strength, and the adhesion with the brick decreases, and the dust on the surface of the dry brick plays an isolating role, weakening the bond between the brick and the mortar layer.
3, with the slurry laying method, sometimes because the slurry is too long, the masonry speed can not keep up, the moisture in the mortar is absorbed by the bottom brick, so that the brick layer and the mortar lose the bond.
4. When building clean wall, in order to save the scraping process, the method of laying ash with large shrinkage is adopted, so that the depth of the shrinkage of the masonry brick is more than 20mm, which not only reduces the fullness of the mortar, but also increases the workload of pointing.
Prevention and control measures
1. Improving the workability of mortar is the key to ensuring the fullness of mortar and improving the bond strength. The choice of mortar raw materials is very important. Sand cement should be within the shelf life, and the thickening agent cellulose ether and the dispersible emulsion powder that improve the adhesion of mortar should be selected from regular enterprises.
2, improve the masonry method. It is not appropriate to adopt the slurry laying method or swing brick masonry, and the "trinity bricklaying method" should be promoted, that is, the masonry method of using a large shovel, a brick, a shovel of ash, and a squeeze and kneading.
3, when the slurry laying method is used, the length of the slurry must be controlled, the general temperature shall not exceed 750mm, and when the temperature exceeds 30℃ during the construction period, it shall not exceed 500mm.
4, strictly prohibited for brick walls. Bricks should be watered 1 ~ 2d before masonry, so that the moisture content of sintered ordinary bricks and porous bricks during masonry can reach 10% ~ 15%; The moisture content of lime sand brick and fly ash brick reaches 8% ~ 12%.
5, in the winter construction, the brick surface should also be properly wet under positive temperature conditions before masonry. When brick cannot be poured under negative temperature construction, the consistency of mortar should be appropriately increased. For the 9-degree seismic fortification area, masonry cannot be carried out in the case that bricks cannot be fired in severe winter.
Article source： Keyword：
The filling degree of mortar in the horizontal mortar joint of masonry is less than 80%; Vertical joints appear blind joints, especially hollow brick walls, often appear more transparent joints, masonry wall to adopt large shrinkage of the ash, shrinkage joint depth even up to 20mm or more, affecting the mortar fullness. Bricks are not watered and moistened before masonry, dry bricks are on the wall, or the ash is laid too long, resulting in poor adhesion between mortar and bricks.
Analysis of reasons for poor bonding between mortar and brick
1, low-strength mortar, such as the use of cement mortar, due to the poor workability of cement mortar, masonry extrusion effort, the operator with a big shovel or tile knife after scraping mortar, so that the bottom ash produced holes, mortar is not full.
2, with the dry brick wall, the mortar early dehydration and reduce the strength, and the adhesion with the brick decreases, and the dust on the surface of the dry brick plays an isolating role, weakening the bond between the brick and the mortar layer.
3, with the slurry laying method, sometimes because the slurry is too long, the masonry speed can not keep up, the moisture in the mortar is absorbed by the bottom brick, so that the brick layer and the mortar lose the bond.
4. When building clean wall, in order to save the scraping process, the method of laying ash with large shrinkage is adopted, so that the depth of the shrinkage of the masonry brick is more than 20mm, which not only reduces the fullness of the mortar, but also increases the workload of pointing.
Prevention and control measures
1. Improving the workability of mortar is the key to ensuring the fullness of mortar and improving the bond strength. The choice of mortar raw materials is very important. Sand cement should be within the shelf life, and the thickening agent cellulose ether and the dispersible emulsion powder that improve the adhesion of mortar should be selected from regular enterprises.
2, improve the masonry method. It is not appropriate to adopt the slurry laying method or swing brick masonry, and the "trinity bricklaying method" should be promoted, that is, the masonry method of using a large shovel, a brick, a shovel of ash, and a squeeze and kneading.
3, when the slurry laying method is used, the length of the slurry must be controlled, the general temperature shall not exceed 750mm, and when the temperature exceeds 30℃ during the construction period, it shall not exceed 500mm.
4, strictly prohibited for brick walls. Bricks should be watered 1 ~ 2d before masonry, so that the moisture content of sintered ordinary bricks and porous bricks during masonry can reach 10% ~ 15%; The moisture content of lime sand brick and fly ash brick reaches 8% ~ 12%.
5, in the winter construction, the brick surface should also be properly wet under positive temperature conditions before masonry. When brick cannot be poured under negative temperature construction, the consistency of mortar should be appropriately increased. For the 9-degree seismic fortification area, masonry cannot be carried out in the case that bricks cannot be fired in severe winter.
Article source： Keyword：
