What should be done if the plastering mortar lacks sufficient strength?
Release Time:
2015-08-05
Source:
What should be done if the plastering mortar lacks sufficient strength?
It is well known that mortar for interior plastering typically includes admixtures. When insufficient strength is observed in on-site interior plastering, what is the best way to address this issue?
If strict requirements are to be met, one should try mixing lime putty with cement and river sand according to the design-specified proportions. As for plastering mortar, there are no specified strength grades; only volume ratios are prescribed. The use of admixtures is an inappropriate practice and has now been strictly prohibited in many first- and second-tier cities. In fact, the so-called external Additives are used to replace lime paste, thereby improving the workability of mortar. The reason for restricting the use of lime paste is that it is a raw material composed of chemical ingredients. Its product quality is highly unstable because the production process is very simple, making it impossible to guarantee consistent quality, and many… There are numerous quality issues. Consequently, many first- and second-tier cities have already imposed a strict ban on its use. As for the problem of insufficient strength in plastering mortar, the real culprit lies in the cement. This is because, in decorative construction projects, cement does not typically undergo rigorous, standardized inspections. Often, to cut costs, contractors purchase cement from small, unregulated manufacturers. In the case of mud, a considerable portion of the cement used fails to meet strength requirements or has expired, which is the root cause of the strength issues. This has nothing to do with lime paste. As long as the raw materials are of assured quality in accordance with design specifications and the mix proportions and mixing procedures comply with relevant codes and standards, such problems will not arise.
In summary, the following issues should be given attention:
1. Applying a bonding agent is not the standard practice; if the wall plaster exhibits sanding or insufficient strength, it should be removed and the work redone.
2. For wall surfaces that have not yet dried or have just begun to set, enhance curing to increase the mortar’s strength.
3. For work that has not yet commenced, discontinue the use of mortar admixtures and increase the cement dosage.
4. Prior to construction, implement rigorous quality control over materials, including monitoring the silt content of yellow sand and conducting cement tests, and strictly adhere to the specified mix proportions.
