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Author: Yang Xiaoya. Common problems in masonry project quality involve many aspects; in this article, the author discusses a few of these aspects briefly. The strength of the mortar is low and unstable. There are two situations resulting in low mortar strength: one is that the strength of the mortar specimens cured under standard conditions is low ； Second, the strength of the test blocks is not low, and in some cases even high, but the actual strength of the mortar in the masonry is relatively low. The main reasons for the low strength of standard-cultured test blocks are inaccurate measurement, failure to measure according to the specified ratios, expired cement, and poor quality of sand and plasticizers. Due to inaccurate measurement, the variability in mortar strength is bound to be high. The main preventive measures are: strengthening on-site management and enhancing measurement control. The mortar has poor workability and tends to harden at the bottom. Poor workability is mainly manifested in the mortar’s viscosity and water retention not meeting the specified standards; this leads to sedimentation and bleeding, making it difficult to spread and compact the mortar. As a result, the quality of masonry is affected, and the adhesion between the mortar and bricks is reduced. Preventive measures include: avoiding the use of high-strength cement in low-strength cement mortar, not using fine sand, strictly controlling the quality and dosage of plasticizing materials, enhancing the planning behind mortar mixing so that it is used immediately after mixing, and frequently stirring the mortar in the containers to remove any sediment at the bottom. The incorrect method of stacking bricks leads to issues such as multiple layers of bricks sharing the same joint line (continuous or straight joints), with two layers of bricks on the inside and outside; brick columns are constructed using a core-wrapping technique, resulting in the inner and outer layers of bricks not interlocking with each other and the formation of continuous gaps around them. These problems affect the strength of the masonry and reduce the structural integrity. Preventive measures include providing workers with enhanced technical training, assembling bricks strictly in accordance with standard methods, using defective bricks in a dispersed manner, minimizing the use of half-bricks, and prohibiting the use of broken bricks. The mortar joints in the wall surfaces are not straight; they are uneven, causing the wall surface to be irregular. The horizontal mortar joints are curved and not straight, the thickness of the mortar joints varies, resulting in a \"screw\"-shaped wall. The vertical mortar joints are tilted, and their widths are inconsistent; moreover, the bricks in the vertical alignment are not centered over those in the horizontal alignment, leading to an uneven wall surface. Preventive measures include laying a base layer before bricklaying, and adjusting the mortar joints according to the actual size of the bricks ； Masonry is carried out using a line-tightening rod; the short side of the bricks is aligned with the line. When the length of the line (15–20 m) is too great, a belt course should be added ； For vertical joints, ink lines should be drawn at regular intervals to ensure alignment; these ink lines are determined using a plumb line. For each layer of masonry, a vertical line is drawn upward, and the vertical line, horizontal line, and plumb line must all be in alignment. Incorrect joint formation in walls: When building walls, straight joints or even improper types of joints are used arbitrarily; the joints at structural columns are not formed properly, and the joint gaps are filled with brick debris. The mortar used to fill these joints is not applied properly, which affects the strength of the masonry in those areas and reduces the overall integrity of the structure. Preventive measures include: uniform consideration of joint formation in the construction organization plan, strict adherence to specification requirements for such joints, and the use of a 18-layer joint-backing build with bricks ning method – with the height of the interlocking joints being five layers for standard bricks and three layers for perforated bricks ； The joints left at the construction openings should be protected and covered to prevent material transport vehicles from hitting them. The horizontal reinforcement bars for tying together rebar are often omitted; in structural columns and joints, such bars are frequently missed or not arranged as required. The mortar filling the gaps between bricks where rebar is present is not sufficient, and exposed rebar tends to rust over time. Preventive measures include treating tie rods as items subject to hidden inspection, strengthening inspections, and filling out inspection records for archiving. During construction, the required reinforcement for the areas being constructed should be prepared all at once, so as to check for any omissions. Try to use spot-welded steel rebar mesh, and increase the thickness of the mortar joints appropriately (it is advisable to have a protective layer of 2 mm on each side of the rebar mesh thickness). Cracks in block walls: Block walls are prone to horizontal cracks running along the floor slabs, vertical cracks in the middle of the window sills on the ground floor, stepped-shaped cracks at the corners on the top floor, as well as cracks around the blocks. The preventive measure is: to reduce shrinkage, the blocks should be given sufficient time to rest after being taken out of the tank (30–50 days) ； Remove the release agent and dust from the surface of the bricks, etc ； Masonry should be constructed using mortar with strong adhesion and good workability, while controlling the length of the mortar application and the thickness of the mortar joints ； Install core columns, ring beams, and expansion joints; locally provide horizontal reinforcement in areas that are particularly sensitive to temperature and shrinkage. Wall leakage: Leakage and water seepage often occur around block walls as well as door and window frames. Preventive measures include carefully checking the quality of the blocks, especially their water resistance ； Strengthen the control of the fullness of grout mortar ； Eliminate wall cracks ； Sealing around the door and window frames should be carried out before plastering the wall surfaces, and it must be done after the mortar (or fine aggregate concrete) used to fix the metal feet of the frames has reached a certain strength. Excessively high floor height: The actual floor height deviates from the designed height by more than the allowable margin. Preventive measures include ensuring that the raw materials used for preparing the masonry mortar meet quality standards, as well as controlling the thickness and length of the mortar layer ； Before starting the masonry work, it is necessary to calculate the number of layers required based on the dimensions and specifications of the blocks, beams, and slabs; a layering guide should be prepared. During construction, it is important to control the height of each layer of blocks. Any errors in the elevation of the original floor can be adjusted layer by layer, as long as such adjustments remain within the allowable tolerances for filling the joints or for leveling the ring beams and floor slabs. In our actual work, we should pay attention to the points mentioned above, strengthen preventive measures, and ensure the quality of masonry works.