What is splitting bricks?
Although the traditional split brick has high decorative value and strong artistic and humanistic atmosphere, it is not suitable for the flexible characteristics of external wall insulation materials because of its complicated manufacturing process and complicated construction, especially the rigid characteristics of split bricks, and there are bound to be problems such as cracking, water seepage, falling off and jointing. Moreover, a large amount of waste gas produced in the firing process in split brick will pollute the air environment, which is not conducive to environmental protection.
Modern split brick retains and highlights the unique groove texture of traditional split brick without losing its delicate touch and moist luster, which simulates the forming process of traditional split brick to the greatest extent, reproduces the decorative pattern of split brick and achieves a miraculous overall decorative effect. According to the color matching of traditional split brick, modern split brick series has many colors to choose from, such as red, yellow, brown and gray, and natural mineral powder is used, which will never fade. 、
In today's busy and fast urban life, people pursue more green, natural and simple natural tastes. Split brick, with its natural texture and smooth surface, adds a lot of cultural connotation and quiet temperament to the building. Humanities buildings such as schools, cultural institutions and libraries. It is suitable to use split brick as the decorative material of the external wall. There are also many application cases of office buildings and residential buildings, which shows that the decorative effect of split bricks is generally favored by people.
Construction technology of external wall divided brick
First, the construction preparation
1, main materials and construction tools
Leppla wool series split brick, 42.5 ordinary portland cement, fine sand (screened), medium sand, JCTA-300A beneficial cement, cutting machine, sprayer, putty mixer, ash spoon, toothed clay board, ash board, iron trowel, guide rule, Mo Dou, silk thread, rubber sheet, sponge, jointing valve, cleaning cloth, etc.
2. The plastering quality of cement mortar at the grass-roots level meets the relevant requirements of Code for Quality Acceptance of Building Decoration Engineering (GB502 10-200 1). The surface of the base must be firm, free from brittle crack, crack or crust, and free from floating dust, oil pollution and adhesion particles. Check the flatness of the wall (flatness ≤4mm), and fill in large depressions or holes with cement mortar.
3, material requirements
1) cement: 42.5 ordinary portland cement is used, and the alkali content shall not be greater than 0.6%. There should be a factory certificate or re-inspection report, and the setting time, stability and compressive strength grade of cement should meet the requirements. Do not use cement or small pieces of cement with a factory date of more than 3 months.
2) Medium sand: used for plastering external wall cement mortar, with fineness modulus of 2.3 ~ 3.0, clean and free of impurities.
3) Fine sand: used for joint filling of divided bricks, the fineness modulus should be between 1.6 ~ 2.2, and the silt content should not be greater than 3%.
4) Brick splitting: The surface of the split brick shall be smooth, square and firm, and there shall be no defects such as missing edges, falling corners, dark marks and cracks. Bricks at the corner of Yin and Yang are cut to 45 degrees with a cutting machine. Split brick finished product size deviation is large, so bricks should be selected in advance, and packaged according to different length specifications, marked and packaged respectively, so as to prevent split brick-concrete packing with different specifications.
5) Beneficial cement: The tensile strength, shear strength, water resistance, temperature resistance, linear shrinkage and other indicators of beneficial cement should meet the requirements.
Second, the construction technology
1. Main requirements for leveling and plastering construction of external wall: plastering shall be carried out after 7 days after the completion of block masonry project and acceptance. Before plastering, basic treatment should be carried out, the surface of the block should be cleaned, and the mortar joints and holes on the wall should be filled. Masonry surface should be coated with special interface agent as adhesive layer, and plastered at intervals required by products. Before plastering, steel mesh should be set at the junction of different materials, corners of holes such as doors and windows, holes and grooves of buried pipelines, and places where the total thickness of plastering exceeds 35mm. The reinforcing mesh can be alkali-resistant glass fiber mesh or steel wire mesh. The width of the laid steel mesh shall not be less than 200mm, and the lap width with the matrix shall not be less than 100mm. When laying, use an iron trowel to wipe the cement mortar on the base, then flatten the steel mesh into the cement mortar and fix it with steel nails if necessary. Plastering shall be carried out in layers, and the thickness of plastering mortar shall be 5 ~ 8 mm each time, and a layer of plastering mortar shall be scraped after the final setting of the previous layer of plastering mortar. After the leveling mortar construction is completed, it shall be watered and maintained for not less than 3d.
2. Grass-roots treatment: The leveling layer shall be firmly bonded without crispness, pits, honeycomb and obvious protrusions, and the surface of the grass-roots layer shall be free of pollutants such as dust and oil stains, and shall be wetted with water. JCTA-300A beneficial cement dry powder is mixed with water into paste, and the water cement ratio is about 1:4. The stirred beneficial cement should be used up within 3 ~ 4 hours. Scrape off the beneficial cement on the surface of the base with a toothed mudboard, with a thickness of about 3mm, and spray water for curing for 3 days after drying.
3. Bullet measuring line: distinguish the size and color number of split bricks, determine the mortar joint spacing between bricks (generally about 8mm), and determine the paving design requirements such as I-shaped stickers and tic-tac-toe stickers. , and according to the pavement design requirements and the actual specifications of the brick, the grid line will pop up on the dry base. Different pavement designs can produce different decorative effects, and I-shaped stickers have the best effect. The method of I-shaped column is: firstly, measure the setting-out of the wall, set-out at the upper and lower ends of the wall, determine the position of brick arrangement at the bottom and top, then measure the distance between the upper and lower lines, and evenly arrange the bricks with the width and mortar joint as the spacing between the upper and lower lines. On the vertical center line of the wall, the length of the brick and mortar joint are evenly arranged on both sides as the left and right spacing of the brick.
4. Brick arrangement: Arrange bricks horizontally and vertically according to the details and the wall size to ensure that the gaps between bricks are uniform and meet the design requirements. Large walls, columns and stacks should pay attention to the whole brick arrangement, and try to avoid incomplete brick arrangement. Inevitably, the incomplete brick row should be arranged in a secondary position, such as the window wall or the internal corner, but attention should be paid to consistency and symmetry. When there are split bricks around the protruding part of the wall, the whole brick should be cut and matched with neat edges. It is not allowed to piece together the whole brick at will. On the whole wall, there should be no broken bricks below half a brick.
5. Wet water: Before paving, spray water on the wall with a sprayer to make water penetrate into the wall, so it is not suitable to hang water on the wall. Split brick doesn't need to soak in water.
6. Paving: Before tiling, ensure that the strength of the waterproof layer of the wall is above 70%. In order to keep the brick surface clean, the top-down paving sequence should be adhered to, and cement mortar should be plastered on the back of the brick with a gray spoon, leaving no gap at the bottom of the brick, but the cement mortar should be appropriate to avoid the overflow of cement mortar from polluting the brick surface and affecting the jointing operation. Then, according to the dividing line, the split bricks are built on the wall. Once the cement mortar overflows, it should be cleaned up with a clean cloth or sponge in time. Half a brick needed in the corner can be cut by a cutting machine, and the bricks in the inner corner and the corner can be butted with bricks cut at 45 degrees in advance.
7. Joint filling: spread cement mortar (fine sand: cement = 1:2) on the grey board, smooth it into a pulp sheet with a thickness of about 8mm (the selected width of the mortar joint), then divide it into 8mm×8mm strips with a mortar spoon, send it to the brick joint, and mark the joint with a jointing valve. Try to avoid sealing materials or cement mortar from polluting the brick surface. If it happens, immediately wipe it with a clean cloth or sponge dipped in wet water.
8. Tick joint: tick joint after caulking mortar is naturally air-dried. Brick joint effect has three kinds: concave circle, concave flat and flush with brick. Different brick joint designs can achieve different decorative effects. It is required that the jointing should be tight, not missing or higher than the brick surface, otherwise cement dialysis may appear in the brick joints in the future. This project adopts concave flat joint, and the joint depth is 3 ~ 4 mm away from the concave brick surface. Joints of parting bricks should be straight and smooth, joint filling should be continuous and dense, and the width and depth should be uniform. When jointing, if there is mortar scattered on the wall, don't clean it immediately. When the mortar is dry, scrape it off with a scraper. It is forbidden to use large-area plastering for jointing. Because of the rough surface of napped series split bricks, it is easy to cause brick surface pollution and difficult to clean when large-area plastering is used.
9. Cleaning the wall: check whether the mortar joint is cracked before cleaning, and repair it in time if there is any crack. After joint filling is completed 15 ~ 24h (depending on the weather at that time), after the pasted cement slurry has solidified to a certain strength, the brick surface shall be thoroughly scrubbed with clear water from top to bottom (it is particularly important to master the above time for the whole construction quality). Cleaning the wall with oxalic acid should be avoided, because improper cleaning with oxalic acid is prone to frosting.
Third, the construction matters needing attention
1, split bricks should be waterproof, moisture-proof and pollution-proof when stacked on the construction site. It is forbidden to mix cement, lime and other materials that may pollute the brick surface.
2. Brushed series products do not need to be stained with bricks before paving, thus reducing the pollution during construction.
3, paste and caulking cement slurry (mortar) should use low alkali cement, in case of cement pan alkali affect the decorative effect of brick surface, after the paste operation, bonding cement slurry dry before jointing operation.
4, brushed brick when the shop is stuck, brushed grain should be down.
5, should avoid the winter rainy season construction. In winter construction, it is forbidden to add antifreeze into cement slurry (mortar) for pasting and caulking.
6. Before paving a large area, make a model wall. After the sample wall is accepted according to the Code for Quality Acceptance of Building Decoration Engineering (GB502 10-200 1), large-scale construction can be carried out.
7, split brick paste must be firm, to test the bond strength of the sample block, the test method and result judgment should comply with the "Standard for Testing Bond Strength of Ceramic Tiles in Building Engineering" jgjgjg1/kloc-0-2008.
8, the whole construction process should try to avoid pollution of metope. After the construction is completed, effective measures should be taken to protect the finished products.
9. The quality requirements of the split brick paste are: the verticality of the facade is checked with a 2m ruler, and the deviation is not more than 3mm；; The surface flatness shall be checked by 2m guiding rule, and the deviation shall not be greater than 4mm；; Yin and Yang Angle founder with square check deviation is not more than 3 mm; Check the deviation of 5m line (less than 5m line), and the weld straightness is not more than 3mm；; The joint height difference and joint width deviation are not more than 65438 0 mm.