Ministry of Housing and Urban-Rural Development: Manual excavation for foundation piles to be restricted!

Is the cement mortar bonding process for decorative tiles the same as installing tiles on exterior walls? If it’s not attached properly, it can fall off and hurt people

I don’t understand why there are restrictions on the hot-melting process for asphalt-based waterproofing membranes

The use of the following construction methods, equipment, and materials is prohibited: 1. The on-site method of fabricating simple reinforcement cover spacers; 2. The method of using winches to straighten rebar; 3. Bamboo (wood) scaffolding (prohibited); 4. The use of full-scale steel pipe support frames (prohibited); 5. Alkali-based rapid-setting agents. These methods are prohibited – it’s not clear what methods can be used as alternatives

Process flow: 1. In-depth design for decorative tile work； 2. Substrate preparation ； 3. Hang vertically, set square, check alignment, apply plaster guides ； 4. Apply the undercoat and leveling layer ； 5. Laying bricks, dividing sections, marking lines ； 6. Application of facing tiles and grouting ； 7. Clean the surface ； 8. Tensile test. Construction steps: 1. In-depth design for decorative tiles: Before construction, auxiliary in-depth design is carried out for the details that are not specified in the design. Determine the arrangement of the decorative tiles, joint width, joint depth, grouting method, and color, etc. Common arrangements for decorative tiles include jointed alignment and offset alignment, etc. Joint filling methods typically include full filling, partial filling, and open joints, while the shapes of the joints can be concave or flat. Expansion joints should be provided when installing exterior wall cladding tiles, and these joints should be filled with flexible waterproof materials. Vertical expansion joints can be installed on either side of the opening or at positions corresponding to transverse walls and columns, while horizontal expansion joints can be placed above, below the opening, or at positions corresponding to different floors. The decorative tiles applied to both sides of a wall’s deformation joint should have a gap between them that is not narrower than the width of the deformation joint itself. 2. Substrate preparation: Before applying the plaster base coat, it is necessary to prepare the substrate. For concrete substrates, roughen the surface first and then clean it thoroughly with a wire brush, or use a mixture of cement and fine sand along with A09 high-strength mortar additive to create a rough texture on the surface. For brick-based substrates, the remaining mortar on the wall surface must be cleaned thoroughly. For substrates such as aerated concrete, concrete hollow blocks, and fiber cement boards, after cleaning, repairing, and applying polymer-cement mortar, a layer of metal mesh should be laid to enhance the adhesion between the substrate, the leveling layer, and the bonding layer. 3. Ensure verticality, set right angles, mark guidelines, and apply plaster test pieces: Use a theodolite to draw vertical lines at the corners of buildings, around doors and windows, as well as at other vertical elements, using these lines as vertical reference points. For horizontal alignment, use a laser level to establish horizontal references. The goal is to minimize the amount of plaster needed for wall repairs, so test pieces are applied in layers at various points. According to the gray cake reinforcement requirements, the spacing should not exceed 2 meters ； At the right-angled corners, straighten both sides ； At the same time, it is important to ensure that the slope of the water flow and the drip lines for finishes such as parapet tops, window sills, eaves, moldings, and canopies are properly designed. 4. Apply the underlayment mortar for leveling: First, moisten the surface of the base layer and apply a coat of bonding mortar. Then, apply the mortar layer by layer; at normal temperatures, a cement mortar ratio of 1:3 or 1:2.5 can be used, with the proportion of cement possibly increased as appropriate. The thickness of each layer of mortar should be controlled between 5 and 7 millimeters. Use a wooden trowel to smooth it out, and once it has set, wait until it is about 60–70% dry before applying the second layer ； Level it with an aluminum trowel, roughen the surface with a wooden trowel, and then water it for curing after it has reached final setting ； The thickness of the leveling layer should be kept at around 20 millimeters; measured with a 2-meter straightedge, the maximum allowable deviation in the flatness of the leveling layer’s surface is 4 millimeters, while the maximum allowable deviation in its verticality is 5 millimeters. 5. Brick laying, partitioning, and marking lines: Wait until the leveling layer is 60–70% dry before installing the exterior wall tiles. Before that, a construction layout should be prepared; control lines should be marked on the leveling layer in segments according to the actual height. The number of exterior wall tile units should be calculated so that an even number of tiles lies between the two lines. However, note that there should not be more than one row of non-standard tiles on the same wall, and they should be installed in less visible areas. 6. Application of decorative tiles and filling of gaps: (1) Material preparation: exterior wall tiles, \"Vinyl\" two-in-one adhesive, water, etc. (2) Tool preparation: appropriate containers, electric mixer, trowel, toothed trowel, rubber scraper, cleaning sponge, level, etc. (3) Sealing with adhesive for connected decorative tiles ① Surface inspection: The surface should be clean, solid, and flat, free of oil, wax residues, release agents, or any other loose materials. The strength and flatness at the base level shall meet the requirements of **relevant specifications. The sun-exposed surface should be watered to cool it down, so that it reaches a state where it is dry on the outside but still moist on the inside. ②Mixing the paste: Choose an appropriate container, add water and the \"Venier\" all-in-one tile adhesive in a ratio of 6.5:25, adding water first followed by the powder, then use an electric mixer to stir thoroughly until a paste-free, uniform mixture is obtained. Let it sit for 10 minutes, stir it again, and then use it. ③Gluing and sealing: The exterior wall cladding tiles should be installed from top to bottom. First, draw a horizontal reference line on the base surface, and then draw the corresponding horizontal and vertical lines according to the paving design requirements. Use a trowel to apply the prepared mortar to the base surface, applying about 1 square meter at a time (depending on weather and temperature), with a thickness of around 1 millimeter. Use the trowel to spread the prepared mortar on the back side of the decorative tiles, ensuring that the gaps between the tiles are filled completely. Apply the decorative tiles to the wall along the grid lines, then gently tap the surface of the tiles with a flat wooden trowel to ensure they are firmly and evenly attached. Randomly select a tile and visually inspect the adhesive coverage on the back of the tile; the adhesive coverage should be over 90%. The grout gaps between the connected decorative tiles and bricks must be filled with grout promptly, and compacted using a rubber trowel. Within 20 minutes after the tile installation, the position of the tiles and the width of the joints can be adjusted, and a level can be used to check the flatness and verticality of the tiled surface. (4) Removing the adhesive from the decorative tiles: After 30 minutes, thoroughly wet the adhesive on the surface of the tiles using a sponge. After 3 minutes, peel off the adhesive along its edges in a diagonal direction. Then use a joint compression tool to compress the area around the joint, creating either a recessed or flat joint. 7. Cleaning the brick surface: About 15 minutes after the grouting is completed, use a damp sponge that has been squeezed out well to carry out the first preliminary cleaning of the brick surface, wiping in the same direction. It is important to avoid waiting too long, as this will cause the grout to harden and make cleaning more difficult. Since water can affect the effectiveness of dark-colored grout, the sponge should be as dry as possible during the initial cleaning. Approximately 24 hours later, the brick surface should be thoroughly cleaned a second time with clean water until it is completely clean. Before dismantling the structure, perform a final thorough cleaning of the entire exterior wall until it is completely clean. It is particularly important to note here that since sealants are alkaline materials, acids can cause severe corrosion to them; therefore, the use of hydrochloric acid, sulfuric acid, or nitric acid is prohibited during cleaning. 8. Pull-out test: After the installation of exterior wall tiles is completed, it is necessary to examine the adhesion strength of these tiles. According to the \"Standards for Testing the Adhesion Strength of Tiles Used in Building Construction,\" a pull-out test can be conducted 14 days after the tiles have been installed on the exterior walls. Precautions: 1. Construction should not be carried out in conditions with standing water, during rain, snow, frost, or when wind speeds are above level 6. Additionally, the adhesive may develop efflorescence if it is exposed to rain before it has fully dried (approximately 24 hours) after construction is completed ； 2. Wipe away the dust on the back of the tiles with a damp cloth before pasting ； 3. Use cross-shaped adhesive particles to ensure that the gaps are vertical, even, and of uniform size ； 4. Before it dries, the finish can be cleaned with a slightly damp sponge or cloth ； 5. Do not step on the surface or carry out grouting until 24 hours have passed since laying it ； 6. On-site inspection shall be conducted 14 days after the completion of construction, based on a period of 56 days ； 7. Never add water to dried glue paste and try to use it again ； 8. This product contains cement, which reacts alkalinely when in contact with water; proper protection for the eyes and skin is necessary. If glue gets on the skin, it can be cleaned off with water. If it gets into the eyes, seek medical attention immediately.

It is composed of components such as vertical posts, horizontal bars, diagonal braces, and adjustable base supports. The vertical poles are connected using sleeve insertion joints, while the horizontal and diagonal braces are connected to the vertical poles through the ends of the rods and joints that fit into the connection sockets; these connections are secured with wedge-shaped pins. Wall connection points are installed as specified to create a geometrically stable structural system. Metal sheets with hanging clips are laid on top of this structure, and safety nets are attached on the outside for external protection and decoration during construction.

Manually dug piles are generally not used in design; under the same conditions, their cost is higher than that of other types of piles. It’s just a renovation project; the site is too small or there aren’t enough piles, so manual bored piles are used as a solution