Terrazzo is a kind of cement-like artificial stone, which has physical properties and practical characteristics such as high density, high hardness, wear resistance, no dust and no peeling. With the rise of natural decorative building materials industry, natural marble and granite are often cleaned and polished, which are prone to pathological changes, but their gorgeous appearance can better reflect their commercial value, so they become the first choice for architectural decoration industry. The competitiveness of ordinary terrazzo market is decreasing day by day.
Reason for investigation:
1. Ordinary terrazzo can get better surface effect in a short time only by cleaning and surface waxing and polishing, and it should be adhered to every day.
2. Ordinary terrazzo is generally rough in construction.
3. Terrazzo is ignored by users because of its low price and lack of daily cleaning and maintenance, which leads to its rough and dirty surface.
4. The daily cleaning and waxing of terrazzo is complicated, difficult to operate and costly.
Nevertheless, terrazzo is still widely used in modern enterprises, factories, hospitals, schools, office buildings, exhibition halls, squares and other places because of its unique characteristics (wear resistance, good integrity, no peeling, economy and no dust). If a set of technology can be developed to make ordinary terrazzo as elegant, luxurious and crystal clear as marble, then the commercial value and market competitiveness of terrazzo can be greatly improved.
The terrazzo crystal floor is seamless as a whole, and the surface is smooth and textured. The finish is as high as 100 degree, the surface effect is high-grade, luxurious, individual and strong, and the overall installation appearance effect is no less than that of the marble engineering super board (800×800 large board).
Terrazzo crystal floor is anti-fouling and anti-skid. Because of the special production technology, the waterproof and antifouling of the floor has exceeded the requirements of the national standard. The improvement of surface anti-skid design will maximize the safety of stone use.
Terrazzo crystal floor has strong dustproof ability, which can meet the GMP environmental dustproof requirements of pharmaceutical enterprises.
Terrazzo crystal floor has high hardness and wear resistance, and it is easy to repair even if it is damaged under special circumstances. The wear resistance of the floor reaches or exceeds the level of granite.
Terrazzo crystal floor has no radiation, safety and environmental protection, which is the remarkable feature of crystal floor. You can enjoy luxurious and high-grade decoration, and there is no radiation danger. It can also be recycled repeatedly, effectively curbing human damage to the natural environment.
Terrazzo is black and white, cold and warm, and the color pattern is changeable, which provides endless imagination space for ground design.
Terrazzo is a commonly used building decoration material. Because of its rich raw materials, low price, good decorative effect and simple construction technology, it has been widely used. Terrazzo is also a kind of artificial stone, with cement as the cementing material and mixed with marble or granite crushed stones of different colors and sizes. After stirring, molding, curing, grinding and other processes, artificial stone with certain decorative effect is made.
1. The construction operation procedures are as follows
Leveling layer construction-fixing frame strips-plastering-polishing-waxing.
2. Key points of operation
(1) leveling layer construction
The construction technology of cement mortar leveling layer mainly controls the following problems.
A. grassroots cleaning. The empty drum of terrazzo floor is not firmly bonded, and many of them are caused by poor cleaning at the grass-roots level and sundries affecting bonding. Therefore, in the process arrangement, grass-roots cleaning should be completed as a process, that is, the next process cannot be carried out without grass-roots cleaning.
B the consistency of cement mortar should be appropriate, and the mixing should be uniform. The methods of on-site pile mixing, manual mixing and local sharing are not recommended. If there is a requirement of drainage slope, special attention should be paid to the direction of flooding and the position and elevation of floor drain, which should be completed accurately during leveling layer construction. The leveling layer is not serious, and it is wrong to go to the slope on the surface. In order to better control the drainage slope, if an inspection process can be added after the leveling layer is completed, and it is found that it is inappropriate and handled in time, the slope problem can be better solved. At the same time, it should be noted that while strengthening civil construction, it is necessary to cooperate with equipment work and solve the problems of time limit for a project and progress, elevation and protection of two types of work.
C pay attention to check the quality of the structure, such as cracks in the floor. If cracks are found, the relevant units should pay attention to them and make judgments and treatment opinions. In the terrazzo floor in recent years, cracks in the floor often affect the terrazzo surface (other surface layers will also encounter similar situations). Cracks that need to be treated are best treated before leveling layer construction. If the surface layer is finished, it will inevitably affect the color integrity of the surface layer and cause traces of connection. For floors with frequent running water, such as bathrooms and kitchens. Attention should also be paid to the wiping of floor drain and the plugging of floor holes, because once these parts leak water, they must be repaired. Repair will destroy the local surface, although it can be repaired, but the connection before and after construction is more obvious. Pay special attention to these problems before leveling. After the leveling layer is completed, water conservation will be carried out for 2 ~ 3 days after 24 hours, and surface construction can be carried out.
(2) Fix the frame rod
The existing terrazzo floor is inlaid with grid strips, which not only increases the beauty of the floor, but also facilitates the construction. Therefore, the existing terrazzo floor is provided with grid strips. When using the frame bar, the first thing to do is to play the line, and play the position of the frame bar on the leveling layer. The elastic line is mainly based on the design requirements for framing, combined with the plane size of the construction site, so as to be accurate and fully reflect the design intent. Some designs do not specify the size and direction of the border. Generally, 1 is used to determine the border size. 1m, it should be divided from the middle to both sides, and it should not be rushed to the corner. Sometimes it is necessary to consider the position of the door and the pattern and division of the ceiling, so that the division of the ground and the division of the ceiling echo each other.
Fix the door frame with plain cement slurry. On the door frame, fix it locally with plain cement slurry first, and then pull the line on the upper part for inspection. After being qualified, all of them are coated with splayed cement slurry. The height of cement slurry generally accounts for about 70% of the height of frame reinforcement, and the upper part should not be plastered with 3 ~ 4 mm As shown in the figure. This can make the ballast evenly distributed on both sides of the grating strip.
At the vertical and horizontal intersections of frame reinforcement, leave 4~5cm each, and do not apply plain cement slurry to avoid the phenomenon of sparse ballast. Before use, select the grid strips. If the corners are damaged, pay attention to the direction of use, so that the damaged surface faces down. Copper bars and aluminum bars that are not straight in bending should be straightened before use. Glass frames are easily broken and damaged, so be careful. All kinds of materials should pay attention to the neat edges and corners at both ends of the frame reinforcement to avoid obvious connection at the splicing place.
After the frame is fixed, attention should be paid to protection and proper water conservation. For the misplaced frame reinforcement, it should be replaced in time. Fix the frame rod as shown in the following figure.
(3) Gypsum
The frame is fixed for about three days, and when the frame is stable, it can be plastered, commonly known as loading ash.
First of all, the leveling layer should be cleaned up, and the floating ash or broken frame bars should be cleaned up. In order to make the surface mortar and leveling layer firmly bonded, the leveling layer should be wetted before plastering, and then a plain cement slurry should be brushed. Plastering layer should be from the inside out. After filling in a piece, pat it gently with an iron trowel and then smooth it out. Finally, put a small ruler on both sides of the frame, check the flatness and elevation, and finally roll it with a roller.
If the local height is too high, use an iron trowel to dig out the excess part, and then pat the dug part flat. Don't use scraping bar to scrape it flat, because it is easy to cause uneven distribution of ballast, or less local ballast, resulting in overall disunity. Slap with a trowel with moderate force to make the surface smooth and the ballast stable. Surface plastering should be higher than the grid 1 ~ 2mm. After polishing, the surface layer can be consistent with the grid strips.
If you use artistic terrazzo, you should finish the surface mortar of the same color first, and then make another color to avoid mixing or color difference. On the same ground, the surface with different shades should be paved with dark parts first, and then with light parts. The mixing amount of topcoat and ballast with different specifications and colors shall be handled by special personnel. In particular, the amount of pigment added should be strictly measured. Mix the pigment into cement, dry mix it evenly first, and then mix the washed ballast with cement. The consistency of cement ballast slurry is about 6cm. Before large-scale construction, samples should be made, and large-scale development can only be carried out after the design is confirmed.
The proportion of cement stone slag slurry on the surface layer is slightly different due to the different particle size of stone slag, and it can also be different due to the different requirements of decorative effect. The commonly used ratio is: cement: ballast = 1: 1.5 ~ 2 (volume ratio). In order to obtain dense ballast on the surface and increase the appearance, you can also spread a layer of ballast on the flattened surface and flatten it to make it stable. However, it should be noted that the ballast should be evenly dispersed and the quantity should be appropriate.
(4) polishing
Polishing is an important process for terrazzo effect. The main purpose of grinding is to grind off the cement slurry on the surface and smooth the ballast on the surface.
There are two kinds of polishing: mechanical polishing and manual polishing. If the construction conditions permit, try to use mechanical grinding as much as possible, which not only has fast work efficiency, but also reduces the labor intensity. If a grinder is used for polishing, a grinding tool is usually used. The structure of abrasive tools generally includes abrasive particles, binders, pores and fillers.
Abrasive particles are the main body of abrasive tools, and the exposed edges and corners on the surface of abrasive tools are used as cutting edges for cutting terrazzo. There are many kinds of abrasives, such as quartz sand, corundum, natural diamond and cemented carbide. According to different uses, abrasives are processed into particles with different material diameters. According to China standard GB 2477-81+0, abrasive particle size is divided into four categories, numbered 3 1, and the specific classification is shown in the following table.
Grinding? Grain? Grinding? Powder? Micro? Powder? fines
12#、 14#、 16#24#、36#、46#60#、70#、80#? 100#、 120#、 150# 180#、240#、280#? W63、W50、W40W28、W20、W 14W 10、W7、W5？ W3.5、W2.5W 1.0、W0.5
Binder is the bonding material of abrasive tools, which can consolidate abrasive particles and make them into abrasive tools with certain shape and strength.
Pore is the gap inside the grinding tool, which can exclude grinding and can accommodate cooling water when grinding. Because the rough grinding of terrazzo discharges a lot of debris, if the abrasive structure is compact, there is a small place to accommodate abrasive debris and cooling water, which will not only burn the plate, but also affect the gloss of the plate. Therefore, in order to overcome this phenomenon, a part of soft materials, such as aerated concrete or perlite particles, are generally added to the abrasive structure.
Polishing mainly controls two points, one is to control the polishing time; The second is to master the number of polishing. If the grinding start time is not well mastered, it will affect the work efficiency and quality. If grinding starts too early, the strength of cement ballast slurry is too low, and the ballast will loosen or even fall off. If the grinding time is late, the strength of cement slurry will be high, which will bring difficulties to grinding. It takes longer to achieve the same effect.
Different cement grades, different proportions and different temperatures will affect the hardening and strength growth of cement ballast slurry. The best way to get the appropriate grinding start time is to determine it after trial grinding. The general principle is not to lose slag when grinding. The following table is the reference time of grinding start time at different temperatures.
Way? Temperature (℃)
5~ 10? 10~20? 20~30
Mechanical polishing (d) manual polishing (d)? 5~62~3? 3~4 1.5~2.5? 2~3 1~2
Note: Days are counted from the completion of terrazzo compaction and finishing.
Different grades of terrazzo floor have different polishing times. Generally, the ordinary terrazzo made now has to go through "two pulps and three grinds" to achieve the ideal effect. High-grade art terrazzo should increase the grinding times appropriately to improve the fineness of oilstone. Usually, a thicker grinding wheel is used for the first polishing, generally 60 ~ 80. This time, it is required to polish smoothly and evenly, so that all stones and frames can be clearly exposed. After the first polishing, put off the turbid slurry, rinse the surface with clear water, and then check the surface flatness with a guide rule. The first time, due to the roughness of the grinding wheel, the surface has a certain degree of wear marks. In addition, surface defects, such as sand holes, small holes and bubbles, are exposed by grinding off a layer of cement slurry. These surface defects should be wiped on the same surface with cement slurry of the same color, commonly known as grouting. After curing for 2 ~ 3 days, the second grinding can be carried out.
The grinding wheel thinner than the first one should be selected for the second polishing, and the polishing method is the same as the first one. This time, it is necessary to remove the wear marks and polish the surface. For local pits and small defects, repair with cement slurry of the same color, maintain for 2 ~ 3 days, and then polish for the third time.
Use 180 ~ 240 fine grinding stone for the third time. This time, the surface should be smooth and level, there should be no sand holes and air holes, and the stones should be evenly exposed. Due to poor mechanical control, the corners should be properly polished by hand and finally rinsed with water.
(5) Waxing
The purpose of waxing is to make the terrazzo floor brighter, smoother and more beautiful. At the same time, because the surface has a thin layer of wax, it is easy to maintain and clean. Waxing can only be started after the surface layer is completely dry. Before waxing, in order to better combine the wax solution with the surface layer, the surface layer should be scrubbed with oxalic acid. The function of wiping oxalic acid is mainly to clean up the residual cement slurry and fine stone powder on the surface, so that a small amount of suspended slurry and powdery substances deposited on the surface can be eliminated under the action of oxalic acid. Oxalic acid, namely oxalic acid, with the chemical formula of (COOH)2, is the simplest dicarboxylic acid. Colorless crystal, soluble in water. Oxalic acid easily reacts with calcium hydroxide in cement, and has slight corrosion and decontamination effect on the surface. Therefore, scrubbing with oxalic acid before waxing can ensure the adhesion between the wax liquid and the surface layer and improve the wax finding effect.
When oxalic acid is used, it is dissolved into 10% oxalic acid solution with water, evenly sprinkled on the surface, lightly ground with oilstone, washed with water, and waxed after the ground is dry.
Waxing, also known as wiping wax, generally uses floor wax, which is a kind of wax product to protect and decorate the ground. It is made of natural wax or solid paraffin extracted from petroleum and solvent. You can also use Sichuan insect wax 1 kg, kerosene 4 kg, put it in an iron drum 130℃ and boil it (emit white smoke), add six taels of rosin water (No.200 solvent gasoline) and one or two fish oils to make it.
Waxing is commonly used in the following two ways. One is to dip cotton yarn (or thin cloth) in the finished wax and rub a layer on the surface. After drying, tie a sack (or hemp) roll with a stone mill and rub it a few times until it is smooth and bright. Another waxing method is to put the finished wax on the surface layer, bake it with a blowtorch, so that the melted wax liquid penetrates into pores, and then polish it.
Waxing ground should be bright and smooth, with smooth and delicate surface, clear and beautiful stones and even colors. If there is dust locally, you can gently wipe it with a mop dipped in a small amount of kerosene.
3. Common quality defects in engineering and their prevention
(1) Empty drum on the ground
Compared with other types of ground, the hollowing of terrazzo floor is more serious. The reason for this situation is that there are many floors of terrazzo floor, different time and materials, and improper handling may affect the bonding and lead to empty drum. Empty drum is mainly manifested in: a. The surface layer and the base layer are not firmly bonded, resulting in empty drum. B. The surface layer is not firmly bonded to the leveling layer, resulting in empty drum.
The main reason is that the basic level is not cleaned up enough, such as additives such as ash and residue, which will affect the bonding between the two layers. In addition, the lack of careful scanning of the combination layer of plain pulp is also the cause of empty drum. It can be seen that the cleanliness of the base is the key factor affecting the bonding.
Surface hollows need to be treated, especially those with cracks in a large area, which will greatly affect the service life. But for the existing terrazzo floor, when dealing with the problem of empty drum, we should pay attention to the color of the repaired floor as much as possible, which is consistent with the original color. When repairing, try to make the size of the repaired piece regular. If the whole piece can be repaired, the effect will be better.
(2) Uneven stone exposure
Essentially, it reflects the problem of ground flatness. Especially when there are footprints on the surface, if not handled in time, it is bound to sink slightly at the footprint. In addition, if you step on a soft surface, the stone at the footprint will sink and the upper part of the cement slurry will increase. When polishing, slight subsidence at the footprint will affect polishing. So it seems that the stones on the surface are not uniform and clear enough.
This phenomenon is mainly because the operator should arrange the construction procedure reasonably and try to avoid a large number of interspersed on the smoothed surface. In addition, try to wear flat-bottomed rubber shoes during construction, and don't wear high heels or rubber shoes with obvious concave and convex bottoms.
(3) Uneven grating exposure
Grid strips have a certain decorative effect. If the grid strips are intermittent, it will affect the decorative effect of the ground. The main reason for uneven exposure of grid strips is uneven surface. Because the cement slurry on the surface layer covers the grid strips, it may not be ground during grinding, resulting in blockage. It is also possible that the cement slurry is too thick and worn off during polishing, so there is still a small amount of cement slurry covering the grid strips to cover it.
In addition, the elevation of the frame is inconsistent, which has its own high and low, so when loading ash, it is bound to cause too many frames in individual parts to be covered. This kind of problem is mainly to control the elevation of the upper part of the mast, check the cable when installing the mast, and correct the mistakes in time when they are found.
(4) The color of terrazzo is uneven
Commonly known as "painted face", there are two main reasons for this defect. First, the pigments are not mixed evenly. Its second surface is polluted by other colored liquids. Pigment mixing should be handled by a special person, and the measurement should be accurate. Can't be evaluated visually. In addition, you can't pour paint while adding water. Doing so will lead to pigment caking and local color deviation. We should adhere to the method of adding water and ballast after the pigment and cement are mixed evenly to make the pigment disperse evenly.
The surface layer is polluted and should be cleaned up in time. The most fundamental way is to strengthen management. If the ground hedge work is completed and other projects are still under cross-construction, it is best to lay a protective material on the upper surface to avoid pollution and damage. For advanced art terrazzo, special attention should be paid to this aspect.
4. Repair and polishing of old terrazzo floor
Repairing and polishing terrazzo floor is a relatively simple construction method, but it is not easy to really make the repaired and polished terrazzo floor feel brand-new.
According to our experience in the construction practice of modern protective buildings, the key to terrazzo floor reconstruction is not polishing, but repairing. Even if there is no crack on the floor, the repaired cracked surface should have no or little color difference with the surrounding ground.
(1) operating procedures
Crack repair-mechanical polishing-complementary color treatment-coating protective agent
(2) Key points of operation
Crack repair
A analyze the cement, cement label and stone size range of the original terrazzo floor.
B choose the same cement as the original terrace and stones with very close particle size.
C, expanding the crack according to the natural trend of the crack.
D, mixing the selected cement and stones according to their gradation.
E, caulking the mixed terrazzo raw materials. The gap should be cleaned, and then coated with concrete interface agent to ensure that the new material is firmly bonded with the original floor.
mechanical polishing
A. Before mechanical polishing, it must be confirmed that all cracks have been processed and the newly embedded terrazzo has been solidified firmly and has considerable strength.
B the grinding disc shall be polished layer by layer with 600-mesh high-grade oilstone.
C. After grinding once, check the grinding effect, and then replace the oilstone with higher mesh for finer grinding according to the situation.
D. Carefully polish the repaired crack, and carefully check whether the joint is smooth, and then stop polishing.
E in the inner corner, the portable small mill must be replaced for grinding.
Complementary color treatment
A. after mechanical polishing, cleaning with oxalic acid.
B carefully check the crack repair, mainly observe the color difference of the floor finish.
C. If the color difference is large, please ask professionals to repair the color matching to reduce the color difference.
Coating protective agent
A. There should be no dust on the floor before the protective agent is applied.
B. Stone protective agent shall be painted evenly, and shall not be missed.