Egyptian beige stone often has some special problems in paving construction and daily use, and it is quite difficult to solve. For example: "long hair" (needle crystals), "black spots", "streaks in the line", etc., the most serious is the occurrence of large-scale collapse (most of these phenomena occur in a multi-water environment, wet installation The ground and wall parts, and the floor with floor heating are also serious.) In order to solve this common disease, this paper attempts to make some preliminary investigations on the causes, prevention methods and treatment techniques of the lesions from petrology, chemistry and stone application nursing for reference in the industry. Cause of the lesion From the perspective of petrology, the Egyptian beige stone belongs to the carbonate rock of the ancient Mediterranean. During the sedimentary diagenesis, due to the pressure dissolution, that is, under the static pressure of the overlying strata, the rock layer is unevenly dissolved, and some materials are rich. The set forms a structural face, which is called a suture. This tectonic plane has a zigzag curve in the cross-section, such as a joint seam in the skull of the animal; on the plane is a undulating surface. The main constituents that make up the suture are organic matter (also known as asphaltenes), iron, manganese, and marl. The most striking feature of the suture is that its composition is completely different from the rock composition on both sides of the line. The shape and width of the suture are directly related to the sedimentary environment. The shape of the suture changes with the change of the rock layer, and some shapes are like jagged. Some also form a large curve, and the whole is a straight line. Due to the different composition, the suture (bonding) fastness of suture and limestone is also different. The bonding fastness of organic matter is the worst, the iron and manganese components are cemented strongly, and the marl content is second. Although it is stitched (bonded), it is not a component of the original rock, and its structural surface is the weakest part. The processed sheet is most likely to break at the suture. Sometimes, although the fracture is not penetrated, a passage of foreign matter has been formed. When processing Egyptian beige stone, the vertical layer cut will form a parallel pattern, such as "silver line beige", "golden line beige" and "red line beige"; cutting along the level will form a cloud-like or irregular ring pattern. Such as "golden brilliant." When the vertical layer is cut, the natural defects of the stone to the suture are masked due to the parallel development of the suture and the deposited layer, and the problem of collapse is rare; when the parallel layer is cut, irregular stitching is formed on the surface. The circular pattern of the line. The vivid and rich patterns are deeply loved by people, but the defects are also exposed. The main problem is the appearance of depressions, lifts, collapses, and discoloration and efflorescence of the sutures in the sutures. From the point of view of stone application chemistry, if the Egyptian beige stone is not affected by moisture, it does not touch the salt and alkali, there is no strong external force, no large temperature change, generally the above problems will not occur, the stone is vivid and elegant. And the bright decorative features can be fully expressed. However, if the cement mortar is wet-laid, installed on a hygienic wall or floor, or installed on the bottom of a heating facility floor, etc., the above problem occurs. Exploring its causes mainly comes from three aspects: one is the natural defects of suture construction, the other is excessive water and saline, and the third is that the heat and cold change too fast. Salt and alkali formation analysis of crystals (commonly known as long hair): The suture line of Egyptian beige stone is the weakest part of the stone, especially the suture of organic matter and marl. The material structure in the suture is relatively loose and strong in water permeability, and it is easy to become a channel for water migration and evaporation. The suture is actually a structural surface, and can also be regarded as a natural gap of stone. Soluble salts and alkali substances in cement mortar and other building materials will migrate to the surface of the stone with moisture, and a white crystalline substance will form at the gap after evaporation of water. The precipitated crystalline material not only destroys the aesthetic appearance of the stone, but also the crystallization stress tends to swell and expand the stone gap and the pores, causing the surface of the stone to flake off or powdery. It is more common when the Egyptian beige is installed on the bathroom floor or wall. The saline-alkali substance is sourced from both the interior of the wall and the air in the bathroom and the contaminated liquid. Enrichment and pollution of foreign substances (commonly known as dark spots): The organic matter and the marl content in the suture are high in porosity and water absorption, and the strength is much lower than that of the carbonate component. A linear depression is formed along the suture line on the surface of the stone, and a pit is formed locally. The depressions cause the enrichment of foreign pollutants and also cause biological reproduction. Enriched pollutants contain dust and humus from human life, diet and human activities, as well as animal hair metabolism, dander, etc., which will breed a large number of microorganisms, such as enzymes, over time. The color of the material in the depression changes or even darkens. The discoloration phenomenon formed by this kind of pollution is very different from the color and material composition of the suture itself, and has a great influence on the appearance of the stone. Collapse: Natural stone itself is a kind of rigid material with a certain water absorption rate, which will cause thermal expansion and contraction and freezing and thawing when the temperature changes. As mentioned above, the strength of the material of the Egyptian beige stone in the suture is lower than that of the other major carbonate components of the rock. Once the stone is subjected to the stress, it is easy to cause stress damage at the suture site. Most of the rock is cross-contact, and the contact surface cannot be a straight flush surface with a certain angle or even an acute angle contact. The upper part of the rock with an acute angle has a wedge-shaped tip that is subjected to an external force (the hard sole will have a large effect on the pedaling), and it is easy to break the rock itself, causing a "crash" phenomenon. When the stone is installed in the part with the geothermal pipeline, the thermal contact will cause the thermal expansion and deformation of the stone, and the suture will change from closed to open state, or it will be repeated with alternating heat and cold. Frequent deformation will inevitably lead to structural changes, the suture will completely become a through gap, the rock on both sides of the suture is in a suspended state, and it is more prone to widespread "cracking" shedding. Linear depression: As mentioned above, the linear depression mainly develops along the suture. The reason is that it is composed of many aspects. It has the material itself and the result of external stress. It is often after the hard care or grinding of the Egyptian beige stone. It will be found that the crystal hard care film has a more pronounced depression along the suture. The reasons for the occurrence are as follows: the hardness of the suture material is low, and it is easy to be polished away; the acute angle of the edge is relatively strong, and the abrasion amount is relatively large; the acidic crystal hardener has strong permeability to the carbonate stone and is more likely to penetrate. Inside the suture, the suture portion requires more crystalline hard material than other parts. Therefore, after the crystal hard treatment, the protective film formed thereof changes with the substrate. Prevention of lesions Through the above analysis of Egyptian beige stone, it should cause design, construction and nursing to pay attention to the lesions easily caused by Egyptian beige stone, and take corresponding preventive measures to minimize or avoid the occurrence of lesions. Material selection: For wet, multi-water environments, or environments where the hot and cold pipes are alternately changing, it is not suitable to use marble materials with suture construction. Stone types with less sutures and uniform structure should be selected. Control of saline and alkali: If the stone is to be paved on the ground with suture structure, the amount of water should be reduced as much as possible. Especially for the ground heating method, the bottom layer of cement should be fully dried, then the stone paving should be carried out, and the stone should be strictly controlled. The water content of the underlying material. Stone protection: the correct choice of stone protective agent, effectively reduce the water absorption rate of the stone; when using the wet paste method to paving the ground, it must be superimposed with a stone bottom protective agent that has a sealing effect and does not reduce the cement adhesion. The protection of the stone should be reasonable. The protection of the back of the stone is heavier than the surface. The water repellency and sealing should be taken into consideration. The water-based protective agent should not be used on the front side. The solvent-based protective agent with good permeability should be selected. When the surface protective layer reaches 3~ When it is more than 5mm, it will greatly reduce the occurrence of stone lesions. The grounding heating method should have higher requirements for the protective agent. When applying the protective agent, try to make the protective agent penetrate into the deep layer of the stone. The protective agent should be carefully applied on both sides, and the double layer must be double-layered on the bottom surface. The practice is to apply a special protective agent for the sealed bottom surface after applying the osmotic protective agent to minimize the capillary inhalation and precipitation crystallization of the saline-alkali water. Treatment of lesions Intensive treatment: The intensive care of Egyptian beige stone is best in the processing stage. It is best to use the adhesive pressure infiltration method to make the binder penetrate into the suture and micro-crack of the stone to achieve a firm bonding effect. . The stone produced in this way maintains the pattern of the stone itself, and strengthens the strength of the stone around the suture to make up for the weakness of the stone. Glue refurbishment: When there is a collapse in the paved ground, it must be fully replenished and resin-filled after the stone bottom is fully dried and collapsed. When filling, pay attention to clean the surface of the collapse, not contaminants, water, dust, etc., so as to avoid the bond is not firmly collapsed again; the preparation of the resin glue should be targeted, both the adhesion and the hardness after curing Also take care of the color, it is best not to use the toner to adjust the glue, so as not to affect the bonding effect. After refurbishment, wait for the stone to be completely dry, and then do a good penetration protection, which will help to avoid the collapse again in the future. Similarly, before doing crystal hard care and grinding, it should also be used to repair the suture sag and collapse, and then grind and level the crystal before hardening, so as to avoid the linear depression after crystal hard care. Head Lamp,Led Headlamp,Head Torch Light,Hard Hat Light Hangzhou Fantasy Technology Co.,ltd , https://www.ledluxlite.com
Causes and treatment of Egyptian beige stone disease