1. Introduction
Egyptian beige stone often encounters some special problems in paving construction and daily use, and it is quite difficult to solve them. For example, “long hair”, “black spots”, “sunken lines”, etc. The most serious phenomenon is the occurrence of large-scale debris collapse (most of these phenomena occur in wet installation of the ground and wall areas, as well as on floors with underfloor heating). To address this common lesion, this article attempts to explore the causes, prevention methods, and treatment techniques of the lesion from the perspectives of petrology, chemistry, and stone application care, for your reference.
Egyptian beige marble
Physical properties: compressive strength 18300PSI, bending resistance 1300PSI, water absorption 0.12%
Board characteristics: The Egyptian beige glossy large board presents a beige background color, divided into various colors, including tofu flowers, uniform dots, and crystal lines.
2. The cause of the lesion
From a petrological perspective, Egyptian beige stone belongs to carbonate rocks deposited in the ancient Mediterranean. During the process of sedimentation and diagenesis, due to pressure dissolution, i.e. under the static pressure of the overlying rock layer, the rock layer undergoes uneven dissolution, and certain substances accumulate to form a structural plane, which is called a suture line on the profile. This structural plane presents a serrated curve in the profile, resembling a joint seam in an animal skull; On a flat surface, it is an undulating and uneven surface. The main components that make up the suture are organic matter, iron, manganese, and marl.
The most prominent feature of sutures is that their composition is completely different from the rock composition on both sides of the line. The shape and width of sutures are directly related to the sedimentary environment. The shape of sutures varies with the changes in rock layers, with some shaped like serrations, others forming large bends, and the total body being a straight line.
Due to differences in composition, the stitching fastness between the suture and limestone is also different, with organic matter having the worst bonding fastness, iron and manganese components having stronger bonding, followed by muddy limestone components. Although it is a suture, it is not a component of the original rock, and its structural plane is still the weakest part. The processed board is most prone to fracture at the suture line. Sometimes, although the fracture does not connect, channels of foreign materials have been formed.
When processing Egyptian beige stone, vertical cutting will form parallel patterns, such as “silver line beige”, “gold line beige”, and “red line beige”; Cutting along the horizontal plane will form cloud-like or irregular circular patterns, such as “magnificent and magnificent”. When cutting vertically, due to the parallel development of patterns between the suture line and the sedimentary layer, the natural defects of the stone towards the suture line are covered up, and there is rarely a problem of debris collapse; When cutting parallel layers, irregular circular patterns of stitching lines will be formed on the board surface. The vivid and rich patterns are deeply loved by people, but defects can also be exposed. The main problems are the occurrence of dents, warps, and debris in the suture area, as well as the discoloration and alkalinity of the sliding suture.
From the perspective of stone application chemistry, if Egyptian beige stone is not affected by moisture, does not come into contact with salt alkali, has no strong external force, and has no significant temperature changes, the above problems generally do not occur. The vivid, elegant, and bright decorative characteristics of stone can be fully expressed. However, if cement mortar is used for wet paving, installed on sanitary walls or floors, or installed on the bottom with heating facilities, the above problems will occur.
