Discussion on the properties and applications of ceramsite concrete

A brief discussion on the characteristics and applications of lightweight ceramsite concrete hollow blocks. With the further development of wall material reforms, new types of wall materials are gaining increasing recognition from the construction industry and various sectors of society due to their superior material properties and positive overall social benefits, and they are being widely used in both industrial and residential buildings. The lightweight ceramsite concrete hollow blocks developed in Linyi area of Shandong Province by utilizing the latest domestic technologies offer significant advantages over traditional wall materials such as ordinary fired solid bricks. 　　I. Buildings with good thermal insulation performance achieve high overall energy-saving benefits in heating. When the building structure remains identical and only the wall materials are changed, calculations show that aerated concrete hollow blocks result in approximately 30% greater energy savings compared to buildings made of ordinary fired solid bricks. Experiments show that the thermal resistance of walls constructed with 190-mm-thick ceramsite concrete hollow blocks is greater than that of walls built with ordinary fired solid bricks with a thickness of 370 mm. Therefore, aerated concrete hollow blocks offer significant advantages in terms of heat reduction and insulation in summer, heating and warmth retention in winter, as well as reducing noise pollution. 　　II. Reducing project costs 　　Due to the improved properties of various materials used in ceramsite concrete hollow blocks, it is possible to reduce the thickness of interior and exterior walls. The exterior wall thickness can be reduced from 370 millimeters to 240 millimeters, and the interior wall thickness can be reduced from 240 millimeters to 190 millimeters, thereby reducing the project cost. Furthermore, since the volume of ceramsite concrete hollow blocks is only about 1/3 that of ordinary fired solid bricks, and coupled with the thinning of the wall walls, the total weight of the building’s walls is reduced. As a result, it is possible to reduce the cross-sectional areas of beams, columns, and foundation structures in the structural design, thereby lowering the project cost. By using these blocks, the construction period is shortened, labor consumption is reduced, thereby naturally lowering the project cost. When constructing interior and exterior walls using ceramsite concrete hollow blocks, the labor requirement per square meter of effective area is reduced by more than 30% compared to ordinary fired solid bricks, and the construction time is shortened by more than 20% ； Approximately 0.24 cubic meters of mortar is required to build 1 cubic meter of ordinary fired solid bricks, while only 0.09 cubic meters of mortar is needed to build 1 cubic meter of ceramsite concrete hollow blocks; the amount of mortar used for the latter is about one-third of that used for the former. Autoclaved aerated concrete hollow blocks suffer less damage and wear compared to ordinary fired solid bricks. Applying plastering under the walls made of ceramsite concrete hollow blocks allows the number of application layers required, which is three for ordinary fired solid brick walls, to be reduced to two by eliminating the intermediate layer; as a result, the material and labor costs associated with the plastering work can be reduced by about 1/3. 　　III. Reducing the workload on workers 　　Based on actual construction calculations, when building a wall with a thickness of 240 millimeters per square meter using ordinary fired solid bricks, workers have to bend over about 180 times to pick up the bricks; whereas when using ceramsite concrete hollow blocks, workers only need to bend over 13 times to pick up the blocks. Although the weight of each ceramsite concrete hollow block is about 4 times that of ordinary fired solid bricks, the number of times one has to bend over is reduced by 14 times. Therefore, the use of ceramsite concrete solid blocks can improve workers’ operating conditions and reduce labor intensity. 　　IV. Increasing the usable area of buildings Calculations show that by replacing 240-mm-thick solid brick walls with 190-mm-thick aerated concrete hollow block walls, not only are properties such as heat and sound insulation improved, but the span between floors can also be increased by 5 cm. This allows a room measuring 3.6 meters by 6 meters to have its usable area increased by about 0.5 square meters, resulting in a 2.5% increase in the building’s effective usable area. 　　 From the above analysis, it can be seen that using ceramsite concrete hollow blocks in place of ordinary fired solid bricks helps to save land, reduce energy consumption, lower pollution, and improve overall efficiency. It also reduces project costs and enhances the functional capabilities of buildings, thereby **increasing the value of those buildings. Therefore, the Linyi area in Shandong Province and the relevant construction authorities provide policy-based support such as preferential treatment to promote the use of new wall materials. Units involved in construction design, construction, supervision, and oversight actively implement the guidelines set out in the documents related to wall material reforms, and they continuously accumulate experience throughout this process, identifying many practical construction tips: ① Stack ceramic aggregate concrete hollow blocks reasonably at the construction site to minimize unnecessary handling and reduce losses. ②The stacking area should be level, and materials should be stacked separately according to different specifications and strength grades. The stacking height should not exceed 1.8 meters; an appropriate distance should be maintained between stacks, and measures should be in place to protect against rain and ensure proper drainage. ③Openings, pipes, trenches, and embedded components specified in the design must be reserved and embedded during masonry; it is strictly prohibited to drill holes in the already constructed walls, as this may damage the overall strength of the walls. ④Under normal circumstances, aerated concrete blocks should be laid upside down, with their bottom sides facing upward, as the wall thickness of the blocks is thinner at the top and thicker at the bottom; laying them upside down facilitates the application of mortar. ⑤When constructing hollow blocks made of ceramsite concrete, the blocks should be aligned vertically with one another and overlapped in a staggered manner to avoid continuous joints. Since the contact area between the blocks in such walls is smaller than that in walls made of hollow bricks, it is required that the mortar filling the horizontal and vertical joints in these walls be at a density of ≥90%. ⑥Due to the significant differences in shrinkage coefficients and moisture content between ceramsite concrete hollow blocks and ordinary sintered solid bricks, they should not be used together when constructing exterior walls. ⑦When constructing ceramic aggregate hollow blocks, mixed mortar is recommended; in addition to meeting the specified strength grade, it should also have good workability and water retention.

1. Used for drainage in landscaping and in hydroponic cultivation: Thanks to its low density and high compressive strength, ceramsite is widely used in drainage layers for urban rooftop gardens and garage roofs to reduce the load on the structures. At the same time, taking advantage of the water and nutrient absorption and release properties of ceramsite, it can be used in soil improvement, landscaping, and hydroponics to retain water, improve air circulation, preserve nutrients, maintain soil looseness over time, prevent soil compaction, and offer good water repellency. 2. Used as raw material for blocks and slabs: Taking advantage of the lightweight and high-strength properties of ceramsite, lightweight ceramsite concrete (blocks, slats) can be formulated, which reduces the weight of structural elements, saves material usage, and lowers the load on foundations. It also possesses properties such as insulation, heat resistance, and sound absorption, thereby improving the functionality of buildings. 3. Used for bridge, ship, equipment foundation, and building foundation underlays; ceramsite can be used to formulate lightweight aggregate concrete, making it an excellent lightweight building material. 4. Used for paving materials and road subgrade treatment: In the treatment of soft soil subgrades, the use of ceramsite can **improve bearing capacity and reduce road surface settlement. The paving material made by mixing it with asphalt and sand and gravel prevents road surfaces from freezing, is wear-resistant, and resistant to cracking. 5. Used for pipeline insulation and toilet bowl backfilling: Ceramsite is employed for insulating industrial equipment pipelines, heating pipes, air conditioning pipes, steam pipes, etc.; it prevents pipes from contracting and becoming brittle at low temperatures, and helps to prevent heat loss at high temperatures. It is used for backfilling in toilet basins and bathtubs, and can **reduce the load on the floor surface, as well as minimize issues such as water absorption and leakage caused by backfill settlement and cracking of the surface layer.