Permeable concrete is composed of cement and asphalt as cementing materials mixed with high-quality aggregates of the same size or discontinuous grade, and is a mixed material with a certain void ratio. When it is made into concrete pavement, slope protection and its products, it can obtain drainage, anti-slip, sound absorption, noise reduction and water seepage effects, which can improve the surface ecological cycle, facilitate traffic safety, protect the living environment, and solve the problem of large-scale modern city construction. The negative impact.
So far, there are three main types of permeable concrete for road paving and flooring.
1. Cement permeable concrete
This is a sand-free, porous concrete prepared by using silicate cement as a cementing material, using a single-stage coarse aggregate, and using little or no fine aggregate. This type of concrete generally uses higher strength cement with a ashing ratio of 3.0 to 4.0 and a water to cement ratio of 0.3 to 0.35.
The concrete mix is relatively dry and hardened by pressure vibration to form concrete with interconnected pores. The hardened concrete usually contains about 20% of connected pores, and the corresponding performance density is lower than that of ordinary concrete, usually 1 700~2 200 kg/m3. The compressive strength can reach 15~35 MPa, the flexural strength can reach 3~5 MPa, and the water permeability coefficient is 1~15mm/s. Concrete manufacturer
The permeable concrete is low in cost and simple to manufacture and can be used for road paving and pre-finished applications. However, due to the inclusion of more connected pores, its strength, wear resistance and frost resistance are the main indicators of engineering application technology.
2, polymer permeability concrete
This is a water-permeable concrete formulated with a single-grain grade coarse aggregate and asphalt or polymer resin as a cementitious material. Compared with cement-permeable concrete, this kind of concrete has higher strength but higher cost. At the same time, due to the poor weather resistance of organic cementitious materials, it is easy to age under the action of sunlight and atmospheric factors, and its performance is greatly affected by temperature. Especially when the temperature rises, it tends to soften the flow and affect the water permeability. Therefore, anti-aging and thermal stability are the key to quality assurance under the premise of ensuring voids. Suzhou concrete
3. Sintered water-permeable products
The granules and slurry of minerals such as discarded tiles, feldspar, kaolin, clay, etc. are mixed, pressed into a body, and calcined at a high temperature, and have a porous structure. The water permeable material has high strength, good wear resistance and excellent durability, but the sintering process requires energy consumption and high cost, and is suitable for gardening, plaza and landscape road paving parts with small dosage.