In recent years, self-drilling hollow grouting bolts have been more and more widely used in foundation and foundation engineering, tunnel and underground engineering and slope engineering. For different engineering projects, the self-drilling hollow grouting used The lengths of the anchors are naturally also different. So, what are the length specifications of self-drilling hollow grouting bolts? Today, I will give you a detailed introduction.
Thread Type
There are two thread types for self-drilling hollow grouting bolts, namely R type and T type. These two thread types of rod body have been introduced in detail before, so I won't repeat them here.
Length Specification
According to different engineering needs, there are 4 standard length specifications of self-drilling hollow grouting bolts: 2m, 3m, 4m and 6m. The reason for these length specifications is mainly to consider the restrictions during transportation and use. However, the length specifications of self-drilling hollow grouting bolts are not limited to these, and the common ones are 1m, 1.5m, 2.5m, 3.5m, 5m and so on. If customers have special needs, they can also be made into other lengths. Since the self-drilling hollow grouting bolt has continuous threads throughout the body, it can be cut at any position. That is to say, the self-drilling hollow grouting bolt can be made into various lengths on the construction site to meet different needs. ; At the same time, if the drilling depth of the project is large and a single bolt cannot meet the design requirements, several rod bodies can be connected with a strong connecting sleeve as strong as the rod body to meet the requirements.
Rod Diameter
After talking about the length of the self-drilling hollow grouting bolt, let's talk about its other more important parameter, the diameter of the rod. Now there are many manufacturers of self-drilling hollow grouting bolts on the market, and there are bolts of various diameters, such as 25mm, 30mm, 32mm, 38mm, 40mm, 51mm, 200mm, 300mm. Different diameter bolts have different uses. Small-diameter bolts are often used for building foundations, pile foundations, etc., and large-diameter bolts are often used as self-drilling pipe sheds for advanced support of railways and highways.
Application Field
Because of its unique construction technology of simultaneous drilling, grouting and anchoring, the self-drilling hollow grouting bolt can be used in many projects, especially in the geological conditions of loose and broken holes that are easy to collapse and difficult to form. Self-drilling hollow grouting bolts can be used for slope support, foundation pit support, pile foundation support, tunnel tube shed support and system support, foundation support for transmission towers or wind towers, and repair of old buildings.
Advantages
It combines drilling, grouting, and anchoring together, and is suitable for broken rock and conditions which are difficult to drill holes. Casing pipe is omitted in construction, which can greatly improve construction efficiency.
It has a rich variety of drill bits, and drill bit can be selected according to the properties of rock and soil, which can improve the drilling efficiency.
It can fill cracks, consolidate rock mass and soil layer through pressure grouting, and has good grouting spreading radius and reliable anchoring quality.
The hollow bar can be cut arbitrarily and lengthened by the coupler. Therefore, it is suitable for construction in a narrow space where the large equipment can’t enter.