• 黔西南Fully grouted sleeve

A fully grouted sleeve refers to a sleeve with both ends inserted with steel bars and grouted to form a complete connection, mainly used for connecting horizontal steel bars.

Insert the fully grouted sleeve rubber plug into the left end (pre installed end) of the sleeve, insert the steel bars from the rubber plug hole, and determine the penetration depth according to the connection requirements of different types of steel bars. After being inserted to the design depth, it is tied together with other steel bars and placed into the component mold. Align the right end of the sleeve (on-site installation end) with the matching fixture installed on the template and flatten the edge of the template. Install corrugated pipes at the grouting and exhaust ports, and use magnetic suction cup positioning fixtures to position the corrugated pipes before pouring concrete into shape. When installing the components, align the open end of the grouting sleeve with the steel bars extending from the lower wall panel, seal or seat the grout, and inject the matching grouting material from the grouting port. When the exhaust hole overflows, seal the exhaust hole and grouting hole. After the grouting material reaches a certain strength, the longitudinal steel bars are connected into a whole.

The function and installation position of grouting sleeve

The obvious difference between prefabricated concrete structures and cast-in-place concrete structures in terms of form is the discontinuity of concrete at the joints and the cutting of steel bars caused by component segmentation and prefabrication. The reliability of steel bar connections has become a key technical issue in order to achieve an assembled integral concrete structure that is equivalent to cast-in-place. Sleeve grouting connection is the most commonly used technical means.

Sleeve grouting connection is the process of connecting steel bars that have been disconnected from prefabricated components through a specially designed steel sleeve. The space between the steel bars and the inner cavity of the sleeve is filled with non shrink, high-strength grouting material to form a steel bar sleeve grouting connection. Sleeve, as a steel connector, plays a particularly important role in prefabricated buildings. After the sleeve is installed in place, the grouting hole and discharge hole of the sleeve should be located above the sleeve. A single sleeve grouting special tool or equipment should be used for pressure grouting. The grouting material is injected into the grouting hole from one end of the sleeve, and after flowing out from the other end, the grouting surface of the grouting material in the joint of the inlet and outlet holes should be higher than the highest point on the outer surface of the sleeve.

The following two pictures can vividly demonstrate the position and installation method of grouting sleeves in prefabricated components of prefabricated buildings.

Construction process of sleeve grouting

The entire process of grouting can be divided into the following steps in detail: vertical component hoisting in place → base treatment → grouting chamber sealing → grouting construction preparation → preparation of joint slurry → inspection of joint slurry → injection of grout → overflow of grout → stopping grouting → plugging of rubber plug grouting slurry → removal of grouting discharge pipe blockage on the component → final inspection → sleeve connection test. Among them, the grouting process is the most important and difficult to understand in the entire process. Because the grouting sleeve is inside the prefabricated component, we cannot see the entire grouting process. In order to demonstrate the entire grouting process in detail, we will use the following animation to illustrate it in detail.

The fully grouted sleeve connection technology is suitable for fields such as reinforced concrete structure engineering, steel structure engineering, bridge engineering, offshore oil extraction platform engineering, and offshore wind power towers. Grouting sleeve connection technology is a new type of steel structure connection method that has emerged due to the needs of engineering practice and technological development. The emergence of this connection method has made up for the shortcomings of traditional steel structure connection methods (mainly including welding and bolt connections) and has been rapidly developed and applied.