JPH07100965B2 - Precast concrete stairs construction method and precast concrete stairs - Google Patents

Description

TECHNICAL FIELD The present invention relates to a precast concrete staircase construction method and a precast concrete staircase used in the construction method.

(Prior Art) Conventionally, in the case of constructing stairs, a method of constructing with cast-in-place concrete, a method of using a single precast concrete staircase, and a method of using a steel-framed stair member have been performed.

(Problems to be Solved by the Invention) In a single-piece precast concrete staircase, the number of joints between steps increases, and sealing work increases. In addition, the single precast concrete member is light in weight and requires manual installation, which is uneconomical due to lack of labor.

The present invention has been proposed in view of the above-mentioned problems of the prior art, and the purpose thereof is to reduce the number of joints, reduce the sealing work, and improve the workability of the precast concrete staircase construction method and the construction method. The point is to provide the precast concrete stairs used for the construction method.

(Means for Solving the Problems) In order to achieve the above-mentioned object, according to the precast concrete staircase construction method according to the present invention, after arranging the reinforcing bars around the stairs and after assembling the formwork of the staircase outer surface, In the cutouts provided in a part of the upper part of the floor slab, attach and fix the upper and lower landing semi-precast concrete slabs that expose part of the truss reinforcement arranged in the floor slab at a predetermined position, Next, a precast concrete staircase that integrates the stair climbing formed by integrally forming a joint beam at the center of the back surface of the staircase body formed into a stepped structure having the required riser and tread dimensions Was installed between the landing semi-precast concrete slabs, and then the upper reinforcing bars were laid on the trusses exposed at the upper part of each landing semi-precast concrete slab, and then they were faced to the formwork on the outer surface of the staircase. The inner formwork is assembled and concrete is placed between the two formwork.

Further, the precast concrete stairs according to the present invention, the required kicking portion, in the center of the back surface of the precast concrete staircase body formed into a step shape having tread dimensions, the kicking portion,
The joint beam is formed integrally with the tread, and the reinforcing bars are projected from the side surfaces of the riser and the tread.

(Operation) According to the present invention, a joint beam is integrally formed with the riser and the tread at the center of the back surface of the precast concrete stair body having the required riser and tread dimensions, and the stairs are continuously integrated. Pre-cast concrete stairs that were pre-cast concrete products were pre-molded, the reinforcing bars around the stairs were reinforced, and the formwork on the outside of the staircase was assembled, then in the cutout part provided in a part of the upper part of the floor slab, Attach and fix the upper and lower landing semi-precast concrete slabs that expose part of the truss reinforcement arranged in the floor slab to a fixed position, and erection the precast concrete stairs between the two landing semi-precast concrete slabs. To do.

After that, the upper rebars are laid on the trusses exposed at the upper part of each landing semi-precast concrete slab to assemble the inner formwork facing the formwork on the outer surface of the staircase, and concrete is placed between the two formworks. The precast concrete staircase, the side wall of the staircase, and the upper and lower landing semi-precast concrete plates are integrated to construct a precast concrete staircase.

(Examples) The present invention will be described below with reference to illustrated examples.

Reference numeral 1 denotes a precast concrete staircase, which has a required riser portion 2 and a tread surface 3 at the center of the back surface of a staircase body which is formed in a step shape that is continuous in one step.
And the joint beam 4 is integrally formed with the structure. Further, from the side surfaces of the riser portion 2 and the tread surface 3, an end portion of a reinforcing bar 5 embedded in the precast concrete staircase main body is projected. A suspension anchor 6 is embedded in the tread portion 3.

Thus, after reinforcing the reinforcing bars around the stairs, the frame 7 on the outer surface of the staircase was assembled to prevent deformation, and the trusses arranged in the floor slab were installed in the cutouts provided in the upper part of the floor slab. After mounting and fixing the upper and lower landing semi-precast concrete slabs 8 that expose the streaks 9, the precast concrete stairs 1 are installed between the upper and lower landing semi-precast concrete slabs 8 to prevent sliding, and Is welded and fixed to the truss crests protruding from the concrete plate of the landing semi-precast concrete plate 8. In the figure, w is a welded portion.

Next, the upper reinforcing bar 10 is arranged over the top of the truss bar 9 protruding from the landing semi-precast concrete plate 8,
An inner formwork 7'opposed to the formwork 7 on the outer surface of the staircase is assembled and concrete is poured to construct a stage in which the precast concrete staircase 1 and staircase side wall concrete are integrated. In the figure, 11 is a cast-in-place concrete placed on the above-mentioned semi-precast concrete slab.

(Effects of the Invention) According to the present invention, as described above, a joint beam is formed integrally with the riser and the tread at the center of the back surface of the staircase body formed in a step shape having the required riser and tread dimensions. After making a single precast concrete stair that integrates the stair climbing with the required strength and rigidity, arrange the reinforcing bars around the stairs, assemble the formwork on the outside of the staircase, and then position it The space between the upper and lower landing precast concrete slabs is made by exposing a part of the truss reinforcement arranged in the floor slab to the cutout part provided in the upper part of the floor slab fixed to the above By constructing the precast concrete stairs, the steps of assembling the stairs and the caulking work are omitted, and after arranging the upper rebar of the landing semi-precast concrete plate, the inner formwork facing the formwork on the outer surface of the staircase is Assembling The concrete is cast between the two formwork to integrate the staircase side wall concrete and the precast concrete staircase to construct a staircase, thus saving labor and reducing the number of steps.

Further, the precast concrete stairs have sufficient strength and rigidity due to the joint beam provided in the central portion of the back surface of the staircase body, and can be used as a passage immediately after the installation of the precast concrete stairs is completed.

According to the invention of claim 2, the precast concrete staircase is formed by forming a joint beam integrally with the riser and the tread on the back surface of the precast concrete staircase body formed in the step shape as described above. To ensure that the construction of
By joining the reinforcing bar projecting from the side surface of the riser and the tread to the reinforcing bar of the precast concrete stairs peripheral member, it is possible to prevent the precast concrete staircase installed at a predetermined position from sliding.

[Brief description of drawings]

FIG. 1 is a vertical cross-sectional side view showing an implementation situation of an embodiment of a precast concrete staircase construction method according to the present invention, which is an arrow view of FIG. FIG. 2 is a plan view thereof. FIG. 3 is an enlarged view of part B of FIG. FIG. 4 is a vertical cross-sectional view of a semi-precast concrete slab for landing. FIG. 5 is a view from the arrow of FIG. FIG. 6 is a perspective view showing an embodiment of the precast concrete stairs according to the present invention. FIG. 7 is a partial side view of FIG. FIG. 8 is a view from the arrow of FIG. Explanation of code 1 …… PC stairs 2 …… Raised part 3 …… Treads 4 …… Joint beams 5 …… Reinforcing bar 7, 7 ′ …… Form 8 ： …… Semi-precast concrete version 9 …… Truss bar 10 …… Upper and lower rebars 11 …… In-situ concrete w …… Welded area

Claims (2)

[Claims] 1. A truss arranged in the floor slab in a cutout portion provided in a part of an upper portion of the floor slab after assembling a frame for the outer surface of the staircase by arranging reinforcing bars around the stairs. Attach the upper and lower landing semi-precast concrete slabs that expose a part of the streaks at a predetermined position, fix it, and then, in the center part of the back surface of the staircase body that is molded into a stepped structure with the required riser and tread dimensions,
A precast concrete staircase that integrally integrates a staircase formed by forming a joint beam integrally with the riser and tread is installed between the landing semi-precast concrete plates, and then on top of each landing semi-precast concrete plate. A precast concrete staircase construction characterized by arranging an upper reinforcing bar on the exposed truss bar, then assembling an inner formwork facing the outer surface of the staircase room, and placing concrete between the two formwork. Construction method. 2. A joint beam is integrally formed with the riser and the tread at the center of the back surface of the precast concrete staircase body which is formed into a step shape having the required riser and tread dimensions.
Precast concrete stairs, characterized in that reinforcing bars are projected from the side surfaces of the riser and the tread.