Steel mesh reinforcement pea gravel concreten reinforces the method for prefabricated concrete hollow slab
Technical field
The present invention relates to building engineering field, be specifically related to structure reinforcement and repair, is a kind of method utilizing steel mesh reinforcement pea gravel concreten to reinforce prefabricated concrete hollow slab.
Background technology
Precast hollow slab (i.e. prefabricated concrete hollow slab) obtains large scale application in China, and the brick masonry structure building of enormous amount and peasant's self-built housing adopt precast hollow slab flooring.Along with structure is aging and service load increases, need reinforce precast hollow slab flooring.
Steel mesh reinforcement pea gravel concreten reinforcing technique obtains application in concrete structure reinforcement, but be not also applied to precast hollow slab flooring to reinforce, this aspect method has the efficient feature of low skill, and application prospect can the phase, without the need to replacing old precast hollow slab, man power and material's cost can be reduced.
Summary of the invention
The present invention aims to provide the method that steel mesh reinforcement pea gravel concreten reinforces prefabricated concrete hollow slab.
This steel mesh reinforcement pea gravel concreten reinforces prefabricated concrete hollow slab (i.e. precast hollow slab, hereinafter referred to as precast hollow slab) method, its technical scheme is, according to the force modes of freely-supported precast hollow slab, (top is pressurized edge, bottom is tension edge), by knock out hole top in the middle of prefabricated concrete hollow slab concrete and in relevant position assembling reinforcement mesh sheet with build pea gravel concreten and improve its supporting capacity.
Steel mesh reinforcement pea gravel concreten reinforces the method for prefabricated concrete hollow slab, comprises the following steps:
(1) knock out the concrete on hole top in the middle of prefabricated concrete hollow slab, and hole is removed clean;
(2) to arrange in corresponding position in hole that tension indulges muscle, tension rib, pressurized indulge muscle and horizontal distribution muscle:
The order of reinforcing steel bar laying is followed successively by that tension indulges muscle (in hole), horizontal distribution muscle (above hole), pressurized indulge muscle (above hole) and tension rib (be connected tension and indulge muscle and horizontal distribution muscle), in its Hole tension indulge the placement location of muscle should near the bottom of prefabricated concrete hollow slab, and respectively in middle hole arrange one;
The spacing of horizontal distribution muscle is 180 ~ 210mm, is preferably 200mm; The spacing that pressurized indulges muscle is 95 ~ 110mm, and be preferably 100mm, tension rib spacing on the direction of horizontal distribution muscle is 350 ~ 450mm, is preferably 400mm; All reinforcing bars should select grade III steel;
(3) support template concreting:
After shutoff is carried out in hole end in the middle of prefabricated concrete hollow slab, concreting, fills up middle hole, and newly placed concrete layer thickness should higher than former component surface 40 ~ 50mm;
Before concreting, shutoff is carried out, in case concrete occurs excessive when building in hole end in the middle of prefabricated concrete hollow slab; Hole end plugging material can select the common material such as fragment of brick and mortar.In addition, during concreting except middle hole need being filled up, still should all building higher than in former member upper surface 40mm ~ 50mm height.Concrete is the solidifying soil of microlith.
Steel mesh reinforcement pea gravel concreten of the present invention reinforces the method for prefabricated concrete hollow slab, not only reliability is higher, and the supporting capacity of prefabricated concrete hollow slab (i.e. precast hollow slab) flooring can be significantly improved, the follow-up instructions for use of prefabricated concrete hollow slab can be ensured; Show according to the test that above-mentioned reinforcement means carries out, after reinforcing, the unguyed plate of precast hollow slab bearing capacity ratio increases by more than 100%.
Accompanying drawing explanation
Fig. 1 is the longitudinal sectional drawing (sectional drawing on hole direction) that steel mesh reinforcement pea gravel concreten reinforces prefabricated concrete hollow slab.
Fig. 2 is that steel mesh reinforcement pea gravel concreten reinforces the sectional view of prefabricated concrete hollow slab in A-A direction.
Fig. 3 is the schematic diagram of embodiment 2
1-prefabricated concrete hollow slab in figure, the former prestressing force tension of 2-indulges muscle, 3-newly placed concrete layer, 4-increases tension newly and indulges muscle, 5-pressurized indulges muscle, 6-horizontal distribution muscle, 7-tension rib, 8-hole end plugging material, the middle hole of 91a, 92a, 93a, 94a, 91b, 92b, 93b, 94b, 95b-precast hollow slab.
Detailed description of the invention
Embodiment 1
(1) as depicted in figs. 1 and 2, in prefabricated concrete hollow slab (precast hollow slab) 1, there are 4 holes (91a, 92a, 93a and 94a), and below hole, have former prestressing force tension to indulge muscle 2; First the load that prefabricated concrete hollow slab 1 bears is unloaded; Then knock out the concrete at the middle two circular cavities 92a of floor prefabricated concrete hollow slab and 93a top (i.e. pressurized edge), and hole is removed clean;
The hole number of this prefabricated concrete hollow slab is 4, therefore knocks out middle two respectively, and namely the concrete in second hole (i.e. hole 92a and 93a) is played on left side and right side, and is removed by hole clean;
(2) bottom in hole 92a and 93a, each laying newly-increased tension indulges muscle 4, then above hole, successively arrangement pitch is respectively the horizontal distribution muscle 6 of 200mm and 100mm and pressurized indulges muscle 5, finally in middle hole, arrange tension rib 7, muscle and horizontal distribution muscle is indulged for connecting newly-increased tension, on the direction of horizontal distribution muscle, the spacing of tension rib is 400mm; Newly-increased tension is vertical to be parallel to former prestressing force tension and to indulge muscle, and it is vertical that newly-increased horizontal distribution muscle and newly-increased tension indulge muscle, and it is vertical with the horizontal distribution muscle increased newly that the pressurized increased newly indulges muscle;
(3) after propping up good template, as shown in Figure 1, by hole 92a and 93a end plugging material 8(in the middle of prefabricated concrete hollow slab as the common material such as fragment of brick and mortar) carry out shutoff; During following concreting except middle hole need being filled up, still should all building higher than in former member upper surface 40mm ~ 50mm height, form the newly placed concrete layer 3 that thickness is 40 ~ 50mm, natural curing is after 28 days, and the precast hollow slab adopting this method steel mesh reinforcement pea gravel concreten to reinforce can continue carrying.
Embodiment 2
(1) as shown in figures 1 and 3, in prefabricated concrete hollow slab 1, there are 5 holes (91b, 92b, 93b, 94b and 95b), and below hole, have former prestressing force tension to indulge muscle 2; First the load that prefabricated concrete hollow slab 1 bears is unloaded; Then knock out the concrete at the middle two circular cavities 92b of floor prefabricated concrete hollow slab and 94b top (i.e. pressurized edge), and hole is removed clean;
The hole number of this precast hollow slab is 5, therefore knocks out middle two respectively, and namely the concrete in second hole (i.e. hole 92b and 94b) is played on left side and right side, and is removed by hole clean;
(2) bottom in hole 92b and 94b, each laying newly-increased tension indulges muscle 4, then above hole, successively arrangement pitch is respectively the horizontal distribution muscle 6 of 200mm and 100mm and pressurized indulges muscle 5, finally in middle hole, arrange tension rib 7, muscle and horizontal distribution muscle is indulged for connecting newly-increased tension, on the direction of horizontal distribution muscle, the spacing of tension rib is 400mm; Newly-increased tension is vertical to be parallel to former prestressing force tension and to indulge muscle, and it is vertical that newly-increased horizontal distribution muscle and newly-increased tension indulge muscle, and it is vertical with the horizontal distribution muscle increased newly that the pressurized increased newly indulges muscle; (3) after propping up good template, as shown in Figure 1, by hole 92b and 94b end plugging material 8(in the middle of precast hollow slab as the common material such as fragment of brick and mortar) carry out shutoff; During following concreting except middle hole need being filled up, still should all building higher than in former member upper surface 40mm ~ 50mm height, form the newly placed concrete layer 3 that thickness is 40 ~ 50mm, natural curing is after 28 days, and the precast hollow slab adopting this method steel mesh reinforcement pea gravel concreten to reinforce can continue carrying.
According to above detailed description of the invention, devise the test specimen the anti-bending bearing capacity experimental study carrying out three branch loadings of reinforcing front and back precast hollow slab.Result of the test shows, after adopting steel mesh reinforcement pea gravel concreten to reinforce, the unguyed contrast groups precast hollow slab of ultimate bearing force rate of precast hollow slab increases above more than 100%.