CN103215899A - Reinforcement method for pre-stress continuous beam base plate cracks - Google Patents
Reinforcement method for pre-stress continuous beam base plate cracks Download PDFInfo
- Publication number
- CN103215899A CN103215899A CN2013101658358A CN201310165835A CN103215899A CN 103215899 A CN103215899 A CN 103215899A CN 2013101658358 A CN2013101658358 A CN 2013101658358A CN 201310165835 A CN201310165835 A CN 201310165835A CN 103215899 A CN103215899 A CN 103215899A
- Authority
- CN
- China
- Prior art keywords
- base plate
- stress
- reinforcement
- continuous beam
- symmetrically
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Granted
Links
Images
Landscapes
- Rod-Shaped Construction Members (AREA)
Abstract
The invention relates to a reinforcement method for pre-stress continuous beam base plate cracks. A continuous beam midspan base plate is cracked after a pre-stress pipeline is grouted, so that the maintenance and the reinforcement can not be finished by using a method for re-tensioning pre-stress steel bundles in a beam body. The reinforcement method comprises the following steps of: digging off concrete formed by cracking of the base plate; symmetrically and uniformly applying a pre-stress load to layered stacks from the two sides to the middle within a midspan range; embedding new reinforcement steel bars into drilling holes, resetting steel bar meshes on the top layer and the bottom layer of the conventional base plate, binding and fixing the steel bar meshes, and cleaning floating slurry on the surfaces of the steel bars; and after the concrete achieves the strength, symmetrically and uniformly unloading from two sides to the middle until the load is zero, wherein an elastic upper arch of a beam body pressurizes the base plate, so that a top plate is decompressed; and therefore, pre-stress is applied, and a reinforcement effect is achieved. By using the mechanical characteristics of the stress on a continuous beam, the pre-stress load is applied to a cracked section, and natural pre-stress is supplied to the cracked section; and therefore, the reinforcement construction difficulty and the construction cost are reduced, and consequences caused by the high stress and high creepage are avoided.
Description
Technical field
The invention belongs to the transport development technical field, be specifically related to the reinforcement means that a kind of prestressed continuous beam base plate bursts apart.
Background technology
After continuous beam prestressed strand pipeline pneumatic mortar finished, base plate burst apart, can't be by finishing maintenance and reinforcement in the mode of beam body inner stretch-draw prestressing force steel bundle again.The tradition reinforcement means generally is reinforcement, increases external prestressing steel bundle Scheme of Strengthening as case beam base plate sticking steel plate, base plate.
Base plate sticking steel plate scheme will make institute's sticking steel plate play a role, and must guarantee that steel plate and beam body concrete are stressed jointly, and compatibility of deformation enforcement difficulty is big, and technical difficulty is very big, and the concrete after repairing will bear bigger tensile stress under the operation load action.Base top is set up external prestressing steel bundle scheme, and the baseboard prestress degree is enlarged markedly, and causes the continuous beam distribution of internal force that bigger variation takes place, and underplate concrete is in high-stress state all the time, and the beam body later stage creeps very big; Local tensile stress and local compressive stress before and after anchor block are all bigger, and structure partial structure design and construction difficulty is bigger.
Summary of the invention
The purpose of this invention is to provide the reinforcement means that a kind of prestressed continuous beam base plate bursts apart, overcome existing method and only aspect reinforcement, make an issue of, give the technical problem of a lot of counter productives that existing beam body brings.
The technical solution adopted in the present invention is:
The reinforcement means that a kind of prestressed continuous beam base plate bursts apart is characterized in that:
Realize by following steps:
Step 1: the concrete that cuts the paragraph case beam bottom slab crack that bursts apart;
Step 2: in beam body span centre scope, apply prefabricating load, make case back plate pressurized, the base plate tension by layering preloading symmetrically and evenly in the middle of two side direction; Monitor the downwarp value of respective cross-section in the preloading process in real time, and contrast, guarantee existing structure safety with calculated value;
Step 3: newly-increased reinforcement reinforcing bar is implanted in boring, and former design base top bottom layer of the reinforcing steel net sheet is resetted, and colligation is fixed, and removes the rebar surface laitance;
Step 4: treat to be offloaded to zero symmetrically and evenly by two side direction are middle after concrete reaches design strength; The elasticity arch of beam body makes the base plate supercharging, and the top board decompression is equivalent to apply prestressing force; Survey the arch value in corresponding cross section, and contrast, determine consolidation effect with calculated value.
The present invention has the following advantages:
The reinforcement means that prestressed continuous beam base plate involved in the present invention bursts apart, employing applies the schematic design of prefabricating load, broken through the thinking constraint that traditional Scheme of Strengthening is only being made an issue of by " reinforcement ", utilize the stressed mechanical characteristic of continuous beam that the beam body is applied prefabricating load, for it provides " natural prestressing force ", be skillfully constructed, strengthening construction difficulty and construction cost have been reduced, and heavily stressed, the sequelae that height is crept that can not produce that tradition replenishes that the stretch-draw prestressing force scheme brings, be a kind of comparatively desirable strengthening construction scheme.
Description of drawings
Fig. 1 is a beam body longitudinal cracking beam fragment position schematic diagram;
Fig. 2 beam body applies prefabricating load scheme schematic diagram.
Fig. 3 is that the beam body applies the horizontal preloading schematic diagram of prefabricating load scheme.
The specific embodiment
The present invention will be described in detail below in conjunction with the specific embodiment.
The reinforcement means that a kind of prestressed continuous beam base plate of the present invention bursts apart, realize by following steps:
Step 1: the concrete that cuts the paragraph case beam bottom slab crack that bursts apart;
Step 2: in beam body span centre scope, apply prefabricating load, make case back plate pressurized, the base plate tension by layering preloading symmetrically and evenly in the middle of two side direction; Monitor the downwarp value of respective cross-section in the preloading process in real time, and contrast, guarantee existing structure safety with calculated value; Measured value and theoretical value should be approaching, in range of allowable error;
Step 3: newly-increased reinforcement reinforcing bar is implanted in boring, and former design base top bottom layer of the reinforcing steel net sheet is resetted, and colligation is fixed, and removes the rebar surface laitance;
Step 4:: treat to be offloaded to zero symmetrically and evenly by two side direction are middle after concrete reaches design strength; The elasticity arch of beam body makes the base plate supercharging, and the top board decompression is equivalent to apply prestressing force.Survey the arch value in corresponding cross section, and contrast, determine consolidation effect with calculated value.Measured value and theoretical value should be approaching, in range of allowable error.
In the step 2, described prefabricating load should and can reach that to reinforce purpose be that principle is calculated and determined with safety, the easy construction that can guarantee bridge deck.
Embodiment:
Larger area has taken place and has burst apart in certain Line for Passenger Transportation prestressed concrete continuous beam at the bottom of prestressed stretch-draw, mud jacking finish back mesopore beam.The bridge hole is striden and is arranged employing (30.15+48+56+48+30.15) m continuous box girder, the wide 12.0m of case back, bottom width 6.7m, in stride after a 56m closure section mud jacking finishes, No. 4, No. 5 beam section bottom slab cracks of 56m span, come off, and there are crack, many places, crack width 1mm~2mm, concrete to come off about the wide 50mm of place's seam; The base plate layering of bursting apart, base plate steel mesh reinforcement the most about 14.7cm that sinks; Under the plate top surface topping come to nothing in many places, and reinforced mesh sinks, and observes in case, and base plate is from the layering of bursting apart of longitudinal prestressing bellows.
The analysis-by-synthesis reason of bursting apart, compare through analysis traditional reinforcement scheme pluses and minuses, abnormal deformation does not take place in consideration field observation beam body as a result, do not find that except that base plate there is the cracking situation at other positions yet, illustrate that beam body integral construction quality is good, bottom slab crack is limited to prestressed influence, and the scheme that applies prefabricating load in span centre beam section has been adopted in design.Cut the bottom slab crack concrete, additional plain bars is reorientated and is striden preloading at the beam section place that base plate bursts apart behind the steel bundle and apply prefabricating load, chooses the precompressed scheme of 200-350kN/m, finally requires to select to have applied the 250kN/m prefabricating load according to reinforcement, make case back plate pressurized, the base plate tension.Again build the cracking section concrete, treat to be offloaded to zero symmetrically and evenly by two side direction are middle after concrete reaches design strength, the elasticity arch of beam body makes the base plate supercharging, and the top board decompression is equivalent to apply prestressing force.
Treat to be offloaded to zero symmetrically and evenly by two side direction are middle after concrete reaches design strength; Striding three cross sections arch calculated values that base plate bursts apart in the unloading back is 1.33cm, 1.64cm, 1.84cm, and measured value is respectively 1.36cm, 1.65cm, 1.82cm.
Experienced 900 tons of tests that bridge formation machines fortune beam passes through in the simple supported box beam erection process of objective specially all fronts, the Liang Tiwei generation after reinforcing in this process is any unusual, and consolidation effect is obvious, and this Scheme of Strengthening of presentation of results has reached the design effect of expecting.
It is cited that content of the present invention is not limited to embodiment, and the conversion of any equivalence that those of ordinary skills take technical solution of the present invention by reading manual of the present invention is claim of the present invention and contains.
Claims (1)
1. reinforcement means that the prestressed continuous beam base plate bursts apart is characterized in that:
Realize by following steps:
Step 1: the concrete that cuts the paragraph case beam bottom slab crack that bursts apart;
Step 2: in beam body span centre scope, apply prefabricating load, make case back plate pressurized, the base plate tension by layering preloading symmetrically and evenly in the middle of two side direction; Monitor the downwarp value of respective cross-section in the preloading process in real time, and contrast, guarantee existing structure safety with calculated value;
Step 3: newly-increased reinforcement reinforcing bar is implanted in boring, and former design base top bottom layer of the reinforcing steel net sheet is resetted, and colligation is fixed, and removes the rebar surface laitance;
Step 4: treat to be offloaded to zero symmetrically and evenly by two side direction are middle after concrete reaches design strength; The elasticity arch of beam body makes the base plate supercharging, and the top board decompression is equivalent to apply prestressing force; Survey the arch value in corresponding cross section, and contrast, determine consolidation effect with calculated value.
Priority Applications (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
CN201310165835.8A CN103215899B (en) | 2013-05-08 | 2013-05-08 | A kind of reinforcement means of prestressed continuous beam Bottom slab breaking |
Applications Claiming Priority (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
CN201310165835.8A CN103215899B (en) | 2013-05-08 | 2013-05-08 | A kind of reinforcement means of prestressed continuous beam Bottom slab breaking |
Publications (2)
Publication Number | Publication Date |
---|---|
CN103215899A true CN103215899A (en) | 2013-07-24 |
CN103215899B CN103215899B (en) | 2015-09-16 |
Family
ID=48814024
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
CN201310165835.8A Active CN103215899B (en) | 2013-05-08 | 2013-05-08 | A kind of reinforcement means of prestressed continuous beam Bottom slab breaking |
Country Status (1)
Country | Link |
---|---|
CN (1) | CN103215899B (en) |
Cited By (5)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
CN105625199A (en) * | 2016-03-18 | 2016-06-01 | 浙江大学城市学院 | Processing method and repairing structure for variable cross-section continuous box beam bottom plate cracking area |
CN105714698A (en) * | 2016-04-11 | 2016-06-29 | 沈阳建筑大学 | Cracking reinforcing structure for main girder bottom plate of wide-width box beam bridge and construction method of cracking reinforcing structure |
CN105735152A (en) * | 2016-04-11 | 2016-07-06 | 沈阳建筑大学 | Girder baseplate crack reinforced structure for variable-section box girder bridge and construction method thereof |
CN105970838A (en) * | 2016-06-03 | 2016-09-28 | 湖南城市学院 | Deck type arch bridge vault padding unloading and reinforcing construction method and application |
CN114398775A (en) * | 2022-01-04 | 2022-04-26 | 交通运输部公路科学研究所 | Concrete beam service life prediction method considering cracking damage step stiffness |
Citations (7)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
DE4313227A1 (en) * | 1993-04-22 | 1994-10-27 | Horst Dr Ing Kinkel | Prestressed reinforcement element |
CN1587531A (en) * | 2004-06-30 | 2005-03-02 | 清华大学 | Method for anti-cracking in hogging moment area of steel-concrete combined beam |
KR100733609B1 (en) * | 2006-03-31 | 2007-06-28 | 주식회사 제일엔지니어링 | Reinforcing method of concrete structures using camber of steel beam |
CN101397854A (en) * | 2008-01-23 | 2009-04-01 | 贵州大学 | Enveloping prestressing force fastening type steel tube concrete column and reinforcement method |
CN101942903A (en) * | 2010-08-16 | 2011-01-12 | 合肥工业大学 | Device for reinforcing concrete beam slab by pretension carbon fiber plate and construction method |
JP2011174541A (en) * | 2010-02-24 | 2011-09-08 | Toshiba Corp | Method for preventing development of cracks of piping |
CN102561214A (en) * | 2012-02-15 | 2012-07-11 | 中南大学 | Steel plate and concrete composite structure reinforcing method for positive bending moment area |
-
2013
- 2013-05-08 CN CN201310165835.8A patent/CN103215899B/en active Active
Patent Citations (7)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
DE4313227A1 (en) * | 1993-04-22 | 1994-10-27 | Horst Dr Ing Kinkel | Prestressed reinforcement element |
CN1587531A (en) * | 2004-06-30 | 2005-03-02 | 清华大学 | Method for anti-cracking in hogging moment area of steel-concrete combined beam |
KR100733609B1 (en) * | 2006-03-31 | 2007-06-28 | 주식회사 제일엔지니어링 | Reinforcing method of concrete structures using camber of steel beam |
CN101397854A (en) * | 2008-01-23 | 2009-04-01 | 贵州大学 | Enveloping prestressing force fastening type steel tube concrete column and reinforcement method |
JP2011174541A (en) * | 2010-02-24 | 2011-09-08 | Toshiba Corp | Method for preventing development of cracks of piping |
CN101942903A (en) * | 2010-08-16 | 2011-01-12 | 合肥工业大学 | Device for reinforcing concrete beam slab by pretension carbon fiber plate and construction method |
CN102561214A (en) * | 2012-02-15 | 2012-07-11 | 中南大学 | Steel plate and concrete composite structure reinforcing method for positive bending moment area |
Non-Patent Citations (2)
Title |
---|
李延和等: "高效预应力加固技术发展综述", 《建筑结构》 * |
黄玉萍: "变截面预应力连续箱梁桥底板崩裂加固措施及施工工艺", 《福建建材》 * |
Cited By (9)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
CN105625199A (en) * | 2016-03-18 | 2016-06-01 | 浙江大学城市学院 | Processing method and repairing structure for variable cross-section continuous box beam bottom plate cracking area |
CN105714698A (en) * | 2016-04-11 | 2016-06-29 | 沈阳建筑大学 | Cracking reinforcing structure for main girder bottom plate of wide-width box beam bridge and construction method of cracking reinforcing structure |
CN105735152A (en) * | 2016-04-11 | 2016-07-06 | 沈阳建筑大学 | Girder baseplate crack reinforced structure for variable-section box girder bridge and construction method thereof |
CN105714698B (en) * | 2016-04-11 | 2017-03-08 | 沈阳建筑大学 | A kind of wide box girder bridge girder Bottom slab breaking ruggedized construction and its construction method |
CN105735152B (en) * | 2016-04-11 | 2017-04-19 | 沈阳建筑大学 | Girder baseplate crack reinforced structure for variable-section box girder bridge and construction method thereof |
CN105970838A (en) * | 2016-06-03 | 2016-09-28 | 湖南城市学院 | Deck type arch bridge vault padding unloading and reinforcing construction method and application |
CN105970838B (en) * | 2016-06-03 | 2018-06-01 | 湖南城市学院 | Deck Arch Bridges vault filler unloads and reinforced construction method and application |
CN114398775A (en) * | 2022-01-04 | 2022-04-26 | 交通运输部公路科学研究所 | Concrete beam service life prediction method considering cracking damage step stiffness |
CN114398775B (en) * | 2022-01-04 | 2022-08-16 | 交通运输部公路科学研究所 | Concrete beam service life prediction method considering cracking damage step stiffness |
Also Published As
Publication number | Publication date |
---|---|
CN103215899B (en) | 2015-09-16 |
Similar Documents
Publication | Publication Date | Title |
---|---|---|
El-Hacha et al. | Behaviour of hybrid FRP–UHPC beams subjected to static flexural loading | |
Inácio et al. | Strengthening of flat slabs with transverse reinforcement by introduction of steel bolts using different anchorage approaches | |
CN103215899A (en) | Reinforcement method for pre-stress continuous beam base plate cracks | |
Ban et al. | Available rotation capacity of composite beams with high-strength materials under sagging moment | |
Fam et al. | Built-up hybrid composite box girders fabricated and tested in flexure | |
CN102966050A (en) | Longitudinal connection method for steel-concrete combined beam and existing reinforced concrete T beam | |
CN103195259A (en) | Foam concrete prefabricated slab and method for reinforcing concrete structure by same | |
Hasan et al. | The strength of hollow concrete block walls, reinforced hollow concrete block beams, and columns | |
Ahmed et al. | Steel fiber as replacement of minimum shear reinforcement for one-way thick bridge slab | |
CN105544415A (en) | Concrete bridge reinforcing method and structure | |
Pournasiri et al. | Behavior of ultrahigh-performance concrete bridge decks with new Y-shape FRP stay-in-place formworks | |
Pirayeh Gar et al. | Comparative experimental performance of bridge deck slabs with AFRP and steel precast panels | |
CN109537806A (en) | A kind of " T-type " partial precast combination beam | |
Abo-Alanwar et al. | A Smart Reinforced Steel Wire Mesh U-Shape Jacketing Technique in Strengthening and Retrofitting RC Beams | |
Morcous et al. | Implementation of Precast Concrete Deck System NUDECK (2nd Generation) | |
CN203939023U (en) | Anti-seismic prefabricated concrete triangle solid pile | |
Brunton et al. | Punching shear failure in double-layer pultruded FRP grid reinforced concrete bridge decks | |
Lam | Composite steel beams with precast hollow core slabs: behaviour and design | |
Deng et al. | Strain driven mode-switching analytical framework for estimating flexural strength of RC box girders strengthened by prestressed CFRP plates with experimental validation | |
Chen et al. | Flexural behaviour of hybrid FRP-UHPC girders under static loading | |
CN212241557U (en) | Prestressed double-core drawing rod | |
CN218989887U (en) | I-beam structure of assembled perforated waffle bridge deck | |
CN109024271B (en) | Construction method of built-in concrete beam bridge steel-concrete anchor capable of limiting local cracking | |
Du et al. | Response of concrete beams partially prestressed with external unbonded carbon fiber-reinforced polymer tendons | |
CN205205698U (en) | Concrete bridge reinforced structure |
Legal Events
Date | Code | Title | Description |
---|---|---|---|
C06 | Publication | ||
PB01 | Publication | ||
C10 | Entry into substantive examination | ||
SE01 | Entry into force of request for substantive examination | ||
C14 | Grant of patent or utility model | ||
GR01 | Patent grant |