Building basement supporting
Technical field
The present invention relates to a kind of basement supporting, more particularly to building basement supporting.
Background technology
Traditional basement support technology is basement supporting there is provided concrete maintains basement supporting stable to supportting, but
It is that concrete can greatly increase basement support cost to support, very big influence also is caused to earthwork outward transport in addition, so as to be delayed
Construction period.If by the safe and orderly adjustment of stress in basement Bracing Process, transfer and reallocated, make basement
Supporting obviously can obtain significant economic benefit and duration benefit in the case of without inner support.But how in basement branch
No concrete is avoided in shield work progress to problem that safety problem in the case of support is that engineering staff faces.
The content of the invention
The present invention is to provide a kind of building basement supporting, solves problem of the prior art.
Therefore, the present invention takes certain technical measures plays the inner supporting structure body that temporary support is acted on progressively to replace
System, so as to ensure after provisional bracing demolition, engineering construction can continue safely and conveniently to carry out.The present invention is applied to excavate deeply
Spend for the basement of 3.5~5m depth.
First operating mode basement supporting construction is using as follows:
Support pile uses cast-in-situ bored pile, a diameter of 600~900mm of cast-in-situ bored pile.From support pile central point outside
Water-stop curtain is set to 1.5~2m, and water-stop curtain uses three axle cement mixing piles, and three axle cement mixing pile stake footpaths are 600mm
Or 500mm, adjacent three axles cement mixing pile is mutually twisted, and occlusion distance is 200mm or 150mm.Direction on the inside of support pile
Top sets first of steel waist rail, first of steel waist rail top mark high, first steel waist rail and supporting identical with support pile top mark height
The embedded bar of stake is welded to connect, and prestressed cable anchorage is in first of steel waist rail, and 1.5~2.5m of digging depth positions are in engineering
The engineering pile that stake is placed above below billet, billet has 2~4.Billet thickness is 10~12cm, and billet is set
Position is fluted in the middle of billet from 13~15m of basement edge, and recessed poor depth is 8~12mm, and length and width is 10~
15cm, the reinforcing sector width of basement passive area is 1m scopes within the tangent line of support pile outward flange, and stabilization zone depth is basement
1.5m~2m below substrate.First time bracing members are set between first of steel waist rail and billet.
Second operating mode basement supporting construction is using as follows:
Second steel waist rail is set on the inside of support pile in the middle part of direction, and second steel waist bottom elevation is first time earth excavation
The embedded bar of depth, second steel waist rail and support pile is welded to connect, and second prestressed cable anchorage is in second steel waist
Beam, engineering pile is cut in second of earth excavation, engineering pile top mark height, engineering identical with basement bottom board substrate absolute altitude
Stake sets billet above, and second of bracing members, billet and second steel waist are set between billet and first of steel waist rail
Second of bracing members is set between beam.
Construction procedure includes:
(1), construction work stake.Set construction elevation and second waist rail elevation of top at the top of the engineering pile of billet neat
Flat, Other Engineering stake top portion construction elevation is 10cm below the absolute altitude of basement bottom board bottom.
(2), construction supporting stake.
(3), construction water-stop curtain.
(4) basement passive area, is reinforced.
Basement passive area, which is reinforced, uses churning concrete stake.
(5), first of steel waist rail of construction and prestress anchorage cable.
The embedded bar of first of steel waist rail and support pile is welded.
Steel waist rail presses continuous beam calculating.During the moment of flexure design value of waist rail, anchor cable pulling force takes the base calculated during structural analysis
This combined effect is used as fulcrum axial-load effect value.
Steel waist rail is from single channel-section steel or double flute steel or double I-steel, when from double flute steel or double I-steel, steel wale
Entirety should be welded as, is welded to connect and uses fillet weld, weld bead height is no less than 8mm.
The construction of first steel waist rail is constructed prestress anchorage cable after finishing.
Prestress anchorage cable technical parameter is using as follows:When anchor rope grouting uses cement mortar, the ratio of mud preferably takes 0.45~
0.50;During using cement mortar, the ratio of mud preferably takes 0.40~0.45, and cement-sand ratio preferably takes 0.5~1.0, and mix is preferably selected with sand
Medium-fine sand, clay content must not exceed the 3% of sand weight.3%.During using secondary pressure grouting process, secondary pressure slip casting is preferably adopted
With the cement mortar of the ratio of mud 0.50~0.55, secondary grouting pipe answers lashing on the body of rod, and the end grout outlet of Grouting Pipe should
Taking prevents that slurries are into the seal approach of Grouting Pipe before slip casting, and during secondary pressure slip casting, grouting pressure is not preferably less than 1.5MPa;
When being segmented secondary grouting technique using anchoring section, slip casting is carried out preferably after the intensity of hole body grouting soil reaches 5MPa, splitting
The slurry outlet of Grouting Pipe should be set along anchor rod anchored section of total length, grouting sequence should since anchor pole end, be segmented from inside to outside according to
It is secondary to carry out.
Anchor cable construction is using as follows:
1) after the intensity of injecting cement paste reaches the 75% of design strength and not less than 15MPa, the tensioning of anchor cable can be carried out
Locking.
2) using the method for the overall tensioning fixation of steel strand wires.
3) anchorage cable stretching should be loaded gently, and loading classification is not preferably greater than 0.3, and the interval time of every grade of load is not less than
3min;Before anchor cable locking, stable a period of time should be kept under maximum stretching force, to sandy soil stratum, stabilization time should be greater than
5min~10min, to cohesive soil stratum, stabilization time should be greater than 15min.
4) anchor cable rope timing, (1.1~1.15) times of the desirable design tensioning lock definite value of tensioning value.
5) in the 48h after anchor cable locking, when anchor cable pulling force is less than design lock value 90%, it should be locked again;
Anchor cable locking is still considered as loss of prestress caused by adjacent anchorage cable stretching locking, when anchor cable pulling force is less than design lock value
When 90%, it should be locked again.
6) anchor cable outer end preferably uses cold cut segmentation method to cut off after locking;Steel strand wires after being cut outside anchorage retain length not
50mm is should be less than, during using thermal cutting, no less than 80mm.
(6), at the top of local excavation's basement periphery soil to second steel waist rail.
(7), first time bracing members are set.
Billet is placed above after being flattened at the top of engineering pile, first time bracing members withstand on billet groove by bracing members branch
Interior blending bolt is fixed.
Because bracing members spacing is most important to basement excavation safety.Using simulation analysis of computer, according to basement
Maximum soil deep soil movement is as datum mark at the 0.5m of outside, and maximum soil deep soil movement control is 2mm.First time bracing members set deep
Spend for 1.5~2.5m of digging depth positions.Table 1 is first time bracing members spacing and depth relationship, according to simulation analysis of computer
As a result, first time bracing members set spacing to be 1.35~3.75m.
Table 1 first time bracing members spacing and depth relationship
(8) soil in the middle of basement, is excavated.
(9), local excavation to basement periphery is native to basement substrate.
(10), second of bracing members are set
Second of bracing members sets two roads.The bracing members of second steel waist rail, the bracing members of first of steel waist rail are first set
It is configured again in the case of first first time bracing members of dismantling, method to set up is to set second at once after removing first time bracing members
Secondary bracing members.
Second of bracing members sets depth to be 2~3m of digging depth positions.Table 2 is that second of bracing members spacing is closed with depth
System, according to simulation analysis of computer result, second of bracing members sets spacing to be 1.70~3.83m.
Second of the bracing members spacing of table 2 and depth relationship
(11) soil in the middle of basement, is excavated.
(12), pour and smash basement bottom board and concrete side walls.Concrete side walls set pre-buried with bracing members junction position
Hole.Embedded water stop rubber strip blocks infiltration path in the middle part of the basement bottom board of billet position.
(13), support replacement is set.
Dead slot clogs macadam-aggregate mix between concrete side walls and support pile.Macadam-aggregate mix be packed in concrete side walls with
Purpose is to make to be converted to the load of bracing members into the evenly load for acting on support pile in dead slot between support pile, for lower step
Bracing members are removed to be ready.
Reasonable macadam-aggregate mix level, which is matched somebody with somebody, can both avoid lacking aerial construction formed by sand packing process between particle after compacting,
Ensure that between emery dust particulate has enough bulky grains to form skeleton, meets intensity requirement.
Macadam-aggregate mix use rubble, sand grains, powder compound, ballast grain sizes be 15~2mm, quality volume be 30%~
40%;Sand grains particle diameter is 2~0.1mm, and quality volume is 40%~50%;Powder particle diameter is less than 0.1mm, and quality volume is 20%
~30%.
(14) bracing members and billet, are removed.
(15) basement roof concrete, is poured.
(16), close that bracing members are pre-buried and billet position underplate concrete with water-proof concrete.
Construction cost of the present invention is low, and the construction period is short.
Brief description of the drawings
Fig. 1 is the first operating mode basement supporting schematic diagram, and Fig. 2 is the second operating mode basement supporting schematic diagram.
In each accompanying drawing:1st, support pile, 2, first of steel waist rail, 3, prestress anchorage cable, 4, water-stop curtain, 5, basement it is passive
Area, 6, first of bracing members, 7, billet, 8, engineering pile, 9, second steel waist rail, 10, second of bracing members.
Embodiment
Embodiment one
First operating mode basement supporting construction is using as follows:
Support pile 1 uses cast-in-situ bored pile, a diameter of 600~900mm of cast-in-situ bored pile.From on the outside of the central point of support pile 1
Water-stop curtain 4 is set at 1.5~2m of direction, and water-stop curtain 4 uses three axle cement mixing piles, and three axle cement mixing pile stake footpaths are
600mm or 500mm, adjacent three axles cement mixing pile is mutually twisted, and occlusion distance is 200mm or 150mm.In support pile 1
Side sets first of steel waist rail 2, high, the first steel waist identical with the top mark height of support pile 1 of first of top mark of steel waist rail 2 to top
The embedded bar of beam 2 and support pile 1 is welded to connect, and prestress anchorage cable 3 is anchored at first of steel waist rail 2, and digging depth 1.5~
2.5m positions have 2~4 in the engineering pile 8 that engineering pile 8 is placed above below billet 7, billet 7.The thickness of billet 7 is
10~12cm, the set location of billet 7 is fluted in the middle of billet 7 from 13~15m of basement edge, and recessed poor depth is 8~
12mm, length and width is 10~15cm, and the reinforcing sector width of basement passive area 5 is 1m within the outward flange tangent line of support pile 1
Scope, stabilization zone depth is 1.5m~2m below basement substrate.Set for the first time between first of steel waist rail 2 and billet 7
Bracing members 6.
Second operating mode basement supporting construction is using as follows:
Second steel waist rail 9 is set in the middle part of the inner side direction of support pile 1, and the bottom absolute altitude of second steel waist rail 9 is the first time earthwork
Cutting depth, the embedded bar of second steel waist rail 9 and support pile 1 is welded to connect, and second prestress anchorage cable 3 is anchored at second
Road steel waist rail 9, engineering pile 8 is cut in second of earth excavation, the top mark of engineering pile 8 height and basement bottom board substrate absolute altitude
Identical, engineering pile 8 sets billet 7 above, and second of bracing members 10, steel pad are set between billet 7 and first of steel waist rail 2
Second of bracing members 10 is set between plate 7 and second steel waist rail 9.
Construction procedure includes:
(1), construction work stake 8.The top construction elevation of engineering pile 8 of billet 7 is set with being marked at the top of second waist rail
Height is flushed, and Other Engineering 8 top construction elevations of stake are 10cm below the absolute altitude of basement bottom board bottom.
(2), construction supporting stake 1.
(3), construction water-stop curtain 4.
(4) basement passive area 5, is reinforced.
Basement passive area 5, which is reinforced, uses churning concrete stake.
(5), first of steel waist rail 2 of construction and prestress anchorage cable 3.
The embedded bar of first of steel waist rail 2 and support pile 1 is welded.
Steel waist rail presses continuous beam calculating.During the moment of flexure design value of waist rail, anchor cable pulling force takes the base calculated during structural analysis
This combined effect is used as fulcrum axial-load effect value.
Steel waist rail is from single channel-section steel or double flute steel or double I-steel, when from double flute steel or double I-steel, steel wale
Entirety should be welded as, is welded to connect and uses fillet weld, weld bead height is no less than 8mm.
Construction prestress anchorage cable 3 after first of construction of steel waist rail 2 is finished.
The technical parameter of prestress anchorage cable 3 is using as follows:When anchor rope grouting uses cement mortar, the ratio of mud preferably takes 0.45~
0.50;During using cement mortar, the ratio of mud preferably takes 0.40~0.45, and cement-sand ratio preferably takes 0.5~1.0, and mix is preferably selected with sand
Medium-fine sand, clay content must not exceed the 3% of sand weight.3%.During using secondary pressure grouting process, secondary pressure slip casting is preferably adopted
With the cement mortar of the ratio of mud 0.50~0.55, secondary grouting pipe answers lashing on the body of rod, and the end grout outlet of Grouting Pipe should
Taking prevents that slurries are into the seal approach of Grouting Pipe before slip casting, and during secondary pressure slip casting, grouting pressure is not preferably less than 1.5MPa;
When being segmented secondary grouting technique using anchoring section, slip casting is carried out preferably after the intensity of hole body grouting soil reaches 5MPa, splitting
The slurry outlet of Grouting Pipe should be set along anchor rod anchored section of total length, grouting sequence should since anchor pole end, be segmented from inside to outside according to
It is secondary to carry out.
Anchor cable construction is using as follows:
1) after the intensity of injecting cement paste reaches the 75% of design strength and not less than 15MPa, the tensioning of anchor cable can be carried out
Locking.
2) using the method for the overall tensioning fixation of steel strand wires.
3) anchorage cable stretching should be loaded gently, and loading classification is not preferably greater than 0.3, and the interval time of every grade of load is not less than
3min;Before anchor cable locking, stable a period of time should be kept under maximum stretching force, to sandy soil stratum, stabilization time should be greater than
5min~10min, to cohesive soil stratum, stabilization time should be greater than 15min.
4) anchor cable rope timing, (1.1~1.15) times of the desirable design tensioning lock definite value of tensioning value.
5) in the 48h after anchor cable locking, when anchor cable pulling force is less than design lock value 90%, it should be locked again;
Anchor cable locking is still considered as loss of prestress caused by adjacent anchorage cable stretching locking, when anchor cable pulling force is less than design lock value
When 90%, it should be locked again.
6) anchor cable outer end preferably uses cold cut segmentation method to cut off after locking;Steel strand wires after being cut outside anchorage retain length not
50mm is should be less than, during using thermal cutting, no less than 80mm.
(6), at the top of local excavation's basement periphery soil to second steel waist rail 9.
(7), first time bracing members are set.
Billet 7 is placed above after flattening in the top of engineering pile 8, and first time bracing members withstand on billet 7 by bracing members branch
Blending bolt is fixed in groove.
First time bracing members set depth to be 1.5~2.5m of digging depth positions, and first time bracing members setting spacing is
1.35~3.75m.
(8) soil in the middle of basement, is excavated.
(9), local excavation to basement periphery is native to basement substrate.
(10), second of bracing members 10 are set
Second of bracing members 10 sets two roads.The bracing members of second steel waist rail 9, the steel of first of steel waist rail 2 are first set
It is configured again in the case of the first first time bracing members of dismantling of support, method to set up is set at once after removing first time bracing members
Second of bracing members 10.
Second of bracing members 10 sets depth to be 2~3m of digging depth positions, and second of the setting of bracing members 10 spacing is
1.70~3.83m.
(11) soil in the middle of basement, is excavated.
(12), pour and smash basement bottom board and concrete side walls.Concrete side walls set pre-buried with bracing members junction position
Hole.Embedded water stop rubber strip blocks infiltration path in the middle part of the position basement bottom board of billet 7.
(13), support replacement is set.
Dead slot clogs macadam-aggregate mix between concrete side walls and support pile 1.Macadam-aggregate mix is packed in concrete side walls
Purpose is to make to be converted to the load of bracing members into the evenly load for acting on support pile 1 in dead slot between support pile 1, is
Lower step is removed bracing members and is ready.
Macadam-aggregate mix use rubble, sand grains, powder compound, ballast grain sizes be 15~2mm, quality volume be 30%~
40%;Sand grains particle diameter is 2~0.1mm, and quality volume is 40%~50%;Powder particle diameter is less than 0.1mm, and quality volume is 20%
~30%.
(14) bracing members and billet 7, are removed.
(15) basement roof concrete, is poured.
(16), close that bracing members are pre-buried and the position underplate concrete of billet 7 with water-proof concrete.
From the point of view of the overall process that basement is excavated, maximum soil body deep soil movement is 9mm, and the earth excavation of this engineering is safety
Reliably.