Construction method of ultrahigh large-section concrete frame column
Technical Field
The invention relates to a construction method of a concrete frame column, in particular to a construction method of a concrete frame column with ultrahigh and large cross section.
Background
The concrete column construction adopts the combination of plank sheathing and various scaffold support systems, or adopts finished product steel mould, aluminium mould and various scaffold support systems to make up, needs to set up the scaffold outrigger system in the scaffold support system outside simultaneously, and such way is promptly wasted time and work, and the construction progress is slow, and required support body material is many. When the post is highly surpassing 8 meters, the standard all has higher requirement to setting up of post template and scaffold frame system, outrigger system, and the construction degree of difficulty can be higher simultaneously, needs to go on beyond certain dangerous scheme expert to demonstrate moreover, and is higher to project cost expenditure.
The known methods of constructing ultra-high, large cross-section concrete frame columns therefore suffer from the various inconveniences and problems described above.
Disclosure of Invention
The invention aims to provide a safe and reliable construction method of a concrete frame column with ultrahigh and large cross section.
In order to achieve the purpose, the technical solution of the invention is as follows:
a construction method of a concrete frame column with ultrahigh and large cross section is characterized in that the height of a concrete column exceeds 10 meters, and the cross section of the concrete column exceeds 800mm multiplied by 800mm, and the construction method comprises the following steps:
a. the foundation construction comprises the following steps:
(1) clearing soil, digging to a designed elevation, pouring a concrete cushion layer after a groove is inspected, and placing a bearing platform foundation positioning line;
(2) erecting a one-step formwork of the bearing platform, binding a foundation reinforcing mesh sheet, placing 2 reinforcing split heads on each side of the two-step formwork, and then binding the foundation column reinforcing steel bars;
(3) a corrugated pipe positioning stirrup which is made in advance is placed at the designed position of the foundation column reinforcement cage to prevent the corrugated pipe from displacing;
(4) the lower part of the corrugated pipe is sealed by adopting a special sealing cover, and the corrugated pipe is wound and fixed by using a transparent adhesive tape, so that concrete is prevented from entering and blocking the corrugated pipe;
(5) pouring concrete of a bearing platform and a short column of a foundation at the upper part of the bearing platform, and backfilling the periphery of the bearing platform foundation by adopting well-graded gravels;
(6) positioning and elevation adjustment are carried out before the upper-layer upright post is constructed, the top of the short post is provided with a square timber with the thickness of about 50mm for elevation adjustment, a corrugated pipe protruding out of the top plane part of the short post is cut off, and the opening of the corrugated pipe is temporarily blocked;
b. the construction of the shaped steel upright column template comprises the following steps:
(1) binding a column reinforcement cage, wherein the shape and the size of the processed reinforcement are matched with the specific size of the shaped steel column template;
(2) in the binding process, the longitudinal stress steel bar position of the upright post is required to be consistent with the hole position of the embedded corrugated pipe;
(3) the column body of the upright column is provided with a group of well-shaped positioning ribs every 2 meters, the thickness of the protective layer is controlled, and the error is less than 5 mm;
(4) a hole which is large enough to allow a pump pipe to fall to a column base must be reserved in the middle of the column body reinforcement cage;
(5) the column cap steel bars of the stand column must be strictly lofted according to the inclination of the sizing column template, the inner wall of the sizing column template mold should be cleaned, and an oily release agent is coated;
(6) assembling the column template mould into A, B pieces, firstly, flatly placing the A piece mould on the field, laying square wood below the A piece mould, and hanging the A piece mould into the bound reinforcement cage;
(7) hoisting the B piece of die to close the die, and slowly falling after the bolt holes of the B piece of die and the A piece of die are basically aligned;
(8) when the upright post template mold is fastened by bolts, the fastening should be simultaneously carried out symmetrically from two sides, and each bolt needs to be screwed with two nuts to ensure the fastening;
c. the method for hoisting and pouring the shaped steel upright column template comprises the following steps:
(1) when the shaped steel upright column template falls down during installation, the approximate position of the shaped steel upright column template is adjusted by using a steel wire rope for four directions of a 4-person substation;
(2) wherein 2 persons guide the column-shaped longitudinal steel bar to align to the center of the corrugated pipe, and slowly descend to be in place, so that the steel bar falls into the center of the corrugated pipe;
(3) suspending the shaped steel upright template within 500mm of the falling distance of the short column top surface, performing C60 grouting, enabling the grouting material to fall after being filled, and falling on a steel template skid to enable the steel template skid to be connected with a foundation into a whole;
(4) the steel wire ropes around the steel template fixing tightener at the upper end of the shaped column mould are obliquely pulled and fixed on the ground or floor anchoring tightener for adjusting the verticality of the column mould;
(5) after stabilization, erecting a concrete pump truck, and allowing constructors to climb the ladder stand to the column cap guardrail to pour concrete;
(6) the column reinforcement cage reserves a concrete pouring soil pouring guide pipe falling area with a distance of 150mm in the center position during design. Guiding the concrete to the bottom of the column by using a guide pipe, and ensuring that the free falling height of the concrete is not more than 1.5 m;
(7) the top surface of the column cap (17) has the integral degree not greater than 3 mm;
(8) in order to ensure the appearance quality of the bottom of the column, mortar with the thickness of 50mm and the same mixing ratio as the concrete of the column can be poured before the concrete is poured;
d. dismantling and maintaining the shaped steel upright column template, comprising the following steps:
(1) removing the column formwork after the concrete pouring is finished for 12 hours, wherein the strength of the concrete is not less than 1.2Mpa, and then removing A, B steel column formworks;
(2) when the die bolts are disassembled, the die bolts are symmetrically disassembled from top to bottom, the 2 lowest fastening bolts are reserved, and the die bolts are disassembled after the lifting ropes are tensioned;
(3) the shaped steel column template mould is separated towards two sides and is lifted away from the column in the horizontal direction, a steel wire rope is adopted to stabilize the mould, the mould cannot collide with the column, the mould is symmetrically disassembled when the column mould is jacked open, force is slowly applied, a pry bar is used for assisting, and steel wedges are adopted to loosen if necessary;
(4) and after the mould is dismantled, the mould is lifted to a specified stacking place, and is immediately cleaned and maintained, and the concrete is maintained by spraying water through a high-pressure sprayer.
The construction method of the concrete frame column with ultrahigh and large section can be further realized by adopting the following technical measures.
The method, wherein the column reinforcement cage comprises column longitudinal stress reinforcements and stirrups.
The method, wherein the verticality of the column formwork is adjusted within 5 mm.
After the technical scheme is adopted, the construction method of the concrete frame column with ultrahigh and large cross section has the following advantages:
1. the hoop type two-piece upright post template has simple structure and convenient manufacture;
2. the engineering quality is safe and reliable, and the formwork of the concrete frame column is fast and efficient;
3. the labor efficiency of workers is improved, the engineering measure cost is greatly reduced, and the construction period is shortened.
Drawings
FIG. 1 is a block diagram of a concrete frame column construction process according to an embodiment of the present invention;
FIG. 2 is a schematic diagram of the structure of the base and upper columns according to the embodiment of the present invention;
FIG. 3 is a cross-sectional view A-A of FIG. 2;
fig. 4 is a cross-sectional view of B-B in fig. 2.
In the figure: 1A steel column template; 2B, a steel template; 3 fastening bolts by using a steel mould; 4, wood-cushioned plate of steel template; 5 phi 60 corrugated pipe (length not less than buried depth + 50); 6 ground or floor anchoring tightener; 7, steel wire ropes; 8, fixing a wire tightener by a steel template; 9, a guardrail type ladder stand; 10, protecting the fence; 11 column stirrups; 12 column longitudinal stress steel bar; 13 positioning the steel plate; 14 foundation vertical reinforcing steel bars; 15 basic hooping; 16 base steel bars; 17 a cap; 18 cap rebar, 19 stub.
Detailed Description
The present invention will be further described with reference to the following examples and the accompanying drawings.
Example 1
Fig. 1 is a block diagram of a concrete frame column construction process flow according to an embodiment of the present invention. The construction method of the concrete frame column with the ultrahigh and large cross section simplifies the construction procedures in the steel column formwork construction process and reduces the construction difficulty of the ultrahigh frame column.
Referring now to fig. 2 to 4, the construction method of the ultra-high, large-section concrete frame column of the present invention includes the steps of:
1. construction of foundations
1) Firstly, clearing soil and digging to a designed elevation, pouring a concrete cushion layer after a groove is inspected, and placing a bearing platform foundation positioning line.
2) The method comprises the steps of erecting a template of a first bearing platform, binding 16 meshes of foundation steel bars, placing 2 steel bar split heads on each side of a second bearing platform, and binding the foundation column steel bars.
3) The corrugated pipe positioning stirrup which is made in advance is placed at the designed position of the foundation column steel reinforcement cage, so that the corrugated pipe is prevented from displacing.
4) The lower part of the corrugated pipe 5 is sealed by adopting a special sealing cover and is wound and fixed by transparent adhesive tape, so that concrete is prevented from entering the pipe to block the corrugated pipe.
5) Pouring bearing platform concrete, then carrying out template installation of the short column, pouring short column concrete after the short column concrete is finished, and backfilling the periphery of the bearing platform foundation by adopting sand stones with good gradation. The short column is a short rectangular concrete column on the upper part of the bearing platform, and the short column, the bearing platform and the pile foundation form a foundation together. Stub and pillar relationship: the short column is a basic part, the upright column is an upper structure part, and the upright column is positioned and mounted at the upper part of the short column according to the drawing.
6) Positioning and elevation adjustment are well carried out before the construction of the upper-layer stand column, the elevation of the thick square timber is adjusted about 50mm at the top of the short column, the corrugated pipe which protrudes out of the plane part of the top of the short column is cut off, and the pipe orifice is temporarily blocked.
2. Shaped steel column formwork construction
1) Binding a column reinforcement cage (comprising column longitudinal stress reinforcements 12 and stirrups 11), wherein the shape and the size of the reinforcement processing are matched with the size of a shaping column mould body.
2) In the binding process, the position of the longitudinal stressed steel bar of the column is required to be consistent with the position of the pre-buried corrugated pipe hole 5.
3) The column body is provided with a # -shaped positioning rib, each 2m of the column body is provided with a group of positioning ribs, the thickness of the protective layer is controlled, and the error is less than 5 mm.
4) The middle of the column body reinforcement cage must be reserved with a hole large enough for the pump pipe to fall to the column base.
5) The column cap reinforcing steel bars 18 must be strictly lofted according to the inclination of the sizing column mold, the inner wall of the sizing column mold should be cleaned, and an oily release agent is coated.
6) The die is assembled by A, B pieces, the A piece die 1 is flatly placed on the ground, the square wood is padded on the lower part, and the A piece die is hung into the bound reinforcement cage (the column-containing longitudinal stress reinforcement 12 and the stirrup 11).
7) And hoisting the B piece of die 2 to close the die, and slowly falling after the holes of the bolts 3 of the B piece of die and the A piece of die are basically aligned.
8) The bolts 3 should be fastened symmetrically from both sides at the same time, and two nuts must be screwed for each bolt to ensure fastening.
3. Shaped column formwork hoisting and concrete pouring
1) When the shaping column die is installed and falls down, the approximate position of the shaping column die is adjusted by a steel wire rope for four directions of the 4-person substation.
2) Wherein 2 people guide the vertical reinforcing bar 12 of post style of calligraphy to aim at the bellows 5 center, slowly descend to take one's place, make the reinforcing bar fall into bellows central point and put.
3) The sizing column mold is suspended within 500mm of the falling distance of the top surface of the short column, C60 grouting is carried out, and the grouting material falls after being filled, falls on the steel template skid 4, and is connected with the foundation into a whole.
4) And the steel wire ropes 7 around the steel template fixing tightener 8 at the upper end of the sizing column die are obliquely pulled and fixed on the ground or floor anchoring tightener 6 for adjusting the verticality of the column die and controlling the verticality within 5 mm.
5) After stabilization, a concrete pump truck is erected, and constructors climb to the column cap guardrail 10 along the crawling ladder 9 to pour concrete.
6) When the column reinforcement cage (comprising the column longitudinal stress reinforcement 12 and the stirrup 11) is designed, a concrete pouring soil pouring guide pipe falling area with the distance of 150mm is reserved in the center position. And guiding the concrete to the bottom of the column by using a guide pipe to ensure that the free falling height of the concrete is not more than 1.5 m.
7) The surface flatness of the joint of the top surface of the column cap 17 and the upper beam thereof is not more than 3 mm. The column cap is positioned on the column top surface and enlarges the section part of the column, just like the upper part of the column is 'a cap'. The column cap steel bars and the column steel bars are bound simultaneously, and because the section of the column cap is larger than that of the column, stressed steel bars are respectively inserted into the top of the column in a direction perpendicular to the longitudinal direction and the transverse direction of the column, corresponding distributed steel bars are arranged in the direction perpendicular to the stressed steel bars to form a steel bar mesh with the enlarged section of the column, and finally the steel bar mesh and the column are placed into a finished steel column die together along with the column to be poured with concrete.
8) In order to ensure the appearance quality of the column bottom, mortar with the thickness of 50mm and the same strength can be poured before concrete is poured.
4. Column form demolition and maintenance
1) And (3) removing the column formwork after the concrete is poured for 12 hours, wherein the strength of the concrete is not less than 1.2Mpa, and then A, B steel column formworks 1 and 2 can be removed.
2) When the bolts are disassembled, the bolts are symmetrically disassembled from top to bottom, the 2 fastening bolts (3) at the bottom are reserved, and the lifting ropes are disassembled after being tensioned.
3) The mould separates to both sides, hangs from the post horizontal direction and leaves, adopts wire rope stable mould, must not collide the post. When the column mould is jacked open, the column mould is symmetrically dismantled, slowly applied with force, assisted by a pry bar, and loosened by adopting a steel wedge if necessary.
4) And after the mould is dismantled, the mould is lifted to a specified stacking place, and is immediately cleaned and maintained, and the concrete is maintained by spraying water through a high-pressure sprayer.
The positioning steel plate 13 is mainly installed at the bottom of the foundation bearing platform and the bottom of the short column at the upper part of the foundation bearing platform and is positioned on the foundation bearing platform and the steel bars of the short column by welding for fixing the four-corner steel bars of the bottom upright column and the four-corner steel bars in the foundation.
The above embodiments are provided only for illustrating the present invention and not for limiting the present invention, and those skilled in the art can make various changes or modifications without departing from the spirit and scope of the present invention. Accordingly, all equivalents are intended to fall within the scope of the invention, which is defined in the claims.