CN103711131A

CN103711131A - Ultra-soft soil large-area deep foundation pit guard post support changing method

Info

Publication number: CN103711131A
Application number: CN201310727817.4A
Authority: CN
Inventors: 李佳; 翟强; 贲林; 颜廷丰; 刘宏宇
Original assignee: Sixth Engineering Co Ltd of China Railway 13th Bureau Group Co Ltd
Current assignee: Sixth Engineering Co Ltd of China Railway 13th Bureau Group Co Ltd
Priority date: 2013-12-26
Filing date: 2013-12-26
Publication date: 2014-04-09

Abstract

The invention provides an ultra-soft soil large-area deep foundation pit guard post support changing method, and belongs to the technical field of construction. The method includes the steps of firstly, welding and fixing steel corbels and an embedded board, fixedly connecting a fixed end, a middle rod and a movable end to form a supporting rod, and embedding and fixing the supporting rod between the corbels; secondly, connecting and fixing the two ends of each I-beam to end plates, and embedding and fixing the I-beams and the end plates to the two ends of rear pouring belts or the middle portion of a floor or the middle portion of a wall; thirdly, conducting construction of a first concrete belt after the first step and the second step are completed, and then conducting backfilling of graded sand and stone and construction of a second concrete belt; fourthly, detaching an inner support after the first step, the second step and the third step are completed; fifthly, repeatedly executing the steps to conduct support changing of corresponding floors if a plurality of inner supports are arranged on a guard post. The ultra-soft soil large-area deep foundation pit guard post support changing method has the advantages that the uniformity of force transmission of the graded sand and stone, the strength of the concrete structure and the advantages that the steel structure is high in splicing speed and high in efficiency are simultaneously used for conducting inner support change of foundation pit supporting, the influences of the inner supports on structure construction are eliminated, project quality is improved, and the operation is easy to conduct.

Description

A kind of ultra-soft soil property large-area deep foundation pit fender post support replacement method

Technical field

The invention belongs to technical field of building construction.

Background technology

At present, drill-pouring inner support of pile is that more a kind of combined supporting form is applied in China's Coastal Areas, particularly for the excavation of soft clay area large-area deep foundation pit, inner support system can be according to foundation ditch shape independent assortment, and can bring into play good pattern foundation pit supporting structure effect.But, inner support has a very large drawback, be that very large obstacle has been manufactured in the follow-up construction of existing for of inner support, before follow-up construction, must process inner support, make construction have to stop herein, form constuction joint, both affected the progress of construction, affected again the quality of construction.

Summary of the invention

The object of the invention is: a kind of ultra-soft soil property large-area deep foundation pit fender post support replacement method is provided, and it can realize the stressed conversion of fender post inner support and structure self, and simple to operate, easily capable.

Method of the present invention is:

1, steel corbel and buried plate are welded and fixed, fixed end, king-rod, movable end are connected and fixed from the flanged bolt that carries out by end, form strut, strut is mounted between bracket.

2, i iron two ends and end plate are welded to connect fixing, are then mounted in two ends, ater-casting, floor or body of wall middle part; Equipment box out place i iron span centre 1-4 root setting up and down reinforcing bar carry out cross-cut.

3, after above-mentioned " 1 ", " 2 " step complete, carry out the construction of first concrete belt, after it reaches concrete design strength, carry out the backfill of graded sand and stone and the construction of second concrete belt, the absolute altitude of concrete belt is identical with floor absolute altitude, and thickness is identical with slab thickness.

4, until above-mentioned " 1 ", " 2 ", " 3 " step complete and structure self concrete strength reach design strength 80% after, carry out the dismounting of inner support.

If 5 fender posts have multiple tracks inner support, can repeat the step of " 1 ", " 2 ", " 3 " " 4 " and carry out the support replacement of respective storey.

Steel pipe diagonal brace angle is between 40-50 °.

Adopt aggregate grading ratio to be:

Component title	Particle diameter (mm)	Content (%)
			Rubble	2-15	30-40
Sand grains	0.1-2	40-50
			Powder	<0.1	10-20

The invention has the beneficial effects as follows: utilize the uniformity of graded sand and stone power transmission and the intensity of concrete structure itself, utilize the advantage that steel structure assembling speed is fast, efficiency is high to carry out the inner support conversion of pattern foundation pit supporting structure simultaneously, eliminated the impact of inner support on structure construction, improved workmanship, and operated simply, easily go.

Accompanying drawing explanation

Fig. 1 is support replacement layout plan of the present invention;

Fig. 2 is A-A sectional drawing of the present invention;

Fig. 3 is B-B sectional drawing of the present invention;

Fig. 4 is C-C sectional drawing of the present invention.

The specific embodiment

Embodiment 1

Below in conjunction with accompanying drawing, the present invention is described further:

As shown in the figure, the 1st, steel corbel, the 2nd, fixed end, the 3rd, king-rod, the 4th, movable end, the 5th, buried plate, the 6th, concrete belt, the 7th, graded sand and stone, the 8th, i iron, the 9th, end plate, the 10th, reinforcing bar, the 11st, fender post, the 12nd, equipment boxes out, the 13rd, ater-casting, the 14th, B1, the 15th, underground two layers.

Steel corbel 1 adopts Plate Welding to form, and fixed end 2, king-rod 3, movable end 4 main bodys adopt steel pipe, and diagonal brace angle is 40-50 degree.Its concrete implementation step is as Figure 1-4:

1, steel corbel 1 and buried plate 5 are welded and fixed, fixed end 2, king-rod 3, movable end 4 are carried out to bolt connection by end from flanged, form strut, strut is mounted between bracket.

2, i iron 8 two ends and end plate 9 are welded to connect, are then mounted in 13 two ends, ater-casting, floor or body of wall middle part; Box out span centre two reinforcing bars 10 setting up and down of 12 place's i iron 8 of equipment carry out cross-cut, guarantee the stable of i iron.

3, after " 1 ", " 2 " step complete, carry out the construction of first concrete belt 6, after it reaches concrete design strength, carry out the backfill of graded sand and stone 7 and the construction of second concrete belt 6, the absolute altitude of concrete belt 6 is identical with floor absolute altitude, the same slab thickness of thickness.

4, until " 1 ", " 2 ", " 3 " step complete and structure self concrete strength reach design strength 80% after, carry out the dismounting of inner support.

By said method, can successfully realize the stressed conversion of ultra-soft soil property large-area deep foundation pit fender post inner support and structure self.

Claims

1. a ultra-soft soil property large-area deep foundation pit fender post support replacement method, its method is:

A, steel corbel and buried plate are welded and fixed, fixed end, king-rod, movable end are connected and fixed from the flanged bolt that carries out by end, form strut, strut is mounted between bracket;

B, i iron two ends and end plate are welded to connect fixing, are then mounted in two ends, ater-casting, floor or body of wall middle part; Equipment box out place i iron span centre 1-4 root setting up and down reinforcing bar carry out cross-cut;

C, after above-mentioned a, b step complete, carry out the construction of first concrete belt, after it reaches concrete design strength, carry out the backfill of graded sand and stone and the construction of second concrete belt, the absolute altitude of concrete belt is identical with floor absolute altitude, and thickness is identical with slab thickness;

D, until above-mentioned a, b, c step complete and structure self concrete strength reach design strength 80% after, carry out the dismounting of inner support;

If e fender post has multiple tracks inner support, the step that can repeat a, b, c, d is carried out the support replacement of respective storey.

2. a kind of ultra-soft soil property large-area deep foundation pit fender post support replacement method as claimed in claim 1, is characterized in that: steel pipe diagonal brace angle is between 40-50 °.

3. a kind of ultra-soft soil property large-area deep foundation pit fender post support replacement method as claimed in claim 1, is characterized in that:

Adopt aggregate grading ratio to be

The rubble of 2-15 mm is 30-40%;

The sand grains of 0.1-2 mm is 40-50%;

The powder of <0.1 mm be 10-20%.