A concrete crack-resistant construction method for the main structure of an open-cut and cast-in-place tunnel

Abstract

The invention belongs to the technical field of tunnel construction, and in particular discloses an anti-cracking construction method for concrete of the main structure of an open-cut and cast-in-place tunnel, which includes the steps of dividing the pouring length, the preparation of crack-resistant concrete, the temperature control step of mold entry, and the construction process control step . The present invention aims at the main contradiction of shrinkage and cracking of the concrete of the main structure of the open-cut and cast-in-place tunnel, from the control of the temperature of the anti-crack concrete (the adiabatic temperature rise of the anti-crack concrete, the mold entry temperature, the maximum temperature rise, the temperature difference between the inside and the outside, the center temperature drop rate, Formwork removal or removal of external insulation measures (temperature difference) and shrinkage deformation (7d self-generated volume deformation and 28d deformation of crack-resistant concrete), put forward the crack resistance control index and implementation plan, and formed a customized package for the main structure of different parts The technical scheme has clear control indicators, strong universality, and simple construction, which can effectively suppress penetrating shrinkage cracks, solve leakage problems, and improve project construction quality.

Description

An anti-cracking construction method for concrete of the main structure of an open-cut and cast-in-place tunnel technical field The invention belongs to the technical field of tunnel construction, specifically, relate to a kind of open-cut cast-in-place tunnel main structure concrete Soil crack resistance construction method. Background technique Although in the field of cut-and-cover cast-in-place tunnel structures, relevant personnel have accumulated many engineering practices, however, concrete The problem of cracking and leakage is still very prominent. Surveys and Research Results Sheets It is clear that most of the leakage is caused by the early shrinkage and cracking of concrete, except for a small part of leakage caused by improper joint treatment. Therefore, solving the early shrinkage and cracking of concrete is the key to controlling the leakage of open-cut and cast-in-place tunnel structures and ensuring the quality of engineering construction. Compare...

Examples

preparation example Construction

[0039] The first is the performance requirements of crack-resistant concrete.

[0043]

[0047] The performance design of the above-mentioned three types of crack-resistant concrete is shown in Table 2 below.

[0049]

[0051] Then there are the requirements for the entry temperature of crack-resistant concrete.

[0066] The above-mentioned anti-cracking construction method of the present invention will be described below through specific construction cases.

Embodiment 1

[0069] First, the pouring length is divided.

[0072] Then, the crack-resistant concrete is prepared and the temperature of the mold is controlled.

[0074] Specifically, one is the performance requirements of crack-resistant concrete.

[0076] According to the consumption shown in the following table 3, the floor concrete, the side wall concrete and the roof concrete are formed by mixing respectively.

[0079]

[0082]

[0083] The second is the requirement for the temperature control of the mold entry of the above-mentioned three types of crack-resistant concrete.

[0087] Finally, the construction technology is controlled from the two aspects of temperature parameter control after the pouring age difference and the anti-cracking concrete pouring.

[0092]

Embodiment 2

[0097] First, the pouring length is divided. This embodiment only involves the pouring project of the tunnel side wall, which is divided into single

[0098] Then, the sidewall concrete was prepared.

[0100] Specifically, one is the performance requirements of the side wall concrete.

[0102] According to the consumption shown in the following table 6, the side wall concrete is formed by mixing respectively.

[0104] Unit: kg / m

[0105]

[0106] The performance of the aforementioned sidewall concrete was tested, and the results are shown in Table 7.

[0108]

[0109] The second is the requirement to control the mold temperature of the above-mentioned sidewall concrete.

[0110] In the specific construction of this embodiment, the construction period from March to April is involved. Average daily air during construction

[0111] Finally, control the construction process.

[0113] The inventor evaluates according to Ruan Zhu Deng Zi No. 1470077 "Analysis Software for Early Crack R...

An anti-cracking construction method for concrete of the main structure of an open-cut and cast-in-place tunnel technical field The invention belongs to the technical field of tunnel construction, specifically, relate to a kind of open-cut cast-in-place tunnel main structure concrete Soil crack resistance construction method. Background technique Although in the field of cut-and-cover cast-in-place tunnel structures, relevant personnel have accumulated many engineering practices, however, concrete The problem of cracking and leakage is still very prominent. Surveys and Research Results Sheets It is clear that most of the leakage is caused by the early shrinkage and cracking of concrete, except for a small part of leakage caused by improper joint treatment. Therefore, solving the early shrinkage and cracking of concrete is the key to controlling the leakage of open-cut and cast-in-place tunnel structures and ensuring the quality of engineering construction. Compare...

Examples

preparation example Construction

[0039] The first is the performance requirements of crack-resistant concrete.

[0043]

[0047] The performance design of the above-mentioned three types of crack-resistant concrete is shown in Table 2 below.

[0049]

[0051] Then there are the requirements for the entry temperature of crack-resistant concrete.

[0066] The above-mentioned anti-cracking construction method of the present invention will be described below through specific construction cases.

Embodiment 1

[0069] First, the pouring length is divided.

[0072] Then, the crack-resistant concrete is prepared and the temperature of the mold is controlled.

[0074] Specifically, one is the performance requirements of crack-resistant concrete.

[0076] According to the consumption shown in the following table 3, the floor concrete, the side wall concrete and the roof concrete are formed by mixing respectively.

[0079]

[0082]

[0083] The second is the requirement for the temperature control of the mold entry of the above-mentioned three types of crack-resistant concrete.

[0087] Finally, the construction technology is controlled from the two aspects of temperature parameter control after the pouring age difference and the anti-cracking concrete pouring.

[0092]

Embodiment 2

[0097] First, the pouring length is divided. This embodiment only involves the pouring project of the tunnel side wall, which is divided into single

[0098] Then, the sidewall concrete was prepared.

[0100] Specifically, one is the performance requirements of the side wall concrete.

[0102] According to the consumption shown in the following table 6, the side wall concrete is formed by mixing respectively.

[0104] Unit: kg / m

[0105]

[0106] The performance of the aforementioned sidewall concrete was tested, and the results are shown in Table 7.

[0108]

[0109] The second is the requirement to control the mold temperature of the above-mentioned sidewall concrete.

[0110] In the specific construction of this embodiment, the construction period from March to April is involved. Average daily air during construction

[0111] Finally, control the construction process.

[0113] The inventor evaluates according to Ruan Zhu Deng Zi No. 1470077 "Analysis Software for Early Crack R...

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