CN-118125776-B - Open-closed cell control type electromagnetic protection concrete

CN118125776BCN 118125776 BCN118125776 BCN 118125776BCN-118125776-B

Abstract

The invention relates to an open-closed cell control type electromagnetic protection concrete, which is foam concrete, wherein a foam concrete is prepared by adding a foam stabilizer and a foaming agent into a formula, the foam concrete has an open-cell structure and a closed-cell structure, the foam concrete comprises a cationic surfactant Cetyl Trimethyl Ammonium Bromide (CTAB), a nonionic surfactant Triton X-100 (TX-100), a nonionic surfactant Tween 60 (T60) and an anionic surfactant dodecyl sodium sulfate (SDS), the proportion of the Cetyl Trimethyl Ammonium Bromide (CTAB), the Triton X-100, the dodecyl sodium sulfate (SDS) and the Tween 60 is regulated to control the open-closed cell control type electromagnetic protection concrete, and then the electromagnetic wave reflection loss of the open-closed cell control type electromagnetic protection concrete is regulated, so that the free regulation of the reflection loss of specific electromagnetic waves is realized.

Inventors

LIU XIONGFEI
GUO YONGLING
HAO YIFEI
WANG XIAOZHONG
MA GUOWEI

Assignees

河北工业大学

Dates

Publication Date: 20260505
Application Date: 20240327

Claims (7)

1. The open-closed cell control type electromagnetic protection concrete is characterized in that the open-closed cell control type electromagnetic protection concrete is foam concrete, a foam stabilizer and a foaming agent are added in the formula, the mass of the foam stabilizer is 35-72% of that of the foaming agent, and the foam concrete is provided with an open cell structure and a closed cell structure, wherein the foam stabilizer comprises cetyl trimethyl ammonium bromide CTAB, TX-100, tween T60 and dodecyl sodium sulfate SDS; The mass of TX-100 is 160% -200% of that of cetyl trimethyl ammonium bromide CTAB, and the mass of Tween T60 is 20% -25% of that of dodecyl sodium sulfate SDS; The aperture ratio of the open-close pore control type electromagnetic protection concrete is controlled by regulating and controlling the proportion of cetyl trimethyl ammonium bromide CTAB, TX-100, dodecyl sodium sulfate SDS and Tween T60, so that the electromagnetic wave reflection loss of the open-close pore control type electromagnetic protection concrete is regulated and controlled, and the free regulation of the reflection loss of electromagnetic waves in a specific wave band is realized.
2. The open-close cell controlled electromagnetic shield concrete according to claim 1, wherein, Cetyl trimethylammonium bromide CTAB is used to form an open cell structure; Sodium dodecyl sulfate, SDS, is used to form closed cell structures; TX-100 was used to control the stability of cetyltrimethylammonium bromide CTAB and Tween T60 was used to control the stability of sodium dodecyl sulfate SDS; The proportion of cetyltrimethylammonium bromide CTAB and dodecyl sodium sulfate SDS is adjusted to adjust the aperture ratio of the open-closed pore control type electromagnetic protection concrete.
3. The open-closed cell control type electromagnetic protection concrete according to claim 1, wherein the composition of the open-closed cell control type electromagnetic protection concrete comprises Portland cement, fly ash, slag micropowder, foaming agent, foam stabilizer, water reducing agent, accelerator and water, the mass ratio of the fly ash, the Portland cement and the slag micropowder is that the fly ash is common Portland cement, the slag micropowder=2:3:1, the mass of the foaming agent is 4-11% of the mass of the water, and the concrete preparation process comprises: Uniformly mixing ordinary Portland cement, fly ash and slag micropowder to obtain a dry mixture; Adding water into the dry mixture while stirring at the speed of 80-100rpm/min to form a viscous gel, wherein the mass ratio of the water to the dry mixture is 0.5-0.55:1; Then, after the water reducer and the accelerator are sequentially put into the reactor, stirring is started at the speed of 280-350rpm/min until the mixture becomes uniform and flowable mixed slurry; Finally, adding a foaming agent into the mixture slurry, adding a foam stabilizer, and continuously stirring at the speed of 280-350pm/min to obtain the open-closed pore control type electromagnetic protection concrete; The mixing mode of the foam stabilizer is that four foam stabilizers are mixed and fully stirred to ensure the uniformity of the mixture, then the mixed foam stabilizers are gradually injected into cement slurry, and continuously stirred in the injection process to ensure uniform distribution, so that the condition of local foam stabilizer concentration or nonuniform distribution in concrete is prevented, and the performance and quality of the concrete are ensured.
4. The open-closed pore control type electromagnetic protection concrete according to claim 1, wherein the water reducer is at least one of a naphthalene-based high-efficiency water reducer, an aliphatic high-efficiency water reducer, an amino high-efficiency water reducer and a polycarboxylic acid high-performance water reducer, and the addition amount is 1-2% of the mass of water; The accelerator is an alkali-free accelerator taking sulfuric acid alumina as a main component, and the mass of the accelerator is 3-4% of the mass of water, so that the mixed slurry is immediately coagulated and hardened after foaming, and meanwhile, the mixed slurry keeps good fluidity before and during foaming; The foaming agent is hydrogen peroxide or vegetable protein.
5. The open-closed cell controlled electromagnetic protection concrete according to claim 3, wherein foaming agents with different masses are added, foam concrete with the density of 400-1200 kg/m 3 is manufactured, the density of the foam concrete is gradually reduced along with the addition of the foaming agents, the porosity is gradually increased within the range of 37% -72%, and the effective absorption loss peak value is increased firstly and then reduced along with the increase of the density, so that the electromagnetic absorption loss control of different peak values of a specific wave band is realized.
6. An open-close cell controlled electromagnetic shield concrete according to claim 3, wherein the specific rules for the free adjustment of the reflection loss of electromagnetic waves of a specific wavelength band are: When the effective absorption wave band of the target is 1.0-5.0 GHz, the aperture ratio corresponding to the open-closed pore control type electromagnetic protection concrete is 4%; When the effective absorption wave band of the target is 5.0-11.0 GHz, the aperture ratio corresponding to the open-closed pore control type electromagnetic protection concrete is 30%; When the effective absorption wave band of the target is 11.0-14.0 GHz, the aperture ratio corresponding to the open-closed pore control type electromagnetic protection concrete is 77%; When the effective absorption wave band of the target is 14.0-18.0 GHz, the aperture ratio corresponding to the open-closed pore control type electromagnetic protection concrete is 98%; The effective absorption wave band and the corresponding aperture ratio are expressed in the form of data points, and if the effective absorption wave band is not in the range or is crossed with the range, the aperture ratio of any given absorption wave band is calculated according to a linear interpolation mode, and the specific process is as follows: taking any given effective absorption band as a target band, finding two known data points closest to the initial value of the target band aiming at the target band, calculating the aperture ratio corresponding to the target band by using a linear interpolation formula, and specifically calculating the aperture ratio by the following steps: Let the known near target band data points be (f 1 , r 1 ) and (f 2 , r 2 ), where f 1 and f 2 represent band initial values, respectively, and r 1 and r 2 represent corresponding open cell ratios, respectively, for the target band initial value f t , the corresponding open cell ratio r t is calculated using a linear interpolation formula as: r t = r 1 + (f t - f 1 ) / (r 2 - r 1 ) × (f 2 - f 1 ).
7. The open-closed cell controlled electromagnetic shield concrete according to claim 6, wherein the open-cell controlled electromagnetic shield concrete has an open-cell ratio controlled by controlling the proportions of cetyltrimethylammonium bromide CTAB, TX-100, sodium dodecyl sulfate SDS and tween T60, and comprises the following specific procedures: Setting dodecyl sodium sulfate SDS and cetyl trimethyl ammonium bromide CTAB with a mass ratio of 5:0, and obtaining open-closed pore control type electromagnetic protection concrete with an opening ratio of 1% -25%; setting dodecyl sodium sulfate SDS and cetyl trimethyl ammonium bromide CTAB with a mass ratio of 15:1, and obtaining open-closed pore control type electromagnetic protection concrete with an opening ratio of 26% -50%; Setting dodecyl sodium sulfate SDS and cetyl trimethyl ammonium bromide CTAB with a mass ratio of 10:3, and obtaining open-closed pore control type electromagnetic protection concrete with an opening ratio of 51% -79%; and setting the mass ratio of dodecyl sodium sulfate SDS to cetyl trimethyl ammonium bromide CTAB to be 0:4, and obtaining the open-closed pore control type electromagnetic protection concrete with the aperture ratio of 80% -99%.

Description

Open-closed cell control type electromagnetic protection concrete Technical Field The invention belongs to the technical field of novel building electromagnetic protection materials, and particularly relates to open-closed pore control type electromagnetic protection concrete. Background With the widespread use of electromagnetic wave technology, new rounds of pollution have also resulted in electronic devices that may leak private information or be affected by other electromagnetic interference during operation. Whether electromagnetic waves can harm living environment and human health is always a very interesting topic. Therefore, research on electromagnetic absorption or electromagnetic shielding techniques is indispensable. Compared with the conventional common coating wave-absorbing material, the cement-based wave-absorbing material can avoid the defects of easy oxidation and falling, poor durability and the like. Carbon black, carbon fiber and carbon nano tube are used as absorbent, so that the electromagnetic wave absorption performance of the concrete can be further enhanced. Similar to EPS, EP, GP, hollow glass beads (HGM) and other porous materials, the pore structure in the foam cement-based material can also improve the impedance matching performance and the electromagnetic wave loss capacity, but the pore structure of the existing foam cement-based material is generally uncontrollable, and the electromagnetic wave absorption effect is poor, so the application provides novel electromagnetic protection concrete, which regulates and controls the internal microstructure in the cement-based material, so that the preparation process is simple, the cost is reduced, the effective absorption loss of a specific wave band can be realized through reasonable open-closed pore structure design, and the better strength requirement can be met. Disclosure of Invention The invention provides open-closed pore control type electromagnetic protection concrete based on modern electromagnetic protection requirements, and the free adjustment of the reflection loss of electromagnetic waves in a specific frequency band is realized within the range of 1-18 GHz by adjusting the aperture ratio of foam concrete. In order to achieve the above purpose, the invention adopts the following technical scheme: The open-closed cell control type electromagnetic protection concrete is foam concrete, wherein a foam stabilizer and a foaming agent are added in the formula, the mass of the foam stabilizer is 35-72% of that of the foaming agent, and the foam concrete is provided with an open-cell structure and a closed-cell structure, and the foam stabilizer comprises a cationic surfactant Cetyl Trimethyl Ammonium Bromide (CTAB), a nonionic surfactant Triton X-100 (TX-100), a nonionic surfactant Tween 60 (T60) and an anionic surfactant Sodium Dodecyl Sulfate (SDS); The aperture ratio of the open-closed cell control type electromagnetic protection concrete is controlled by regulating and controlling the proportion of Cetyl Trimethyl Ammonium Bromide (CTAB), triton X-100, sodium Dodecyl Sulfate (SDS) and Tween 60, so that the electromagnetic wave reflection loss of the open-closed cell control type electromagnetic protection concrete is regulated and controlled, and the free regulation of the reflection loss of electromagnetic waves in a specific wave band is realized. Further, the cationic surfactant is used to form an open cell structure; anionic surfactants are used to form closed cell structures; The nonionic surfactant is used for reducing the total surfactant usage amount, improving the foam stability, TX-100 is used for controlling the CTAB stability, and T60 is used for controlling the SDS stability; The mass of TX-100 is 160% -200% of that of CTAB, and the mass of T60 is 20% -25% of that of SDS; The proportion of CTAB and SDS is regulated to regulate the aperture ratio of the open-closed pore control type electromagnetic protection concrete. Further, the composition of the open-closed pore control type electromagnetic protection concrete comprises Portland cement, fly ash, slag micro powder, a foaming agent, a foam stabilizer, a water reducing agent, an accelerator and water, wherein the mass ratio of the fly ash to the Portland cement to the slag micro powder is 4-11% of the mass of the water, the mass ratio of the fly ash to the Portland cement to the slag micro powder is 2:3:1, and the concrete preparation process comprises the following steps: Uniformly mixing ordinary Portland cement, fly ash and slag micropowder to obtain a dry mixture; Adding water into the dry mixture while stirring at the speed of 80-100rpm/min to form a viscous gel, wherein the mass ratio of the water to the dry mixture is 0.5-0.55:1; Then, after the water reducer and the accelerator are sequentially put into the reactor, stirring is started at the speed of 280-350rpm/min until the mixture becomes uniform and flowable mixed slurry; Finally, adding a foaming