CN112309514B

CN112309514B - Mountain sand concrete mix proportion design method with fluctuating mud content

Info

Publication number: CN112309514B
Application number: CN202011213936.4A
Authority: CN
Inventors: 张彦; 李红辉; 蔡俊华; 卢坤鹏; 高礼雄; 宋作宝; 高春勇; 吴浩
Original assignee: Guangdong Changda Experimental Technology Development Co ltd
Current assignee: Guangdong Changda Experimental Technology Development Co ltd
Priority date: 2020-11-04
Filing date: 2020-11-04
Publication date: 2022-03-18
Anticipated expiration: 2040-11-04
Also published as: CN112309514A

Abstract

A design method of a mixing proportion of mountain sand concrete with fluctuating mud content comprises the steps of firstly determining the mud content fluctuation range of mountain sand for concrete according to a GB/T14684 test method of building sand; designing additive components by taking the average mud content of the mountain sand and the corresponding sand rate of the mountain sand as references, and calculating and determining the design parameters of the average mud content reference mountain sand concrete mix proportion by adopting a mass method according to the specification of JGJ 55 in the design rule of common concrete mix proportion; and then calculating and determining the corresponding sand rate of the mountain sand concrete with the mud content on site in a mode that the sand rate is reduced by 1% when the mud content is increased by 1% or the sand rate is increased by 1% when the mud content is reduced by 1% on the basis of the average mud content of the mountain sand, and then calculating and determining the design parameters of the mix proportion of the mountain sand concrete. On the premise of ensuring that the working performance of the mountain sand concrete with fluctuation of the mud content meets the design requirement, the invention solves the technical problem of adaptability of the admixture and the mountain sand with fluctuation of the mud content, and provides a new design method for the mix proportion design of the mountain sand concrete with fluctuation of the mud content.

Description

Mountain sand concrete mix proportion design method with fluctuating mud content

Technical Field

The invention relates to the technical field of building materials, in particular to a mountain sand concrete mixing proportion design method with fluctuating mud content.

Background

At present, the replacement of natural sand by machine-made sand has become a necessary trend in the development of concrete materials. The mountain sand is one type of machine-made sand, in particular to rock particles with nominal particle size less than 5.00mm, which are prepared by carrying out soil removal mining, mechanical crushing and screening on carbonate rock. The mud content of the sand and the inadaptability of the additive have adverse effect on the fluidity of the concrete, so the mud content of the machine-made sand is specified in the building sand GB/T14684 standard: less than 1.0% of class I, less than 3.0% of class II and less than 5.0% of class III. The control of the mud content of the sand by a washing mode is a technical approach for preparing concrete, but secondary environmental pollution can be caused by sand washing, and new adverse effects can be generated on the working performance of the concrete by a polyacrylamide flocculant remained in the washed sand. The actual sand used in engineering has a general phenomenon that the mud content exceeds 5 percent and the mud content fluctuation is very large, so that serious inadaptability exists between the admixture and the mountain sand, and the initial slump and the slump loss of the concrete are extremely difficult to control.

At present, scholars in China put forward technical measures of using a mud-resistant polycarboxylate superplasticizer and a mud-blocking agent, and try to solve the problem of adaptability of an additive and mud-content fluctuation sand, but the effect is not obvious. There have also been proposals to increase the amount of water used per unit, but this method has some improvement, but results in increased concrete costs. The research finds that: the mud in the sand has an adverse effect on the fluidity of the concrete, but improves the cohesiveness of the concrete. The wrapping property of the concrete is deteriorated at a low sand rate, and the wrapping property of the concrete can be improved by increasing the mud content in this case; the cohesiveness of the concrete becomes large at a high sand ratio, and in this case, the decrease in the content of sludge improves the cohesiveness of the concrete. Therefore, through reasonable selection of the mud content of the sand and the corresponding sand rate, the design of the components of the admixture and the design of the mixing ratio of the mud content fluctuation sand concrete are carried out, so as to solve the problem of inadaptability between the admixture and the mud content fluctuation sand.

Disclosure of Invention

The invention aims to solve the technical problem of adaptability of a concrete admixture and mountain sand with fluctuation of mud content, and provides a mountain sand concrete mixing proportion design method with fluctuation of mud content.

The purpose of the invention is realized by the following technical scheme.

A design method of a mixing proportion of mountain sand concrete with fluctuating mud content comprises the following steps:

(1) limiting the fluctuation range of the mud content of the mountain sand for concrete, and requiring:

when the strength grade of the mountain sand concrete is C20-C35, the fluctuation range of the mud content of the mountain sand is 1.0-6.0%;

when the strength grade of the mountain sand concrete is C40-C50, the fluctuation range of the mud content of the mountain sand is 1.0-4.0%;

(2) calculating the average mud content of the mountain sand by using the mud content fluctuation range, and determining the sand rate corresponding to the mountain sand concrete by using the average mud content as a reference: firstly, determining the sand rate beta corresponding to the mud content of 0 percent according to the fineness modulus of the sand_sThen, the sand rate beta corresponding to the average mud content is calculated and determined in a mode that every time the mud content is increased by 1 percent, the sand rate is reduced by 1 percent^/ _s；

Taking the average mud content of the mountain sand and the corresponding sand rate beta^/ _sDesigning additive components as a reference, and calculating and determining the design parameters of the mixing ratio of the mountain sand concrete under the reference condition of average mud content by adopting a mass method: cement dosage m_c0The amount of the fly ash m_f0The amount of the mineral powder m_k0Sand dosage m_s0Amount of stone m_g0Water consumption m_w0The dosage m of the admixture_a0；

(3) Testing to determine the mud content of the mountain sand on site, calculating the difference n% from the average mud content, and calculating the sand rate beta corresponding to the mountain sand concrete according to the mode that the sand rate is reduced by 1% when the mud content is increased by 1% on the basis of the average mud content of the mountain sand^/ _s-n%, calculating the design parameters of the mix proportion of the sand concrete according to the following rules: cement dosage m^/ _c0＝m_c0The amount of the fly ash m^/ _f0＝m_f0The amount of the mineral powder m^/ _k0＝m_k0Sand dosage m^/ _s0＝(β^/ _s-n％)×(m_s0+m_g0) Amount of stone m^/ _g0＝(m_s0+m_g0-m^/ _s0) Water for useQuantity m^/ _w0＝m_w0The dosage m of the admixture^/ _a0＝m_a0；

Or calculating the sand rate beta corresponding to the mountain sand concrete on site by taking the average mud content of the mountain sand as a reference and increasing the sand rate by 1% when the mud content is reduced by 1%^/ _s+ n%, calculating the design parameters of the mixing proportion of the mountain sand concrete according to the following rules: cement dosage m^/ _c0＝m_c0The amount of the fly ash m^/ _f0＝m_f0The amount of the mineral powder m^/ _k0＝m_k0Sand dosage m^/ _s0＝(β^/ _s+n％)×(m_s0+m_g0) Amount of stone m^/ _g0＝(m_s0+m_g0-m^/ _s0) Water consumption m^/ _w0＝m_w0The dosage m of the admixture^/ _a0＝m_a0。

As the limitation to the technical scheme, the method for testing the mud content of the mountain sand adopts a GB/T14684 test method of building sand.

As the limitation of the technical scheme, the method for determining the sand rate corresponding to the mud content of 0% by the mountain sand fineness modulus in the step (2) and the method for determining the design parameters of the mountain sand concrete mix proportion under the average mud content reference condition adopt the specification of JGJ 55 in the general concrete mix proportion design rule.

As a limitation to the technical scheme, the step (2) comprises the following components in parts by mass per thousand of the additive:

when the strength grade of the mountain sand concrete is C20-C35: 220-280 parts of polycarboxylic acid water-reducing master batch with solid content of 40%, 150-180 parts of polycarboxylic acid slump-retaining master batch with solid content of 40%, 5-15 parts of sodium gluconate, 5-15 parts of white sugar, 0.1-0.2 part of sodium dodecyl benzene sulfonate and 0.5-0.6 part of xanthan gum; 1.0-1.5 parts of hydroxyethyl methyl cellulose ether, 0.1-0.2 part of an organic silicon defoamer and the balance of water;

when the strength grade of the mountain sand concrete is C40-C50: 320-400 parts of polycarboxylic acid water-reducing master batch with the solid content of 40%, 200-250 parts of polycarboxylic acid slump-retaining master batch with the solid content of 40%, 5-15 parts of sodium gluconate, 5-15 parts of white sugar, 0.2-0.25 part of sodium dodecyl benzene sulfonate, 0.3-0.5 part of xanthan gum, 0.5-1.0 part of hydroxyethyl methyl cellulose ether, 0.15-0.25 part of organic silicon defoamer and the balance of water.

The method has the greatest advantage that the sand rate of the mountain sand concrete is dynamically adjusted according to the fluctuation condition of the sand content of the mountain sand, so that the total mud content introduced by the mountain sand in single-side concrete tends to be an intermediate value and the fluctuation value of the total mud content is minimized, and the defects of the concrete working performance caused by the fluctuation of the sand content of the mountain sand in the prior art are overcome. The design method of the invention can timely and finely adjust the mixing ratio of the mountain sand concrete according to the actual mud content of the mountain sand, so that the adaptability of the obtained admixture and the mountain sand with mud content fluctuation is good, the advantages of improving the concrete wrapping property and water retention property by mud production can be exerted, the secondary environmental pollution caused by excessive washing of the mountain sand is avoided, and the mountain sand with mud content exceeding the standard is effectively utilized. In addition, the design method is instructive in application, uncontrollable brought by artificial experience in the construction process can be effectively avoided, and the design method has remarkable application value.

Detailed Description

The relevant indexes of the two types of mountain sand used in the following examples 1 to 4 are shown in Table 1; the cement is P.O42.5 ordinary silica cement produced by Dingxin cement; the fly ash is grade II ash produced by a Xibaipo power plant, the fineness is 8.2 percent, the loss on ignition is 3.1 percent, and the water demand ratio is 101.5 percent; the mineral powder is Shandong Luxin S95 mineral powder, and the fluidity ratio is 99%; the coarse aggregate is 5-31.5 mm continuous graded broken stone, the crushing value is 7.8%, the mud content is 0%, the mud block content is 0%, and the needle-shaped particle content is 0%; the polycarboxylate superplasticizer is designed according to the average mud content of the sand and the corresponding sand rate; the mixing water is tap water.

TABLE 11 # 2# mountain sand correlation performance index

Numbering	Modulus of fineness	Stone powder content%	Content of mud block%	The fluctuation range of mud content%
					1#	2.8	0	0	1.0～6.0
2#	2.8	0	0	1.0～4.0

Example 1

Taking the mountain sand concrete with the strength grade of C20, the initial slump of 200mm and the 2h slump retention value of 180mm as an example, the concrete mixing proportion design is carried out according to the following steps:

(1) according to a GB/T14684 test method of building sand, the fluctuation range of the mud content of 1# mountain sand is determined to be 1.0-6.0 percent through testing;

(2) determining the sand rate corresponding to the mountain sand concrete by taking the average mud content of the mountain sand as 3.5 percent as a reference: firstly, determining the sand rate beta corresponding to the mud content of 0 percent according to the fineness modulus of the hill sand specified in JGJ 55 design rules of common concrete_s44%, calculating and determining the sand rate beta corresponding to the average mud content in a mode that the sand rate is reduced by 1% when the mud content is increased by 1%^/ _s＝40.5％；

The average mud content of the mountain sand is 3.5 percent and the corresponding sand rate beta^/ _s40.5% as reference, designThe additive comprises the following components (the water reducing rate is 20% when the adding amount is 1.0%) in parts by mass: 220 parts of polycarboxylic acid water-reducing master batch with the solid content of 40%, 150 parts of polycarboxylic acid slump-retaining master batch with the solid content of 40%, 5 parts of sodium gluconate, 15 parts of white sugar, 0.1 part of sodium dodecyl benzene sulfonate, 0.6 part of xanthan gum, 1.5 parts of hydroxyethyl methyl cellulose ether, 0.1 part of organic silicon defoamer and the balance of water, and determining the design parameters of the average mud content reference hill sand concrete mixing ratio by mass method according to the regulations of common concrete mixing ratio design regulation JGJ 55 (wherein the mixing amount of fly ash is 20% and the mixing amount of mineral powder is 10%): cement dosage m_c0219kg, the amount of the fly ash m_f063kg of mineral powder dosage m_k031kg, sand dosage m_s0757kg, stone dosage m_g01112kg, water consumption m_w0188kg of additive dosage (namely the total dosage of the components of the compound additive)_a01.0%;

(3) then, taking the average mud content of the mountain sand as a reference, when the actual mud content of the mountain sand is measured to be 6.0 percent, calculating and determining that the sand rate corresponding to the mud content of 6.0 percent is 38 percent (namely 40.5 to 2.5 percent) according to the amplitude mode that the sand rate is reduced by 1 percent when the mud content is increased by 1 percent, and then calculating and determining the design parameters of the mixing proportion of the mountain sand concrete: cement dosage m^/ _c0219kg, the amount of the fly ash m^/ _f063kg of mineral powder dosage m^/ _k031kg, sand dosage m^/ _s0710kg, stone dosage m^/ _g01159kg, water consumption m^/ _w0188kg of additive dosage m^/ _a01.0%;

when the actual mud content of the mountain sand is measured to be 1.0%, the sand rate corresponding to the mud content of 1.0% is determined to be 43% (namely 40.5% + 2.5%) by calculation according to the mode that the sand rate is improved by 1% when the mud content is reduced by 1%, and then the design parameters of the mix proportion of the mountain sand concrete are determined by calculation: cement dosage m^/ _c0219kg, the amount of the fly ash m^/ _f063kg of mineral powder dosage m^/ _k031kg, sand dosage m^/ _s0804kg, stone dosage m^/ _g01065kg, water consumption m^/ _w0188kg of additive dosage m^/ _a0Is 1.0%.

The mix ratio and the workability of the mountain sand concrete of example 1 are shown in tables 2 and 3.

Example 2

Taking the mountain sand concrete with the strength grade of C35, the initial slump of 200mm and the 2h slump retention value of 180mm as an example, the concrete mixing proportion design is carried out according to the following steps:

(2) determining the sand rate corresponding to the mountain sand concrete by taking the average mud content of the mountain sand as 3.5 percent as a reference: firstly, determining the sand rate beta corresponding to the mud content of 0 percent according to the fineness modulus of the hill sand specified in JGJ 55 design rules of common concrete_sThe sand rate beta corresponding to the average mud content is calculated and determined in such a manner that the sand rate decreases by 1% every time the mud content increases by 1%^/ _s＝37.5％；

The average mud content of the mountain sand is 3.5 percent and the corresponding sand rate beta^/ _s37.5 percent as a standard, and the components of the admixture (the water reducing rate is 25 percent when the admixture is added in 1.0 percent) are designed to comprise the following components in parts by mass: 280 parts of polycarboxylic acid water-reducing master batch with the solid content of 40%, 180 parts of polycarboxylic acid slump-retaining master batch with the solid content of 40%, 15 parts of sodium gluconate, 5 parts of white sugar, 0.2 part of sodium dodecyl benzene sulfonate, 0.5 part of xanthan gum, 1.0 part of hydroxyethyl methyl cellulose ether, 0.2 part of organic silicon defoamer and the balance of water, and determining the design parameters of the average mud content reference hill sand concrete mixing ratio by mass method according to the regulations of common concrete mixing ratio design regulation JGJ 55 (wherein the mixing amount of fly ash is 20% and the mixing amount of mineral powder is 10%): cement dosage m_c0308kg, the using amount of the fly ash m_f088kg of mineral powder dosage m_k044kg, sand dosage m_s0669kg, stone dosage m_g01115kg, water consumption m_w0176kg, additive dosage m_a01.0%;

(3) then, based on the average mud content of 3.5% of the sand, when the actual mud content of the sand is measured to be 6.0%, the mud content is determined to be 6.0% according to the calculation in a mode that the sand rate is reduced by 1% when the mud content is increased by 1%The corresponding sand rate is 35%, and then the design parameters of the mix proportion of the mountain sand concrete are calculated and determined: cement dosage m^/ _c0308kg, the using amount of the fly ash m^/ _f088kg of mineral powder dosage m^/ _k044kg, sand dosage m^/ _s0624kg, stone dosage m^/ _g01160kg, water consumption m^/ _w0176kg, additive dosage m^/ _a01.0%;

when the actual mud content of the mountain sand is measured to be 1.0%, calculating and determining the sand rate corresponding to the mud content of 1.0% to be 40% according to the mode that the sand rate is improved by 1% when the mud content is reduced by 1%, and then calculating and determining the design parameters of the mix proportion of the mountain sand concrete: cement dosage m^/ _c0308kg, the using amount of the fly ash m^/ _f088kg of mineral powder dosage m^/ _k044kg, sand dosage m^/ _s0714kg, stone dosage m^/ _g01070kg, water consumption m^/ _w0176kg, additive dosage m^/ _a0Is 1.0%.

The mix ratio and the workability of the mountain sand concrete of example 2 are shown in tables 2 and 3.

Example 3

Taking the mountain sand concrete with the strength grade of C40, the initial slump of 200mm and the 2h slump retention value of 180mm as an example, the concrete mixing proportion design is carried out according to the following steps:

(1) according to a GB/T14684 test method of building sand, the fluctuation range of the mud content of the No. 2 mountain sand is determined to be 1.0-4.0 percent through testing;

(2) determining the sand rate corresponding to the mountain sand concrete by taking the average mud content of the mountain sand as the reference, wherein the average mud content of the mountain sand is 2.5 percent: firstly, determining the sand rate beta corresponding to the mud content of 0 percent according to the fineness modulus of the hill sand specified in JGJ 55 design rules of common concrete_sAnd calculating and determining the sand rate beta corresponding to the average mud content by the way that the mud content is increased by 1% and the sand rate is reduced by 1%^/ _s＝35.5％；

The average mud content of the mountain sand is 2.5 percent and the corresponding sand rate beta^/ _sDesigning additive components (doping) by taking 35.5 percent as a referenceAmount 1.0% water reduction rate 27.5%) comprises, in parts by mass per thousand: 320 parts of polycarboxylic acid water-reducing master batch with the solid content of 40%, 200 parts of polycarboxylic acid slump-retaining master batch with the solid content of 40%, 5 parts of sodium gluconate, 15 parts of white sugar, 0.2 part of sodium dodecyl benzene sulfonate, 0.5 part of xanthan gum, 1.0 part of hydroxyethyl methyl cellulose ether, 0.15 part of organic silicon defoamer and the balance of water, and determining the design parameters of the average mud content reference hill sand concrete mixing ratio by mass method according to the regulations of common concrete mixing ratio design regulation JGJ 55 (wherein the mixing amount of fly ash is 15% and the mixing amount of mineral powder is 10%): cement dosage m_c0335kg, the using amount of the fly ash m_f067kg, the amount of the mineral powder m_k045kg, sand dosage m_s0633kg, stone dosage m_g01150kg, water consumption m_w0170kg, additive dosage m_a01.0%;

(3) then, taking the average mud content of the mountain sand as a reference, when the actual mud content of the mountain sand is measured to be 4.0 percent, calculating and determining that the sand rate corresponding to the mud content of 4.0 percent is 34 percent according to the mode that the sand rate is reduced by 1 percent when the mud content is increased by 1 percent, and then calculating and determining the design parameters of the mixing ratio of the mountain sand concrete: cement dosage m^/ _c0335kg, the using amount of the fly ash m^/ _f067kg, the amount of the mineral powder m^/ _k045kg, sand dosage m^/ _s0606kg, stone dosage m^/ _g01177kg, water consumption m^/ _w0170kg, additive dosage m^/ _a01.0%;

when the actual mud content of the mountain sand is measured to be 1.0%, calculating and determining that the sand rate corresponding to the mud content of 1.0% is 37% according to the mode that the sand rate is improved by 1% when the mud content is reduced by 1%, and then calculating and determining the design parameters of the mix proportion of the mountain sand concrete: cement dosage m^/ _c0335kg, the using amount of the fly ash m^/ _f067kg, the amount of the mineral powder m^/ _k045kg, sand dosage m^/ _s0660kg of stone dosage m^/ _g01123kg, water consumption m^/ _w0170kg, additive dosage m^/ _a0Is 1.0%.

The mix ratio and the workability of the mountain sand concrete of example 3 are shown in tables 2 and 3.

Example 4

Taking the mountain sand concrete with the strength grade of C50, the initial slump of 200mm and the 2h slump retention value of 180mm as an example, the concrete mixing proportion design is carried out according to the following steps:

(2) determining the sand rate corresponding to the mountain sand concrete by taking the average mud content of the mountain sand as the reference, wherein the average mud content of the mountain sand is 2.5 percent: firstly, determining the sand rate beta corresponding to the mud content of 0 percent according to the fineness modulus of the hill sand specified in JGJ 55 design rules of common concrete_sThe sand rate beta corresponding to the average mud content is calculated and determined in a mode that the mud content is increased by 1% and the sand rate is reduced by 1%^/ _s＝34.5％；

The average mud content of the mountain sand is 2.5 percent and the corresponding sand rate beta^/ _s34.5 percent as a standard, and the components of the admixture (the water reducing rate is 32 percent when the admixture is added in 1.0 percent) are designed to comprise the following components in parts by mass: 400 parts of polycarboxylic acid water-reducing master batch with the solid content of 40%, 250 parts of polycarboxylic acid slump-retaining master batch with the solid content of 40%, 15 parts of sodium gluconate, 5 parts of white sugar, 0.25 part of sodium dodecyl benzene sulfonate, 0.3 part of xanthan gum, 0.5 part of hydroxyethyl methyl cellulose ether, 0.25 part of organic silicon defoamer and the balance of water, and determining the design parameters of the average mud content reference hill sand concrete mixing ratio by mass method according to the regulations of common concrete mixing ratio design regulation JGJ 55 (wherein the mixing amount of fly ash is 10% and the mixing amount of mineral powder is 10%): cement dosage m_c0394kg, the amount of the fly ash m_f049kg, the amount of the mineral powder m_k049kg, sand dosage m_s0607kg of stone, m_g01151kg, water consumption m_w0160kg, the dosage of the admixture m_a01.0%;

(3) then, taking the average mud content of the mountain sand as a reference, when the actual mud content of the mountain sand is measured to be 4.0 percent, calculating and determining that the sand rate corresponding to the mud content of 4.0 percent is 33 percent according to the mode that the sand rate is reduced by 1 percent when the mud content is increased by 1 percent, and then calculating and determining the design parameters of the mixing ratio of the mountain sand concrete: cementDosage m^/ _c0394kg, the amount of the fly ash m^/ _f049kg, the amount of the mineral powder m^/ _k049kg, sand dosage m^/ _s0580kg of stone in m^/ _g01178kg, water consumption m^/ _w0160kg, the dosage of the admixture m^/ _a01.0%;

when the actual mud content of the mountain sand is measured to be 1.0%, calculating and determining that the sand rate corresponding to the mud content of 1.0% is 36% according to the mode that the sand rate is improved by 1% when the mud content is reduced by 1%, and then calculating and determining the design parameters of the mix proportion of the mountain sand concrete: cement dosage m^/ _c0394kg, the amount of the fly ash m^/ _f049kg, the amount of the mineral powder m^/ _k049kg, sand dosage m^/ _s0633kg, stone dosage m^/ _g01125kg, the amount of water used, m^/ _w0160kg, the dosage of the admixture m^/ _a0Is 1.0%.

The mix ratio and the workability of the mountain sand concrete of example 4 are shown in tables 2 and 3.

TABLE 2 mountain sand concrete mix proportion

TABLE 3 working Properties of mountain sand concrete

Examples 1 to 4 show that: aiming at the mud content fluctuating mountain sand with mud content meeting the standard and trace exceeding the standard, the mixing proportion design method can effectively solve the adaptability problem of the admixture and the mud content fluctuating mountain sand, and has certain technical and economic rationality and remarkable social and economic benefits.

Comparative example 5

(2) the sand content of 1.0-6.0% is determined according to the fineness modulus of the hill sand and the corresponding sand rate of beta according to the specification of JGJ 55 of the design rule of the mix proportion of common concrete_s44 percent, and the admixture component (the water reducing rate is 21 percent when the admixture is added in an amount of 1.0 percent) comprises the following components in parts by mass: 240 parts of polycarboxylic acid water-reducing master batch with the solid content of 40%, 160 parts of polycarboxylic acid slump-retaining master batch with the solid content of 40%, 10 parts of sodium gluconate, 10 parts of white sugar, 0.2 part of sodium dodecyl benzene sulfonate, 0.6 part of xanthan gum, 1.2 parts of hydroxyethyl methyl cellulose ether, 0.2 part of organic silicon defoamer and the balance of water, and the formulation design parameters of the mountain sand concrete with the mud content of 1.0-6.0% are determined by mass method according to the specification of JGJ 55 (the blending amount of fly ash is 20% and the blending amount of mineral powder is 10%) of the design rules of the common concrete blending ratio: cement dosage m_c0221kg of fly ash and m of fly ash_f063kg of mineral powder dosage m_k031kg, sand dosage m_s0822kg, stone dosage m_g01047kg, water consumption m_w0186kg of additive dosage m_a0Is 1.0%.

The mix ratio and the working properties of the mountain sand concrete of comparative example 5 are shown in tables 4 and 5.

TABLE 4 mountain sand concrete mix proportion

TABLE 5 working Properties of mountain Sand concrete

As can be seen from comparative example 5: aiming at the mountain sand with fluctuating mud content, the sand rate is not correspondingly adjusted according to the change condition of the actual mud content of the mountain sand, and the admixture components are not designed according to the average value of the mud content of the mountain sand and the corresponding sand rate, so that serious inadaptability exists between the admixture and the mountain sand, and the initial slump and the slump loss of the concrete are extremely difficult to control.

Although the invention has been described in detail hereinabove with respect to a general description and specific embodiments thereof, it will be apparent to those skilled in the art that modifications or improvements may be made thereto based on the invention. Accordingly, such modifications and improvements are intended to be within the scope of the invention as claimed.

Claims

1. A design method for mixing proportion of mountain sand concrete with fluctuating mud content is characterized by comprising the following steps:

(2) calculating the average mud content of the mountain sand by using the mud content fluctuation range, and determining the sand rate corresponding to the mountain sand concrete by using the average mud content as a reference: firstly, determining the sand rate beta corresponding to the mud content of 0 percent according to the fineness modulus of the hill sand_sThen, the sand rate beta corresponding to the average mud content is calculated and determined in a mode that every time the mud content is increased by 1 percent, the sand rate is reduced by 1 percent^/ _s；

(3) Testing to determine the mud content of the mountain sand on site, calculating the difference n% from the average mud content, and calculating the sand rate beta corresponding to the mountain sand concrete according to the mode that the sand rate is reduced by 1% when the mud content is increased by 1% on the basis of the average mud content of the mountain sand^/ _s-n%, calculating the design parameters of the mix proportion of the sand concrete according to the following rules: cement dosage m^/ _c0＝m_c0The amount of the fly ash m^/ _f0＝m_f0The amount of the mineral powder m^/ _k0＝m_k0Sand dosage m^/ _s0＝(β^/ _s-n％)×(m_s0+m_g0) Amount of stone m^/ _g0＝(m_s0+m_g0-m^/ _s0) Water consumption m^/ _w0＝m_w0The dosage m of the admixture^/ _a0＝m_a0；

2. The mountain sand concrete mix proportion design method with fluctuating mud content of claim 1, wherein the test of the mud content of the mountain sand adopts a test method of 'building sand' GB/T14684.

3. The method for designing the mix proportion of the mountain sand concrete with fluctuating mud content according to claim 1, wherein the method for determining the sand ratio corresponding to the mud content of 0% from the modulus of fineness of the mountain sand in the step (2) and the method for determining the design parameters of the mix proportion of the mountain sand concrete under the reference conditions of average mud content are both specified by the design rule of common concrete mix proportion JGJ 55.

4. The mix proportion design method of the mountain sand concrete with fluctuating mud content as claimed in claim 1, wherein the step (2) comprises the following components by mass per thousand parts of the additive: