CN204989179U - Early volume self -constriction testing arrangement of mortar - Google Patents

Abstract

The utility model discloses a mortar early volume self-shrinkage test device, which comprises an open bottle, a sample sealing bag is placed in the open bottle, a mortar sample is arranged in the sample sealing bag, and the sample sealing bag can be used together with the mortar sample. The volume changes and shrinks freely; the open bottle is filled with liquid, the bottle mouth of the open bottle is sealed by a rubber stopper, the bottom of the open bottle is provided with a water outlet, and the water outlet is connected with the graduated straw on the upper opening through a plastic hose. The suction pipe is fixedly connected with the iron frame platform. The utility model puts the mortar to be tested in a balloon or a rubber bag, avoiding the direct contact between the mortar to be tested and the open bottle to damage the open bottle, and only needs to replace the balloon or rubber bag when testing different samples, realizing the open The repeated use of the mouth bottle reduces the waste of resources; the principle of the change of the discharge volume of the sealed sample is used for testing, which can more comprehensively reflect the shrinkage of the mortar, which is more accurate than the length and height method, and the result is more reliable.

Description

A testing device for early volume self-shrinkage of mortar

technical field

The utility model relates to the technical field of mortar volume testing, in particular to an early volume self-shrinkage testing device for mortar.

Background technique

With the continuous development of concrete production technology and construction mortar technology and the continuous improvement of construction engineering quality requirements, the durability of concrete and mortar has been paid attention to. The problem of cracks, especially the cracks caused by the early shrinkage of mortar has become the focus of research and discussion in the field of building materials in my country and the world in recent years. There is a lot of water in ordinary concrete with high water-binder ratio and the pore size is large, and the relative value of autogenous shrinkage is low; The early self-shrinkage of concrete is also more and more significant, and the proportion of autogenous shrinkage in the whole shrinkage is also increasing. The main component that produces self-shrinkage in concrete is mortar, and the self-shrinkage of mortar runs through the entire process of cement hardness development.

The self-shrinkage of mortar is not caused by heat or water evaporation, and it occurs simultaneously with drying shrinkage, mainly through testing the reduction in apparent volume or length under constant temperature and airtight conditions. At present, the self-shrinkage test of mortar basically adopts the length test method, which cannot fully reflect the overall shrinkage of the mortar, and the measurement accuracy is low. Chinese patent (CN102226803A) discloses a detection method for early self-shrinkage of cement mortar, which reflects the early self-shrinkage of cement mortar by directly measuring the volume of cement mortar over time. The test method is simple and practical, but in this method The Erlenmeyer flask is a disposable consumable, which wastes resources; secondly, the dropper used in this method has a minimum range of 1mL, which makes it difficult to measure the self-shrinkage of mortar with high water-binder ratio; Tightness, thereby reducing the accuracy of measurement, this method needs to be further improved. Therefore, it is necessary to improve the prior art.

Contents of the invention

The technical problem to be solved by the utility model is to provide an early volume self-shrinkage testing device for mortar that is accurate, convenient, and reusable in view of the deficiencies in the prior art.

The technical solution adopted by the utility model is: a mortar early volume self-shrinkage testing device, including an open bottle, a sample sealing bag is placed in the open bottle, a mortar sample is housed in the sample sealing bag, and a sample sealing bag is placed in the open bottle. It can freely shrink with the change of the volume of the mortar sample; the mouth of the open bottle is sealed by a rubber stopper, and the bottom of the open bottle is provided with a water outlet, and the water outlet is connected with the graduated suction pipe at the upper end through a plastic hose. The suction pipe is fixedly connected with the iron frame platform.

According to the above scheme, the iron stand is equipped with a test tube clamp, and the test tube clamp fixes the graduated suction pipe in the vertical direction.

According to the scheme, the zero scale on the graduated straw is located above the mouth of the open bottle.

According to the above scheme, the sample sealing package is a balloon or a rubber ball, and the balloon or the rubber ball is tightly sealed by a string, and the string does not absorb water.

According to the above scheme, the water outlet of the open bottle is threadedly connected with the plastic hose.

According to the above scheme, the liquid is non-corrosive, non-volatile, and does not react with the sample sealing bag and the rubber stopper.

According to the above scheme, the minimum scale of the graduated straw is ≤0.001mL.

In the utility model, the open bottle is a cylindrical transparent glass bottle with a height ≥ 150 mm and a bottle mouth diameter ≥ 90 mm. The open bottle is provided with a water outlet at a distance of 1 to 10 mm from the bottom of the bottle; the mortar sample is sealed and installed in the test Put the sample in an open bottle after sealing the package, and the open bottle is filled with liquid; the measuring range of the graduated straw is ≥0.1mL (the measuring range can be selected according to the specific test sample), and the measurement accuracy of the graduated straw is ≤0.001mL; the inner diameter of the graduated straw is small , can reduce the volatilization of liquid.

Compared with the prior art, the utility model has the beneficial effects that: the open bottle and the graduated straw are connected through the water outlet at the bottom of the open bottle, which improves the overall air tightness and reduces the test error; the mortar to be tested is installed in the In the balloon or rubber bag, it avoids the direct contact between the mortar to be tested and the open bottle to damage the open bottle, and only needs to replace the balloon or rubber bag when testing different samples, realizing the repeated use of the open bottle and reducing resources Waste; there are many options for the measuring range and the minimum scale of the graduated straw, which can realize the early volume self-shrinkage test of mortars with different water-binder ratios, and the test accuracy is high; the test is carried out using the principle of the volume change of the sealed sample drainage, which can reflect more comprehensively The shrinkage of the mortar is more accurate than the length and height method, and the result is more reliable; the device is simple, easy to operate, and the test efficiency is improved.

Description of drawings

Fig. 1 is a structural schematic diagram of a specific embodiment of the present invention.

Figure 2 is a schematic diagram of the connection between the open bottle and the graduated straw in this embodiment.

Fig. 3 is a left side view of Fig. 2 .

FIG. 4 is a top view of FIG. 2 .

Among them: 1. Rubber stopper; 2. Open bottle; 3. Water outlet; 4. Plastic hose; 5. Iron stand; 6. Graduated straw; 7. Balloon; 8. String.

detailed description

In order to better understand the utility model, the utility model will be further described below in conjunction with the accompanying drawings and specific embodiments.

A kind of early volume self-shrinkage testing device for mortar as shown in Figures 1 to 4, includes an open bottle 2, a sample sealing bag is placed in the open bottle 2, a mortar sample is housed in the sample sealing bag, and the sample sealing bag It can freely shrink with the change of the mortar sample volume; the open bottle 2 is filled with liquid, and the bottle mouth of the open bottle 2 is sealed by the rubber stopper 1, and the liquid in the open bottle 2 is non-corrosive, non-volatile, and incompatible with the test The liquid that reacts between the sample sealing bag and the rubber stopper 1; the bottom of the open bottle 2 is provided with a water outlet 3, and the water outlet 3 communicates with the graduated straw 6 opened at the upper end through a plastic hose 4, and the graduated straw 6 is fixedly connected with the iron stand 5 ; The zero scale line on the scale suction pipe 6 is positioned at the top of the open bottle 2 bottlenecks.

In the present embodiment, the iron frame platform 5 is equipped with a test tube clamp, and the test tube clamp fixes the graduated straw 6 in the vertical direction; the water outlet 3 of the open bottle 2 is threaded with the plastic hose 4; the open bottle 2 and the graduated straw 6 are all It is transparent, and the minimum scale of the graduated straw 6 is ≤0.001mL.

Preferably, the sample sealing package is a balloon 7 or a rubber ball. In this embodiment, the balloon 7 is used and sealed by a string 8 to prevent the mortar sample from flowing out or other liquids from flowing in.

The open bottle 2 in the present embodiment is a cylindrical transparent glass bottle with a height of 200 mm and a bottleneck diameter of 90 mm; the open bottle 2 is provided with a water outlet 3 with a diameter of about 10 mm on the bottle body 5 mm from the bottom, and the water outlet 3 The outer surface of the outer surface is provided with threads, and the plastic hose 4 realizes thread-tight connection.

Place the test device in an environment with a temperature of 20°C±2°C and a relative humidity of 60%±5%. After adding a certain amount of distilled water (not full), plug the mouth of the bottle tightly with rubber stopper 1 and seal it. Since there is gas remaining in the open bottle 2, when the rubber stopper 1 is tightly closed, a certain pressure will be generated on the liquid in the bottle, causing the open bottle to leak. There is a certain liquid level difference between the mouth bottle 2 and the external graduated straw 6; after the rubber stopper 1 is tightly closed, place a 1-2kg object on the rubber stopper 1 to keep the rubber stopper 1 in a tight state for a long time, Otherwise, the rubber stopper 1 will deform slowly, and the pressure in the bottle will decrease; record the initial scale value of the graduated straw 6 and the scale value after 5 hours, if the two scale values remain unchanged, then the airtightness of the device is good; If the airtightness is poor, use Vaseline to smear the interface and other places to ensure the airtightness of the test device.

After the air tightness test is completed, the mortar volume self-shrinkage test is started. The specific test process includes the following steps:

1. Soak the inside of the open bottle 2 and the graduated straw 6 with distilled water;

2. Mix the mortar samples to be tested according to the requirements, and record the time of adding water;

3. Test the density ρ of the mortar sample according to the standard;

4. Weigh the mass m ₀ of the balloon 7, put the mixed mortar sample into the balloon 7, and after the air bubbles are fully removed, fasten it with a non-absorbent string 8; weigh the total mass of the balloon 7 and the mortar sample m ₁ , accurate to 0.01g;

5. Put the balloon 7 containing the mortar sample into the open bottle 2, and fill the bottle with distilled water. After fully removing the air bubbles, use the rubber stopper 1 to seal the bottle mouth tightly, and place a 1~ on the rubber stopper 1. 2kg items;

6. Use a dropper to drip distilled water into the graduated straw 6, so that the liquid level of the graduated straw 6 is at the zero scale line, and record the time and the initial scale v ₀ (accurate to 0.001mL); after adding the distilled water Start at 0.5 hours, read and record the reading v _t of the graduated straw 6 every 3 hours, and continue to observe and record for 7 days;

7. The volume self-shrinkage rate ε of the mortar sample from the initial time t ₀ to a certain time t is calculated according to the following formula, and the calculation result is accurate to 0.1%:

$\mathrm{<span\; class="notranslate">\; \&epsiv;</span>}<span\; class="notranslate">\; =</span>\frac{<span\; class="notranslate">\; (</span>{\mathrm{<span\; class="notranslate">\; v</span>}}_{\mathrm{<span\; class="notranslate">\; t</span>}}<span\; class="notranslate">\; -</span>{\mathrm{<span\; class="notranslate">\; v</span>}}_{\mathrm{<span\; class="notranslate">\; 0</span>}}<span\; class="notranslate">\; )</span><span\; class="notranslate">\; \&times;</span>\mathrm{<span\; class="notranslate">\; \&rho;</span>}}{{\mathrm{<span\; class="notranslate">\; m</span>}}_{\mathrm{<span\; class="notranslate">\; 1</span>}}<span\; class="notranslate">\; -</span>{\mathrm{<span\; class="notranslate">\; m</span>}}_{\mathrm{<span\; class="notranslate">\; 0</span>}}}<span\; class="notranslate">\; \&times;</span>\mathrm{<span\; class="notranslate">\; 100</span>}\mathrm{<span\; class="notranslate">\; \%</span>}$

The liquid in the open bottle 2 can also be other non-corrosive, non-volatile, and non-reactive liquids with the mortar sealing bag and the rubber stopper 1. If necessary, a color developer that does not affect the test results can be added to it. The liquid should not contain Air bubbles or remove air bubbles in advance.

The above is only a specific embodiment of the present utility model, but the scope of protection of the present utility model is not limited thereto. Any person skilled in the art can easily think of changes or replacements within the technical scope disclosed in the utility model. All should be covered within the protection scope of the present utility model. Therefore, the protection scope of the present utility model should be determined by the protection scope defined in the claims.

Claims (7)

1. a mortar early stage volume self-constriction proving installation, is characterized in that, comprises uncovered bottle, is placed with sample sealed packet in uncovered bottle, sample sealed packet built with mortar specimen, sample sealed packet can with the change of mortar specimen volume free shrink; Uncovered bottle liquid is full of, and the bottleneck of uncovered bottle is by rubber stopper seal, and the bottom of uncovered bottle offers water delivering orifice, and water delivering orifice is communicated with the calibrated pipet of upper end open by plastic flexible pipe, and calibrated pipet is fixedly connected with iron stand.

2. a kind of mortar as claimed in claim 1 early stage volume self-constriction proving installation, it is characterized in that, described iron stand is provided with test tube clamp, and calibrated pipet is fixed in the vertical direction by test tube clamp.

3. a kind of mortar as claimed in claim 1 early stage volume self-constriction proving installation, is characterized in that, the zero graduation on described calibrated pipet is positioned at the top of uncovered bottle bottleneck.

4. a kind of mortar as claimed in claim 1 early stage volume self-constriction proving installation, is characterized in that, described sample sealed packet is balloon or rubber ball, and balloon or rubber ball fasten sealing by cord, and described cord does not absorb water.

5. a kind of mortar as claimed in claim 1 early stage volume self-constriction proving installation, is characterized in that, the water delivering orifice of described uncovered bottle is threaded with plastic flexible pipe.

6. a kind of mortar as claimed in claim 1 early stage volume self-constriction proving installation, is characterized in that, described liquid is liquid that is corrosion-free, not volatile, that do not react with sample sealed packet and rubber plug.

7. a kind of mortar as claimed in claim 1 early stage volume self-constriction proving installation, is characterized in that, the minimum scale≤0.001mL of described calibrated pipet.