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The Efficiency of Waterproofing Agents in Concrete: Assessment of Compressive Strength and Permeability

Salman Ayyoob, Mohd Zaki, Mohammad Saaim Khan, Sahil Ali Khan, Mohammad Arif Kamal*

Architecture Section, Aligarh Muslim University, Aligarh, India

Abstract: In this paper, issues limiting the durability of structures with reference to permeability to water, reinforcement corrosion, the occurrence of cracks, and degradation of cracks have been studied and addressed with possible solutions. The major issues identified are because of the water ingress, in particular capillary absorption and permeability, to address these problems and to identify possible solutions to the problem an experimental procedure is proposed to assess the different concentrations of concrete. The different concentrations of concrete include styrene butadiene rubber (SBR), acrylic polymer (AC), and Natural rubber latex (NR) and their combinations with each other. The experimental procedure includes the formation of 150 X 150 X 150 mm cubes of different concentrations of concrete which are normal or without chemical (WC), SBR, SBR+AC, AC, SBR+NR, and AC+NR. With these cubes of different concentrations, four experimental tests were conducted in the lab to assess the compressive strength and the reduction in permeability in comparison with the normal concrete, these tests are compressive strength, ultrasonic pulse velocity (UPV), rebound hammer test, and permeability test. In the test, the most effective solution is the addition of SBR, and by adding SBR (10% by the weight of cement) compressive strength was reduced by 5% and 60% reduction in permeability in comparison with the normal concrete.

Keywords: water ingress, capillary absorption, permeability, compressive strength, styrene-butadiene rubber

Received September 05, 2022; Revised October 07, 2022; Accepted October 16, 2022

Citation: Salman Ayyoob, Mohd Zaki, Mohammad Saaim Khan, Sahil Ali Khan, Mohammad Arif Kamal, The Efficiency of Waterproofing Agents in Concrete: Assessment of Compressive Strength and Permeability. American Journal of Civil Engineering and Architecture, 10 (3). 137-146. January 2022. doi:10.12691/ajcea-10-3-4

1. Introduction

The majority of building materials, such as concrete, mortar, burnt clay bricks, and others, which have intermolecular spaces or pores in their structure, expand when wet from the atmosphere and contract when they are dried. Building materials either absorb water from the air or have water flow over them [1]. The porosity of the structure when structures are exposed to the atmosphere is another factor for water penetration. Water progressively absorbed by the components led to leaks through the roof terrace and walls that were exposed to the atmosphere [2]. The deterioration of buildings is a frequent problem. Concrete is a porous substance, therefore if it is not sufficiently waterproofed, it will eventually suffer significant damage. Waterproofing can expand the life of concrete to between 25 and 50 years, as opposed to poorly waterproofed concrete which will likely only last several years before it needs repair.

The main factor contributing to the deterioration of concrete components is corrosion of the reinforcing. The impact of corrosion on the concrete member is the same regardless of the reason, whether it is due to carbonization, chloride ions, oxygen penetration, insufficient cover, or any other diverse factors [3]. A reinforced concrete pier column's residual strength may be impacted by corrosion in many ways, including section loss of reinforcement, corroded reinforcement that is less strong, reduction in concrete cross-section owing to corrosion-induced cracking and spalling, and loss of bond strength. The ductility of RC sections can be dramatically decreased by corrosion. In seismic design and evaluation, this is crucial. Corroded sections have less ductility, which limits their ability to deform plastically. This will affect the seismic response of the elements.

Water infiltration causes many issues with brick masonry walls, including efflorescence, mortar joint deterioration, interior moisture damage, and spalling. When a brick wall masonry building has one or more problems with water infiltration, it is necessary to address both the damaged area of the wall and the source of the water ingress [4]. The modern practicing engineer is very concerned about concrete durability. Due to the varied climate, concrete structures are frequently exposed to harsh conditions that compromise their endurance. Permeability to water, the emergence of fractures, corrosion of the reinforcement, and concrete degradation is the key factors limiting the durability of structures. Such harm is typically caused by water. Thus, acting as a transport medium or as an essential component for nearly all the deterioration mechanisms of concrete.

2. Strength and Permeability

In this research, the causes that create a path for the reduction of the strength of the concrete and also increase its vulnerability towards permeability are discussed and while analyzing the problems this section will also assess possible solutions to assess these problems,

2.1. Mechanism of Water Ingress

Moisture migration into concrete is the leading cause of concrete degradation worldwide. There are two primary water transport mechanisms in concrete. Considering water’s powerful forces and then designing concrete structures to adequately resist the known effects of these two common water transport mechanisms is paramount to achieving durable structures [5]. Designers, contractors, and owners need to thoroughly understand the differences in the mechanisms to ensure the structures they are building provide adequate problem-free service life. Figure 1 - Figure 3 shows some of the major problems associated with water ingress and with the magnitude of the challenges the mechanism is categorized into two categories capillary absorption and permeability.

Figure 1. Corrosion of reinforcement

Figure 2. Blistering of paint

Figure 3. Cracks in concrete

2.1.1. Capillary Absorption

Capillary absorption is the movement of water through the small pores in concrete in the absence of an externally applied hydraulic head and is the result of surface interactions between the water and the pore wall. Capillary absorption is the primary transport mechanism for water in concrete structures. Capillary absorption is so powerful and rapid that it requires no pressure to function and creates far more damage potential than any of the other transport mechanisms [6]. Capillary absorption represents the main mechanism for water and water vapour transport in concrete. The capillary absorption of concrete increases with the increasing content of rubber particles due to its poor bonding with hydrated cement paste [7]. The size of the replaced aggregate is important to the increase in water absorption by capillarity since all the coarse rubber particles have higher absorption rates than the fine rubbers. When a rubber surface is considered on capillary water absorption, RC with mechanically ground fine rubber has lower water absorption by capillarity than RC made with fine cryogenic rubber particles. This is due to the better adherence between the cement paste and the mechanically ground rubber particles, due to their greater roughness [8].

2.1.2. Permeability

In general, cracks in concrete connect flow pathways and promote concrete permeability. As fractures develop, their permeability grows, allowing more water or damaging chemical ions to enter the concrete and speeding up deterioration [9]. Permeability defines how easily a fluid flows through a porous material. Materials with a high permeability allow easy flow, while materials with a low permeability resist flow [10]. The permeability is the movement of water due to a pressure gradient, such as when concrete is under hydrostatic pressure. Performance under hydrostatic pressure is a simple function of concrete density or cementitious content [11]. Concrete’s naturally dense matrix, (of even moderate quality mixes) provides an extremely difficult environment to push water through even under high pressure.

3. Research Methodology and Experimentation

To achieve the objectives, an experimental program was planned to investigate the mechanical property and permeability of latex-modified concrete( using latex, styrene-butadiene rubber, acrylic polymer and natural rubber). The experiments were conducted on a standard cube (150mm x 150mm x 150mm) of concrete mix M20 with 10% of latex by the weight of the cement. The properties of the material used in concrete are determined in the laboratory as per the relevant code of practice. Different materials used in the present study were cement, coarse aggregate, three types of latex named styrene-butadiene rubber, acrylic polymer, natural rubber latex, fine aggregate, and water. The materials in general conformed to the specifications laid down in the relevant Indian standard (IS) codes. The materials used were having the following characteristics.

3.1. Properties of Concrete Constituents

The determination of the properties of the constituents of concrete is necessary to ensure that they do not contain any deleterious element which may affect the behaviour of the composite or they may not conform to the specified requirement necessary to achieve the standard of performance. The subsection under this head gives the details of the test carried out and the specifications mention.

3.1.1. Cement

Cement is a binder, a substance used for construction that sets, hardens, and adheres to other materials to bind them together. Cement is seldom used on its own, but rather to bind sand and gravel (aggregate) together. Cement mixed with fine aggregate produces mortar for masonry, or sand and gravel produce concrete [12]. Cement is the most widely used material in existence and is only behind water as the planet's most-consumed resource. The cement used was Ultratech OPC 43 grade. The various cement test is performed as recommended by IS 8112: 2013 and various test values obtained are given in Table 1.

Table 1. Experimental properties of cement

3.1.2. Aggregates

IS: 383-1970 defines the aggregate for both fine and coarse aggregates from natural sources for concrete [13]. The aggregate is the matrix or principal structure consisting of relatively inert and coarse particles. The coarse aggregates are used primarily to provide bulk to the concrete. The most important function of fine aggregates is to assist in producing a workable and uniform concrete mix. The fine aggregates also assist the cement paste to hold the coarse aggregates particles in suspension [14]. This action promotes plasticity in the concrete mix and prevents segregation of the paste and coarse aggregates during its transportation. The aggregates provide about 75% of the body of concrete and hence their influence is extremely important. The properties of these particles greatly affect the performance of concrete.

3.1.3. Fine Aggregates

IS: 383-1970 defines the fine aggregate, as the one passing a 4.75mm IS sieve [13]. The fine aggregate is often termed a sand size aggregate. Locally available riverbed sand was used in the present study. The total weight of the sample = 1000g and the result of the sieve analysis of fine aggregate is listed in Table 2. With the sieve analysis of the fine aggregate, the fitness modulus is the sum of the percent of cumulative weight retained divided by 100, with this formula fitness modulus of the fine aggregates is 3.33 and the specific gravity is 2.78 according to the experiment.

Table 2. Sieve analysis of fine aggregates

3.1.4. Coarse Aggregate

IS: 383-1970 defines the fine aggregate, as the one passing a 4.75mm IS sieve [13]. The fine aggregate is often termed a sand-size aggregate. Locally available riverbed sand was used in the present study. The total weight of the sample = 1000g and the result of the sieve analysis of fine aggregate is listed in Table 3.

Table 3. Sieve Analysis of Coarse Aggregate (20mm)

Based on various tests as recommended according to IS 383: 2016, experimental values are listed in Table 4 [15].

Table 4. Properties of coarse Aggregates

3.1.5. Water

Water is the most important and the least expensive ingredient of concrete. One part of the water is used in the hydration of cement to form the binding matrix. The remaining water affords lubrication and workability to the concrete. The water-cement ratio depends on the grade of concrete, its workability, durability, types of aggregates etc. Potable water is ideal for concrete. Water used for mixing and curing shall be clean and free from injurious amounts of oils, acids, salts, organic materials etc.

3.2. Concrete Mix Design Proportion

To design a concrete mix for desired strength first we need to decide the constituent of the concrete mix such as cement, fine aggregate, coarse aggregate, admixtures, etc, and their optimum quantity that will result in the achievement of the requisite performance [16]. In general, the acceptance criteria of the concrete mix are its workability in the fresh state and compressive strength at the age of 28 days. As per the guidelines of IS 10262: (1982), the normal strength concrete mix M20 was designed [17]. The mix proportion for M20 is provided in Table 5 and mix design properties for the selected sample are also provided in Table 6 where WC is Without chemical concrete, SBR is styrene-butadiene rubber, AC is an acrylic polymer and NR is Natural rubber latex [18,19].

Table 5. Mix proportion for M20

Table 6. Mix design proportion

3.3. Testing and Analysis

Various types of tests such as compressive strength, ultrasonic pulse velocity, and permeability of specimen are conducted on the concrete cube of 150mm x 150mm x 150mm.

3.3.1. Compressive Strength

The compressive strength of concrete is one of the most important and useful properties of concrete. In most structural applications concrete is employed primarily to resist compressive stresses. Compressive strength is also used as a qualitative measure for other properties of hardened concrete. The compressive strength is generally determined by testing cubes. In the laboratory, the compressive strength is determined by a compression testing machine. The compressive strength of concrete depends on many factors such as water-cement ratio, cement strength, quality of concrete material, quality control during the production of concrete etc. Test for compressive strength is carried out either on a cube or cylinder. Various standard codes recommend a concrete cylinder or concrete cube as the standard specimen for the test. Compressive strength is the ability of a material or structure to carry the loads on its surface without any crack or deflection [20]. A material under compression tends to reduce its size, while in tension, size elongates [21].

For the cube test, two types of specimens either cubes of 150mm X 150mm X 150mm or depending upon the size of the aggregate are used. For most of the works cubical moulds of size, 150mm X 150mm X 150mm are commonly used. This concrete is poured into the mould and tempered properly so as not to have any voids. After 24 hours these moulds are removed and test specimens are put in water for curing. The top surface of these specimens should be made even and smooth. This is done by putting cement paste and spreading smoothly on the whole area of the specimen. These specimens are tested by a compression testing machine as shown in Figure 4, after 28 days of curing or 56 days of curing. Load should be applied gradually at the rate of 140 kg/cm² per minute till the Specimens fails. Load at the failure divided by the area of the specimen gives the compressive strength of concrete as shown in Figure 5.

Figure 4. Compressive strength machine

Figure 5. Tested Specimen

3.3.2. Ultrasonic Pulse Velocity Test (UPV)

An ultrasonic test on concrete is a non-destructive test to assess the homogeneity and integrity of the concrete. This test initially consists of measuring travel time, T of the ultrasonic pulse of 50 to 54 kHz, produced by a transducer held in contact with one surface of the concrete member under test and receiving the same by a similar transducer in contact with the surface at the other end. With path length L and time of travel T, the pulse velocity (V=L/T) is calculated higher the velocity modulus, density, and integrity of the concrete, the higher the pulse velocity. The ultrasonic pulse velocity depends upon the density and elastic properties of the material being tested [22]. The pulse velocity in the concrete may be influenced by, path length, lateral dimension, presence of reinforcement steel, and moisture content of the concrete. Pulse velocity will not be influenced by the shape of the specimen, provided its least lateral dimension is not less than the wavelength of the pulse vibrations. The velocity of pulses in steel bar is generally higher than they are in concrete. For this reason, pulse velocity measurement made in the vicinity of reinforcing steel may be high and not representative of the concrete. The influence of the reinforcement is generally small if the bars run in a direction at right angles to the path and the quality of steel is small concerning the path length. The moisture content of the concrete can have a small but significant influence on the pulse velocity [23]. In general, the velocity is increased with increased moisture content, the influence is more marked for lower-quality concrete. An example of the pulse of pulse velocity test is shown in Figure 6.

Figure 6. Ultrasonic pulse velocity test

3.3.3. Rebound Hammer Test

Rebound Hammer test is a Non-destructive testing method of concrete that provides a convenient and rapid indication of the compressive strength of the concrete. The rebound hammer also called as Schmidt hammer consists of a spring-controlled mass that slides on a plunger within a tubular housing as shown in Figure 7. When the plunger of the rebound hammer is pressed against the surface of the concrete, a spring-controlled mass with constant energy is made to hit the concrete surface to rebound back [24]. The extent of rebound, which is a measure of surface hardness, is measured on a graduated scale. This measured value is designated as the Rebound Number (rebound index). Concrete with low strength and low stiffness will absorb more energy to yield a lower rebound value [25]. The procedure for a rebound hammer test on a concrete structure starts with calibration of the rebound hammer. For this, the rebound hammer is tested against the test anvil made of steel having a Brinell hardness number of about 5000 N/mm2. After the rebound hammer is tested for accuracy on the test anvil, the rebound hammer is held at right angles to the surface of the concrete structure for taking the readings. The test thus can be conducted horizontally on a vertical surface and vertically upwards or downwards on horizontal surfaces as shown in Figure 7 If the rebound hammer is held at an intermediate angle, the rebound number will be different for the same concrete.

Figure 7. Rebound Hammer

3.3.4. Permeability of Concrete

The permeability of concrete is defined as the property that controls the rate of flow of fluids into a porous solid. It largely depends on the size of pores, connectivity of pores, and how tortuous the path is for the permeating fluid [26]. Concrete Permeability Apparatus is used for testing the water permeability of concrete. High-pressure permeability tests are conducted on various sizes of specimens by different cells [27]. As a result, pressure can be applied using any available pressure line at the compressor or site.

For the permeability check the specimen preparation will be to cast the 150mm cube specimen of concrete in the split mould as shown in Figure 8 after demolding thoroughly clean the specimen with a stiff wire brush to remove all laitance.

After sun drying the specimen for two days keep it with the top face on the side of the cell. Paste the top surface of the specimen with a piece of paper to prevent the sealing compound from blocking the face. Tightly fill the gap between the specimen and the cell to a depth of about 10mm using cotton soaked in a suitable molten ceiling compound. Fill the rest gap with a suitable molten ceiling compound as shown in Figure 9.

Figure 8. Casting of cubes

Figure 9. Sealing of specimen in permeability cell

The seal must be watertight. Put the cover plate on it and bolt it tight. After a satisfactory seal mounts the cell on the stand and connects the cell to the pressure chamber and pressure chamber to the compressor. Weigh the glass bottle and keep it in a position to collect the water percolating through the specimen. Fill the pressure chamber and cell assembly with water. Start the compressor. Apply desired test pressure to the water column at the top of the specimen pressure being regulated by turning the handle of the pressure regulator in the clockwise direction and then opening the release wall. Collect the quantity of water passing through the cube at the bottom. Record the operating pressure, the quantity of water collected, and the time of observation at intervals and continue the test till a uniform rate of flow is obtained.

Permeability tests were conducted in accordance with IS: 3085-1965 and using a water permeability testing apparatus as shown in Figure 10 and the coefficient of permeability was calculated using the following equation given in the code.

[picture] | (1)

Where K is the coefficient of permeability (cm/sec), Q is the Volume of water collected (ml), T is Time (sec), A is the Area of specimen face (cm²), H is the Pressure head (cm) of the specimen, L is the thickness of the specimen.

Figure 10. Water permeability testing apparatus.

4. Results and Discussion

To analyze the performance of different situations and concentrations experimental work is performed, the concrete cubes of dimensions 150mm x 150mm x 150mm were cast. Six different specimens are cast named, WC (Without chemical) does not contain any latex (M1), SBR has 10% content of SBR (Styrene butadiene rubber) by the weight of cement (M2), SBR + AC has 5% content of SBR + 5% of AC by the weight of cement (M3), AC has 10% content of acrylic polymer latex by the weight of cement. (M4), SBR + NR having 5% content of SBR + 5% of NR (Natural Rubber) by the weight of cement (M5), AC + NR having 5% content of AC+ 5% of NR by the weight of cement. (M6).

4.1. Compressive Strength

The cube specimens were tested in the compressive testing machine and were determined from the failure load measure. The average value of compressive strength of two specimens for each category at the age of 28 days and 56 days. A comparative study was made on the properties of concrete after mixing latex 10% by the weight of cement and a combination of latex 5% + 5% by the weight of cement. The compressive strength of specimens is listed in Table 7.

Table 7. Compressive strength of the specimen

The compressive strength of concrete mixtures made with and without latex was determined at 28, and 56 days of curing as shown in Figure 11. There was a decrease in the compressive strength of the inclusion of latex in concrete.

Figure 11. Variation of compressive strength

Table 7 demonstrates the compressive strength of specimens for 28 days. On adding waterproofing agent styrene butadiene rubber for making M20 grade concrete the compressive strength of the specimen SBR is found to be less as compared to WC and nearly 8% compressive strength is decreased in the case of SBR. On adding AC+SBR the compressive strength is reduced by about 18%. The compressive strength of specimen AC is reduced by about 21% as compared to normal concrete. For SBR + NR, the compressive strength is reduced by about 42%. For AC + NR, the compressive strength is reduced by about 48% as compared to normal concrete. Table 7 also demonstrates the compressive strength of specimens for 56 days. On adding waterproofing agent SBR for making M20 grade concrete the compressive strength of the specimen SBR is found to be less as compared to WC and nearly 3.5% compressive strength is decreased in the case of SBR. On adding AC+SBR the compressive strength is reduced by about 11%. The compressive strength of specimen AC is reduced by about 20% as compared to normal concrete. For SBR + NR, the compressive strength is reduced by about 37%. For AC + NR, the compressive strength is reduced by about 38% as compared to normal concrete because the incorporation of latex reduces the evaporation of water from the modified concrete, water permeability and shrinkage. It was also found to increase air entrainment thus reducing the compressive strength. The compressive strength value is less altered at 56 days as compared to 28 days.

4.2. Ultrasonic Pulse Velocity (UPV)

The ultrasonic pulse velocity test involves the measurement of electronic wave velocity through concrete. This test is used to determine the quality of concrete. Ultrasonic pulse velocity was performed on concrete containing SBR, ACRYLIC 10% by the weight of cement and combination of SBR + AC (5% + 5%), SBR + NR (5% + 5%), AC + NR (5% + 5%) by the weight of cement and WC containing no latex at the age of 28 and 56 days. The ultrasonic pulse velocity is carried out according to IS 13311 (PART 1): 1992 as shown in Table 8. UPV test is a non-destructive method of testing concrete quality (homogeneity) and this concrete cube can be further used to find compressive strength in the compressive testing machine. The density and modulus of elasticity of aggregate also significantly affect the pulse velocity.

Table 8. Ultrasonic pulse velocity

Variation of ultra-sonic pulse velocity with 10% of SBR, AC, and combination of SBR + AC (5% + 5%), SBR + NR (5% + 5%), AC + NR (5% + 5%) has been shown in Figure 12.

Figure 12. Variation of ultrasonic pulse velocity

It has been found from Figure 11 that the ultrasonic pulse velocity (UPV) value decrease by adding latex to concrete. The value of ultrasonic pulse velocity in the case of natural rubber latex-modified concrete is minimum and in the case of SBR, the value is less altered as compared to the normal concrete (WC) [28]. In the case of SBR+AC, the value is further reduced and is less than SBR. The value of AC is less as compared to SBR+AC. The value of SBR+NR is less than AC. In the case of AC+NR, the value is more affected and is found to be minimum as compared to other specimens.

4.3. Rebound Hammer Test

The experiment was performed on a specimen at the age of 56 days to assess the uniformity of the concrete and to determine the compressive strength of the concrete by relating the rebound index and the compressive strength. The results obtained for the rebound hammer test are tabulated in Table 9. The variation of the different specimens of the rebound hammer test is shown in Figure 13.

Table 9. Rebound hammer of specimen

Figure 13. Variation of rebound hammer of specimen

It is concluded while adding latex to modified concrete, the value or rebound hammer test gets reduced. In the case of SBR, the variation of rebound number is very less as compared to other latex. In the case of SBR and SBR+AC, the value is the same and is 29% less than the normal concrete. In the case of AC, the value is reduced by 35%. For SBR+NR the value is reduced by 42% as compared to normal concrete. In the case of AC+NR, the value is 21.

4.4. Permeability

A water permeability test has been performed on various specimens at 28 days and 120 days of curing. The result of the test is tabulated in Table 10.

Table 10. Coefficient of permeability of concrete

Figure 14 demonstrates that the coefficient of permeability at the age of 28 days of SBR specimen is reduced and is found to be the least among all. While adding AC the permeability value is reduced as compared to the normal concrete, but the coefficient of permeability is more than the SBR specimen. On adding natural rubber with a combination of SBR and AC the value of the coefficient of permeability is more as compared to the normal concrete specimen. In the case of SBR, the value of the coefficient of permeability is reduced by about 63%. For SB+AC the value is reduced by about 44%. In the case of AC, the value is reduced by 30%. For SBR+NR negative value is found. In the case of SBR+NR, the value is increased by about 23% as compared to normal concrete. For AC+NR the value also increased by about 35%. Figure 14 also demonstrates that the coefficient of permeability at the age of 120 days of SBR specimen is reduced and is found to be the least among all. In the case of SBR, the value of the coefficient of permeability is reduced by about 54%. For SB+AC the value is reduced by about 44%. In the case of AC, the value is reduced by 26%. In the case of SBR+NR, the value is increased by about 24% as compared to normal concrete. For AC+NR the value is also increased by about 39%.

Figure 14. Variation of coefficient of permeability of specimens

5. Conclusions

In this paper, the effect of SBR, AC, and NR on concrete its permeability and the physical/mechanical properties of latex-modified concrete were investigated. In the experiment, it is identified that on adding SBR (10% by the weight of cement) to concrete the compressive strength of latex-modified concrete nearly 05% is reduced as compared to the normal concrete. On adding SBR + AC (5% + 5% by the weight of cement) to concrete the compressive strength of latex-modified concrete by nearly 15% is reduced as compared to normal concrete. On adding AC (10% by the weight of cement) to concrete the compressive strength of latex-modified concrete nearly 20% is reduced as compared to normal concrete. On adding SBR + NR (5% + 5% by the weight of cement) to concrete the compressive strength of latex-modified concrete by nearly 40% is reduced as compared to normal concrete. On adding AC + NR (5% + 5% by the weight of cement) to concrete the compressive strength of latex-modified concrete by nearly 44% is reduced as compared to normal concrete. On adding SBR (10% by the weight of cement) to concrete the permeability of latex-modified concrete nearly 60% is reduced as compared to normal concrete. On adding SBR +AC (5% + 5% by the weight of cement) to concrete the permeability of latex-modified concrete by nearly 44% is reduced as compared to normal concrete. On adding AC (10% by the weight of cement) to concrete the permeability of latex-modified concrete nearly 30% is reduced as compared to normal concrete. On adding SBR +NR (5% + 5% by the weight of cement) to concrete the permeability of latex-modified concrete by nearly 23% increased as compared to normal concrete. On adding AC + NR (5% + 5% by the weight of cement) to concrete the permeability of latex-modified concrete by nearly 35% is increased as compared to normal concrete. Based on analysis and comparison of the findings of the experiment it is concluded that by adding styrene butadiene rubber (SBR) (10% by weight of cement) the compressive strength is only reduced by 5% which is least in comparison to other scenarios and also the permeability is reduced 60%, which is also the most effective in comparison to the selected scenarios.

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