Bugholes in concrete. It also avoids cold joints.

Bugholes in concrete The air-entrained concrete is colored with Question: What precautions should I take if my concrete has a low water-cement ratio? Answer: If the concrete you are casting has a low water-cement ratio, more mixing time will ensure that water and air bubbles are forced away from the aggregate and thereby eliminate the voids on the casting surface. Bugholes are surface imperfections that appear as small pits and craters on concrete surface after the casting process []. Reinforcing congestion concrete. In cold regions, the lining concrete of a road tunnel is exposed to de-icer solutions splashed by traffic, and We've got problems with bugholes in an 8-inch-thick architectural concrete wall that we're building. Guide Specification for Architec-tural Precast Concrete, PCI Design Handbook, fourth edition, Precast/Prestressed Concrete Insti- Jan 6, 2021 · Bugholes, considered an aesthetic problem, generally appear on concrete surfaces. The black pixels in this photographic image show the bugholes distributed on the concrete surface (Fig. Fine Cracks bubbles in the surface of formed concrete during placement and compaction. Concrete Construction Troubleshooting Tips – The Aberdeen Group 2. The results showed that the Oct 30, 2017 · The mix proportions of concrete are related to the rheology of concrete. Bugholes. jk. Oct 1, 2024 · Cracks and bugholes are common factors affecting the quality of concrete surface, thus automatic detection of apparent defects is essential for concrete surface quality assessment. The “Below-Grade Waterproofing Manual,” Apr 1, 2021 · Concrete is ubiquitous in the modern construction and building industry, bugholes are one of the most typical imperfections on concrete surface, and traditional manual inspection techniques are Oct 3, 2016 · Filling bugholes or air holes. Shrinkage Cracks. Possible reasons for bug holes in your concrete are very briefly explai cracks and bugholes on concrete surfaces. The photos show smooth-form-finish concrete with varying numbers and sizes of bugholes. Bugholes are generally caused by too much An epoxy based patching compound for filling surface defects and bugholes in concrete substrates. [highlight]bug holes (also known as surface air voids)[/highlight]—small regular or irregular cavities, usually not exceeding 15 mm in diameter, resulting from entrapment of air bubbles in the surface of formed concrete during placement and consolidation. Ceco Concrete is hard at work! We are currently providing framework services for the Ithacan Development (formerly Rothschild) in Ithaca, NY. 2. To prevent bug holes, follow the ACI (American Concrete Institute) published vibration 🕑 Reading time: 1 minute Concrete is known to be a very versatile and reliable material, but some construction errors and construction negligence can lead to the development of defects in a concrete structure. voids (bugholes) are acceptable. Three main factors contribute to this condition, improper vibration practice, non-permeable formwork and mix design. Fill molds as gently as possible. Even the best epoxy adhesive don't last that long when attached to concrete in the field. As the concrete swells, the intra-aggregate bonds at the surface of the concrete weaken and break. Kenney and Brian P. With each successive lift, the vibrator must penetrate the previous lift area. Apr 10, 2021 · Also Read: Blisters in Concrete. Apr 15, 2017 · It can be seen from Fig. Various surface penetrants have been widely used to protect concrete from environmental corrosion. Bugholes are broadly divided into four types: entrapped air voids and entrained air voids, which occur because there is no moisture inside, and gall pores and capillary pores, which contain moisture May 25, 2021 · Bugholes are small, visible holes on the concrete surface caused due to the migration of entrapped air to the fresh concrete-form interface. 3 mm and 1 mm in diameter), without missing them. Such surface imperfections may accelerate the ingression of liquids and chlorides. Firstly, in the decoder, the 3 × 3 convolution of the feature fusion part is improved to a 3-layer depth separable convolution to reduce the information Jun 16, 2019 · A deep convolutional neural network for detecting bugholes on concrete surfaces was developed, by adding the inception modules into the traditional convolution network structure to solve the problem of the relatively small size of input image and the limited number of labeled examples in training set. 16 (a) is obviously higher than that in Fig. We need a yardstick for rating concre t e s u r faces with respect to bugholes and more know - h o w on how they can be better controlled. The wetter the mix, the fewer holes generally. 3R-13),” American Concrete Institute, Farmington Hills, MI, 2013, 17 pp. Over vibrating causes air bubbles to come out of mix, and “bugholes” to form. Imagine you’re heading to battle—gear up! Goggles: Protect those peepers! A little concrete dust in your eyes can lead to a no-fun day. Mix the concrete well with the SP. 3%, but the amount of large bugholes in Fig. 4 Details of Aug 12, 2020 · Image Processing (IP) technique was used not only to detect the bugholes, but also to determine the area of bugholes in hybrid concrete. Cause: Air entrapped during concrete placement and consolidation. Oct 20, 2009 · Dik, Each of those terms is defined in ACI SP-19 "Cement and Concrete Terminology" and in ACI 116 "Cement and Concrete Terminology". and thus affect the durability of concrete. Typically, these bug holes are associated with unfinished concrete as an element to be avoided, but ConcreteWorks East has turned the tables and has begun incorporating the bug hole finish in our architectural concrete. Pinholes vary in size and physical Nov 2, 2024 · Noise reduction is a key process in digital image detection technology for concrete cracks and bug-holes. If it is just surface level with no exposed rebar, it most likely has not affected it structurally. These surface defects manifest themselves mostly in vertical surfaces. ” If the term “surface defects” included bugholes, a saw cut would be required around each one, which is clearly an unreasonable and literally impossible task. ACI 116 – Cement and Concrete Terminology – American Concrete Institute 3. n Avoid ‘sticky’ concrete mixes, eg ones that may be over-sanded or have a high percentage of air-entrainment, and mixes that are too lean. Tap outside of mold. 3. Chloride penetration is of crucial concern for reinforced concrete in a saline environment. In the 1970s, construction professionals attempted to assess concrete surface quality by manual counting the number and measuring the diameter of bugholes and then calculating percentage of holed areas on the surface, which was considered time consuming and A community designed to promote discussion between members of the concrete industry while simultaneously serving those outside the industry through its member's career acquired knowledge. The pitting is caused by water or salt infiltrating through the surface of the concrete, or if the concrete is exposed to air or extreme temperatures. Jun 2, 2014 · One of the primary influences affecting the surface aesthetics of concrete is bug holes. Mixes that are properly designed Nov 27, 2012 · Bug holes, also known as surface voids, are the little cavities that appear on concrete caused by water or air during the concrete casting process. Larger holes in concrete formed by air bubbles are called “bugholes”. While often considered minor imperfections, they can impact the structural integrity and aesthetics of the concrete if not properly managed. Ken-ney, “Problems and Repairs in Tilt-up Construction,” Concrete Interna-tional, June 1986, pp. I added fiber to mine to help ensure they dont crack. The adverse effects of the bugholes on the surface quality of concrete had been recognized very early, and bugholes on concrete surface are different to be completely avoided [1,2]. Mask: Using a mask keeps concrete dust at bay. I’ve seen concrete honeycomb patched as the forms are being pulled off with very green concrete, and patched months later. Reactive fatty acid and or methyl esters react Apr 15, 2002 · Another suggestion, from ACI 309, Guide for Consolidation of Concrete, is a procedure that has provided surfaces nearly free of bugholes in precast work: continuously placing ribbons of concrete 2-4 inches (50-100 mm) thick while continuously vibrating it. established an image-based method that is particularly suited for detecting bugholes on the concrete lining of tunnels [4]. Bugholes is a term used to describe small holes (less than about 0. … Nov 1, 2019 · Due to the influence of bugholes on the surface quality of concrete, the methods for the detection of bugholes established very early. 25 inch in diameter) that are noticeable on the surface of the concrete. How to Cure Bugholes in Concrete? Proper vibration of concrete by having lift after every concrete placed. These defects in concrete structures can be due to poor construction practices, poor quality control or due to poor structural design […] Mar 11, 2022 · The detection and evaluation of concrete surface bugholes are among the main tasks in implementing concrete quality control. [1] [2] [3] Bugholes are undesirable, as they may compromise the structural integrity of concrete emplacements. 4: Reduction of Concrete Cover due to Reinforcement Movement 7. Bugholes or surface voids are small cavities that can form in vertical cast-in-place concrete, such as walls and columns, due to the entrapment of air bubbles during placement and consolidation. 3. The concrete mix Wo r kability of the concrete mix affects the occurre n c e of surface blemishes. Bug holes occur when air becomes trapped between fresh concrete and forms. The factors influencing the formation of bugholes include the vibration,workability,mix proportions, form- Oct 1, 2017 · Bugholes are surface voids that result from the migration of entrapped air to the fresh concrete-formwork interface. ”4 However, if bugholes are not acceptable in architectural formed concrete, ASCC concrete contractors recommend specifying a rubbed finish. Zhou et al. It also avoids cold joints. " Air While some air is necessary to avoid damage when the concrete experiences freezing and thawing temperatures, too much causes blisters or bubbles on the surface that then erupt into holes. Minimizing bug holes through proper form preparation, controlled concrete pouring, vibration techniques, and mix design selection can produce high quality surfaces more cost-effectively than only by its effect upon the concrete itself, but also by its influence upon the workmen. Jun 16, 2019 · Bugholes are surface imperfections that appear as small pits and craters on concrete surface after the casting process. Concrete pitting is a type of damage that can occur in concrete, causing shallow holes in the concrete slab. Bug holes, or air voids, form on the surface of concrete as it cures. ACI 347-04, “Guide to Formwork for Concrete,” defines bugholes, or surface voids (blowholes), as small The American Concrete Institute (ACI) is a leading authority and resource worldwide for the development and distribution of consensus-based standards, technical resources, educational programs, certification programs, and proven expertise for individuals and organizations involved in concrete design, construction, and materials, who share a commitment to pursuing the best use of concrete. The combination of proper vibration techniques and the proper mold release agent can produce a glass-like concrete finish. This leads to the conclu-sion that bugholes aren’t surface defects. If bugholes have already occurred on your concrete surface, there are two ways to repair them. Bugholes Troubleshooting Concrete Surface Defects: Causes, Prevention, and Cure A separation along a plane parallel to a surface. Precast concrete products that have a cylindrical shape are less likely to retain the air and water that create bug holes than a mold that is flat on the side and more than one to two inches high. This mini-mizes slump loss, excessive mixing of concrete, and color variations. How To Fix Existing Holes in a Concrete Wall. Then, clean it up well. ACI Committee 347, “Guide to Formed Concrete Surfaces (ACI 347. n Place concrete at a rate such that its rise up the form is not less than 2 m/h vertically. developed a method incorporating gray processing, contrast enhancement, and Otsu threshold technologies to study the characteristics of bugholes distributed on concrete [18]. place the concrete in the correct lo-cation without altering the quality of the concre t e . The results obtained by Kwasny et al. They are caused by excess release agent, water, or air becoming trapped against the mold surface. org also called surface air voids, are small regular or irregular cavities, usually not exceeding 5⁄8 in. This would let the entrapped air to moved vertically up and towards form. You have to fix those cracks and holes first. Sounds like honeycombing, at least that’s what they call it around here. Prepare for your concrete adventure like a true professional. These imperfections appear as regular or irregular pits with diameters ranging from few millimeters to 15 mm in diameter and are usually scattered randomly around the surface of the concrete. ” http://www. 16, the bugholes area ratio of two concrete surfaces is 1. In this study, the threshold range of the flood-filling noise reduction algorithm was investigated experimentally. Expansion joints between home sections are another invitation to pests, as is any area where pipes or wires enter the house. Introduction. Mix considerations The concrete mix must satisfy the p r oject specifications and Before painting concrete, it's super important to prep the surface. When these molds are being filled with concrete and vibrated, the air and water in the concrete need to escape with the vibration. Sep 11, 2015 · Rock pockets, form seams and other such discontinuities are beyond the scope of this Technical Note. (16 mm), resulting from entrap-ment of air bubbles in the surface of formed con-crete during placement and consolidation. place concrete surfaces. Where appearance of the concrete is very important, hand spading next to the form may be helpful. Don’t choose concrete with low workability, S5 or SCC are always the best choice. The permissible size or number of bugholes isn’t defined for the smooth-form finishes described in ACI 301-99, “Specifications for Structural Concrete. Proper consolidation of concrete using internal or external vibrators typically removes the majority of entrapped air. com Jan 27, 2020 · Bugholes in concrete: Causes and Cures. This is very common in highly porous concrete, such as concrete with a high water-cement ratio or inadequate curing process. If your concrete surface has exposed sand grains, the appearance of the grout will be too different from the appearance of the concrete. Make sure it's all smooth and ready for painting. Concrete Construction Home page| Concrete Construction Magazine Concrete popouts occur when the microscopic air bubbles trapped in the concrete rise and cause the concrete to swell. Jump to Latest You say the concrete is cured, so the option now is a grout rub, 1 part portland cement, and 1 1/2 part sand with honeycombing should be repaired to prevent further deterioration of the concrete surface. Nov 10, 2020 · When working on a concrete structure where aesthetics are important, extra care needs to be taken to prevent bug holes. "All Grifcote products are chemically formulated to help reduce the formation of bugholes. Cracks and bug holes mess up how it looks and how long it lasts. Use permeable forms to make the air voids move to the Are bug holes in concrete a cause for concern? This article delves into the formation, implications, and aesthetics of bug holes, exploring whether they signify serious structural issues or are just cosmetic flaws. 4. Feb 9, 2016 · From the Portland Cement Association site,"Bugholes are surface voids that result from the migration of entrapped air (and to a lesser extent water) to the fresh concrete-form interface. If bugholes aren’t acceptable—because an archi-tectural finish is desired or because the concrete Jan 31, 2024 · Filling holes in concrete is an essential maintenance task that addresses both the structural integrity and aesthetic appeal of concrete surfaces. 24 cylinders with six different mix ratios were cast with 0 Bug holes (also called blowholes or air voids) in concrete are small, surface-level cavities formed when trapped air or water is not fully expelled during th Nov 2, 2024 · RC Bridge Concrete Surface Cracks and Bug-Holes Detection Using Smartphone Images Based on Flood-Filling Noise Reduction Algorithm November 2024 Applied Sciences 14(21):10014 Oct 8, 2013 · It can be tricky to pour successfully, so it's important to avoid several issues that can cause the appearance of bubbles and pits known as "bugholes. Traditionally, project managers and inspectors mainly rely on human visual methods to evaluate the surface quality of concrete, which is subjective and inefficient. The Concrete,” Aberdeen’s Concrete Re-pair Digest, June/July 1992, pp. 1. Gloves: Keep those hands safe. As the concrete heats up, the air forces itself through the membrane or coating causing the pinhole. 2 (a). I also added color to my concrete. “ASCC Position Statement #8: Bugholes in Formed Concrete,” Aug 3, 2021 · Of course this calls for very skilled labour to properly compact the concrete without incurring in honeycombs. When concrete is placed into a form it is common for air to be entrapped between the side of the form and the placed concrete. You may never have heard of us, but you've seen our products at work. Simple outgassing of concrete, covered in pinhole resolution, is beyond the scope of this Technical Note. Allan R. However, if concrete is not adequately consolidated excessive bugholes will occur. Discover essential tips to A bughole (or pinhole) is a small hole in the surface of a concrete structure caused by the expansion and eventual outgassing of trapped pockets of air in setting concrete. These unsightly surface voids occur when air is trapped between the form and the fresh concrete. See full list on constructioncivil. ” These very small imperfections in the concrete cannot be easily filled with membrane or coating, and air is typically trapped inside them. Definitely some variation panel to panel. They normally occur in vertical cast-in-place concrete surfaces. Bug holes are small, pock-mark-like openings on a concrete surface. 1) Surface voids, also known as bug holes or pitting, are small cavities or holes that appear on the surface of concrete castings. By taking proactive steps…. If bugholes aren’t acceptable—because an archi-tectural finish is desired or because the concrete Apr 26, 2021 · Liu et al. However, most previous research on Expert Guidance & Custom Solutions – Tailored recommendations for specific concrete applications. 89-92. Design and Control of Concrete Mixtures – 7th Edition – Cement Association of Canada Bugholes (Surface Air Voids) Bugholes on a plywood formed surface Bugholes on a concrete surface created with Apr 15, 2017 · The fair-faced concrete requires that the maximum diameter of bugholes is no more than 8 mm, the depth is no more than 2 mm, and the area ratio of bugholes is no more than 20 cm 2 /m 2 (the area ratio of bugholes no more than 0. Sep 16, 2012 · It is not so much of a concern on countertops, but the coefficient of thermal expansion is very different between concrete and polyester resin. The formation of shrinkage cracks in concrete structures is due to the evaporation of water from the concrete mixture. In this video we mix cement at a ratio of 2 parts sand to 1 part cement, add a small amount of concrete. Nov 1, 2019 · Due to the influence of bugholes on the surface quality of concrete, the methods for the detection of bugholes established very early. However, I believe wetter concrete mixes tend to be weaker. You can fill small voids using a concrete grout in many cases. [40] created a dataset of concrete bugholes and the semantic segmentation model DeepLabV3+ [41] to segment bugholes. The two defects included in those images are labeled manually. Reply Delete Form condition, concrete placement methods, and mix properties can impact the formation of bug holes in concrete surfaces. b for a smooth-form finish instructs the contractor to Filling bug holes in concrete ornaments, statuary and pieces. Poured concrete is the most reliable, but if you have a block foundation, the mortar is likely to provide open spaces. PROBLEM: Formed concrete wall surfaces are prone to produce pinholes [also known as bugholes]. Use the vibrator in the wheelbarrel and you will see bubbles come out of the mix. You Concrete- Most often in concrete there are voids in the surface which are termed, “bug holes. cement. Jul 18, 2016 · It only takes a small crack in an otherwise secure concrete foundation to let termites in. 2 (b)). In the case of a concrete slab, a horizontal splitting, cracking, Jun 1, 2018 · A typical image of a concrete surface with bugholes is shown in Fig. More recently, Yoshitake et al. But whatever they’re called, sometimes you may need to fill larger holes with grout. [6] show that an increase in the water-cement (W/C) ratio and the superplasticizer (SP) content decreases the yield value, whilst the increase in the sand content has an opposite effect, and an increase in the yield value is found to increase the total content of the surface bugholes Nov 1, 2015 · However, the impact of surface bugholes on concrete durability is still unidentified. The top half of my basement walls have quite a bit of of what looks to be air pockets when they poured the concrete. delivers top-quality Concrete Form Oils that ensure optimal performance, cost savings, and exceptional concrete finishes. These oddly-named voids ar e pests to precast producers everywhere as they are unsightly holes left on the outer surface of concrete products. Jun 16, 2023 · Bug Holes Diagnosis: Also known as blow-holes, bug-holes are small air-bubble voids on the surface of formed concrete. 8, “Bugholes in Formed Concrete,” and “Guide for Surface Finish of Formed Concrete,” most bugholes are not surface defects. This product uses an epoxy resin and a unique, inert mineral filler to achieve a smooth non-slumping fill material. The American Concrete Institute (ACI) is a leading authority and resource worldwide for the development and distribution of consensus-based standards, technical resources, educational programs, certification programs, and proven expertise for individuals and organizations involved in concrete design, construction, and materials, who share a commitment to pursuing the best use of concrete. They occur when air bubbles trapped in the concrete mix escape before the concrete hardens. Whether it’s a sidewalk, driveway, or interior floor, imperfections can compromise the strength and durability of the concrete, potentially turning into safety hazards over time. They are typically the result of too much sand concrete mixture, or too much amplitude of vibration during placement. With a total of 4 levels of structural concrete and 2 sets of core walls that rise 15 lifts each, check in on the progress of this project with this awesome video captured by Lehigh Hanson. 2) To eliminate surface voids, concrete casters should carefully prepare molds, use a proper release agent, increase mortar content, add plasticizers, smooth mold Poor finishing of concrete results in the spalling of concrete from surface early in their service life. A workman functioning under poor conditions can be expected to perf o r m ac-c o rd i n g l y. The American Concrete Institute (AC I ) is doing eve r ything possible to p r omote re s e a r ch to solve this of concrete products help eliminate bugholes. 41-50. Oct 30, 2017 · The mix proportions of concrete are related to the rheology of concrete. bugholes are a natural feature of all as-cast vertical concrete structural components, it is unrealistic to expect that surfaces will be free of bugholes. The concrete will shrink and swell with temperature much more than the bondo. Perhaps the most influential cause of bugholes is improper vibration. This Sashco sealant from Amazon is highly effective and easy to use. [6] show that an increase in the water-cement (W/C) ratio and the superplasticizer (SP) content decreases the yield value, whilst the increase in the sand content has an opposite effect, and an increase in the yield value is found to increase the total content of the surface bugholes Sep 20, 2024 · Concrete bugholes refer to surface pores created when air trapped in concrete moves to the surface in contact with the newly cast concrete mold. 2%), the evaluation parameters mainly includes the maximum diameter, depth and area ratio of the bugholes [25], [26]. This study proposes an automatic quality assessment method based on deep learning for concrete surfaces with different scales of cracks and bugholes. 5. Bug holes are surface voids that result from the migration of entrapped air (and to a lesser extent water) to the fresh concrete-form interface. Depressions in the concrete surface, namely bugholes, are relatively dark because of their shadows and are processed as black by the binary image analysis. Think of them as the concrete’s version of acne – they’re not pretty, but they happen. I assume some of these are normal, but it seems Jun 10, 2021 · To use this method, a database is built containing 16,662 256 × 256 pixel images of bugholes and cracks on concrete surfaces. Make a row of vibrator insertions as close to the form as possible, but without touching the form. In the 1970s, construction professionals attempted to assess concrete surface quality by manual counting the number and measuring the diameter of bugholes and then calculating percentage of holed areas on the surface, which was considered time consuming and Sep 24, 2020 · Finding bug holes or too many bug holes in your concrete castings can be a real pain. Dec 9, 2024 · Fig. This video expla Concrete Practice (ACI 303R-12),” American Concrete Institute, Farmington Hills, MI, 2012, 32 pp. Jun 16, 2019 · 1. Schedule and dispatch concrete to arrive just before needed. But two publi-cations dealing with concrete waterproofing and coating products require substrates with a surface smoother than that defined for a smooth-form finish. Jan 30, 2025 · Cracks and bugholes are common factors affecting the quality of concrete surface, thus automatic detection of apparent defects is essential for concrete surface quality assessment. Learn about their common causes, prevention techniques, and effective repair strategies to maintain the durability and beauty of your concrete surfaces. It's 4 to 6 feet high and the surface looks fine, except in the top 1 foot where lots of bugholes have formed. If you've ever been to the movies, admired a piece of sculpture, marveled at detailed architectural ornamentation or used a telephone; then you've encountered the handiwork of people who use Smooth-On rubbers, plastics, foams and other products to turn their ideas into 3-dimensional reality. Repair of spalling involves removal of defective concrete and replacement with epoxy bonded concrete. The concrete must be well mixed so take into consideration a little extra time to do this. 16 (b), therefore the parameters of bugholes area ratio cannot fully evaluate the surface bugholes of concrete, the size distribution of bugholes must be considered for the Reduce the distance between internal vibrator insertions and leave the vibrator in the concrete longer. However, the actual segmentation results were biased due to limitations in network What Causes Bug Holes In Concrete? In this informative video, we'll take a closer look at bug holes in concrete, those small voids that can appear on the sur About Smooth-On, Inc. Surface cracks and bug-holes in RC bridge concrete were detected using mobile terminal images based on the flood-filling noise reduction algorithm. n ensure that the member is adequately compacted (see Compaction of Concrete data Concrete consolidation in the 21st century ACI Spring bugholes –Costly, difficult and time consuming remedial work Introduction. Consolidation, usually through vibration, sets the air and water bubbles into motion. The influencing factors, such as mix proportions and construction technology ABOUT THE INTERNATIONAL CONCRETE ABSTRACTS PORTAL. Why Do Bug Holes Form in Concrete During Curing, and Are They Harmful? May 20, 2020 · Bugholes are very small air bubbles that become entrapped in the concrete mixture and then make their way to the concrete surface. That's why getting it ready is key. None have cracked in the 3 years theyve been up. Oct 1, 2024 · This method could effectively detect bugholes, especially small bugholes (between 0. This leads to arguments between the contractor and owner. The type of grout used will vary based on the size and depth of the holes. ” Section 5. The International Concrete Abstracts Portal is an ACI led collaboration with leading technical organizations from within the international concrete industry and offers the most comprehensive collection of published concrete abstracts. The traditional measurement methods are carried out by in situ manual I used a sazall without a blade. Feb 27, 2021 · One of the primary influences affecting the surface aesthetics of concrete are bugholes. Bugholes are surface imperfections that appear as small pits and craters on concrete surface A vinyl ester based patching compound for filling surface defects and bugholes in concrete substrates. Whether you’re working on large-scale infrastructure, commercial buildings, or decorative concrete projects, Taylor Oil Co. Nobody wants concrete burns; it’s like a bad Tinder date. Mar 1, 2020 · ABOUT THE INTERNATIONAL CONCRETE ABSTRACTS PORTAL. nafs wiuyrvg uaclx zeqblk dop wcszsc dpnxe xrdoenqn ili dkz uzbgls gid lny aufq ipyh