Fiber Pullout-қа ренжіді? Жақсырақ байланыс беріктігі үшін беттік өңделген PVA талшығын қалай пайдалану керек

Менің бірінші жобам сәтсіз аяқталды. Міне, мен нені білдім.

Жарылған сынақ сәулесіне қарап тұрғаным есімде, көңілсіз. Біз стандартты PVA талшығын қолдандық, Инженерлік цементті композит күтілуде (ECC) сиқыр. Оның орнына, we got fiber pullout-clean, smooth holes where талшықтар had slipped out.

Таныс естіледі? Many of us have been there. The promise of PVA талшық is huge, but only if it bonds. That’s why we need surface treated PVA fiber for better bond strength. Let’s walk through how to fix this, step by step.

Why Does Standard PVA Fiber Fail to Bond?

Untreated PVA fiber is smooth and гидрофобты. It floats in the mix. It doesn’t grab onto the cement hydration products. Нәтиже? Low pullout resistance. Your composite cracks, and the fibers just slip out. No toughness. No crack control.

We need a rough, reactive surface. That’s the goal of every surface treatment.

How Does Surface Treated PVA Fiber Improve Bond Strength?

The mechanism is simple chemistry. Treatment creates functional groups on the following:

• Rougher surface: More mechanical interlocking with the cement matrix.
• Chemical hooks (функционалдық топтар): Hydroxyl or carboxyl groups that form hydrogen bonds with calcium silicate hydrate (C-S-H) гель.
• Better wettability: The fiber absorbs water, shrinking slightly, creating a tight frictional grip.

Бұл теория емес. It’s proven pullout resistance increases by 40-80% depending on the method.

Қадам 1: Choose Your Surface Treatment Method

Don’t just dump fibers in and hope. Pick a method. Here are the three we see most in the field:

Plasma Treatment (Best for Control)

Cold atmospheric plasma bombards the fiber surface. It cleans it. It adds oxygen-containing groups. Result: a highly reactive surface. The downside? You need specialized equipment. It’s not a bucket-and-stick job.

Silane Coupling Agents (Best for Chemical Bonding)

We mix aminosilane or similar compounds in a water-alcohol solution. Dip the fibers. Dry them. The silane forms a molecular bridge between the organic fiber and inorganic cement. This is the most common field method. Ол сенімді.

Alkali Treatment (Cheapest, but Tricky)

Soak fibers in a sodium hydroxide bath. This removes surface impurities and creates pits. Сақ болыңыз. Over-treatment degrades the fiber itself. We recommend 1-2% NaOH for 30 минут. Test a batch first.

Қадам 2: Optimize Your Parameters (Don’t Skip This)

Temperature and time matter. A lot.

• Plasma: 2-5 minutes exposure. Too long, and you burn the fiber.
• Silane: pH of the solution should be around 4.5-5.5 for hydrolysis. Let it react for 24 hours before use.
• Alkali: Room temperature is fine. Higher temps accelerate etching but weaken the core.

Қадам 3: Check Workability and Dispersion

Here’s a common complaint: “Treated fibers ball up.” Иә, they can. Surface treatment can make fibers sticky.

Мұны түзету үшін, we add a small amount of mineral oil (0.1% by fiber weight) after treatment. Or we use a high-range water reducer (суперпластификатор) қоспада. The key is to add fibers slowly to the mixer. Don’t dump them in. Sprinkle.

Many users on Reddit report that treated PVA fibers actually disperse better than untreated once they wet-grade fibers once the mix is properly sheared. The roughness stops them from clumping as they untangle.

Treated vs. Untreated: The Real-World Difference

We ran a comparison last year.

• Untreated PVA: Flexural strength 8 МПа. Multiple cracking? Barely. The beam failed by pullout.
• Silane-treated PVA: Flexural strength 14 МПа. Saturated multiple cracking. The fiber broke, not pulled out. Toughness tripled.

That’s the difference between a brittle composite and a ductile one. үшін жоғары өнімді бетон және жөндеу ерітінділері, this is non-negotiable.

What About Durability? Freeze-Thaw and Shrinkage?

Better bond means better crack control. If the crack width stays below 50 микрон, water and chlorides can’t penetrate. That’s the secret to мұздату-ерітуге төзімділік.

Surface treated fibers also reduce drying shrinkage. They physically restrain the matrix. We’ve seen shrinkage reduction of 30-40% in ECC mixes using treated fibers.

Which Applications Benefit Most?

• Инженерлік цементті композиттер (ECC): The bread and butter. Treated fibers are required for strain-hardening.
• Жоғары өнімді бетон (HPC): For bridge decks and impact zones.
• Жөндеу минометтері: Good bond with the substrate means a repair that lasts.
• Thin overlays: No place for weak bond. Every fiber counts.

Сіздің келесі қадамыңыз: Start Testing Today

Don’t settle for mediocre fiber performance. The standard wet-grade PVA fiber is not designed for bond. Сізге керек surface treated PVA fiber for better bond strength.

We recommend starting with a silane treatment. It’s the most field-proven and forgiving method. Buy a small batch of treatable fiber, follow the steps above, and run a pull-out test. You’ll see the difference immediately.

Ready to skip the trial and error? We pre-treat PVA fibers using our proprietary silane plasma hybrid process. Consistent, batch-tested, ready to mix. Contact us for a sample pack. Your composite will thank you.

Жеткізуші
ConcreteAndMore – жоғары өнімді бетон қоспалары мен құрылыс химикаттарының сенімді жаһандық жеткізушісі. Көп жылдық салалық тәжірибемен, біз инновациялық шешімдерді, соның ішінде поликарбоксилатты суперпластификаторларды ұсынуға маманданамыз, бетон талшықтары, көбік кетіргіштер, көбік түзетін заттар, және озық аэрогельді жылу оқшаулау өнімдері. Егер сіз бетон қоспасына қызығушылық танытсаңыз, бізге хабарласыңыз!