Ar īsām šķiedrām armētas kompozītas sijas. Neitrālas līnijas stāvoklis intensīvas plaisāšanas laikā

Tērauda šķiedru fibrobetons ir mūsdienīgs konstruktīvs materiāls ar plašu pielietošanas lauku

Elastīgi-plastiskas šķiedras izraušanas modelēšana

Publikācijā salīdzināti skaitliskās modelēšanas rezultāti, raujot vienu šķiedru no elastīgas matricas, ar eksperimentālajiem rezultātiem, raujot tērauda šķiedru no augstas stiprības betona matricas. Skaitliski tika modelēta un pētīta berze starp šķiedru un matricu, kā arī šķiedras elastīgās un plastiskās deformācijas. Skaitliskās modelēšanas mērķis: novērtēt dažādu mehānisko parādību nozīmību, (piemēram, berzi, matricas rukumu, šķiedras plastiskumu) vienas šķiedras izraušanas procesā salīdzinājumā ar eksperimentālajiem datiem. Skaitliskās parametru vērtības gadījumā, kad tiek izrauta tērauda šķiedra no betona, matricas tika veiksmīgi iegūtas un analizētas

Tērauda šķiedru mikromehānika fibrobetonā

50. RTU Studentu zinātniskās un tehniskās konferences materiāl

Nesimetriskas formas šķiedras orientēšana viskozā šķidruma plūsmā

53. RTU Studentu zinātniskās un tehniskās konferences materiāl

Polymer Fiber Pull out Experimental Investigation

Advanced polymer fibers are used in structural applications as micro reinforcement in composite materials with concrete matrix. Comparing to another fibers (steel, glass, carbon etc.) polymer fibers are behaving visco-elastically or visco-elasto-plastically. Such fibers have relatively not high starting elastic modulus are characterized by relatively large elastic deformations and pronounced Poisson’s effect during stretching.

Post - Cracking Behaviour of High Strength (Nano - Level Designed) Fiber Concrete Prediction and Validation

Fracture process in mechanically loadded steel fiber reinforced high - strenth (SFRHSC) concrete is characterized by fibers bridging the crack providing resistance to its opening

Post-Cracking Behaviour of High Strength Fiber Concrete. Prediction and Validation

Fracture process in mechanically loaded steel fiber reinforced high-strength (SFRHSC) concrete is characterized by fibers bridging the crack providing resistance to its opening. Structural SFRHSC fracture model was created; material fracture process was modeled, based on single fiber pull-out laws, which were determined experimentally (for straight fibers, fibers with end hooks (Dramix), and corrugated fibers (Tabix)) as well as obtained numerically ( using FEM simulations). For this purpose experimental program was realized and pull-out force versus pull-out fiber length was obtained (for fibers embedded into concrete at different depth and under different angle). Model predictions were validated by 15x15x60cm prisms 4 point bending tests. Fracture surfaces analysis was realized for broken prisms with the goal to improve elaborated model assumptions. Optimal SFRHSC structures were recognized

Polymer Fiber Pull out Experimental Investigation

Advanced polymer fibers are used in structural applications as micro reinforcement in composite materials with a concrete matrix. Comparing to other fibers such as steel, glass, carbon etc., polymer fibers behave visco-elastically or visco-elasto-plastically. Such fibers having moderate starting elastic modulus are characterized by relatively large elastic deformations and pronounced Poisson’s effect during stretching

Polymer Fiber Pull out Experimental Investigation

All fibers bridging the crack are stretched (load is increasing- second peak on the curves). After that fibers start to rupture and its ends with friction are pulling out (curves after second peak). Relatively low polymer material Young modulus is leading to two peaks formation on the curves what wasn’t recognized for materials with high modulus fibers. Single polymer fiber is embedded into elastic matrix and was subjected to external applied pulling load was numerically simulated. Numerical modeling was performed using 3D FEM approach