Print ISSN: 1681-6900

Online ISSN: 2412-0758

Keywords : Self-sensing

Effect of adding additional Carbon Fiber on Piezoresistive Properties of Fiber Reinforced Concrete Pavements under Impact Load

Ayad K. Mohammed; Ali Majeed Al-Dahawi; Qais S. Banyhussan S. Banyhussan

Engineering and Technology Journal, 2021, Volume 39, Issue 12, Pages 1771-1780
DOI: 10.30684/etj.v39i12.1942

Multifunctional Cementitious Composite (MCC) characteristics are directly related to the type and dosage of the Electrically Conductive Materials (ECMs) reinforcing the relevant concrete matrices. This study investigated the electro-mechanical capacities of fiber reinforced concrete pavement (FRCP) with and without the addition of micro scale-carbon fiber (CF). The impact energy of FRCP under compacted load was evaluated initially; then, the effects of 0.5% and 1% content by volume of CF on the piezoresistivity capacities of FRCP were investigated under applied impact load. This type of load is the most common force causing long-term rigid pavement deterioration. Obtained results showed that the use of a hybrid fiber (micro-scale carbon fiber 0.5% and macro-scale steel fiber 1% by volume) enhanced the impact strength (impact energy) due to CF’s resistance to micro-cracks. The developed FRCP showed good results in terms of self-sensing under compact load with both 0.5 and 1.0% by volume of CF.

Distribution of Pressures on Modified Stepped Spillway by Using Toothed-Steps

Jaafar S. Maatooq; Ameer L. Jasim

Engineering and Technology Journal, 2021, Volume 39, Issue 8, Pages 1265-1270
DOI: 10.30684/etj.v39i8.1957

In the present study a new steeped spillway shape at which “toothed steps” have been adopted instead of traditional steps to enhance the amount and distribution of water pressure along the chute of the stepped spillway. Experiments were conducted under a skimming flow regime, on five physical models of spillway one of which consisted of traditional steps used as a base model. For all investigated models, the chute angle was 45° with fourteen steeps each of 3cm height. Generally, the results show that the new shape models enhance the pressure distribution and reducing the potential for negative pressures along the chute, as well as, reducing the values of positive pressures that usually impact the tread. Specifically, close to the crest, the differences in pressure values being clearly large between the toothed steps modelsand the traditional steps. The new configurations of steps reduce the positive pressures between 116.66% to 1.28 % and the negative pressures were generally close to zero.

Carbon Fiber-Based Cementitious Composites for Traffic Detection and Weighing In Motion

Dhurgham Ghadhban; Hasan H. Joni; Ali M. Al-Dahawi

Engineering and Technology Journal, 2021, Volume 39, Issue 8, Pages 1250-1256
DOI: 10.30684/etj.v39i8.1875

New self-sensing cementitious composites embedded in the highway pavement for vehicle detection and weigh during motion is fabricated. Smart carbon fiber (CF) reinforced cement-based materials with high sensitive property are used as sensors. These smart composites may be able to detect the traffic and sense the weight in motion, thanks to their piezoresistive property. Cement-based sensors capability to vehicle detection was investigated in a real field at the University of Technology campus. Findings clarify that the CF-Based cementitious composites provide have a great potential to use as sensors for detect traffic and its composition also it possibly identifies different vehicular axle loadings (weigh during motion).