This paper present the engineering properties of asphalt (AC 60/70) modified with different ratios of crumb rubber. Then select the best properties of the binder to mix asphaltic concrete. From laboratory testing results with adding 11% crumb rubber into mixtures for the best results. The properties of asphaltic concrete can be improved by adding 11% crumb rubber. For asphaltic concrete Marshall Stability increased and flow decreased with adding crumb rubber into asphalt. Comparing to ordinary asphaltic concrete (AC 60/70) the rutting resistance was increased 18% for crumb rubber modified asphalt respectively. Moreover the fatigue resistance of crumb rubber modified asphalt improved to be 1.59 times compared to AC 60/70.

This paper present the engineering properties of asphalt (AC 60/70) modified with different ratios of natural rubber. Then select the best properties of the binder to mix asphaltic concrete. From laboratory testing results with adding 6% natural rubber into mixtures for the best results. The properties of asphaltic concrete can be improved by adding 6% natural rubber. For asphaltic concrete Marshall Stability increased and flow decreased with adding natural rubber into asphalt. Comparing to ordinary asphaltic concrete (AC 60/70) the rutting resistance was increased 22% for natural rubber modified asphalt respectively. Moreover the fatigue resistance of natural rubber modified asphalt improved to be 2.06 times compared to AC 60/70.

This research to study the possibility of material pozzolan as binder by replacment cement by fly ash (FA) and meta kaolin (MK) some for testing compressive strength flexural strength and impact strength of concrete vary the ratio of water to binder (w / b) of 0.40 and 0.45 and the amount of fly ash to replace cement some 15 % 30 % MK and 35% for 10% 15% and 20% by weight of cement. The sample consisted of a cylinder diameter of 10 x 20 cm beam sizes 10 x 10 x 40 cm and 4 x 4 x 16 cm from the test results showed that the concrete samples at 28 days and w/ b of 0.40 to greater than 0.45 all mixed. the compressive strength by replacing cement with FA increase up to 30 % compression of 382 ksc higher than the 20 percent replace by MK were equal to 354 ksc and 32.48 ksc compared to replace cement with FA 15 % is equal to 31 ksc 30% were equal to 30 ksc and 45% were equal to 23.85 ksc while the MK was replaced by 10% were equal to 40.10 ksc higher than to 15% and 20% respectively. The control sample was replaced with MK by 10% is equal to 111 joules maximum replaced by fly ash more than 30% were equal to 110 joules and MK were 15% fly ash 15 and 45 percent respectively.

The aim of this research is to create the center of mass testing machine for vehicles with maximum mass 3000 kilograms. By the performance of this machine is able to determine the center of mass 3 axis by horizontal longitudinal and vertical. On the other hand the verities of mass from 50 to 100 kilograms and the several of weight distribution at horizontal and longitudinal are applied to the condition of testing for reasonable to the position of the center of mass. The result of research discovered to the performance of center of mass tester was activated following to test conditions. Furthermore the weight distribution at longitudinal was the highest effect to the horizontal center of mass. By the way the value of weight distribution at horizontal is more effects to the longitudinal center of mass. Moreover increasing of mass was impact to the vertical center of mass and it’s independent to the position of weight distribution.

The aim of this research is to study the varieties of weight density distribution affect to the center of mass and vehicle stability. The weight density distribution tester was designed and changed the position of mass. Base on the center of mass is main points of vehicle stability. On the other hand FMCSA standard was applied to field test for considering of the brake performance and vehicle stability. The results of research discovered to the mass distribution on longitudinal plane are affected to the center of mass and absolutely influence at the right wheel on the front axle. In term of the braking performance it’s depends on the lateral mass distribution especially the center position of mass installed on longitudinal and horizontal plane and close up on the front axle (Y2). For the vehicle stability results the position (Y2) is the highest influence for yaw rate and sideslip. Otherwise the position (Y3) or the position of mass installed on longitudinal plane and nearly at the left wheel on the rear axle. Additionally wheel lock-up condition was appeared on the front axle only. Because the behavior of weight distribution on the front axle was decreased lead to mass distribution on longitudinal plane.