Video from my YouTube channel

Subscribe to My You tube channel

Bitumen penetration test

By -

 The penetration test for bitumen determines its consistency by measuring how deep a standard needle penetrates the material under specific conditions of temperature, time, and load. This test, performed at 25°C with a 100-gram weight over 5 seconds, helps classify bitumen into grades like 30/40, 60/70, or 80/100. These grades indicate the hardness or softness of the bitumen, which is critical for its application in road construction and other industrial uses.





During the test, the bitumen sample is heated, poured into a container, and cooled under controlled conditions to ensure uniformity. The sample is then maintained at a constant temperature in a water bath. When the needle is applied, its penetration depth (measured in tenths of a millimeter) reflects the material's hardness or softness. Softer bitumen with higher penetration values is typically used in colder climates to prevent cracking, while harder grades with lower penetration values are better suited for high temperatures or heavy loads.

Comments

Post a Comment

Videos from My Youtube channel

Popular posts from this blog

Pile cap

By -
Image
Pile cap used to transfer the loads from superstructure to the piling. The pile cap is thick concrete mat rests on piles. It is part of the foundation and used to distribute the loads over the piles. Piles used when the soil bearing is not enough to carry loads of the structure. Figure 1  construction management: concrete construction bridge construction:How to become a bridge engineer Pile cap construction procedure Excavation around piles: After 7 days of the casting of the pile the concrete will gain approximately, 70% of it is compressive strength. The soil around piles will be removed to the required levels and dimension that allows construction of the pile cap. A step shall be made if the excavation is more than 1.5 m to prevent soil collapse. Figure 2 Pile head cutting: Concrete will be removed up to cut off level. If concrete under the cut off level is unsound. It shall be removed, and the pile will be repaired...
Read more

Bridge Diaphragm

By -
Image
The main function of diaphragms is to provide a stiffening effect to deck slab in case bridge webs are not situated directly on top of bearings. Therefore, diaphragms may not be necessary in case bridge bearings are placed directly under the webs because loads in bridge decks can be directly transferred to the bearings.On the other hand, diaphragms also help to improve the load-sharing characteristics of bridges. Diaphragms also contribute to the provision of torsional restraint to the bridge deck. Diaphragm will be used also to resist stresses that occurs during the post-tensioning process. Post-tensioning hardware are casted inside the diaphragm. Figure 1 construction management: concrete construction bridge construction:How to become a bridge engineer Types of diaphragm: Diaphragm at the span end: this type of diaphragms will be located between two bridge spans or at the bridge abutments. Expansion joints will be used to connect bridge spans. This ...
Read more

Bar Bending schedule (BBS)

By -
Image
 The bar  bending schedule is a table that contains the details of reinforcement for a specific structural member such as footing, column, slab, and others. The bar bending schedule will contain the bars' dimensions to be used, the shape of the bars, the size of bars, bar mark, number of bars, and the weight of bars. BBS will be used to determine the weight of reinforcement required for a specific structural member.  there are various advantages of bar bending schedule such as: estimating the quantity of reinforcement for each structural member. So we can estimate the amount of reinforcement required for a construction project.  BBS will help in reducing the losses of steel by procuring the precise quantity of different rebar diameter.  BBS will reduce the wastage of reinforcement by providing the engineers with the exact dimension and shape of rebars. Knowing the exact dimension and shape will reduce the time of cutting and bending rebars.  BBS will reduce...
Read more

Binding wire for steel reinforcement

By -
Image
  Binding wires are used to tie steel bars together. These wires are playing a significant role in maintaining the reinforcement stability and rigidity. Wires are used to tie the steel bars at intersections points. By tying the steel bars together, we ensure that the steel bars will not move from their locations during construction or during the time of concreting. In slabs, binding wires are used to tie longitudinal and transverse bars together. In columns, it is used to tie vertical bars with stirrups.   Figure 1 There are various types of binding wires such as  Black annealed baling wire, Stainless Steel Binding Wire, and PVC coated binding wires.  Black annealed baling wire used to tie black steel. The popular size for black wire ranges from 16 to 22 gauges. Stainless steel binding wires are used to bind stainless steel reinforcement. Stainless steel reinforcement is used in a harsh environment where the black steel gets rusted quickly. Therefore, stainless ...
Read more

Determinate and indeterminate structure

By -
Image
structure can be called determinate if the equilibrium equation provides enough and sufficient condition for equilibrium. if all forces for a structure can be determined using equilibrium equations only, this structure is determinate, but if the unknown forces are more and cant be determined using equilibrium equations then this structure is indeterminate.in general we can determine if a structure is statically determinate or indeterminate by drawing free body diagram for a structure or part of it and comparing a number of unknown forces and moment component with number of available equation of equilibrium. for coplanar structures, we have  three equilibrium equations, if n is the total number of parts and r is the number of unknown forces and moment component then: r=3*n determinate r>3*n indeterminate  construction management: concrete construction bridge construction:How to become a bridge engineer statically indeterminate structure cant ...
Read more

Repairing of concrete bulging

By -
Image
Improper designing and installation of formwork for a concrete member can result in concrete Bulging. During the placing and compacting of concrete, forms may deflect largely in the weak areas. The deflection of forms will cause concrete to expand at this location, and this known as concrete Bulging. Concrete Bulging will spoil the appearance of a concrete member. Therefore we should always ensure that the forms are appropriately installed, and it is sufficiently supported to resist the concrete during placing and compacting. Bulging should be repaired in case we couldn't avoid it. The solution of concrete Bulging, offset, or surface irregularities are surface grinding. However, excessive surface grinding can weaken the concrete.  Figure 1 If the bulging or surface irregularities are small, grinding of concrete surface will be sufficient to remove surface irregularities. If the Bulging of concrete is significant, then the concrete should be chipped, and the surface...
Read more

stress-strain diagram for aluminium alloy and rubber

By -
Image
figure no:1 showing the stress-strain diagram for aluminum alloy. we can notice from the stress-stress diagram that aluminum has a considerable ductility. despite the absence of explicit yield point as in structural steel . the initial portion of the stress-strain curve is linear with a recognizable proportional limit. the proportional limit for aluminum alloy ranges from 70 to 410 Mpa (10 to 60 Ksi). aluminum alloy undergoes large strain before failure. ultimate stress ranges from 140 to 550 Mpa (20 to 80 Ksi). construction management: concrete construction bridge construction:How to become a bridge engineer Figure-1 Yield stress for aluminum alloy can be determined by drawing offset line parrel to the linear portion of the stress-strain curve. the straight line offset by a standard strain such as 0.002. the intersection point with the stress-strain curve is the point of yield stress. figure no:2 illustrates the concept of offset method. yield stress acquire...
Read more

prestressing equipment

By -
Image
Jacks are essential tools in prestressing operations and are used to apply tension to strands within tendons. There are two main types of jacks: A. Mono-Strand Jack A mono-strand jack is primarily used in building construction, where tendons typically consist of a small number of strands (usually 3 to 4). This type of jack is designed to stress each strand individually, ensuring precise control over the tensioning process. Since buildings generally have shorter tendons compared to bridges, stressing strands one by one is a practical and efficient approach in this context. construction management: concrete construction bridge construction:How to become a bridge engineer B. Multi strands jack:  In bridge construction, where tendons contain a significantly larger number of strands, using a mono-strand jack would be impractical. Stressing strands one by one in such cases would not only be time-consuming but also increase the risk of strand entrapment. Ther...
Read more

Bridge bearing sliding material

By -
Image
Pot bearing and spherical bearing are used widely in the bridge construction industry. Pot bearing and spherical bearing composed of many components and has many functions. Pot and spherical bearing allow releasing of stresses generated due to increase and decrease of superstructure span due to thermal variation, shrinkage, and creep deformation. the Bearing will release these stresses by allowing of the superstructure translation movement in one or two directions. Figure 1 (Pot bearing) construction management: concrete construction bridge construction:How to become a bridge engineer The mechanism of bearing movement is by sliding. Sliding materials will slide against a hard mat. PTFE (Polytetrafluoroethylene) used commonly as sliding materials. Sliding material should have a low friction coefficient. PTFE possesses low static and dynamic friction coefficient, which make it very suitable to slide against hard material such as stainless steel without cre...
Read more

Chamfers for concrete structures

By -
Image
In general, the edges of concrete members are chamfered. Usually during the process of installing forms for a structural member such as pile cap, a chamfer a PVC chamfer as shown in figure no:1 installed at the edges of the structural members. These chamfers will form smooth slanted edges, as shown in figure no:2. The size of chamfers can be 20x20mm or more as shown on the contract drawing. The PVC chamfer fixed to forms by nails. We should ensure that the PVC chamfer fixed in their correct locations, and we should ensure that the PVC chamfer is straight and not moving up or down. Checking the alignment and location of PVC chamfer is important, so the chamfered concrete edge will have a good appearance after the form’s removal.  Figure 1 Figure 2 Chamfering the concrete edges done for many reasons such as aesthetics, some suggesting that the chamfering of concrete edges done for safety to reduce the damage of objects due to impact with sharp concrete edges. Actually, ...
Read more