Horizontal Curve and Road Design Problems

Problem 1: Circular Curve Design

A simple circular curve exists with a degree of curve D=12 and e=0.08. A structure is proposed on land on the inside of the curve. Assume the road is on level grade. Determine:

  1. The radius of the curve.
  2. The current maximum safe speed on the curve.
  3. The maximum distance allowable between the proposed structure and the centerline of the curve, such that the current maximum safe speed of the curve would not be reduced. Perception-reaction time is 2.5 seconds and fs=0.16

Solution:

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Cargo Terminals: Types, Operations, and Handling Equipment

Cargo Terminal Types and Operations

General Cargo Terminals

Classification:

  • Conventional: These are older terminals, initially not designed for unitized cargo. They feature a simple layout and generally don’t require extensive areas for cargo handling. Dimensions and installations depend on the cargo type, with open storage areas, light storage facilities, silos, and horizontal storage.

How They Operate

For loading and discharging, they use mobile shore cranes with a lifting capacity of 20-30 metric

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Road Surface Treatments: Bituminous Layers and Irrigation

Road Surface Treatments Explained

Surface treatments involve applying a thin bituminous layer (1-4 cm). Their primary purposes are:

  • To provide specific surface features like texture and waterproofing.
  • To improve adhesion.

However, they generally do not increase the structural strength capacity or improve the evenness of the underlying pavement structure.

t6

Gravel-Free Irrigation Methods

Black Irrigation

This involves surface irrigation on low-intensity traffic routes. It provides waterproofing, aging protection,

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Concrete Surface Repair: Strategies, Materials, and Techniques

Module 4

Concrete Surface Repair Strategies

The repair strategy is built around an existing losing stock position and is constructed by purchasing one call option and selling two call options for every 100 shares of stock owned. We use repair strategies when there is a communication breakdown. We can also use repair strategies to prevent a communication breakdown. For example, a miscommunication, a word or phrase that was not clear, not being able to hear the speaker, not understanding the speaker,

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Urban Street Design Elements: Medians, Parking, and Lanes

Medians and Central Reservations

The median or central reservation is defined as the longitudinal separation between carriageways on very wide streets when they are not passable. Its installation has advantages and disadvantages.

Advantages:

  • Increased safety measures.
  • Allows for future expansion of roadways.
  • Provides visual separation (rupture).
  • Serves as a pedestrian refuge.
  • Acts as a barrier to nuisance traffic.

Disadvantages:

  • Decreases the useful section of the road.
  • Can sometimes be a barrier to the movement
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Transportation Engineering: Key Concepts and Applications

Transportation Engineering: Key Concepts

In transportation engineering, the Level of Service (LOS) is a framework used to evaluate the quality of traffic flow on transportation systems, such as roads, highways, and intersections. It is defined in the Highway Capacity Manual (HCM) and serves as a critical tool for planning, designing, and managing transportation infrastructure.

Level of Service (LOS) Grades

  • LOS A:
    • Free-flow conditions with no congestion.
    • High speeds, minimal delays, and full freedom to
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