Stopping Sight Distance for Horizontal Surfaces PDF

Stopping Sight Distance for Horizontal Surfaces By: Engr. Mark Joren Crisologo introduction Insufficient sight distance and limited forward visibility can adversely affect safety and increases the risk of acollision by reducing reaction and stopping distances. Adequate si...

Stopping Sight Distance for Horizontal Surfaces By: Engr. Mark Joren Crisologo introduction Insufficient sight distance and limited forward visibility can adversely affect safety and increases the risk of acollision by reducing reaction and stopping distances. Adequate sight distance provides drivers with sufficient time to identify and appropriately react to all elements of the road environment, including other road users and hazards. Sight distances are particularly important in areas where pedestrians and bicyclists are known to cross the road. Sight Distance It is the length of roadway visible to the driver. Stopping Sight Distance (SSD) It is the minimum sight distance available on a highway at any spot having sufficient length to enable the driver to stop a vehicle traveling at design speed, safely without collision with anyother obstruction. 4 Factors affecting Stopping Sight Distance (SSD) Total reaction time of driver Speed of Vehicle Efficienct of Brakes Frictional Resistance Between Road and Tire Gradient of Road 4 Total Reaction Time of Driver It is the time taken from the instant the object is visible to the driver to the instant the brake is effectively applied, it divided into two types Perception Reaction Time It is the time from the instant the object comes on the line of sight of the driver to the instant he realizes that the vehicle needs to be stopped. Brake Reaction Time The brake reaction depends on several factor including the skill of the driver, the type of the problems and various other environment factor. 4 PIEV Theory PIEV THEORY was proposed to provide detailed account of driver’s reaction. PIEV is the amount of time it takes a driver to react to a hazard. Total reaction time of driver is split into four parts: PERCEPTION Is the time required for the sensations received by the eyes or ears of the driver to be transmitted to the brain through the nervous system and spinal cord or it is the time required to perceive an object or situation. INTELLECTION Is the time required for the driver to understand the situation, it is also the time required for comparing the different thoughts. PIEV Theory PIEV THEORY was proposed to provide detailed account of driver’s reaction. PIEV is the amount of time it takes a driver to react to a hazard. Total reaction time of driver is split into four parts: Emotion Is the time elapsed during emotional sensational and other mental disturbance such as fear, anger or any other emotional feeling superstition. Volition Is the time taken by the driver for the final action such as brake application. REACTION DISTANCE The distance a vehicle travels from the moment a driver sees the object until the driver applies brakes. 𝑹. 𝑫 = 𝑽𝒕 BRAKING DISTANCE 𝑺𝑺𝑫 = 𝑹𝑫 + 𝑩𝑫 The distance a vehicle travels from the moment 𝑽𝟐 𝑺𝑺𝑫 = 𝑽𝒕 + the brakes are applied until the vehicle come to a 𝟐𝒈(𝒇+𝑮) complete stop. Where: V = velocity in m/sec 𝑽𝟐𝒊 −𝑽𝟐𝒇 𝑽𝟐 𝑩. 𝑫 = = t = Perception-Reaction Time 𝟐𝒈(𝒇+𝑮) 𝟐𝒈(𝒇+𝑮) F = coefficient of friction between tires and pavements G = average grade of roadway problem 1 The driver of a car traveling at a certain speed suddenly sees an obstruction ahead and traveled a distance of 58.3 m during the reaction time of 1.3 seconds. Determine the car’s speed of approach in kph. Answer: 161.45 kph problem 2 Determine the minimum stopping sight distance on a -3.5% grade for a design speed of 110 kph. Coefficient of friction between tires and pavement is 0.28. Driver’s reaction time (including perception time) is 2.5 sec Answer: 270.69 m problem 3 While descending a -7% grade at a speed of 90 kph, George notices a large object in the roadway ahead of him. Without thinking about any alternatives, George stabs his brakes and begins to slow down. Assuming that George is so paralyzed with fear that won’t engage in an avoidance maneuver, calculate the minimum distance at which George must have seen the object in order to avoid colliding with it. You can assume that the roadway surface is concrete and that the surface is wet (coefficient of friction is 0.29). You can also assume that George has a brake reaction time of 0.9 seconds because he is always alert on this stretch of the road. Answer: 167.30 m problem 4 Determine the minimum stopping sight distance on a -3.5% grade for a design speed of 110 kph. Coefficient of friction between tires and pavement is 0.28. Driver’s reaction time (including perception time) is 2.5 sec. Answer: 270.69 m problem 5 A car moving at 80 kph on a level road suddenly sees an obstruction 76 meters ahead. If the perception-reaction time is 0.5 sec. and the coefficient of friction between the tires and the pavement is 0.4, how far from the obstruction will it stop? Answer: 1.98 m problem 6 A driver traveling at 50 mph is 80 meters from a wall ahead. If the driver applies the brakes immediately after perception time of 2 seconds and begins slowing the vehicle at 10 m/sec^2 , find the distance from the stopping point to the wall. Answer: 10.32 m Homework Problem 1 A car traveling at 70 kph requires 48 m to stop after the brakes have been applied. What average coefficient of friction was developed between the tires and pavement. Problem 2 A vehicle moving at 80 kph up a 4% incline was stopped by applying brakes. If the coefficient of friction between the tires and the pavement is 0.30, compute the distance traveled by the vehicle before it stopped. Problem 3 Vehicles often travel city streets adjacent to parking lanes at 56 kph or faster. At his speed and setting detection through response-initiation time for an alert driver at 2 sec and f = 0.50, how far must the driver be away from a suddenly opened car door to avoid striking it?  MODULE III : URBAN TRANSPORTATION PLANNING By: Engr. Mark Joren Crisologo What is Transportation Planning? Transportation Planning is the preparation of transportation system such as highways and traffic facilities. Transportation planning is the first move before things are decided and needed to be done to ensure things are on the right path along the way to succeed. Why it is necessary for Urban Planning? Traffic Engineering is a relatively new field that has developed because traffic has become more of a problem recently. As more vehicles appeared on the roads, traffic jams made it harder for vehicles to move safely and efficiently. This led to more accidents, parking issues, and environmental pollution. To address these problems, it's important to focus on improving road design, traffic management, and related features like signals, signs, parking areas, bus and truck stations, and street lighting. Urbanization is the shift from rural areas to cities and towns. It shows how more people are moving from the countryside to urban areas. The level of urbanization indicates the percentage of people living in cities and towns, while the rate of urbanization measures how quickly this shift is happening. Why it is necessary for Urban Planning? Cities are areas with a lot of economic activity and complex systems, including transportation networks. Larger cities are more complex and can face more problems if not managed well. Urban productivity relies on efficient transport to move people and goods. Transport hubs like ports, airports, and railyards are important for connecting cities globally but also bring challenges. Some issues, like traffic congestion, have been around for a long time, while others, such as urban freight distribution and environmental impacts, are more recent.  Urban Transport Challenges 1. Traffic Congestion and Parking Difficulties Congestion is a common problem in large cities, especially those with over 1 million people. It often results from increased car use, which raises the demand for transport infrastructure that can't always keep up. Since cars are parked most of the time, the need for parking space has grown, causing issues, especially in central areas where parked cars take up a lot of space. By the 21st century, drivers face congestion three times more often than in the late 20th century.  Urban Transport Challenges 2. Longer Commuting People are spending more time commuting between their homes and workplaces, mainly because housing is cheaper farther from city centers where jobs are concentrated. This means they trade off time spent commuting for lower housing costs. Long commutes can lead to social issues like less time with family and friends and health problems like obesity. Commuting also reduces time available for other activities. However, information technology now enables people to work or perform other tasks while they travel.  Urban Transport Challenges 3. Public Transport Inadequacy Public transit systems often struggle with too many passengers during busy times and too few passengers during quieter times. At busy hours, the system can get overcrowded, making it uncomfortable for people. The challenge is finding the right balance: if the system is designed for busy times, it will be underused when it's quiet. If it's designed for average use, it can become crowded during busy times.  Urban Transport Challenges 4. Difficulties for Non-motorized Transport These issues arise from heavy traffic, which makes it hard for pedestrians and cyclists to move around, and from poor design that doesn’t consider their needs. On the other hand, adding bike paths can reduce space for cars and parking. If too much space is given to non-motorized transport compared to the actual demand, it can worsen congestion  Urban Transport Challenges 5. Loss of Public Space Most roads are owned by the public and open to everyone. Increased traffic has negatively affected public activities that used to take place on the streets, like markets, parades, and community events. These activities have either moved to shopping malls or disappeared. Heavy traffic disrupts social interactions and how people use street space. As traffic increases, people walk and cycle less, and social activities on the streets decline.  Urban Transport Challenges 6. High Infrastructure Maintenance Costs As cities deal with old transport systems, they face higher costs for maintaining and updating their infrastructure. Repairing and maintaining roads can cause traffic delays. Sometimes, cities delay maintenance to save money now, but this can lead to even bigger costs and problems later. The more roads and highways a city has, the more expensive it is to keep them in good shape. Public transit systems also need a well-planned maintenance strategy to handle these costs and avoid disruptions..  Urban Transport Challenges 7. Environmental Impacts and Energy Consumptions Pollution, including noise from traffic, harms both the quality of life and health in cities. Additionally, energy use for urban transport has risen sharply, increasing reliance on oil. As energy costs rise, there's more interest in finding efficient and sustainable transportation options, like public transit. Cities are under pressure to reduce carbon emissions from transportation, especially with the rise of alternative energy sources like electric vehicles.  Urban Transport Challenges 8. Accidents and Safety As traffic in urban areas increases, there are more accidents and fatalities, especially in developing countries. Accidents contribute significantly to congestion and delays. Higher traffic makes people feel less safe on the streets. Although information technology provides useful navigation and location details, it also causes distractions from portable devices, leading to more accidents for both drivers and pedestrians.  4 Stages of Transportation Planning The four main stages of the transportation planning process are: 1. Transportation survey, data collection and analysis 2. Use of transportation model 3. Future land use forecasts and alternative policy strategies 4. Policy evaluation  Transportation Safety The 4 E’s of Safety 1. Engineering – Engineers play a critical role in identifying and recommending solutions to address safety performance of the transportation infrastructure. 2. Enforcement – Law enforcement personnel generally are responsible for collecting crash data, traffic law enforcement, behavioral safety campaigns, and sharing information with transportation professionals. 3. Emergency Medical Services – This group includes first responders and paramedics, fire and rescue personnel, law enforcement, Department of Transportation (DOTr) personnel, and tow truck operators. 4. Education – Highway users are not always aware of the risks associated with their behaviors so proper knowledge and education of the uses of highway and safety along the way is highly recommended for all. Homework Among the different urban transportation challenges mentioned, choose two problems you think are the major problems in Metro Manila. Explain why and can you give what you think is the best solution for this? (Minimum of 500 words) Handwritten and please don’t use AI.  MODULE II : PHILIPPINE TRANSPORTATION SYSTEM By: Engr. Mark Joren Crisologo Philippine Transportation System Transport is crucial for the Philippine economy, connecting people and businesses across the islands. The country uses roads, water, air, and rail for transport. Water transport is important because the Philippines is made up of many islands, but roads are the most used, handling 98% of passenger traffic and 58% of cargo. There are about 215,000 kilometers of roads, 900 ports, and 90 airports in the country. However, the transport system still needs improvement due to insufficient funding. Better transport infrastructure is essential for boosting investment and economic growth. Government Sector Strategy Plan The main goal of the Philippine Development Plan 2011–2016 (PDP) is to achieve inclusive economic growth. This means creating steady growth that generates jobs, includes most people in economic and social activities, and reduces widespread poverty. The PDP identifies poor infrastructure and logistics as major barriers to investment and growth. It points out that insufficient public and private investment has led to inadequate infrastructure, which hampers economic expansion and affects the growing population. Furthermore, unequal access to basic infrastructure has acted as an obstacle to poverty reduction and prevented less fortunate from advancing throughout the country.  Five objectives of PDP for infrastructure development, including the transport sector: 1. Optimize resources and investments 2. Attract investments to infrastructure 3. Forster transparency and accountability in infrastructure development 4. Adapt to climate change and mitigate the impacts of natural disasters 5. Provide productive employment opportunities  URBAN TRANSPORT The Philippines is rapidly urbanizing, and by 2030, about 77% of the population will live in cities. There are 120 cities, including 16 in Metro Manila, which is the only metropolitan area in the country. Other major urban areas like Davao, Cebu, and Iloilo don't have formal metropolitan organizations. Most transport in these cities relies on roads, with Metro Manila being the exception. Public transport mainly includes privately owned jeepneys, taxis, tricycles, and pedicabs. In 2010, taxis made up 35% of the 1.9 million vehicles in Metro Manila, and half of the 6.6 million vehicles nationwide were motorcycles. Motorcycles are prone to accidents and contribute significantly to traffic congestion.  KEY SECTOR CHALLENGES The Philippines is made up of many islands, and as more people live in cities, it’s important to have good transportation between and within these islands. Efficient transportation helps boost the economy and makes it easier for businesses to operate. The goal is to connect the islands with a smooth transport network so that goods and services can move easily and cheaply. This improved connection is also crucial for the wider Southeast Asia region. By improving transportation, the Philippines can help stimulate trade, economic activity, and lower costs. Additionally, better urban transport systems on the busier islands are needed to keep up with the growing population and economic activity.  PUBLIC TRANSPORTATION Public transportation is generic term used to describe the family of transit services available to urban and rural residents. TRANSIT MODES: Mass Transit – characterized by fixed routes, published schedules, designated networks, and specified stops like buses, light rail, jeepneys etc. Paratransit – characterized by flexible and personalized service intended to replace conventional fixed-route, fixed-schedule mass-transit lines like taxi, angkas, etc. Ridesharing – characterized by two or more persons traveling together by prearrangement like uber, grab etc.  TRANSPORTATION ORGANIZATIONS These organizations/agencies were essential to the transportation system to function. Each has a special function to perform and serves to create a network of individuals who, working together, furnish the transportation systems and services that presently exist.  TRANSPORTATION ORGANIZATIONS 7 Categories of Organization in Transportation 1. Private Companies – available for hire companies (Transport companies) 2. Regulatory Agencies – monitors the transport companies (like LTFRB) 3. Federal Agencies - legislation for national level (like DOTr) 4. State and Local Agencies and Authorities – planning, design and construction (like DPWH) 5. Trade Associations – representatives for marketing and business (like Petroleum companies, Automobile companies) 6. Professional Societies – planning consultants (like AASHTO) 7. User of Transport Services – transportation consumer (like CUP) END OF MODULE II  MODULE I : INTRODUCTION TO TRANSPORTATION ENGINEERING By: Engr. Mark Joren Crisologo What is Transportation Engineering ? Transportation Engineering is a branch of Civil Engineering that is involved in the planning, design, operation, and maintenance of safe and efficient transportation systems. Transportation engineers are required to possess a long-term vision of the future. They must remain steadfast, patient, and persistent in guiding a transportation project to completion. The transportation engineer works in an environment where change is gradual and sometimes imperceptible. Transportation ensures time and place utility. It results in the movement of goods from one place to another place thus making the product available through the customer at the right time. To develop the economy of certain nation, good transportation is one of the key elements. Without good transportation, a nation or region cannot achieve the maximum use of its natural resources or the maximum productivity of its people. Progress in transportation is not without its costs, both in human lives and environmental damage, and it is the responsibility of the transportation engineer working with the public to develop high- quality transportation consistent with available funds and social policy and to minimize damage.  Different Modes of Transportation 1. Road Transportation A road is an identifiable route way or path between two or more places. This mode of transport helps to transfer the goods from one place to another place by road through various methods like auto, buses, trucks, cargos, and other suitable factors. In road transport, the chances of an accident are very high and it is also very risky.  Different Modes of Transportation 2. Railway Transportation It is preferred due to high speed. Invariance to road transport, where vehicles run on a flat road or surface, Rail vehicles are directionally managed by the rail tracks on which they run. Within the confines of the railway system, the rail vehicle is not influenced by traffic, points of diversion, and switch offs between modes. This makes the rail the most dependable mode for making long hauls across land with minimal damage. Trains commonly carry bulk cargo items such as coal, corn, iron, ore, and wheat, items that would be uneconomical to ship by truck.  Different Modes of Transportation 3. Maritime Transportation It involves the movement of goods through oceans and seas. Cargo ships travel on almost every major body of water and have capacity to transport the highest volume of freight of any mode of transportation at the lowest cost. The greatest disadvantage of maritime cargo ships is the speed at which they operate. By far, maritime is the slowest mode of transportation. Additionally, the carbon emissions produced by one cargo ship are equivalent to the emissions produced by 50 million cars.  Different Modes of Transportation 4. Air Transportation Airplanes are becoming increasingly important in domestic and international trade. As air travel has become increasingly advanced and dependable, more companies are trusting airplanes with high value freight and goods. The increasing popularity of flight as a preferred way to travel also makes shipping by air more convenient as shipments regularly piggyback on passenger planes, further making air an economic way to transport goods.  Different Modes of Transportation 5. Pipelines Pipeline shipping is not a formal mode of transportation in the traditional sense. However, it is important to acknowledge for its importance in the current fossil fuel market. Pipe-lines are the specialized means of transportation designed to move the items like crude-oil, petroleum, chemicals, coal, lime-stone, iron- ore, copper concentrates and gas.  Different Modes of Transportation 6. Cable Transportation Cable transportation is a broad class of transport modes that have cables. They transport passengers and goods, often in vehicles called cable cars. The cable may be driven or passive, and items may be moved by pulling, sliding, sailing or by drives with object moved on cableways. The use of pulleys and balancing of loads moving up and down are common elements of cable transport. They are often used in mountainous area where cable haulage can overcome large differences in elevation.  Different Modes of Transportation 7. Space Transportation Space transportation, or sometimes called Spaceflight, is an application of astronautics to fly objects, usually spacecraft, into or through outer space, either with or without humans on board. Most spaceflight is uncrewed and conducted mainly with spacecraft such as satellites in orbit around Earth, but also includes space probes for flights beyond Earth orbit.