CE151P-5 - Structural Loads PDF
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Jeremy Rifareal
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Summary
This document provides an overview of structural loads in buildings, covering gravity loads (dead load, live load, roof live load), lateral loads (earthquake load, wind load), other loads (fluid pressure, lateral soil pressure, ponding load, self-straining forces), and design codes. It also includes information about materials density and calculation examples.
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Internal Use Structural Loads in Buildings CE151P-5 – Building Systems Design Jeremy Rifareal, MSCE Instructor Internal Use Gravity Loads Dead Load Liv...
Internal Use Structural Loads in Buildings CE151P-5 – Building Systems Design Jeremy Rifareal, MSCE Instructor Internal Use Gravity Loads Dead Load Live Load Roof Live Load Internal Use Lateral Loads Earthquake Load Wind Load Internal Use Other Loads Fluid Pressure (with well defined magnitude) Lateral Soil Pressure Ponding Load Self-straining Forces and Effects Internal Use Design Codes / Standards Internal Use Dead Load Weight of all MATERIALS OF CONSTRUCTION incorporated into the building Internal Use GRAVITY 9.81 m/s^2 Roof Ceiling Plumbing Fixtures Dead Load Wall Floor Column Stair Internal Use Material Density Minimum material densities prescribed by NSCP 2015 Internal Use Dead Load per Unit Area Internal Use Dead Load due to Weight of Floor System Parameter Value Beam Width 300mm Beam Depth 400mm Column Width 400mm (square) Slab Thickness 100mm Concrete density 23.6 kN/m^3 Calculate the total floor weight. Internal Use Dead Load due to Weight of Walls Internal Use Live Loads Gravity loads that are not attached to the structure. Internal Use GRAVITY 9.81 m/s^2 Furniture Occupants (People) Live Load Internal Use Live Loads Minimum live loads prescribed by NSCP 2015 Internal Use Calculate Floor Live Loads Internal Use Live Load Reduction Internal Use Live Load Reduction Internal Use Roof Live Load Internal Use Earthquake - Earthquake is a weak to violent shaking of the ground produced by the sudden movement of rock materials below the Earth’s surface. Internal Use Earthquake - The earthquakes originate in tectonic plate boundary. - The point inside the earth where the earthquake started is called the hypocenter or focus. - The point on the surface of the earth directly above the focus is called the epicenter. Internal Use Earthquake - The earthquakes originate in tectonic plate boundary. - The point inside the earth where the earthquake started is called the hypocenter or focus. - The point on the surface of the earth directly above the focus is called the epicenter. Internal Use Earthquake - The earthquakes originate in tectonic plate boundary. - The point inside the earth where the earthquake started is called the hypocenter or focus. - The point on the surface of the earth directly above the focus is called the epicenter. Internal Use Earthquake Internal Use Earthquake Magnitude Magnitude is proportional to the energy released by an earthquake at the focus. It is calculated from earthquakes recorded by an instrument called seismograph. It is represented by Arabic Numbers (e.g. 4.8, 9.0). Internal Use Earthquake Intensity Intensity is the strength of an earthquake as perceived and felt by people in a certain locality. The intensity is generally higher near the epicenter. It is represented by Roman Numerals (e.g. II, IV, IX). PHIVOLCS Earthquake Intensity Scale (PEIS) Internal Use Earthquake Hazards Fault, Active Fault, and Ground Rupture Ground Shaking Earthquake-induced Landslides Liquefaction Tsunami Coastal Uplift or Subsidence https://www.phivolcs.dost.gov.ph/index.php/earthquake/earthquake-hazards Internal Use Past Earthquakes Earthquakes in the Philippines for the past 50 years with magnitude of at least 5.0. 1976 August 17 Mw8.1 Moro Gulf Earthquake Remembering the 1990 Luzon Earthquake that wreaked havoc in the Philippines Internal Use Earthquake Load Magnitude of code-based earthquake load depends on the following. Occupancy category (importance of structure) Distance to nearest seismic source Soil type Seismic zone Natural period of the structure Internal Use Occupancy Category (NSCP 2015) Internal Use Distance to Nearest Seismic Source Available tools by PHIVOLCS: Hazard Hunter FaultFinder Internal Use Soil Type Generally, soft or loose soil will result to higher earthquake loads than hard or dense soil. Internal Use Seismic Zone Internal Use Natural Period of the Structure The time required for the structure to complete one cycle of free vibration Internal Use Natural Period of the Structure (Example) Period, 𝑇 ≈ 1.17 s Internal Use Wind Load Magnitude of wind load depends on the following. Basic Wind Speed Exposure Category Topographic Effect Gust Effect Enclosure Classification Internal Use Basic Wind Speed The code provides the basic wind speed value for each occupancy category. Internal Use Exposure Category Internal Use Exposure Category B Internal Use Exposure Category D Internal Use Gust Effect Flexible structure – Potentially higher gust effect Rigid structure - Low gust effect © The Images Publishing Group Pty Ltd 2015 Internal Use Enclosure Category Open Building Image Source: Philippine Information Agency Internal Use Enclosure Category Enclosed Building PHOTO BY Facebook/G-Court Internal Use Wind Load Internal Use Fluid Pressure © Arch-Exist Internal Use Lateral Soil Pressure Internal Use Ponding Load Water accumulation due to deflection Internal Use Self-straining Forces and Effects The self-straining force covers temperature effects, creep, shrinkage, differential settlement and similar effects. Internal Use References National Structural Code of the Philippines, 7th Ed. (NSCP 2015) ASCE 7-22 – Minimum Design Loads and Associated Criteria for Buildings and Other Structures Department of Science and Technology – Philippine Institute of Volcanology and Seismology https://www.phivolcs.dost.gov.ph/index.php/earthquake/earthquake-hazards https://www.phivolcs.dost.gov.ph/index.php/earthquake/introduction-to- earthquake National Institute of Standards and Technology