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91-496: The Kahlert Mercantile Store is a two-story wood- frame building with a 25-by-82-foot (7.6 by 25 m) footprint. It has the squared-off false front typical of 19th-century rural and frontier towns. However the second floor rises a full story to accommodate the meeting hall, whereas most such buildings had a truncated upper floor. The Kahlert Store lacks any basement. The building is covered in clapboard siding broken by two-over-two sash windows . A balcony once projected from

182-538: A (scaled) model of the structure on a shake-table that simulates the earth shaking and observing its behavior. Such kinds of experiments were first performed more than a century ago. Only recently has it become possible to perform 1:1 scale testing on full structures. Due to the costly nature of such tests, they tend to be used mainly for understanding the seismic behavior of structures, validating models and verifying analysis methods. Thus, once properly validated, computational models and numerical procedures tend to carry

273-490: A Dimensional number two-by-four to 5 cm by 30 cm (two-by-twelve inches) at the cross-section, and lengths ranging from 2.5 metres (8.2 ft) for walls to 7 metres (23 ft) or more for joists and rafters. Recently, architects have begun experimenting with pre-cut modular aluminum framing to reduce on-site construction costs. Wall panels built of studs are interrupted by sections that provide rough openings for doors and windows . Openings are typically spanned by

364-442: A base of a building, their energy flow density, due to reflections, reduces dramatically: usually, up to 90%. However, the remaining portions of the incident waves during a major earthquake still bear a huge devastating potential. After the seismic waves enter a superstructure , there are a number of ways to control them in order to soothe their damaging effect and improve the building's seismic performance, for instance: Devices of

455-419: A bottom plate or foundation sill and in turn support the top plate. Studs usually consist of 1 + 1 ⁄ 2 -by- 3 + 1 ⁄ 2 -inch (38 mm × 89 mm) or 1 + 1 ⁄ 2 -by- 5 + 1 ⁄ 2 -inch (38 mm × 140 mm) lumber and are commonly spaced at 16 inches (410 mm) on center. This spacing may be changed to 12 or 24 inches (300 or 610 mm) on center depending on

546-445: A bottom plate which is secured to the structure of a floor, and one, or more often two top plates that tie walls together and provide a bearing for structures above the wall. Wood or steel floor frames usually include a rim joist around the perimeter of a system of floor joists, and often include bridging material near the center of a span to prevent lateral buckling of the spanning members. In two-story construction, openings are left in

637-850: A floor and as a support for the structure. Other light-frame buildings are built over a crawlspace or a basement , with wood or steel joists used to span between foundation walls, usually constructed of poured concrete or concrete blocks . Engineered components are commonly used to form floor, ceiling and roof structures in place of solid wood. I-joists (closed-web trusses) are often made from laminated woods, most often chipped poplar wood, in panels as thin as 1 cm (0.39 in), glued between horizontally laminated members of less than 4 cm by 4 cm ( two-by-twos ), to span distances of as much as 9 m (30 ft). Open web trussed joists and rafters are often formed of 4 cm by 9 cm ( two-by-four ) wood members to provide support for floors, roofing systems and ceiling finishes. Platform framing

728-556: A header or lintel that bears the weight of the structure above the opening. Headers are usually built to rest on trimmers , also called jacks. Areas around windows are defined by a sill beneath the window, and cripples, which are shorter studs that span the area from the bottom plate to the sill and sometimes from the top of the window to a header, or from a header to a top plate. Diagonal bracings made of wood or steel provide shear (horizontal strength) as do panels of sheeting nailed to studs, sills and headers. Wall sections usually include

819-429: A heavy damping . It was invented by Bill Robinson , a New Zealander. Heavy damping mechanism incorporated in vibration control technologies and, particularly, in base isolation devices, is often considered a valuable source of suppressing vibrations thus enhancing a building's seismic performance. However, for the rather pliant systems such as base isolated structures, with a relatively low bearing stiffness but with

910-600: A high damping, the so-called "damping force" may turn out the main pushing force at a strong earthquake. The video shows a Lead Rubber Bearing being tested at the UCSD Caltrans-SRMD facility. The bearing is made of rubber with a lead core. It was a uniaxial test in which the bearing was also under a full structure load. Many buildings and bridges, both in New Zealand and elsewhere, are protected with lead dampers and lead and rubber bearings. Te Papa Tongarewa ,

1001-504: A major earthquake. A properly engineered structure does not necessarily have to be extremely strong or expensive. It has to be properly designed to withstand the seismic effects while sustaining an acceptable level of damage. Earthquake engineering is a scientific field concerned with protecting society, the natural environment, and the man-made environment from earthquakes by limiting the seismic risk to socio-economically acceptable levels. Traditionally, it has been narrowly defined as

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1092-401: A nailing base for all covering material and support the upper floor platforms, which provide the lateral strength along a wall. The platforms may be the boxed structure of a ceiling and roof, or the ceiling and floor joists of the story above. In the building trades, the technique is variously referred to as stick framing , stick and platform , or stick and box , as the sticks (studs) give

1183-485: A real event. Sometimes earthquake simulation is understood as a re-creation of local effects of a strong earth shaking. Theoretical or experimental evaluation of anticipated seismic performance mostly requires a structure simulation which is based on the concept of structural likeness or similarity. Similarity is some degree of analogy or resemblance between two or more objects. The notion of similarity rests either on exact or approximate repetitions of patterns in

1274-408: A ridge. Valleys are formed when two sloping roof sections drain toward each other. Dormers are small areas in which vertical walls interrupt a roof line, and which are topped off by slopes at usually right angles to a main roof section. Gables are formed when a length-wise section of sloping roof ends to form a triangular wall section. Clerestories are formed by an interruption along the slope of

1365-649: A roof is called an A-frame . In North America, roofs are often covered with shingles made of asphalt, fiberglass and small gravel coating, but a wide range of materials are used. Molten tar is often used to waterproof flatter roofs, but newer materials include rubber and synthetic materials. Steel panels are popular roof coverings in some areas, preferred for their durability. Slate or tile roofs offer more historic coverings for light-frame roofs. Light-frame methods allow easy construction of unique roof designs; hip roofs, for example, slope toward walls on all sides and are joined at hip rafters that span from corners to

1456-550: A roof where a short vertical wall connects it to another roof section. Flat roofs, which usually include at least a nominal slope to shed water, are often surrounded by parapet walls with openings (called scuppers ) to allow water to drain out. Sloping crickets are built into roofs to direct water away from areas of poor drainage, such as behind a chimney at the bottom of a sloping section. Light-frame buildings in areas with shallow or nonexistent frost depths are often erected on monolithic concrete-slab foundations that serve both as

1547-484: A separate unit or platform. The use of factory-made walls and floors has shown an increase in popularity due to the time-saving and cost-efficiency. ( Pre-fabrication ) Walls are made usually in facilities and then shipped to the different job sites. This process of framing has improved the speed of framing on site moving the framing of buildings to speed up. Framed construction was rarely used in Scandinavia before

1638-417: A simulation tool development area, a curated central data repository, animated presentations, user support, telepresence, mechanism for uploading and sharing resources, and statistics about users and usage patterns. This cyberinfrastructure allows researchers to: securely store, organize and share data within a standardized framework in a central location; remotely observe and participate in experiments through

1729-583: A structural building that goes diagonally across a wall is called a T-bar. It stops the walls from collapsing in gusty winds. Pressure-treated wood (Green Treated wood) is a type of wood that is used when a bottom plate is exposed to outside moisture, while even when in contact with concrete. Roofs are usually built to provide a sloping surface intended to shed rain or snow, with slopes ranging from 1:15 (less than an inch per linear foot of horizontal span), to steep slopes of more than 2:1. A light-frame structure built mostly inside sloping walls which also serve as

1820-399: A structure's expected seismic performance, some researchers prefer to deal with so called "real time-histories" though the last cannot be "real" for a hypothetical earthquake specified by either a building code or by some particular research requirements. Therefore, there is a strong incentive to engage an earthquake simulation which is the seismic input that possesses only essential features of

1911-532: A sturdy, light skeleton. Builders were reluctant to adopt the new technology; however, by the 1880s, some form of 2×4 framing was standard. Alternatively, a precursor to the balloon frame may have been used by the French in Missouri as much as 31 years earlier. Although lumber was plentiful in 19th-century America, skilled labor was not. The advent of cheap machine-made nails, along with water-powered sawmills in

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2002-513: A wide variety of architectural styles. Modern light-frame structures usually gain strength from rigid panels ( plywood and other plywood-like composites such as oriented strand board (OSB) used to form all or part of wall sections), but until recently carpenters employed various forms of diagonal bracing to stabilize walls. Diagonal bracing remains a vital interior part of many roof systems, and in-wall wind braces are required by building codes in many municipalities or by individual state laws in

2093-468: Is kinematic equivalence when, in the case of earthquake engineering, time-histories of each story lateral displacements of the model and its prototype would be the same. Seismic vibration control is a set of technical means aimed to mitigate seismic impacts in building and non-building structures. All seismic vibration control devices may be classified as passive , active or hybrid where: When ground seismic waves reach up and start to penetrate

2184-468: Is a highly seismic land; for centuries the dry-stone construction proved to be more earthquake-resistant than using mortar. People of Inca civilization were masters of the polished 'dry-stone walls', called ashlar , where blocks of stone were cut to fit together tightly without any mortar . The Incas were among the best stonemasons the world has ever seen and many junctions in their masonry were so perfect that even blades of grass could not fit between

2275-768: Is a leader in dissemination of earthquake engineering research related information both in the U.S. and globally. A definitive list of earthquake engineering research related shaking tables around the world may be found in Experimental Facilities for Earthquake Engineering Simulation Worldwide. The most prominent of them is now E-Defense Shake Table in Japan . NSF also supports the George E. Brown Jr. Network for Earthquake Engineering Simulation The NSF Hazard Mitigation and Structural Engineering program (HMSE) supports research on new technologies for improving

2366-412: Is a relatively recent development. In general, seismic structural analysis is based on the methods of structural dynamics . For decades, the most prominent instrument of seismic analysis has been the earthquake response spectrum method which also contributed to the proposed building code's concept of today. However, such methods are good only for linear elastic systems, being largely unable to model

2457-408: Is also likely that, by radically reducing construction costs, balloon framing improved the shelter options of poorer North Americans. However, balloon framing did require very long studs, and as tall trees were exhausted in the 1920s, platform framing became prevalent. Balloon framing presents challenges in firefighting, since many older balloon-framed buildings lack firestops or fire blocking in

2548-580: Is an early form of light framing developed from the heavier timber framing which preceded it. It is defined by the continued use of girts, corner posts, and braces. The pieces are mortised, tenoned, and pegged with the studs nailed to the girts and sills. Due to the early introduction of sawmills (as early as 1635 in New Hampshire), as early as 1637 timber frames in the northeastern English colonies in North America made use of light studs between

2639-650: Is at the floor lines. The balloon wall studs extend from the sill of the first story all the way to the top plate or end rafter of the second story. The platform-framed wall, on the other hand, is independent for each floor. Light-frame materials are most often wood or rectangular steel, tubes or C-channels. Wood pieces are typically connected with nail fasteners, nails, or screws; steel pieces are connected with pan-head framing screws, or nuts and bolts. Preferred species for linear structural members are softwoods such as spruce, pine and fir. Light frame material dimensions range from 38 by 89 mm (1.5 by 3.5 in); i.e.,

2730-466: Is commonly referred to as dead wood or backing. Wall framing in house construction includes the vertical and horizontal members of exterior walls and interior partitions. These members, referred to as studs, wall plates and lintels, serve as a nailing base for all covering material and support the upper floors, ceiling and roof. Exterior wall studs are the vertical members to which the wall sheathing and cladding are attached. They are supported on

2821-426: Is conducted in order to evaluate the seismic performance of buildings. Performance evaluations are generally carried out by using nonlinear static pushover analysis or nonlinear time-history analysis. In such analyses, it is essential to achieve accurate non-linear modeling of structural components such as beams, columns, beam-column joints, shear walls etc. Thus, experimental results play an important role in determining

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2912-464: Is expected at a given location on the Earth's surface is estimated by engineering seismology . It is related to the seismic hazard of the location. Earthquake or seismic performance defines a structure's ability to sustain its main functions, such as its safety and serviceability , at and after a particular earthquake exposure. A structure is normally considered safe if it does not endanger

3003-449: Is generally called mass wall construction, where horizontal layers of stacked materials such as log building , masonry , rammed earth , adobe , etc. are used without framing. Building framing is divided into two broad categories, heavy-frame construction (heavy framing) if the vertical supports are few and heavy such as in timber framing , pole building framing , or steel framing ; or light-frame construction (light-framing) if

3094-420: Is generally used at exterior corners and intersections to secure a good tie between adjoining walls. It provides nailing support for interior finishes and exterior sheathing. Corners and intersections, however, must be framed with at least two studs. Nailing support for the edges of the ceiling is required at the junction of the wall and ceiling where partitions run parallel to the ceiling joists. This material

3185-439: Is not a problem and there is no required maintenance. They have a rectangular hysteretic loop and as long as the building is sufficiently elastic they tend to settle back to their original positions after an earthquake. Metallic yielding dampers, as the name implies, yield in order to absorb the earthquake's energy. This type of damper absorbs a large amount of energy however they must be replaced after an earthquake and may prevent

3276-708: Is not certain who introduced balloon framing in the United States. However, the first building using balloon framing was possibly a warehouse constructed in 1832 in Chicago , Illinois, by George Washington Snow or Augustine Deodat Taylor. Both men arrived in Chicago from New England, where the use of light framing timber was already common. Architectural critic Sigfried Giedion cited Chicago architect John M. Van Osdel 's 1880s attribution, as well as A. T. Andreas' 1885 History of Chicago, to credit Snow as 'inventor of

3367-560: The University of Texas, Austin . The equipment sites (labs) and a central data repository are connected to the global earthquake engineering community via the NEEShub website. The NEES website is powered by HUBzero software developed at Purdue University for nanoHUB specifically to help the scientific community share resources and collaborate. The cyberinfrastructure, connected via Internet2 , provides interactive simulation tools,

3458-524: The load and the limitations imposed by the type and thickness of the wall covering used. Wider 1 + 1 ⁄ 2 -by- 5 + 1 ⁄ 2 -inch studs may be used to provide space for more insulation . Insulation beyond that which can be accommodated within a 3 + 1 ⁄ 2 -inch stud space can also be provided by other means, such as rigid or semi-rigid insulation or batts between 1 + 1 ⁄ 2 -by- 1 + 1 ⁄ 2 -inch horizontal furring strips , or rigid or semi-rigid insulation sheathing to

3549-399: The resonance frequency oscillations of the structures by means of some sort of spring mechanism. The Taipei 101 skyscraper needs to withstand typhoon winds and earthquake tremors common in this area of Asia/Pacific. For this purpose, a steel pendulum weighing 660 metric tonnes that serves as a tuned mass damper was designed and installed atop the structure. Suspended from the 92nd to

3640-415: The social sciences , especially sociology , political science , economics , and finance . The main objectives of earthquake engineering are: Seismic loading means application of an earthquake-generated excitation on a structure (or geo-structure). It happens at contact surfaces of a structure either with the ground, with adjacent structures, or with gravity waves from tsunami . The loading that

3731-610: The 20th century because of the abundant availability of wood, an abundance of cheap labour, and the superiority of the thermal insulation of logs. Hence timber framing was used first for unheated buildings such as farm buildings, outbuildings and summer villas, but for houses only with the development of wall insulation. Wall framing in house construction includes the vertical and horizontal members of exterior walls and interior partitions, both of bearing walls and non-bearing walls. These stick members , referred to as studs , wall plates and lintels (sometimes called headers ), serve as

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3822-400: The 88th floor, the pendulum sways to decrease resonant amplifications of lateral displacements in the building caused by earthquakes and strong gusts . A hysteretic damper is intended to provide better and more reliable seismic performance than that of a conventional structure by increasing the dissipation of seismic input energy. There are five major groups of hysteretic dampers used for

3913-580: The Sauk Center and Northern Railway—a subsidiary of the St. Paul, Minneapolis and Manitoba Railway —built a rail line nearby. Although mostly intended to access railroad-owned timber land, the rail line sparked the establishment of several towns along its route, including Browerville. Although a small village had been coalescing in Hartford Township, most of its business owners quickly relocated to

4004-406: The United States. Special framed shear walls are becoming more common to help buildings meet the requirements of earthquake engineering and wind engineering . Historically, people fitted naturally shaped wooden poles together as framework and then began using joints to connect the timbers, a method today called traditional timber framing or log framing . In the United States, timber framing

4095-525: The balloon frame method'. In 1833, Taylor constructed the first Catholic church in Chicago, St. Mary's, using the balloon framing method; this building was moved and rehabbed multiple times before burning in the Great Chicago Fire . In the 1830s, Hoosier Solon Robinson published articles about a revolutionary new framing system, called "balloon framing" by later builders. Robinson's system called for standard 2×4 lumber, nailed together to form

4186-474: The base of the building which should substantially decouple a superstructure from its substructure resting on a shaking ground. The first evidence of earthquake protection by using the principle of base isolation was discovered in Pasargadae , a city in ancient Persia, now Iran, and dates back to the 6th century BCE. Below, there are some samples of seismic vibration control technologies of today. Peru

4277-535: The behaviour and response of structural systems subject to earthquake hazards; fundamental research on safety and reliability of constructed systems; innovative developments in analysis and model based simulation of structural behaviour and response including soil-structure interaction; design concepts that improve structure performance and flexibility; and application of new control techniques for structural systems. (NEES) that advances knowledge discovery and innovation for earthquakes and tsunami loss reduction of

4368-409: The bottom plates nailed through the subfloor to the floor framing members. The braces should have their larger dimension on the vertical and should permit adjustment of the vertical position of the wall. Once the assembled sections are plumbed, they are nailed together at the corners and intersections. A strip of polyethylene is often placed between the interior walls and the exterior wall, and above

4459-399: The building from settling back to its original position. Viscoelastic dampers are useful in that they can be used for both wind and seismic applications, they are usually limited to small displacements. There is some concern as to the reliability of the technology as some brands have been banned from use in buildings in the United States. Base isolation seeks to prevent the kinetic energy of

4550-428: The compared items. In general, a building model is said to have similarity with the real object if the two share geometric similarity , kinematic similarity and dynamic similarity . The most vivid and effective type of similarity is the kinematic one. Kinematic similarity exists when the paths and velocities of moving particles of a model and its prototype are similar. The ultimate level of kinematic similarity

4641-506: The early 19th century made balloon framing highly attractive, because it did not require highly skilled carpenters, as did the dovetail joints , mortises and tenons required by post-and-beam construction . For the first time, any farmer could build his own buildings without a time-consuming learning curve. It has been said that balloon framing populated the western United States and the western provinces of Canada. Without it, western boomtowns certainly could not have blossomed overnight. It

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4732-405: The earthquake from being transferred into elastic energy in the building. These technologies do so by isolating the structure from the ground, thus enabling them to move somewhat independently. The degree to which the energy is transferred into the structure and how the energy is dissipated will vary depending on the technology used. Lead rubber bearing or LRB is a type of base isolation employing

4823-546: The first machines developed in the late 1700s in Massachusetts. Jacob Perkins of Newburyport, Massachusetts , invented a machine which could produce 10,000 nails a day. Three-decker buildings in New England were commonly constructed with this form, which is noted on period building permits as "mortised frame." Its use survived into the 1940s in the northeastern United States, when it was gradually replaced by

4914-437: The first top plate of interior walls before the second top plate is applied to attain continuity of the air barrier when polyethylene is serving this function. A second top plate, with joints offset at least one stud space away from the joints in the plate beneath, is then added. This second top plate usually laps the first plate at the corners and partition intersections and, when nailed in place, provides an additional tie to

5005-848: The floor system for a stairwell, in which stair risers and treads are most often attached to squared faces cut into sloping stair stringers. Interior wall coverings in light-frame construction typically include wallboard , lath and plaster or decorative wood paneling . Exterior finishes for walls and ceilings often include plywood or composite sheathing, brick or stone veneers , and various stucco finishes. Cavities between studs, usually placed 40–60 cm (16–24 in) apart, are usually filled with insulation materials, such as fiberglass batting, or cellulose filling sometimes made of recycled newsprint treated with boron additives for fire prevention and vermin control. In natural building , straw bales , cob and adobe may be used for both exterior and interior walls. The part of

5096-483: The framed walls. Where the second top plate does not lap the plate immediately underneath at corner and partition intersections, these may be tied with 0.036 in (0.91 mm) galvanized steel plates at least 3 in (76 mm) wide and 6 in (150 mm) long, nailed with at least three 2 + 1 ⁄ 2  in (64 mm) nails to each wall. Braced frame construction , also known as full frame, half frame, New England braced frame, combination frame,

5187-510: The front façade. It was removed around 1910, likely to accommodate improvements to the adjacent street or sidewalk. The only other major exterior alteration is the addition of a sliding garage door near the rear of the north wall. The Kahlert Mercantile Store was established by brothers William and Ferdinand Kahlert. They were early settlers of Todd County who arrived in 1870, initially homesteading in Hartford Township . In 1882

5278-417: The heavier corners. Norman Isham wrote, "sometimes the frame was covered with vertical boarding applied to the sills, plates, and girts without any intermediate framing, but in a greater number of houses the spaces between the heavier timbers are filled with lighter vertical sticks called studs." The growth of a nail-making industry in the early 19th century made the frame even faster to assemble, with some of

5369-546: The last kind, abbreviated correspondingly as TMD for the tuned ( passive ), as AMD for the active , and as HMD for the hybrid mass dampers , have been studied and installed in high-rise buildings , predominantly in Japan, for a quarter of a century. However, there is quite another approach: partial suppression of the seismic energy flow into the superstructure known as seismic or base isolation . For this, some pads are inserted into or under all major load-carrying elements in

5460-454: The light of new findings, and practical application of the developed theories. The National Science Foundation (NSF) is the main United States government agency that supports fundamental research and education in all fields of earthquake engineering. In particular, it focuses on experimental, analytical and computational research on design and performance enhancement of structural systems. The Earthquake Engineering Research Institute (EERI)

5551-440: The lives and well-being of those in or around it by partially or completely collapsing. A structure may be considered serviceable if it is able to fulfill its operational functions for which it was designed. Basic concepts of the earthquake engineering, implemented in the major building codes, assume that a building should survive a rare, very severe earthquake by sustaining significant damage but without globally collapsing. On

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5642-401: The loads supported and the type and thickness of the wall finish used. Partitions can be built with 1 + 1 ⁄ 2  in ×  2 + 1 ⁄ 2  in (38 mm × 64 mm) or 1 + 1 ⁄ 2  in ×  3 + 1 ⁄ 2  in (38 mm × 89 mm) studs spaced at 16 or 24 in (410 or 610 mm) on center depending on the type and thickness of

5733-410: The major burden for the seismic performance assessment of structures. Seismic performance assessment or seismic structural analysis is a powerful tool of earthquake engineering which utilizes detailed modelling of the structure together with methods of structural analysis to gain a better understanding of seismic performance of building and non-building structures . The technique as a formal concept

5824-600: The means for collaboration and discovery to improve the seismic design and performance of civil and mechanical infrastructure systems. The very first earthquake simulations were performed by statically applying some horizontal inertia forces based on scaled peak ground accelerations to a mathematical model of a building. With the further development of computational technologies, static approaches began to give way to dynamic ones. Dynamic experiments on building and non-building structures may be physical, like shake-table testing , or virtual ones. In both cases, to verify

5915-414: The modeling parameters of individual components, especially those that are subject to significant non-linear deformations. The individual components are then assembled to create a full non-linear model of the structure. Thus created models are analyzed to evaluate the performance of buildings. The capabilities of the structural analysis software are a major consideration in the above process as they restrict

6006-497: The most commonly used hysteretic damper. Friction dampers tend to be available in two major types, linear and rotational and dissipate energy by heat. The damper operates on the principle of a coulomb damper . Depending on the design, friction dampers can experience stick-slip phenomenon and Cold welding . The main disadvantage being that friction surfaces can wear over time and for this reason they are not recommended for dissipating wind loads. When used in seismic applications wear

6097-876: The nation's civil infrastructure and new experimental simulation techniques and instrumentation. The NEES network features 14 geographically distributed, shared-use laboratories that support several types of experimental work: geotechnical centrifuge research, shake-table tests, large-scale structural testing, tsunami wave basin experiments, and field site research. Participating universities include: Cornell University ; Lehigh University ; Oregon State University ; Rensselaer Polytechnic Institute ; University at Buffalo , State University of New York ; University of California, Berkeley ; University of California, Davis ; University of California, Los Angeles ; University of California, San Diego ; University of California, Santa Barbara ; University of Illinois, Urbana-Champaign ; University of Minnesota ; University of Nevada, Reno ; and

6188-510: The need to scaffold , and again increasing speed and cutting manpower needs and expenses. Some types of exterior sheathing, such as asphalt-impregnated fiberboard , plywood , oriented strand board and waferboard , will provide adequate bracing to resist lateral loads and keep the wall square (construction codes in most jurisdictions require a stiff plywood sheathing). Others, such as rigid glass-fiber, asphalt-coated fiberboard, polystyrene or polyurethane board, will not. In this latter case,

6279-657: The new trackside town, and the Kahlert brothers followed suit in 1883. Their building, at the corner of Main Street and 6th Street, used the same false-front style as most of the other early construction in Browerville. They operated a general store and grocery out of the ground floor. Despite competition from several similar stores in town, the Kahlerts prospered and even expanded into an adjacent building by 1900. Over

6370-410: The open framing cavities, and a fire can spread vertically in a short time. Since the floor framing and wall framing cavities interconnect, fire can rapidly spread throughout the structure. Many balloon-framed buildings predate the introduction of building codes that mandate fire blocking, and a fire can spread from basement to attic in minutes. The main difference between platform and balloon framing

6461-460: The opening may be bridged with a single piece of 1 + 1 ⁄ 2  in (38 mm) lumber the same width as the studs. These members provide a nailing support for wall finish, door frames and trim . Lintels (or, headers) are the horizontal members placed over window, door and other openings to carry loads to the adjoining studs. Lintels are usually constructed of two pieces of 2 in (nominal) (38 mm) lumber separated with spacers to

6552-446: The other hand, it should remain operational for more frequent, but less severe seismic events. Engineers need to know the quantified level of the actual or anticipated seismic performance associated with the direct damage to an individual building subject to a specified ground shaking. Such an assessment may be performed either experimentally or analytically. Experimental evaluations are expensive tests that are typically done by placing

6643-637: The outside of the studs. The studs are attached to horizontal top and bottom wall plates of 1 + 1 ⁄ 2 -inch lumber that are the same width as the studs. Interior partitions supporting floor , ceiling or roof loads are called loadbearing walls; others are called non-loadbearing or simply partitions. Interior loadbearing walls are framed in the same way as exterior walls. Studs are usually 1 + 1 ⁄ 2  in ×  3 + 1 ⁄ 2  in (38 mm × 89 mm) lumber spaced at 16 in (410 mm) on center. This spacing may be changed to 12 or 24 in (300 or 610 mm) depending on

6734-529: The platform frame. Balloon framing is a method of wood construction used primarily in areas rich in softwood forests such as Scandinavia , Canada , the United States up until the mid-1950s, and around Thetford Forest in Norfolk, England . The name comes from a French Missouri type of construction, maison en boulin , boulin being a French term for a horizontal scaffolding support. It

6825-411: The platforms and walls above the level of its component headers and joists. In some countries, framing lumber is subject to regulated standards that require a grade-stamp, and a moisture content not exceeding 19%. There are four historically common methods of framing a house. Wall sheathing, usually a plywood or other laminate, is usually applied to the framing prior to erection, thus eliminating

6916-530: The possible component models, the analysis methods available and, most importantly, the numerical robustness. The latter becomes a major consideration for structures that venture into the non-linear range and approach global or local collapse as the numerical solution becomes increasingly unstable and thus difficult to reach. There are several commercially available Finite Element Analysis software's such as CSI-SAP2000 and CSI-PERFORM-3D, MTR/SASSI, Scia Engineer-ECtools, ABAQUS , and Ansys , all of which can be used for

7007-406: The purpose, namely: Viscous Dampers have the benefit of being a supplemental damping system. They have an oval hysteretic loop and the damping is velocity dependent. While some minor maintenance is potentially required, viscous dampers generally do not need to be replaced after an earthquake. While more expensive than other damping technologies they can be used for both seismic and wind loads and are

7098-445: The same period the meeting hall they'd established on the upper floor served as a popular venue for local gatherings, social events, and church services. Framing (construction) Framing , in construction , is the fitting together of pieces to give a structure , particularly a building , support and shape. Framing materials are usually wood , engineered wood , or structural steel . The alternative to framed construction

7189-556: The seismic performance evaluation of buildings. Moreover, there is research-based finite element analysis platforms such as OpenSees , MASTODON, which is based on the MOOSE Framework , RUAUMOKO and the older DRAIN-2D/3D, several of which are now open source. Research for earthquake engineering means both field and analytical investigation or experimentation intended for discovery and scientific explanation of earthquake engineering related facts, revision of conventional concepts in

7280-476: The stones. The stones of the dry-stone walls built by the Incas could move slightly and resettle without the walls collapsing, a passive structural control technique employing both the principle of energy dissipation (coulomb damping) and that of suppressing resonant amplifications. Typically the tuned mass dampers are huge concrete blocks mounted in skyscrapers or other structures and move in opposition to

7371-471: The structural behavior when damage (i.e., non-linearity ) appears. Numerical step-by-step integration proved to be a more effective method of analysis for multi-degree-of-freedom structural systems with significant non-linearity under a transient process of ground motion excitation. Use of the finite element method is one of the most common approaches for analyzing non-linear soil structure interaction computer models. Basically, numerical analysis

7462-406: The structure its vertical support, and the box-shaped floor sections with joists contained within length-long post and lintels (more commonly called headers ), support the weight of whatever is above, including the next wall up and the roof above the top story. The platform also provides lateral support against wind and holds the stick walls true and square. Any lower platform supports the weight of

7553-478: The study of the behavior of structures and geo-structures subject to seismic loading ; it is considered as a subset of structural engineering , geotechnical engineering , mechanical engineering , chemical engineering , applied physics , etc. However, the tremendous costs experienced in recent earthquakes have led to an expansion of its scope to encompass disciplines from the wider field of civil engineering , mechanical engineering , nuclear engineering , and from

7644-464: The supports are more numerous and smaller, such as balloon , platform , light-steel framing and pre-built framing. Light-frame construction using standardized dimensional lumber has become the dominant construction method in North America and Australia due to the economy of the method; use of minimal structural material allows builders to enclose a large area at minimal cost while achieving

7735-432: The use of synchronized real-time data and video; collaborate with colleagues to facilitate the planning, performance, analysis, and publication of research experiments; and conduct computational and hybrid simulations that may combine the results of multiple distributed experiments and link physical experiments with computer simulations to enable the investigation of overall system performance. These resources jointly provide

7826-499: The wall finish used. Where a partition does not contain a swinging door, 1 + 1 ⁄ 2  in ×  3 + 1 ⁄ 2  in (38 mm × 89 mm) studs at 16 in (410 mm) on center are sometimes used with the wide face of the stud parallel to the wall. This is usually done only for partitions enclosing clothes closets or cupboards to save space. Since there is no vertical load to be supported by partitions, single studs may be used at door openings. The top of

7917-410: The wall should be reinforced with a diagonal wood or metal bracing inset into the studs. In jurisdictions subject to strong wind storms (hurricane countries, tornado alleys ) local codes or state law will generally require both the diagonal wind braces and the stiff exterior sheathing regardless of the type and kind of outer weather resistant coverings. A multiple-stud post of at least 3 three studs,

8008-458: The width of the studs and nailed together to form a single unit. Lintels are predominately nailed together without spacers to form a solid beam and allow the remaining cavity to be filled with insulation from the inside. The preferable spacer material is rigid insulation. The depth of a lintel is determined by the width of the opening and vertical loads supported. The complete wall sections are then raised and put in place, temporary braces added and

8099-482: Was also known as "Chicago construction" in the 19th century. Balloon framing uses long continuous framing members ( wall studs ) that run from the sill plate to the top plate, with intermediate floor structures let into and nailed to them. Here the heights of window sills, headers and next floor height would be marked out on the studs with a story pole . Once popular when long lumber was plentiful, balloon framing has been largely replaced by platform framing . It

8190-484: Was superseded by balloon framing beginning in the 1830s. Balloon framing makes use of many lightweight wall members called studs rather than fewer, heavier supports called posts; balloon framing components are nailed together rather than fitted using joinery . The studs in a balloon frame extend two stories from sill to plate. Platform framing superseded balloon framing and is the standard wooden framing method today. The name comes from each floor level being framed as

8281-592: Was traditionally limited to four floors but some jurisdictions have modified their building codes to allow up to six floors with added fire protection. Earthquake engineering Earthquake engineering is an interdisciplinary branch of engineering that designs and analyzes structures , such as buildings and bridges , with earthquakes in mind. Its overall goal is to make such structures more resistant to earthquakes. An earthquake (or seismic) engineer aims to construct structures that will not be damaged in minor shaking and will avoid serious damage or collapse in

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