The weakest points in concrete pavement systems are the concrete joints. They are man-made cracks that allow for temperature-related expansion and contraction of concrete slabs. Sealants are commonly used in pavement joints to keep debris, deicing chemicals, and moisture out of the joint. When a joint sealant fails, the pavement can quickly deteriorate; however, when a joint sealant functions well, the pavement maintains its intended performance. Joint sealants are subjected to two forms of mechanical loads in the field: 1) as slabs contract or expand, the sealant is subjected to tension or compression, respectively; and 2) heavy vehicles travel over the joint and deflect the ends of the pavement slabs, causing sealants to shear. Sealants may also be exposed to a range of environmental factors, such as moisture and ultraviolet radiation. In this research project, to simulate the joint sealant performance, samples were made by buttering the three different silicone sealants, namely Sealant 1, Sealant 2, and Sealant 3, between 1" x 1" x 3" Portland Cement Concrete dogbone-shape samples and 0.2" x 1" x 3" glass substrate samples were prepared according to VTM 90 and ASTM C1135, respectively. The tests were carried out employing an Instron Tensile Testing Machine and unique fixtures designed at Virginia Tech to impart mechanical loading. In comparison to Sealant 2, the results demonstrated that Sealant 1 can withstand larger stresses. All the concrete samples failed due to adhesive failure, whereas some of the Sealant 1 glass samples failed due to adhesive failure at low peak loads and others failed due to a combination of adhesive and cohesive failure. Glass samples of Sealant 2 on the other hand showed just cohesive failure. In case of Sealant 3, samples of both ASTM C1135 and VTM #90 showed adhesive failure and failed by showing reasonable strength. / Master of Science / Concrete pavements have a number of man-made joints that separate adjacent slabs. The purpose of these joints is to allow relatively free concrete expansion and contraction owing to changes in temperature and moisture. To ensure longevity of concrete, these joints must be sealed with a long-lasting material that can protect the joints from moisture, dust, and de-icing salts. The focus of this study is on silicone sealants, which have used for years as a joint sealant material. Three different silicone-based sealants were used. And two test methods, VTM-90, and ASTM C1135, were used to conduct the tensile testing. VTM-90 provides the test method to determine bond of silicone sealant to concrete mortar while ASTM C1135 gives the procedure for quantitative measure of tensile adhesion properties of structural sealants. ASTM C1135 In comparison to Sealant 2, the test results showed that Sealant 1 can withstand high loads. All the VTM-90 samples of Sealant 1, 2 and 3, failed because of adhesive failure, whereas some of the Sealant 1 ASTM C1135 samples failed because of adhesive failure at low peak loads and others because of a combination of adhesive and cohesive failure. On the other hand, ASTM C1135 samples of Sealant 2 showed only cohesive failures while Sealant 3 samples showed adhesive failure.

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Investigation of more than seventy highway bridges revealed that multisimple-span skew bridges with expansion joints were very common in Turkish practice. The expansion joints, used to provide deck expansion against shrinkage, creep and thermal effects, create costly maintenance problems due to leaked water, impact loads and accumulated debris in the joints. Therefore, elimination of expansion joints decreases the maintenance cost for the bridges. Reinforced concrete link slabs provide continuity at the deck level with the elimination of expansion joints. This thesis focuses on evaluating the seismic behavior of the skew multisimple-span bridges in Turkey and also discusses the use of reinforced concrete link slabs as a seismic retrofit option. The effects of addition of link slab and varying skew angle on the performance of the bridges were investigated. The use of link slabs can provide a better seismic displacement control, can decrease the member forces and can prevent or reduce deterioration of the top of the piers and ends of the girders from the water and chemical leakage by abandoning or minimizing number of expansion joints.

Following development of rectangular prestressed, precast concrete panels (PCP) that could be used as stay-in-place formwork adjacent to expansion joints in bridge decks, the Texas Department of Transportation (TxDOT) initiated a research effort to investigate the use of PCP units at skewed expansion joints. The fabrication of trapezoidal PCP units was studied and the response of skewed panels with 45° and 30° skew angles was obtained. The panels were topped with a 4 in. thick cast-in-place (CIP) slab to complete the bridge deck. Specimens with 45° skew performed well under service and overload levels. The deck failed in diagonal shear at loads well over the design level loads. However, two 30° specimens failed prematurely by delamination between the topping slab and the PCP. The cause of the delamination was insufficient shear transfer capacity between the PCP and CIP topping slab. For the specimens tested at a square end, the failure mode was punching shear at high loads for all specimens. The surface condition of the PCP was specified to have a “broom finish” and the panel was to have a saturated surface dry (SSD) condition so that PCP units would not leach moisture from the CIP topping slab. Neither of these conditions was satisfied in the two panels that failed prematurely. Although the panels were specified to have a broom finish, the panel surface had regions that were quite smooth. The objective of this research project was to reinvestigate the response of 30° PCP at an expansion joint following specified procedures for finish and moisture conditions. One specimen was constructed with a rectangular panel placed between two 30° skewed panels. These panels had a much rougher surface texture than the previously tested panels that failed in delamination. The skewed ends of the specimen were subjected to monotonically increasing static loads at midspan of the panel ends. The panels failed in diagonal shear and the response of the tested specimen confirmed that the panel surface roughness, and not the skew angle, caused delamination with the previously tested specimens. While TxDOT does not currently specify a minimum panel surface roughness, a surface roughness of approximately 1/4 in. is required in some codes for developing composite action. In addition, wetting the panels to a SSD condition prior to placement of the topping slab further enhances shear transfer between the topping slab and the PCP. / text

Bridge expansion joints are directly subjected to traffic load, and thus prone to premature fatigue failure. Replacement of components such as modular bridge expansion joints is typically done in a staggered schedule to minimize traffic blockage. Field splices are used to connect the successively installed segments. These splices typically include a combination of field welding or bolting, and experience has shown that they often fail due to fatigue cracking. This thesis reports the investigation of hybrid FRP/steel splice details that avoid the use of field welding. Two configurations have been examined: A GFRP pultruded square tube section, adhesively bonded to the soffit of the spliced beam, consists the moment resisting component in one configuration, whereas the other takes advantage of two series of FRP plates for this purpose. Bolted steel plates splice the beam through web in both cases. The behaviour of these details has been studied extensively under vertical static loads. The effect of several parameters including bond length, FRP end shape, bond surface treatment, adhesive, etc. for each detail has been investigated. A three-dimensional, non-linear finite element model has been developed for each detail and validated using the experimental results. The bond strength of two adhesives was investigated experimentally using double shear lap splice tests. A new method is proposed to analyze the strength of the splice details. This method is based on the results obtained from shear lap splice tests and the verified finite element model developed for the splice detail. The finite element model could thus be used for further parametric studies. More experiments, however, are statistically required before using this model with confidence. The fatigue behaviour of one of the promising splice details has been investigated both experimentally and numerically. A special fatigue test set-up has been designed and used successfully for this purpose. Two fatigue tests to 1,000,000 cycles were run. One failed at 719, 347 cycles and the other survived 1,000,000 cycles. The predicted fatigue life as per the developed model was 871,840 cycles. More experiments are required to understand the fatigue behaviour of the splice detail under various stress ranges. / Thesis (Ph.D, Civil Engineering) -- Queen's University, 2011-11-30 16:53:07.385

Rehabilitation and maintenance of the aging transportation infrastructure are of major concern in the Province of Ontario. A large portion of this work is related to the durability of highway bridges around the province. One of the weakest points in a bridge structure from a durability aspect is the expansion joints that can allow harmful elements, such as road salts and contaminants to leak down from the road surface and attack the supporting structure of the bridge. Although expansion joints can be eliminated in the design of a new bridge, such as in an integral abutment bridge, this requires major changes to the supports and structure of the bridge, making it impractical for retrofitting existing bridges. One effective alternative is the replacement of a traditional expansion joint with a link slab. A link slab is a concrete slab used in place of an expansion joint to make the bridge deck continuous while keeping the supporting girders simply supported [1]. Link slabs must be able to resist large force effects both in bending and direct tension while minimizing cracking [2], one solution is to use the high tensile and flexural strength properties of an ultra-high performance fibre-reinforced concrete (UHPFRC) [3]. The UHPFRC mixtures are often proprietary and expensive. The purpose of this research was to evaluate the potential of using common fibre types with standard concrete ingredients in a fibre-reinforced concrete (FRC) as an alternative to UHPFRC in a link slab. Using a selection of macro fibres commonly used in slab on grade applications for crack control, an optimized FRC mixture was developed following the principals established by Rossi and Harrouche [4]. This mixture was then used with a variety of fibre types to evaluate the structural and durability properties of the FRC. Testing was conducted for fresh mixture properties, compressive, tensile and flexural strength as well as freezing and thawing resistance, linear shrinkage, environmental and salt exposure along with other durability tests. Results showed that the concrete mixture used for an FRC link slab should consist of; an equal ratio of fine and coarse aggregate by weight and a higher than normal percentage of cement paste, for optimal workability and a dosage of 1.5% by volume of macro steel fibres. Hooked-end steel fibres resulted in the best performance increase to the FRC of the six fibre types tested. Results also showed that reinforcing cage for an FRC link slab should be designed to ensure that fibres can evenly reach all areas of the link slab form to give homogeneous fibre distribution. Although the FRCs created did not perform to the high level of a UHPFRC, these results show a consistent and effective FRC can be created, for use in a link slab with common fibres and standard concrete materials to provide a less expensive and more widely available FRC link slab than UHPFRC.

To design a bridge, different typologies of construction materials can be used. All materials have in common that deformations occur due to different events, such as externalloading, temperature- and moisture variations. To allow these kinds of deformations,Expansion Joints (EJs) are used in the structure. In timber bridges, these joints haveturned out to be a complex construction detail, due to problems related to their strengthand moisture capacity. The purpose of this thesis is to overview design codes and tostudy the mechanical behavior of Nosing EJs in a roadway timber bridge under externalloading. The aim is to identify critical actions and provide an alternative design of thestudied EJ. The aim is also to create a Finite Element (FE) model of the EJs and carryout calculations according to the design codes. To achieve this, literature studies, designcalculations and FE-simulations were performed. It turned out that there were lack ofearlier studies within this field. Therefore, studies which treats EJs in bridges with othermaterial than timber were considered. The results from the simulations indicated thatthe steel components in EJs are the most exposed parts in the detail. It also turned outthat an eventual failure can transferred away from the screws to the parts consideredmore favorable in the EJ.

This thesis discusses the types of bridge expansion joints certified for use in the Czech Republic and their disorders. The first part was a theoretical evaluation of expansion joint failures. The second part focused on clarifying the failure of anchor bolts at the cantilever expansion joint. On the basis of determining the cause was then designed a method for determining the durability of expansion joints. Prognosis life cycles corresponds records according to administrator- repair works.

Informationen gällande dilatationsfogar är i dagsläget otydlig ochkonstruktörer ifrågasätter användandet av dem. Avsaknaden aven tydlig standard medför att användandet blir inkonsekvent.Behovet av att standardisera eller utförligt beskriva de viktigafaktorerna som spelar in är efterfrågat. Den främstaproblematiken ligger i avståndet mellan dilatationsfogar och när,eller om de är nödvändiga.Detta examensarbete har utförts i samarbete med avdelningenProperty & Buildings på WSP Uppsala i syfte om att spridakunskap om användandet av dilatationsfog inom konstruktion.Målet med arbetet är att effektivisera byggbranschensanvändande av dilatationsfogar. Studien framför ett antal nugällande rekommendationer från olika källor i litteraturstudiensamt tre intervjuer med erfarna konstruktörer. Denna informationsammanställs sedan i resultatet och slutsatsen, där en egen teoriframförts i förhoppning om att klargöra otydligheter inom ämnetsamt inspirera till vidare studier.Studien visar att sprickbildning är den främsta anledningen tillbehovet av en dilatationsfog och att många olika faktorer påverkaruppkomsten av sprickor. De faktorer som påverkar mest ärbyggnadens underlag och geometrin på betongkonstruktionen dådessa kan leda till rörelser i betongen och tvång. Utöver dessatekniska faktorer inverkar projektets ekonomi på användandet avdilatationsfogen. Detta leder till att varje enskilt fall börundersökas för att använda fogen effektivt, men studien visar påatt ett avstånd på 30 meter kan anses säkert. / Today's information regarding expansion joints is lacking and construction engineersare questioning the use of them. The absence of a distinct standard results ininconsistent usage.A standardization or a thorough description of the important factors taking place in thesubject is requested. The main issue regards the distance between expansion joints andwhen or if they are necessary.The purpose of this study is to spread knowledge regarding the use of expansion jointswithin construction and the work has been done in cooperation with the Property &Buildings department at WSP Uppsala. The end goal is to increase efficiency of the usageof expansion joints within construction. This study features several presentrecommendations from different written sources as well as three interviews withknowledgeable construction engineers. The information gathered is concluded andpresented in the results and conclusion parts of the report. To clarify the ambiguitiesregarding the subject and to inspire further research a theory has been presented aswell.The study shows that cracking is the main reason for usage of expansion joints and theorigin of cracks depends on many different elements. Mainly it is the buildingsgroundwork and the geometry of the different concrete construction units that lead tovarious movement and constrain damage. Alongside these elements the project's budgetdirectly affects usage of expansion joints. These factors all indicate that every uniquecase should be studied to assess the necessity and effective usage of expansion joints,however the study has shown that 30 meters between joints can be considered safe.

The diploma thesis deals with the project of the horse-riding grounds situated near the town of Žďár nad Sázavou. The complex of buildings consists of two riding halls, a groundskeeper’s flat, stables with a zone for riders and outside stable-boxes for horses. The buildings are laid out in a way to create a closed farmyard. There is a built-in unit located in the larger hall together with accommodation and restaurant with a great view to the riding hall. The horse-riding grounds are used for equitation In the first place. The two outside sandy riding arenas and the two indoor halls give an ideal opportunity for regular horse training as well as riders training. The halls would be also useful for holding the riding works all year round. It is possible to stable 19 horses in the indoor stable and 8 more in the outside stable-boxes in the farmyard. This diploma thesis deals with the project of horse-riding hall with a built-in unit, it also deals with a project for the groundskeeper’s flat and outside stable-boxes for horses. In the framework of the diploma thesis two specialties were elaborated – the project for heating in the built-in unit and the groundskeeper’s flat as well as the project for roofing the riding hall with the glue laminated timber girder. There are seminar paper and architectonic sketches included in the diploma thesis.