Severe flooding events in recent years have underlined the importance of accurate hydrological modelling in urban areas. There are many important parameters relating to both the rainfall distribution and properties of the land on which the rain falls that controls the impacts of the rain event. While the importance of input parameters such as initial water content, topography and extent of hardened surfaces is widely known, their impact on hydrological response in urban areas is not thoroughly understood. In 2017, scientists from the Swedish Meteorological and Hydrological Institute, SMHI, presented five empirical hyetographs based on long-term Swedish municipal rain data (Olsson, et al., 2017). The hyetographs vary in location of peak and distribution of intensity. Olsson (2019) evaluated the hydrological response in terms of water depth of the hyetographs in relation to Chicago Design Storm (CDS), a common design storm used in Swedish hydrological modelling, and found that CDS nearly always overestimates the hydrological response in comparison to the empirical hyetographs, meaning historical rainfall intensity distributions, developed by SMHI.  The aim of this thesis is to analyse the robustness of empirical hyetographs by conducting a sensitivity analysis of a generic urban model with a variation of input parameters. A statistical analysis of data on hardened surfaces, topography and initial water content was conducted to find the median, 5th and 95th percentile respectively of the range of values in Swedish conditions. These values were applied to a synthetic urban model and run together with the five empirical hyetographs and CDS in MIKE 21. The results indicate that the empirical hyetographs are not very robust relating to variations in infiltration capacity (initial water content and amount of hardened areas), while they are more robust when varying the topography. The variation of topography also resulted in large variations in water depth, time to peak and extent of flooded area, while variation of initial water content and amount of hardened surfaces had smaller, although still clear, effects. Furthermore, the results show that hyetographs with a late peak are more sensitive to variations in initial water content and hardened surfaces than hyetographs with an early peak. On average, CDS estimates the response in comparison to the empirical hyetographs accurately, with an average overestimation of 0.5%, but does not capture the range and complexity of the empirical hyetographs. Including the frequency of the different hyetographs, CDS gave an overestimation of 5% compared to the empirical hyetographs. The highlight the uncertainty in using CDS as input for urban cloudburst modelling, but limitations in form of catchment properties in a study area and the importance of the input values limits the generability of the study. / De senaste årens allvarliga översvämningshändelser har understrukit vikten av noggrann hydrologisk modellering i stadsområden. Även om betydelsen av parametrar som initial vattenmättnad, topografi och andelen hårdgjorda ytor är allmänt känd, är deras inverkan på urban hydrodynamisk modellering inte helt klarlagd. Under 2017 presenterade forskare från Sveriges Meteorologiska och Hydrologiska Institut, SMHI, fem empiriska hyetografer baserade på långvariga kommunala regndata (Olsson et al., 2017). Hyetograferna varierar i fördelning av intensitet och tidsmässig placering av maxintensitet. Olsson (2019) utvärderade hyetografernas hydrologiska respons i relation till Chicago Design Storm (CDS), en vanlig designstorm som används i svensk hydrologisk modellering, och fann att CDS nästan alltid överskattar responsen i jämförelse med de empiriska hyetograferna.  Syftet med detta examensarbete är att analysera robustheten hos de empiriska hyetograferna genom att utföra en känslighetsanalys av en generisk stadsmodell med en variation av ingångsparametrar. En statistisk analys av data om hårdgjorda ytor, topografi och initial vattenmättnad genomfördes för att hitta median, 5:e respektive 95:e percentilen av värdena i svenska förhållanden. Dessa värden applicerades på en generisk stadsmodell och kördes tillsammans med de fem empiriska hyetograferna och CDS i MIKE 21. Resultaten indikerar att de empiriska hyetograferna inte är helt robusta vad gäller variationer i infiltrationskapacitet (initial vattenmättnad och andel hårdgjorda ytor), medan de är mer robusta vid variation av topografin. Variationen av topografi resulterade också i stora variationer i vattendjup, tid till maxflöde och utbredning av översvämmat område, medan variation av initial vattenmättnad och mängden hårdgjorda ytor hade mindre, men fortfarande tydliga, effekter. Vidare visar resultaten att hyetografer med sen topp är känsligare för variationer i initial vattenhalt och hårdgjorda ytor än hyetografer med tidig topp. I genomsnitt uppskattar CDS responsen från de empiriska hyetograferna korrekt, med en genomsnittlig överskattning på 0.5%, men fångar inte omfånget och komplexiteten hos de empiriska hyetograferna. Inräknat frekvensen av de olika hyetograferna gav CDS en överskattning på 5 % jämfört med de empiriska hyetograferna. Resultaten belyser osäkerheterna i att använda CDS regn som drivdata i skyfallsmodelleringar för stadsplanering, men begränsningar i form av markegenskaper i ett enskilt studieområde och vikten av modellens initialvärden begränsar dock generaliteten för studien.

Expansive or swelling soils, exist in many part of the world, show excessive volume changes with increasing water content. As a result of this volume increase, expansive soils apply vertical and lateral pressures to the structures located or buried in these regions. Many researchs have been carried out on vertical swelling pressures helping to the engineers to design structures withstanding on these stresses. However, lateral swell behaviour of swelling soils have not been fully understood yet. Structures such as / basement walls, water tanks, canals, tunnels, underground conduits and swimming pools which will be built in expansive soils have to be designed to overcome the lateral swelling pressures as well as the other lateral pressures exerted by the soil. For this aim accurate and reliable methods are needed to predict the magnitude of lateral swelling pressures of expansive soils and to understand the lateral swelling behaviour of expansive soils. In this experimental study, the lateral swelling behaviour of an highly expansive clay is investigated using a modified thin wall oedometer which was developed in the METU Civil Engineering Department Soil Mechanics Laboratory earlier. Statically compacted samples were used in constant volume swell (CVS) tests to measure the magnitude of the lateral and vertical swelling pressures. To study the relationship between the lateral and vertical sweeling pressures, they were measured simultaneously. The samples having different initial water contents and different initial dry densities were used to study the effects of these variables on the vertical and the lateral swelling pressures. It is observed that both lateral and vertical pressures increases with increasing initial dry density and they decrease with increasing initial water content. Swell pressure ratio, the ratio of lateral swelling pressure to the vertical one, is increasing with increasing initial water content. Time needed to obtain the magnitude of maximum lateral and vertical pressures decreases with increasing initial water content and increases with increasing initial dry density.