The 2010-2011 Canterbury, New Zealand, Earthquake Sequence (CES) resulted in 185 fatalities and approximately $NZ40 billion in damage, much of which was due to liquefaction and related phenomena. As a result, an extensive soil improvement field testing program was initiated and Rammed Aggregate Piers� (RAP) were shown to be a feasible method to mitigate the risk from liquefaction during future events. To better design and more fully assess the efficacy of reinforcement techniques against liquefaction, pre- and post-treatment in-situ test data are compiled, to include results from cone penetration tests (CPT), direct-push crosshole tests, and vibroseis (T-Rex) shaking tests. The data are used to evaluate the capabilities of numerical tools to predict the liquefaction response of unimproved and improved sites. A finite difference (FD) numerical model is developed in a FLAC platform and a coupled analysis using the Finn model with Byrne (1991) formulation is conducted. The FD model calibrated for top-down shakings similar to the vibroseis tests succeeded in qualitatively reproducing the general observed behavior without quantitatively matching the in-situ values for shear strains and excess pore pressure ratios. The introduction of the RAP elements to the FD model reduced the shear strain, but slightly overestimated that reduction. Considering more advanced constitutive models that better simulate the complexity of the soil behavior under dynamic loading would likely increase the accuracy of the predicted response. / MS / During earthquakes, a significant loss of strength in soil can occur. This phenomenon, known as liquefaction, can have a devastating impact on the area affected. The 2010-2011 Canterbury, New Zealand, Earthquake Sequence (CES) resulted in 185 fatalities and approximately $NZ40 billion in damage, much of which was due to liquefaction and related phenomena. Consequently, the New Zealand Earthquake Commission implemented a field testing program in order to investigate the efficiency of ground improvement techniques in reducing soil liquefaction potential. One of the tested techniques was Rammed Aggregate Piers™ (RAP) and was shown to be a feasible method in mitigating the risk from liquefaction during future events. The focus of this study is to develop a numerical model capable of predicting the liquefaction response of unimproved and RAP-improved sites. Pre- and post-treatment test data are therefore compiled and used to calibrate the model. The numerical model calibrated for shakings similar to the on-site tests succeeded in qualitatively, but not quantitatively, reproducing the behavior observed in the field. The introduction of the RAP elements to the model revealed an improvement against liquefaction hazard; however, the improvement was overestimated compared to the field results. Considering more advanced numerical features that better simulate the complexity of the soil behavior under dynamic loading would likely increase the accuracy of the predicted response.

Rammed earth is one of the earliest building materials used for structural walls. Stabilised rammed earth is a variant of traditional or pure rammed earth that involves addition of a small amount of cement to improve strength and durability. Rammed earth buildings experience in-plane shear forces as well as flexural stresses due to out-of-plane bending especially during earthquakes. The thesis attempts to examine the behaviour of cement stabilised rammed earth wall elements and building models subjected to lateral loads. A brief introduction to rammed earth construction followed by a review of literature on rammed earth and details of the existing codes of practice on rammed earth is provided in Chapter 1. Chapter 2 deals with the flexural strength, modulus of rupture, stress-strain relationships and free vibration characteristics of cement stabilised rammed earth (CSRE) in greater detail. Properties of raw materials used in the experimental investigations followed by a detailed description of the experimental programme, method of preparation of various types of specimens and their testing procedures are provided. Flexure strength and modulus of rupture were determined in both the orthogonal directions. Influence of (a) thickness of the specimen, (b) direction of compacted layers with respect to the flexural tension developed and (c) effect of cement slurry coating between the compacted layers on the flexural strength of CSRE were examined. The investigations show that flexure strength increases with the increase in the specimen thickness and a coat cement slurry on the compacted layers leads to improvement in flexure strength. The flexural strength parallel to compacted layers is higher when compared to flexure strength perpendicular to compacted layers. Stress-strain relationships show that the initial tangent modulus of CSRE in saturated condition is about 60% of that in dry condition. Damping ratio as obtained from the free vibration studies is found to be 0.022 in the two orthogonal directions. Dynamic characteristics of CSRE building models are presented in Chapter 3. A simple alternative to shake table called as “Shock Table” was used in the present investigation for providing base motion to the building model. A half-scale CSRE building model with R.C lintels only above door and window openings (with no earthquake resistant features) was constructed on the Shock Table. The wall thickness of the building model was 100 mm. Procedure for construction, instrumentation and testing of the CSRE building model is presented. Responses measured and damages observed are discussed in detail. Finite element (FE) analyses were performed on six different building models with different earthquake resistant features using commercially available FE software (NISA V17). Both free vibration and forced vibration analyses were performed. Natural frequencies and forced vibration responses (acceleration) of building model (BM1) obtained from experiment and FE analysis were compared. Responses (free vibration and forced vibration) of other five building models were predicted using FE analysis. Crack patterns of the building models with roof and without roof are compared. The thesis ends with a summary of the results and concluding remarks in Chapter 4.

Pisé de terre or rammed earth is a building technique that has existed for over ten thousand years. Although this technique was first documented for Western Civilization by the Roman Pliny the Elder circa 79 AD, evidence of its use prior to his time is found in China, Europe, and elsewhere. Rammed earth achieved notoriety in the United States during three distinct periods in its history: the Jeffersonian era, the Great Depression, and the Back-to-Nature Movement of the 1970s. In the United States earth buildings are uncommon and usually deemed marginal or fringe. This is true even though at times the U.S. government has been a proponent of alternative building techniques, especially rammed earth. Intended for those interested in material culture, this thesis provides a brief history of rammed earth, articulates its importance to the building record of the United States, and describes methods for its preservation, repair, and maintenance.

Lágin (pron. laoyin)  is an old Icelandic word I came across in my great grandfather’s writings. Lágin translates to a dip in the landscape but in regards to my project, Lágin is the name of a writers retreat I've designed by the farmstead Hali in Suðursveit, Iceland. The retreat partly builds on the legacy and philosophy of my great grandfather, Þórbergur Þórðarson. Born in 1888 and died in 1974, he is one of Iceland’s most beloved authors and poets. In addition to that source material, I reference the unique architectural heritage of Iceland for much of the project’s atmosphere, material pallette and architectural logic. Lágin allows for 10 guests while housing a staff of two. One staff member to organize the operation and lead the guests in their yoga, meditation and exercise rituals. The other staff member tends to the retreats’ vegetable garden, cooks meals and handles general daily functions. An established resident writer will periodically stay at Sléttaleiti, a nearby house owned by the Writers’ Union of Iceland. That writer will come by Lágin for organized meet ups with the guests to guide and progress on their work through private conversation.

This thesis aims to establish a context of the relationship between internal and external elements of a villa in Shaqra, Saudi Arabia. The study tends to represent the surrounding environment through the use of local and readily available building materials, rammed earth, in constructing the structural building walls. The walls of the villa designed to be built with the rammed earth, as they seem they grow out of the ground and belong to the ground, in which it has the same soul and character of the surrounding area. / Master of Architecture

To investigate the liquefaction mitigation capability of Rammed Aggregate Piers® (RAP) in silty sand, blast liquefaction testing was performed at a soil profile treated with a full-scale RAP group relative to an untreated soil profile. The RAP group consisted of 16 piers in a 4x4 arrangement at 2 m center-to-center spacing extending to a depth of 9.5 m. Blasting around the untreated area induced liquefaction (ru ≈1.0) from 3 m to 11 m depth, producing several large sand boils, and causing settlement of 10 cm. In contrast, installation of the RAP group reduced excess pore water pressure (ru ≈0.75), eliminated sand ejecta, and reduced average settlement to between 2 to 5 cm when subjected to the same blast charges. Although the liquefaction-induced settlement in the untreated area could be accurately estimated using the CPT-based settlement approach proposed by Zhang et al. (2002), settlement in the RAP treated area was significantly overestimated with the same approach even after considering RAP treatment-induced densification. Analyses indicate that settlement after RAP treatment could be successfully estimated from elastic compression of the sand and RAP acting as a composite material. The composite reinforced soil mass, surrounded by liquefied soil, transferred load to the base of the RAP group inducing settlement in the non-liquefied sand below the group. This test program identifies a mechanism that explains how settlement was reduced for the RAP group despite the elevated ru values in the silty sands that are often difficult to improve with vibratory methods.

Examensarbetet Jordhuset består av två delar där den första delen handlar om jordarkitektur och mina jordexperiment. Den andra delen är ett resultat av mina undersökningar och mitt gestaltande förslag till ett jordhus i det svenska klimatet. Jag vill introducera ett miljövänligt och hållbart alternativ till de konventionella byggmaterialen betong, trä och stål samt erbjuda en ny form av arkitektonisk estetik som jordhus möjliggör.  Jord är vårt mest miljövänliga byggnadsmaterial och står för 0 % av världens koldioxidutsläpp – jämfört med t ex framställningen av betong och cement som står för 7 % av koldioxidutsläppen varje år. Genom att undersöka och experimentera med materialet så skapar jag mig en egen uppfattning om dess kvaliteter och utmaningar. / The thesis project Jordhuset consists of two parts where the first part is about earth architecture and my earth experiments. The second part is a result of my research and my design proposal for an earth house in the Swedish climate. I want to introduce an environmentally friendly and sustainable alternative to the conventional building materials concrete, wood and steel and offer a new form of architectural aesthetics that earthen houses make possible. Soil is our most environmentally friendly building material and accounts for 0 % of the world’s carbon dioxide emissions - in comparison with the production of concrete and cement, which accounts for 7 % of carbon dioxide emissions each year. By researching and experimenting with the material, I create my own perception of its qualities and challenges.

Stampad lerjord är ett byggmaterial som använts under människans historia där vissa konstruktioner står än idag. Tekniken bakom materialet är simpelt, men saknar till viss del modern forskning för att det ska kunna integreras till en standard som till viss del kan ersätta betong. I rapporten samlas empiriskt data som kan öppna nya idéer samt leda till framtida möjligheter för forskning när det kommer till att integrera stampad lerjord som en standard för att designa framtida konstruktioner för ett mer hållbart byggande. Metodiken går ut på att genom praktiska experiment, tillverka samt utföra tester på jord samt tryckhållfasthet hos flertal kuber tillverkade i stampad lerjord. Alla tester och provkroppar utförs i ett betonglabb på Högskolan i Halmstad, sedan analyseras och diskuteras den data som givits. Resultatet jämförs därefter med styrkan hos betongklassen C16/20 som motsvara en tryckhållfasthet på 20 MPa för kuber. De 18 kuber som tillverkats innehåller blandningar med jord, vatten och cement. Provkropp nummer 2 adderas med halm. Härdningsprocessen uppgår till 7, 14 och 28 dagar för de två olika blandningar som analyseras. Totalt tillverkas det tre exemplar för respektive härdningsdag samt de två olika blandningar. Det maximala medelvärdet för tryckhållfastheten ges efter 28 dagar. Det existerar tillräckligt mycket allmän information om hur tillverkningen utförs, men saknar till viss del data som beskriver hur olika faktorer påverkar det slutgiltiga resultatet. Därav är frågeställningen anpassad för att på ett experimentellt vis kunna analysera de påverkade faktorerna. Koldioxidutsläpp vid produceringen av cementen som används vid tillverkning av betongklass C16/20 är baserat på produktblad för bascement från Cementa (2020) för att beräkna den mängd cement som krävs för nå upp till den önskade tryckhållfastheten. Beräkningen för utsläppen är en approximation då fler faktorer bör räknas in vid det totala utsläppet med hänsyn till transport och bränslen. Resultatet visar att kuberna varierar mellan de olika blandningar som framställts, där blandningen utan halm presterar 142% mer med hänsyn till tryckhållfasthet. Denna kub representerar i sin tur 51,7% av tryckhållfastheten hos betongklass C16/20 men minskar samtidigt den brukade cementmängden med 26%. Rapporten visar att materialet fungerar för konstruktioner där låg styrka kan anpassas.

This paper discusses earth as a building material and the extent to which earth building technology has evolved over the years. In particular it addresses the adobe, compressed and rammed earth techniques of earth building as suitable techniques for Liberia consumption. In addition, the paper investigates the suitability of the Latosols soils of Liberia for earth building construction purposes using standardized earth building principles and requirements. A local Johnson City, Tennessee, earth sample found to have the same physical characteristics of the Latosols of Liberia was used to simulate Liberia soils to produce specimen blocks at different configurations of moisture content and stabilizers (Bentonite and cement). Following 14 days of cure, the blocks were tested for compressive strength. It was found that blocks produced from the natural soil with no stabilizer added were structurally adequate for building construction purposes. A cost-benefit analysis involving blocks with and without stabilizer (cement) added was also performed.

The plot is situated south of the small village Alberga in the south west of the municipality of Eskilstuna. The project is an example of how a landscape can be made accessible for people and through emotional conection be considered worth protecting, and at the same time offer a house for community. This is done with a House for the People - Folkets hus - together with a small spa inspired public bath with a fireplace in is center, and a research facility for conducting limnological and ecological research in the close marshy area and the lake Hjälmaren. The building is situated on top of three man made ponds, one new for the project, held upp by low pillars giving the house a floating impression. The architecture consists of a timber structure suported by rammed earth walls, the earth taken from the site when constructiong af a new pond. The three different usages of the program is separated into its own body and connecting them is a series of walkways, in some places suspended from the timber rafters. The project should... - Bring the community together in a flexible meeting place for many different activities- Preserv and strengthen a landscape´s ecology - Put a small village on the map and build a larger net of interconnectedness / Tomten ligger söder om den lilla byn Alberga i sydvästra Eskilstuna kommun. Projektet är ett exempel på hur ett landskap kan göras tillgängligt för människor och genom känslomässig koppling anses värt att skydda, och samtidigt erbjuda ett hus för gemenskap. Detta görs med en hybridbyggnad av ett Folkets hus tillsammans med ett litet spa-inspirerat bad med öppen spis i centrum samt en forskningsanläggning för att bedriva limnologisk och ekologisk forskning i det närliggande våtmarksmrådet och sjön Hjälmaren. Byggnaden ligger ovanpå tre konstgjorda dammar, en ny för projektet, hållna uppe av låga pelare som ger huset ett flytande uttryck. Arkitekturen består av en limträkonstruktion som bärs upp av stampade jordväggar, jorden hämtad från platsen vid anläggandet av en ny damm. De tre olika användningsområdena för programmet är uppdelade i varsin kropp och är sammankopplande med bryggor.Projektet ska... – Föra samman boende i takten genom samlingslokaler för flera olika aktiviteter - Ta till vara på ett unikt landskap samt att stärka dess ställning och ekologi – Gynna bygdens tillväxt med besöksnäring genom attraktivt besöksmål